WebSVN – Kolibri OS – Diff – /drivers/video/drm/drm_dp_mst_topology.c


/*
 * Copyright © 2014 Red Hat
 *
 * Permission to use, copy, modify, distribute, and sell this software and its
 * documentation for any purpose is hereby granted without fee, provided that
 * the above copyright notice appear in all copies and that both that copyright
 * notice and this permission notice appear in supporting documentation, and
 * that the name of the copyright holders not be used in advertising or
 * publicity pertaining to distribution of the software without specific,
 * written prior permission.  The copyright holders make no representations
 * about the suitability of this software for any purpose.  It is provided "as
 * is" without express or implied warranty.
 *
 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
 * OF THIS SOFTWARE.
 */
 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
 
#include 
 
u64 get_jiffies_64(void)
{
    return jiffies;
}
/**
 * DOC: dp mst helper
 *
 * These functions contain parts of the DisplayPort 1.2a MultiStream Transport
 * protocol. The helpers contain a topology manager and bandwidth manager.
 * The helpers encapsulate the sending and received of sideband msgs.
 */
static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr,
				  char *buf);
static int test_calc_pbn_mode(void);
 
static void drm_dp_put_port(struct drm_dp_mst_port *port);
 
static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr,
				     int id,
				     struct drm_dp_payload *payload);
 
static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr,
				  struct drm_dp_mst_port *port,
				  int offset, int size, u8 *bytes);
 
static void drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
				     struct drm_dp_mst_branch *mstb);
static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr,
					   struct drm_dp_mst_branch *mstb,
					   struct drm_dp_mst_port *port);
static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr,
				 u8 *guid);
 
static int drm_dp_mst_register_i2c_bus(struct drm_dp_aux *aux);
static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_aux *aux);
static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr);
/* sideband msg handling */
static u8 drm_dp_msg_header_crc4(const uint8_t *data, size_t num_nibbles)
{
	u8 bitmask = 0x80;
	u8 bitshift = 7;
	u8 array_index = 0;
	int number_of_bits = num_nibbles * 4;
	u8 remainder = 0;
 
	while (number_of_bits != 0) {
		number_of_bits--;
		remainder <<= 1;
		remainder |= (data[array_index] & bitmask) >> bitshift;
		bitmask >>= 1;
		bitshift--;
		if (bitmask == 0) {
			bitmask = 0x80;
			bitshift = 7;
			array_index++;
		}
		if ((remainder & 0x10) == 0x10)
			remainder ^= 0x13;
	}
 
	number_of_bits = 4;
	while (number_of_bits != 0) {
		number_of_bits--;
		remainder <<= 1;
		if ((remainder & 0x10) != 0)
			remainder ^= 0x13;
	}
 
	return remainder;
}
 
static u8 drm_dp_msg_data_crc4(const uint8_t *data, u8 number_of_bytes)
{
	u8 bitmask = 0x80;
	u8 bitshift = 7;
	u8 array_index = 0;
	int number_of_bits = number_of_bytes * 8;
	u16 remainder = 0;
 
	while (number_of_bits != 0) {
		number_of_bits--;
		remainder <<= 1;
		remainder |= (data[array_index] & bitmask) >> bitshift;
		bitmask >>= 1;
		bitshift--;
		if (bitmask == 0) {
			bitmask = 0x80;
			bitshift = 7;
			array_index++;
		}
		if ((remainder & 0x100) == 0x100)
			remainder ^= 0xd5;
	}
 
	number_of_bits = 8;
	while (number_of_bits != 0) {
		number_of_bits--;
		remainder <<= 1;
		if ((remainder & 0x100) != 0)
			remainder ^= 0xd5;
	}
 
	return remainder & 0xff;
}
static inline u8 drm_dp_calc_sb_hdr_size(struct drm_dp_sideband_msg_hdr *hdr)
{
	u8 size = 3;
	size += (hdr->lct / 2);
	return size;
}
 
static void drm_dp_encode_sideband_msg_hdr(struct drm_dp_sideband_msg_hdr *hdr,
					   u8 *buf, int *len)
{
	int idx = 0;
	int i;
	u8 crc4;
	buf[idx++] = ((hdr->lct & 0xf) << 4) | (hdr->lcr & 0xf);
	for (i = 0; i < (hdr->lct / 2); i++)
		buf[idx++] = hdr->rad[i];
	buf[idx++] = (hdr->broadcast << 7) | (hdr->path_msg << 6) |
		(hdr->msg_len & 0x3f);
	buf[idx++] = (hdr->somt << 7) | (hdr->eomt << 6) | (hdr->seqno << 4);
 
	crc4 = drm_dp_msg_header_crc4(buf, (idx * 2) - 1);
	buf[idx - 1] |= (crc4 & 0xf);
 
	*len = idx;
}
 
static bool drm_dp_decode_sideband_msg_hdr(struct drm_dp_sideband_msg_hdr *hdr,
					   u8 *buf, int buflen, u8 *hdrlen)
{
	u8 crc4;
	u8 len;
	int i;
	u8 idx;
	if (buf[0] == 0)
		return false;
	len = 3;
	len += ((buf[0] & 0xf0) >> 4) / 2;
	if (len > buflen)
		return false;
	crc4 = drm_dp_msg_header_crc4(buf, (len * 2) - 1);
 
	if ((crc4 & 0xf) != (buf[len - 1] & 0xf)) {
		DRM_DEBUG_KMS("crc4 mismatch 0x%x 0x%x\n", crc4, buf[len - 1]);
		return false;
	}
 
	hdr->lct = (buf[0] & 0xf0) >> 4;
	hdr->lcr = (buf[0] & 0xf);
	idx = 1;
	for (i = 0; i < (hdr->lct / 2); i++)
		hdr->rad[i] = buf[idx++];
	hdr->broadcast = (buf[idx] >> 7) & 0x1;
	hdr->path_msg = (buf[idx] >> 6) & 0x1;
	hdr->msg_len = buf[idx] & 0x3f;
	idx++;
	hdr->somt = (buf[idx] >> 7) & 0x1;
	hdr->eomt = (buf[idx] >> 6) & 0x1;
	hdr->seqno = (buf[idx] >> 4) & 0x1;
	idx++;
	*hdrlen = idx;
	return true;
}
 
static void drm_dp_encode_sideband_req(struct drm_dp_sideband_msg_req_body *req,
				       struct drm_dp_sideband_msg_tx *raw)
{
	int idx = 0;
	int i;
	u8 *buf = raw->msg;
	buf[idx++] = req->req_type & 0x7f;
 
	switch (req->req_type) {
	case DP_ENUM_PATH_RESOURCES:
		buf[idx] = (req->u.port_num.port_number & 0xf) << 4;
		idx++;
		break;
	case DP_ALLOCATE_PAYLOAD:
		buf[idx] = (req->u.allocate_payload.port_number & 0xf) << 4 |
			(req->u.allocate_payload.number_sdp_streams & 0xf);
		idx++;
		buf[idx] = (req->u.allocate_payload.vcpi & 0x7f);
		idx++;
		buf[idx] = (req->u.allocate_payload.pbn >> 8);
		idx++;
		buf[idx] = (req->u.allocate_payload.pbn & 0xff);
		idx++;
		for (i = 0; i < req->u.allocate_payload.number_sdp_streams / 2; i++) {
			buf[idx] = ((req->u.allocate_payload.sdp_stream_sink[i * 2] & 0xf) << 4) |
				(req->u.allocate_payload.sdp_stream_sink[i * 2 + 1] & 0xf);
			idx++;
		}
		if (req->u.allocate_payload.number_sdp_streams & 1) {
			i = req->u.allocate_payload.number_sdp_streams - 1;
			buf[idx] = (req->u.allocate_payload.sdp_stream_sink[i] & 0xf) << 4;
			idx++;
		}
		break;
	case DP_QUERY_PAYLOAD:
		buf[idx] = (req->u.query_payload.port_number & 0xf) << 4;
		idx++;
		buf[idx] = (req->u.query_payload.vcpi & 0x7f);
		idx++;
		break;
	case DP_REMOTE_DPCD_READ:
		buf[idx] = (req->u.dpcd_read.port_number & 0xf) << 4;
		buf[idx] |= ((req->u.dpcd_read.dpcd_address & 0xf0000) >> 16) & 0xf;
		idx++;
		buf[idx] = (req->u.dpcd_read.dpcd_address & 0xff00) >> 8;
		idx++;
		buf[idx] = (req->u.dpcd_read.dpcd_address & 0xff);
		idx++;
		buf[idx] = (req->u.dpcd_read.num_bytes);
		idx++;
		break;
 
	case DP_REMOTE_DPCD_WRITE:
		buf[idx] = (req->u.dpcd_write.port_number & 0xf) << 4;
		buf[idx] |= ((req->u.dpcd_write.dpcd_address & 0xf0000) >> 16) & 0xf;
		idx++;
		buf[idx] = (req->u.dpcd_write.dpcd_address & 0xff00) >> 8;
		idx++;
		buf[idx] = (req->u.dpcd_write.dpcd_address & 0xff);
		idx++;
		buf[idx] = (req->u.dpcd_write.num_bytes);
		idx++;
		memcpy(&buf[idx], req->u.dpcd_write.bytes, req->u.dpcd_write.num_bytes);
		idx += req->u.dpcd_write.num_bytes;
		break;
	case DP_REMOTE_I2C_READ:
		buf[idx] = (req->u.i2c_read.port_number & 0xf) << 4;
		buf[idx] |= (req->u.i2c_read.num_transactions & 0x3);
		idx++;
		for (i = 0; i < (req->u.i2c_read.num_transactions & 0x3); i++) {
			buf[idx] = req->u.i2c_read.transactions[i].i2c_dev_id & 0x7f;
			idx++;
			buf[idx] = req->u.i2c_read.transactions[i].num_bytes;
			idx++;
			memcpy(&buf[idx], req->u.i2c_read.transactions[i].bytes, req->u.i2c_read.transactions[i].num_bytes);
			idx += req->u.i2c_read.transactions[i].num_bytes;
 
			buf[idx] = (req->u.i2c_read.transactions[i].no_stop_bit & 0x1) << 5;
			buf[idx] |= (req->u.i2c_read.transactions[i].i2c_transaction_delay & 0xf);
			idx++;
		}
		buf[idx] = (req->u.i2c_read.read_i2c_device_id) & 0x7f;
		idx++;
		buf[idx] = (req->u.i2c_read.num_bytes_read);
		idx++;
		break;
 
	case DP_REMOTE_I2C_WRITE:
		buf[idx] = (req->u.i2c_write.port_number & 0xf) << 4;
		idx++;
		buf[idx] = (req->u.i2c_write.write_i2c_device_id) & 0x7f;
		idx++;
		buf[idx] = (req->u.i2c_write.num_bytes);
		idx++;
		memcpy(&buf[idx], req->u.i2c_write.bytes, req->u.i2c_write.num_bytes);
		idx += req->u.i2c_write.num_bytes;
		break;
	}
	raw->cur_len = idx;
}
 
static void drm_dp_crc_sideband_chunk_req(u8 *msg, u8 len)
{
	u8 crc4;
	crc4 = drm_dp_msg_data_crc4(msg, len);
	msg[len] = crc4;
}
 
static void drm_dp_encode_sideband_reply(struct drm_dp_sideband_msg_reply_body *rep,
					 struct drm_dp_sideband_msg_tx *raw)
{
	int idx = 0;
	u8 *buf = raw->msg;
 
	buf[idx++] = (rep->reply_type & 0x1) << 7 | (rep->req_type & 0x7f);
 
	raw->cur_len = idx;
}
 
/* this adds a chunk of msg to the builder to get the final msg */
static bool drm_dp_sideband_msg_build(struct drm_dp_sideband_msg_rx *msg,
				      u8 *replybuf, u8 replybuflen, bool hdr)
{
	int ret;
	u8 crc4;
 
	if (hdr) {
		u8 hdrlen;
		struct drm_dp_sideband_msg_hdr recv_hdr;
		ret = drm_dp_decode_sideband_msg_hdr(&recv_hdr, replybuf, replybuflen, &hdrlen);
		if (ret == false) {
			print_hex_dump(KERN_DEBUG, "failed hdr", DUMP_PREFIX_NONE, 16, 1, replybuf, replybuflen, false);
			return false;
		}
 
		/* get length contained in this portion */
		msg->curchunk_len = recv_hdr.msg_len;
		msg->curchunk_hdrlen = hdrlen;
 
		/* we have already gotten an somt - don't bother parsing */
		if (recv_hdr.somt && msg->have_somt)
			return false;
 
		if (recv_hdr.somt) {
			memcpy(&msg->initial_hdr, &recv_hdr, sizeof(struct drm_dp_sideband_msg_hdr));
			msg->have_somt = true;
		}
		if (recv_hdr.eomt)
			msg->have_eomt = true;
 
		/* copy the bytes for the remainder of this header chunk */
		msg->curchunk_idx = min(msg->curchunk_len, (u8)(replybuflen - hdrlen));
		memcpy(&msg->chunk[0], replybuf + hdrlen, msg->curchunk_idx);
	} else {
		memcpy(&msg->chunk[msg->curchunk_idx], replybuf, replybuflen);
		msg->curchunk_idx += replybuflen;
	}
 
	if (msg->curchunk_idx >= msg->curchunk_len) {
		/* do CRC */
		crc4 = drm_dp_msg_data_crc4(msg->chunk, msg->curchunk_len - 1);
		/* copy chunk into bigger msg */
		memcpy(&msg->msg[msg->curlen], msg->chunk, msg->curchunk_len - 1);
		msg->curlen += msg->curchunk_len - 1;
	}
	return true;
}
 
static bool drm_dp_sideband_parse_link_address(struct drm_dp_sideband_msg_rx *raw,
					       struct drm_dp_sideband_msg_reply_body *repmsg)
{
	int idx = 1;
	int i;
	memcpy(repmsg->u.link_addr.guid, &raw->msg[idx], 16);
	idx += 16;
	repmsg->u.link_addr.nports = raw->msg[idx] & 0xf;
	idx++;
	if (idx > raw->curlen)
		goto fail_len;
	for (i = 0; i < repmsg->u.link_addr.nports; i++) {
		if (raw->msg[idx] & 0x80)
			repmsg->u.link_addr.ports[i].input_port = 1;
 
		repmsg->u.link_addr.ports[i].peer_device_type = (raw->msg[idx] >> 4) & 0x7;
		repmsg->u.link_addr.ports[i].port_number = (raw->msg[idx] & 0xf);
 
		idx++;
		if (idx > raw->curlen)
			goto fail_len;
		repmsg->u.link_addr.ports[i].mcs = (raw->msg[idx] >> 7) & 0x1;
		repmsg->u.link_addr.ports[i].ddps = (raw->msg[idx] >> 6) & 0x1;
		if (repmsg->u.link_addr.ports[i].input_port == 0)
			repmsg->u.link_addr.ports[i].legacy_device_plug_status = (raw->msg[idx] >> 5) & 0x1;
		idx++;
		if (idx > raw->curlen)
			goto fail_len;
		if (repmsg->u.link_addr.ports[i].input_port == 0) {
			repmsg->u.link_addr.ports[i].dpcd_revision = (raw->msg[idx]);
			idx++;
			if (idx > raw->curlen)
				goto fail_len;
			memcpy(repmsg->u.link_addr.ports[i].peer_guid, &raw->msg[idx], 16);
			idx += 16;
			if (idx > raw->curlen)
				goto fail_len;
			repmsg->u.link_addr.ports[i].num_sdp_streams = (raw->msg[idx] >> 4) & 0xf;
			repmsg->u.link_addr.ports[i].num_sdp_stream_sinks = (raw->msg[idx] & 0xf);
			idx++;
 
		}
		if (idx > raw->curlen)
			goto fail_len;
	}
 
	return true;
fail_len:
	DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx, raw->curlen);
	return false;
}
 
static bool drm_dp_sideband_parse_remote_dpcd_read(struct drm_dp_sideband_msg_rx *raw,
						   struct drm_dp_sideband_msg_reply_body *repmsg)
{
	int idx = 1;
	repmsg->u.remote_dpcd_read_ack.port_number = raw->msg[idx] & 0xf;
	idx++;
	if (idx > raw->curlen)
		goto fail_len;
	repmsg->u.remote_dpcd_read_ack.num_bytes = raw->msg[idx];
	if (idx > raw->curlen)
		goto fail_len;
 
	memcpy(repmsg->u.remote_dpcd_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_dpcd_read_ack.num_bytes);
	return true;
fail_len:
	DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx, raw->curlen);
	return false;
}
 
static bool drm_dp_sideband_parse_remote_dpcd_write(struct drm_dp_sideband_msg_rx *raw,
						      struct drm_dp_sideband_msg_reply_body *repmsg)
{
	int idx = 1;
	repmsg->u.remote_dpcd_write_ack.port_number = raw->msg[idx] & 0xf;
	idx++;
	if (idx > raw->curlen)
		goto fail_len;
	return true;
fail_len:
	DRM_DEBUG_KMS("parse length fail %d %d\n", idx, raw->curlen);
	return false;
}
 
static bool drm_dp_sideband_parse_remote_i2c_read_ack(struct drm_dp_sideband_msg_rx *raw,
						      struct drm_dp_sideband_msg_reply_body *repmsg)
{
	int idx = 1;
 
	repmsg->u.remote_i2c_read_ack.port_number = (raw->msg[idx] & 0xf);
	idx++;
	if (idx > raw->curlen)
		goto fail_len;
	repmsg->u.remote_i2c_read_ack.num_bytes = raw->msg[idx];
	idx++;
	/* TODO check */
	memcpy(repmsg->u.remote_i2c_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_i2c_read_ack.num_bytes);
	return true;
fail_len:
	DRM_DEBUG_KMS("remote i2c reply parse length fail %d %d\n", idx, raw->curlen);
	return false;
}
 
static bool drm_dp_sideband_parse_enum_path_resources_ack(struct drm_dp_sideband_msg_rx *raw,
							  struct drm_dp_sideband_msg_reply_body *repmsg)
{
	int idx = 1;
	repmsg->u.path_resources.port_number = (raw->msg[idx] >> 4) & 0xf;
	idx++;
	if (idx > raw->curlen)
		goto fail_len;
	repmsg->u.path_resources.full_payload_bw_number = (raw->msg[idx] << 8) | (raw->msg[idx+1]);
	idx += 2;
	if (idx > raw->curlen)
		goto fail_len;
	repmsg->u.path_resources.avail_payload_bw_number = (raw->msg[idx] << 8) | (raw->msg[idx+1]);
	idx += 2;
	if (idx > raw->curlen)
		goto fail_len;
	return true;
fail_len:
	DRM_DEBUG_KMS("enum resource parse length fail %d %d\n", idx, raw->curlen);
	return false;
}
 
static bool drm_dp_sideband_parse_allocate_payload_ack(struct drm_dp_sideband_msg_rx *raw,
							  struct drm_dp_sideband_msg_reply_body *repmsg)
{
	int idx = 1;
	repmsg->u.allocate_payload.port_number = (raw->msg[idx] >> 4) & 0xf;
	idx++;
	if (idx > raw->curlen)
		goto fail_len;
	repmsg->u.allocate_payload.vcpi = raw->msg[idx];
	idx++;
	if (idx > raw->curlen)
		goto fail_len;
	repmsg->u.allocate_payload.allocated_pbn = (raw->msg[idx] << 8) | (raw->msg[idx+1]);
	idx += 2;
	if (idx > raw->curlen)
		goto fail_len;
	return true;
fail_len:
	DRM_DEBUG_KMS("allocate payload parse length fail %d %d\n", idx, raw->curlen);
	return false;
}
 
static bool drm_dp_sideband_parse_query_payload_ack(struct drm_dp_sideband_msg_rx *raw,
						    struct drm_dp_sideband_msg_reply_body *repmsg)
{
	int idx = 1;
	repmsg->u.query_payload.port_number = (raw->msg[idx] >> 4) & 0xf;
	idx++;
	if (idx > raw->curlen)
		goto fail_len;
	repmsg->u.query_payload.allocated_pbn = (raw->msg[idx] << 8) | (raw->msg[idx + 1]);
	idx += 2;
	if (idx > raw->curlen)
		goto fail_len;
	return true;
fail_len:
	DRM_DEBUG_KMS("query payload parse length fail %d %d\n", idx, raw->curlen);
	return false;
}
 
static bool drm_dp_sideband_parse_reply(struct drm_dp_sideband_msg_rx *raw,
					struct drm_dp_sideband_msg_reply_body *msg)
{
	memset(msg, 0, sizeof(*msg));
	msg->reply_type = (raw->msg[0] & 0x80) >> 7;
	msg->req_type = (raw->msg[0] & 0x7f);
 
	if (msg->reply_type) {
		memcpy(msg->u.nak.guid, &raw->msg[1], 16);
		msg->u.nak.reason = raw->msg[17];
		msg->u.nak.nak_data = raw->msg[18];
		return false;
	}
 
	switch (msg->req_type) {
	case DP_LINK_ADDRESS:
		return drm_dp_sideband_parse_link_address(raw, msg);
	case DP_QUERY_PAYLOAD:
		return drm_dp_sideband_parse_query_payload_ack(raw, msg);
	case DP_REMOTE_DPCD_READ:
		return drm_dp_sideband_parse_remote_dpcd_read(raw, msg);
	case DP_REMOTE_DPCD_WRITE:
		return drm_dp_sideband_parse_remote_dpcd_write(raw, msg);
	case DP_REMOTE_I2C_READ:
		return drm_dp_sideband_parse_remote_i2c_read_ack(raw, msg);
	case DP_ENUM_PATH_RESOURCES:
		return drm_dp_sideband_parse_enum_path_resources_ack(raw, msg);
	case DP_ALLOCATE_PAYLOAD:
		return drm_dp_sideband_parse_allocate_payload_ack(raw, msg);
	default:
		DRM_ERROR("Got unknown reply 0x%02x\n", msg->req_type);
		return false;
	}
}
 
static bool drm_dp_sideband_parse_connection_status_notify(struct drm_dp_sideband_msg_rx *raw,
							   struct drm_dp_sideband_msg_req_body *msg)
{
	int idx = 1;
 
	msg->u.conn_stat.port_number = (raw->msg[idx] & 0xf0) >> 4;
	idx++;
	if (idx > raw->curlen)
		goto fail_len;
 
	memcpy(msg->u.conn_stat.guid, &raw->msg[idx], 16);
	idx += 16;
	if (idx > raw->curlen)
		goto fail_len;
 
	msg->u.conn_stat.legacy_device_plug_status = (raw->msg[idx] >> 6) & 0x1;
	msg->u.conn_stat.displayport_device_plug_status = (raw->msg[idx] >> 5) & 0x1;
	msg->u.conn_stat.message_capability_status = (raw->msg[idx] >> 4) & 0x1;
	msg->u.conn_stat.input_port = (raw->msg[idx] >> 3) & 0x1;
	msg->u.conn_stat.peer_device_type = (raw->msg[idx] & 0x7);
	idx++;
	return true;
fail_len:
	DRM_DEBUG_KMS("connection status reply parse length fail %d %d\n", idx, raw->curlen);
	return false;
}
 
static bool drm_dp_sideband_parse_resource_status_notify(struct drm_dp_sideband_msg_rx *raw,
							   struct drm_dp_sideband_msg_req_body *msg)
{
	int idx = 1;
 
	msg->u.resource_stat.port_number = (raw->msg[idx] & 0xf0) >> 4;
	idx++;
	if (idx > raw->curlen)
		goto fail_len;
 
	memcpy(msg->u.resource_stat.guid, &raw->msg[idx], 16);
	idx += 16;
	if (idx > raw->curlen)
		goto fail_len;
 
	msg->u.resource_stat.available_pbn = (raw->msg[idx] << 8) | (raw->msg[idx + 1]);
	idx++;
	return true;
fail_len:
	DRM_DEBUG_KMS("resource status reply parse length fail %d %d\n", idx, raw->curlen);
	return false;
}
 
static bool drm_dp_sideband_parse_req(struct drm_dp_sideband_msg_rx *raw,
				      struct drm_dp_sideband_msg_req_body *msg)
{
	memset(msg, 0, sizeof(*msg));
	msg->req_type = (raw->msg[0] & 0x7f);
 
	switch (msg->req_type) {
	case DP_CONNECTION_STATUS_NOTIFY:
		return drm_dp_sideband_parse_connection_status_notify(raw, msg);
	case DP_RESOURCE_STATUS_NOTIFY:
		return drm_dp_sideband_parse_resource_status_notify(raw, msg);
	default:
		DRM_ERROR("Got unknown request 0x%02x\n", msg->req_type);
		return false;
	}
}
 
static int build_dpcd_write(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes, u8 *bytes)
{
	struct drm_dp_sideband_msg_req_body req;
 
	req.req_type = DP_REMOTE_DPCD_WRITE;
	req.u.dpcd_write.port_number = port_num;
	req.u.dpcd_write.dpcd_address = offset;
	req.u.dpcd_write.num_bytes = num_bytes;
	req.u.dpcd_write.bytes = bytes;
	drm_dp_encode_sideband_req(&req, msg);
 
	return 0;
}
 
static int build_link_address(struct drm_dp_sideband_msg_tx *msg)
{
	struct drm_dp_sideband_msg_req_body req;
 
	req.req_type = DP_LINK_ADDRESS;
	drm_dp_encode_sideband_req(&req, msg);
	return 0;
}
 
static int build_enum_path_resources(struct drm_dp_sideband_msg_tx *msg, int port_num)
{
	struct drm_dp_sideband_msg_req_body req;
 
	req.req_type = DP_ENUM_PATH_RESOURCES;
	req.u.port_num.port_number = port_num;
	drm_dp_encode_sideband_req(&req, msg);
	msg->path_msg = true;
	return 0;
}
 
static int build_allocate_payload(struct drm_dp_sideband_msg_tx *msg, int port_num,
				  u8 vcpi, uint16_t pbn)
{
	struct drm_dp_sideband_msg_req_body req;
	memset(&req, 0, sizeof(req));
	req.req_type = DP_ALLOCATE_PAYLOAD;
	req.u.allocate_payload.port_number = port_num;
	req.u.allocate_payload.vcpi = vcpi;
	req.u.allocate_payload.pbn = pbn;
	drm_dp_encode_sideband_req(&req, msg);
	msg->path_msg = true;
	return 0;
}
 
static int drm_dp_mst_assign_payload_id(struct drm_dp_mst_topology_mgr *mgr,
					struct drm_dp_vcpi *vcpi)
{
	int ret, vcpi_ret;
 
	mutex_lock(&mgr->payload_lock);
	ret = find_first_zero_bit(&mgr->payload_mask, mgr->max_payloads + 1);
	if (ret > mgr->max_payloads) {
		ret = -EINVAL;
		DRM_DEBUG_KMS("out of payload ids %d\n", ret);
		goto out_unlock;
	}
 
	vcpi_ret = find_first_zero_bit(&mgr->vcpi_mask, mgr->max_payloads + 1);
	if (vcpi_ret > mgr->max_payloads) {
		ret = -EINVAL;
		DRM_DEBUG_KMS("out of vcpi ids %d\n", ret);
		goto out_unlock;
	}
 
	set_bit(ret, &mgr->payload_mask);
	set_bit(vcpi_ret, &mgr->vcpi_mask);
	vcpi->vcpi = vcpi_ret + 1;
	mgr->proposed_vcpis[ret - 1] = vcpi;
out_unlock:
	mutex_unlock(&mgr->payload_lock);
	return ret;
}
 
static void drm_dp_mst_put_payload_id(struct drm_dp_mst_topology_mgr *mgr,
				      int vcpi)
{
	int i;
	if (vcpi == 0)
		return;
 
	mutex_lock(&mgr->payload_lock);
	DRM_DEBUG_KMS("putting payload %d\n", vcpi);
	clear_bit(vcpi - 1, &mgr->vcpi_mask);
 
	for (i = 0; i < mgr->max_payloads; i++) {
		if (mgr->proposed_vcpis[i])
			if (mgr->proposed_vcpis[i]->vcpi == vcpi) {
				mgr->proposed_vcpis[i] = NULL;
				clear_bit(i + 1, &mgr->payload_mask);
			}
	}
	mutex_unlock(&mgr->payload_lock);
}
 
static bool check_txmsg_state(struct drm_dp_mst_topology_mgr *mgr,
			      struct drm_dp_sideband_msg_tx *txmsg)
{
	bool ret;
 
	/*
	 * All updates to txmsg->state are protected by mgr->qlock, and the two
	 * cases we check here are terminal states. For those the barriers
	 * provided by the wake_up/wait_event pair are enough.
	 */
	ret = (txmsg->state == DRM_DP_SIDEBAND_TX_RX ||
	       txmsg->state == DRM_DP_SIDEBAND_TX_TIMEOUT);
	return ret;
}
 
static int drm_dp_mst_wait_tx_reply(struct drm_dp_mst_branch *mstb,
				    struct drm_dp_sideband_msg_tx *txmsg)
{
	struct drm_dp_mst_topology_mgr *mgr = mstb->mgr;
	int ret;
 
	ret = wait_event_timeout(mgr->tx_waitq,
				 check_txmsg_state(mgr, txmsg),
				 (4 * HZ));
	mutex_lock(&mstb->mgr->qlock);
	if (ret > 0) {
		if (txmsg->state == DRM_DP_SIDEBAND_TX_TIMEOUT) {
			ret = -EIO;
			goto out;
		}
	} else {
		DRM_DEBUG_KMS("timedout msg send %p %d %d\n", txmsg, txmsg->state, txmsg->seqno);
 
		/* dump some state */
		ret = -EIO;
 
		/* remove from q */
		if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED ||
		    txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND) {
			list_del(&txmsg->next);
		}
 
		if (txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND ||
		    txmsg->state == DRM_DP_SIDEBAND_TX_SENT) {
			mstb->tx_slots[txmsg->seqno] = NULL;
		}
	}
out:
	mutex_unlock(&mgr->qlock);
 
	return ret;
}
 
static struct drm_dp_mst_branch *drm_dp_add_mst_branch_device(u8 lct, u8 *rad)
{
	struct drm_dp_mst_branch *mstb;
 
	mstb = kzalloc(sizeof(*mstb), GFP_KERNEL);
	if (!mstb)
		return NULL;
 
	mstb->lct = lct;
	if (lct > 1)
		memcpy(mstb->rad, rad, lct / 2);
	INIT_LIST_HEAD(&mstb->ports);
	kref_init(&mstb->kref);
	return mstb;
}
 
static void drm_dp_free_mst_port(struct kref *kref);
 
static void drm_dp_free_mst_branch_device(struct kref *kref)
{
	struct drm_dp_mst_branch *mstb = container_of(kref, struct drm_dp_mst_branch, kref);
	if (mstb->port_parent) {
		if (list_empty(&mstb->port_parent->next))
			kref_put(&mstb->port_parent->kref, drm_dp_free_mst_port);
	}
	kfree(mstb);
}
 
static void drm_dp_destroy_mst_branch_device(struct kref *kref)
{
	struct drm_dp_mst_branch *mstb = container_of(kref, struct drm_dp_mst_branch, kref);
	struct drm_dp_mst_port *port, *tmp;
	bool wake_tx = false;
 
	/*
	 * init kref again to be used by ports to remove mst branch when it is
	 * not needed anymore
	 */
	kref_init(kref);
 
	if (mstb->port_parent && list_empty(&mstb->port_parent->next))
		kref_get(&mstb->port_parent->kref);
 
	/*
	 * destroy all ports - don't need lock
	 * as there are no more references to the mst branch
	 * device at this point.
	 */
	list_for_each_entry_safe(port, tmp, &mstb->ports, next) {
		list_del(&port->next);
		drm_dp_put_port(port);
	}
 
	/* drop any tx slots msg */
	mutex_lock(&mstb->mgr->qlock);
	if (mstb->tx_slots[0]) {
		mstb->tx_slots[0]->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
		mstb->tx_slots[0] = NULL;
		wake_tx = true;
	}
	if (mstb->tx_slots[1]) {
		mstb->tx_slots[1]->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
		mstb->tx_slots[1] = NULL;
		wake_tx = true;
	}
	mutex_unlock(&mstb->mgr->qlock);
 
//   if (wake_tx)
//       wake_up(&mstb->mgr->tx_waitq);
	kref_put(kref, drm_dp_free_mst_branch_device);
}
 
static void drm_dp_put_mst_branch_device(struct drm_dp_mst_branch *mstb)
{
	kref_put(&mstb->kref, drm_dp_destroy_mst_branch_device);
}
 
 
static void drm_dp_port_teardown_pdt(struct drm_dp_mst_port *port, int old_pdt)
{
	struct drm_dp_mst_branch *mstb;
 
	switch (old_pdt) {
	case DP_PEER_DEVICE_DP_LEGACY_CONV:
	case DP_PEER_DEVICE_SST_SINK:
		/* remove i2c over sideband */
		drm_dp_mst_unregister_i2c_bus(&port->aux);
		break;
	case DP_PEER_DEVICE_MST_BRANCHING:
		mstb = port->mstb;
		port->mstb = NULL;
		drm_dp_put_mst_branch_device(mstb);
		break;
	}
}
 
static void drm_dp_destroy_port(struct kref *kref)
{
	struct drm_dp_mst_port *port = container_of(kref, struct drm_dp_mst_port, kref);
	struct drm_dp_mst_topology_mgr *mgr = port->mgr;
 
	if (!port->input) {
		port->vcpi.num_slots = 0;
 
		kfree(port->cached_edid);
 
		/*
		 * The only time we don't have a connector
		 * on an output port is if the connector init
		 * fails.
		 */
		if (port->connector) {
			/* we can't destroy the connector here, as
			 * we might be holding the mode_config.mutex
			 * from an EDID retrieval */
 
			mutex_lock(&mgr->destroy_connector_lock);
			kref_get(&port->parent->kref);
			list_add(&port->next, &mgr->destroy_connector_list);
			mutex_unlock(&mgr->destroy_connector_lock);
//		schedule_work(&mgr->destroy_connector_work);
			return;
		}
		/* no need to clean up vcpi
		 * as if we have no connector we never setup a vcpi */
		drm_dp_port_teardown_pdt(port, port->pdt);
	}
	kfree(port);
}
 
static void drm_dp_put_port(struct drm_dp_mst_port *port)
{
	kref_put(&port->kref, drm_dp_destroy_port);
}
 
static struct drm_dp_mst_branch *drm_dp_mst_get_validated_mstb_ref_locked(struct drm_dp_mst_branch *mstb, struct drm_dp_mst_branch *to_find)
{
	struct drm_dp_mst_port *port;
	struct drm_dp_mst_branch *rmstb;
	if (to_find == mstb) {
		kref_get(&mstb->kref);
		return mstb;
	}
	list_for_each_entry(port, &mstb->ports, next) {
		if (port->mstb) {
			rmstb = drm_dp_mst_get_validated_mstb_ref_locked(port->mstb, to_find);
			if (rmstb)
				return rmstb;
		}
	}
	return NULL;
}
 
static struct drm_dp_mst_branch *drm_dp_get_validated_mstb_ref(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_branch *mstb)
{
	struct drm_dp_mst_branch *rmstb = NULL;
	mutex_lock(&mgr->lock);
	if (mgr->mst_primary)
		rmstb = drm_dp_mst_get_validated_mstb_ref_locked(mgr->mst_primary, mstb);
	mutex_unlock(&mgr->lock);
	return rmstb;
}
 
static struct drm_dp_mst_port *drm_dp_mst_get_port_ref_locked(struct drm_dp_mst_branch *mstb, struct drm_dp_mst_port *to_find)
{
	struct drm_dp_mst_port *port, *mport;
 
	list_for_each_entry(port, &mstb->ports, next) {
		if (port == to_find) {
			kref_get(&port->kref);
			return port;
		}
		if (port->mstb) {
			mport = drm_dp_mst_get_port_ref_locked(port->mstb, to_find);
			if (mport)
				return mport;
		}
	}
	return NULL;
}
 
static struct drm_dp_mst_port *drm_dp_get_validated_port_ref(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
{
	struct drm_dp_mst_port *rport = NULL;
	mutex_lock(&mgr->lock);
	if (mgr->mst_primary)
		rport = drm_dp_mst_get_port_ref_locked(mgr->mst_primary, port);
	mutex_unlock(&mgr->lock);
	return rport;
}
 
static struct drm_dp_mst_port *drm_dp_get_port(struct drm_dp_mst_branch *mstb, u8 port_num)
{
	struct drm_dp_mst_port *port;
 
	list_for_each_entry(port, &mstb->ports, next) {
		if (port->port_num == port_num) {
			kref_get(&port->kref);
			return port;
		}
	}
 
	return NULL;
}
 
/*
 * calculate a new RAD for this MST branch device
 * if parent has an LCT of 2 then it has 1 nibble of RAD,
 * if parent has an LCT of 3 then it has 2 nibbles of RAD,
 */
static u8 drm_dp_calculate_rad(struct drm_dp_mst_port *port,
				 u8 *rad)
{
	int parent_lct = port->parent->lct;
	int shift = 4;
	int idx = (parent_lct - 1) / 2;
	if (parent_lct > 1) {
		memcpy(rad, port->parent->rad, idx + 1);
		shift = (parent_lct % 2) ? 4 : 0;
	} else
		rad[0] = 0;
 
	rad[idx] |= port->port_num << shift;
	return parent_lct + 1;
}
 
/*
 * return sends link address for new mstb
 */
static bool drm_dp_port_setup_pdt(struct drm_dp_mst_port *port)
{
	int ret;
	u8 rad[6], lct;
	bool send_link = false;
	switch (port->pdt) {
	case DP_PEER_DEVICE_DP_LEGACY_CONV:
	case DP_PEER_DEVICE_SST_SINK:
		/* add i2c over sideband */
		ret = drm_dp_mst_register_i2c_bus(&port->aux);
		break;
	case DP_PEER_DEVICE_MST_BRANCHING:
		lct = drm_dp_calculate_rad(port, rad);
 
		port->mstb = drm_dp_add_mst_branch_device(lct, rad);
		port->mstb->mgr = port->mgr;
		port->mstb->port_parent = port;
 
		send_link = true;
		break;
	}
	return send_link;
}
 
static void drm_dp_check_mstb_guid(struct drm_dp_mst_branch *mstb, u8 *guid)
{
	int ret;
 
	memcpy(mstb->guid, guid, 16);
 
	if (!drm_dp_validate_guid(mstb->mgr, mstb->guid)) {
		if (mstb->port_parent) {
			ret = drm_dp_send_dpcd_write(
					mstb->mgr,
					mstb->port_parent,
					DP_GUID,
					16,
					mstb->guid);
		} else {
 
			ret = drm_dp_dpcd_write(
					mstb->mgr->aux,
						     DP_GUID,
					mstb->guid,
					16);
		}
	}
}
 
static void build_mst_prop_path(const struct drm_dp_mst_branch *mstb,
				int pnum,
				char *proppath,
				size_t proppath_size)
{
	int i;
	char temp[8];
	snprintf(proppath, proppath_size, "mst:%d", mstb->mgr->conn_base_id);
	for (i = 0; i < (mstb->lct - 1); i++) {
		int shift = (i % 2) ? 0 : 4;
		int port_num = (mstb->rad[i / 2] >> shift) & 0xf;
		snprintf(temp, sizeof(temp), "-%d", port_num);
		strlcat(proppath, temp, proppath_size);
	}
	snprintf(temp, sizeof(temp), "-%d", pnum);
	strlcat(proppath, temp, proppath_size);
}
 
static void drm_dp_add_port(struct drm_dp_mst_branch *mstb,
			    struct device *dev,
			    struct drm_dp_link_addr_reply_port *port_msg)
{
	struct drm_dp_mst_port *port;
	bool ret;
	bool created = false;
	int old_pdt = 0;
	int old_ddps = 0;
	port = drm_dp_get_port(mstb, port_msg->port_number);
	if (!port) {
		port = kzalloc(sizeof(*port), GFP_KERNEL);
		if (!port)
			return;
		kref_init(&port->kref);
		port->parent = mstb;
		port->port_num = port_msg->port_number;
		port->mgr = mstb->mgr;
		port->aux.name = "DPMST";
		port->aux.dev = dev;
		created = true;
	} else {
		old_pdt = port->pdt;
		old_ddps = port->ddps;
	}
 
	port->pdt = port_msg->peer_device_type;
	port->input = port_msg->input_port;
	port->mcs = port_msg->mcs;
	port->ddps = port_msg->ddps;
	port->ldps = port_msg->legacy_device_plug_status;
	port->dpcd_rev = port_msg->dpcd_revision;
	port->num_sdp_streams = port_msg->num_sdp_streams;
	port->num_sdp_stream_sinks = port_msg->num_sdp_stream_sinks;
 
	/* manage mstb port lists with mgr lock - take a reference
	   for this list */
	if (created) {
		mutex_lock(&mstb->mgr->lock);
		kref_get(&port->kref);
		list_add(&port->next, &mstb->ports);
		mutex_unlock(&mstb->mgr->lock);
	}
 
	if (old_ddps != port->ddps) {
		if (port->ddps) {
			if (!port->input)
				drm_dp_send_enum_path_resources(mstb->mgr, mstb, port);
		} else {
			port->available_pbn = 0;
			}
	}
 
	if (old_pdt != port->pdt && !port->input) {
		drm_dp_port_teardown_pdt(port, old_pdt);
 
		ret = drm_dp_port_setup_pdt(port);
		if (ret == true)
			drm_dp_send_link_address(mstb->mgr, port->mstb);
	}
 
	if (created && !port->input) {
		char proppath[255];
 
		build_mst_prop_path(mstb, port->port_num, proppath, sizeof(proppath));
		port->connector = (*mstb->mgr->cbs->add_connector)(mstb->mgr, port, proppath);
		if (!port->connector) {
			/* remove it from the port list */
			mutex_lock(&mstb->mgr->lock);
			list_del(&port->next);
			mutex_unlock(&mstb->mgr->lock);
			/* drop port list reference */
			drm_dp_put_port(port);
			goto out;
		}
		if (port->port_num >= DP_MST_LOGICAL_PORT_0) {
			port->cached_edid = drm_get_edid(port->connector, &port->aux.ddc);
			drm_mode_connector_set_tile_property(port->connector);
		}
		(*mstb->mgr->cbs->register_connector)(port->connector);
	}
 
out:
	/* put reference to this port */
	drm_dp_put_port(port);
}
 
static void drm_dp_update_port(struct drm_dp_mst_branch *mstb,
			       struct drm_dp_connection_status_notify *conn_stat)
{
	struct drm_dp_mst_port *port;
	int old_pdt;
	int old_ddps;
	bool dowork = false;
	port = drm_dp_get_port(mstb, conn_stat->port_number);
	if (!port)
		return;
 
	old_ddps = port->ddps;
	old_pdt = port->pdt;
	port->pdt = conn_stat->peer_device_type;
	port->mcs = conn_stat->message_capability_status;
	port->ldps = conn_stat->legacy_device_plug_status;
	port->ddps = conn_stat->displayport_device_plug_status;
 
	if (old_ddps != port->ddps) {
		if (port->ddps) {
			dowork = true;
		} else {
			port->available_pbn = 0;
		}
	}
	if (old_pdt != port->pdt && !port->input) {
		drm_dp_port_teardown_pdt(port, old_pdt);
 
		if (drm_dp_port_setup_pdt(port))
			dowork = true;
	}
 
	drm_dp_put_port(port);
//   if (dowork)
//       queue_work(system_long_wq, &mstb->mgr->work);
 
}
 
static struct drm_dp_mst_branch *drm_dp_get_mst_branch_device(struct drm_dp_mst_topology_mgr *mgr,
							       u8 lct, u8 *rad)
{
	struct drm_dp_mst_branch *mstb;
	struct drm_dp_mst_port *port;
	int i;
	/* find the port by iterating down */
 
	mutex_lock(&mgr->lock);
	mstb = mgr->mst_primary;
 
	for (i = 0; i < lct - 1; i++) {
		int shift = (i % 2) ? 0 : 4;
		int port_num = (rad[i / 2] >> shift) & 0xf;
 
		list_for_each_entry(port, &mstb->ports, next) {
			if (port->port_num == port_num) {
				mstb = port->mstb;
				if (!mstb) {
					DRM_ERROR("failed to lookup MSTB with lct %d, rad %02x\n", lct, rad[0]);
					goto out;
				}
 
				break;
			}
		}
	}
	kref_get(&mstb->kref);
out:
	mutex_unlock(&mgr->lock);
	return mstb;
}
 
static struct drm_dp_mst_branch *get_mst_branch_device_by_guid_helper(
	struct drm_dp_mst_branch *mstb,
	uint8_t *guid)
{
	struct drm_dp_mst_branch *found_mstb;
	struct drm_dp_mst_port *port;
 
	if (memcmp(mstb->guid, guid, 16) == 0)
		return mstb;
 
 
	list_for_each_entry(port, &mstb->ports, next) {
		if (!port->mstb)
			continue;
 
		found_mstb = get_mst_branch_device_by_guid_helper(port->mstb, guid);
 
		if (found_mstb)
			return found_mstb;
	}
 
	return NULL;
}
 
static struct drm_dp_mst_branch *drm_dp_get_mst_branch_device_by_guid(
	struct drm_dp_mst_topology_mgr *mgr,
	uint8_t *guid)
{
	struct drm_dp_mst_branch *mstb;
 
	/* find the port by iterating down */
	mutex_lock(&mgr->lock);
 
	mstb = get_mst_branch_device_by_guid_helper(mgr->mst_primary, guid);
 
	if (mstb)
		kref_get(&mstb->kref);
 
	mutex_unlock(&mgr->lock);
	return mstb;
}
 
static void drm_dp_check_and_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
					       struct drm_dp_mst_branch *mstb)
{
	struct drm_dp_mst_port *port;
	struct drm_dp_mst_branch *mstb_child;
	if (!mstb->link_address_sent)
		drm_dp_send_link_address(mgr, mstb);
 
	list_for_each_entry(port, &mstb->ports, next) {
		if (port->input)
			continue;
 
		if (!port->ddps)
			continue;
 
		if (!port->available_pbn)
			drm_dp_send_enum_path_resources(mgr, mstb, port);
 
		if (port->mstb) {
			mstb_child = drm_dp_get_validated_mstb_ref(mgr, port->mstb);
			if (mstb_child) {
				drm_dp_check_and_send_link_address(mgr, mstb_child);
				drm_dp_put_mst_branch_device(mstb_child);
			}
		}
	}
}
 
static void drm_dp_mst_link_probe_work(struct work_struct *work)
{
	struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, work);
	struct drm_dp_mst_branch *mstb;
 
	mutex_lock(&mgr->lock);
	mstb = mgr->mst_primary;
	if (mstb) {
		kref_get(&mstb->kref);
	}
	mutex_unlock(&mgr->lock);
	if (mstb) {
		drm_dp_check_and_send_link_address(mgr, mstb);
		drm_dp_put_mst_branch_device(mstb);
	}
}
 
static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr,
				 u8 *guid)
{
	static u8 zero_guid[16];
 
	if (!memcmp(guid, zero_guid, 16)) {
		u64 salt = get_jiffies_64();
		memcpy(&guid[0], &salt, sizeof(u64));
		memcpy(&guid[8], &salt, sizeof(u64));
		return false;
	}
	return true;
}
 
#if 0
static int build_dpcd_read(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes)
{
	struct drm_dp_sideband_msg_req_body req;
 
	req.req_type = DP_REMOTE_DPCD_READ;
	req.u.dpcd_read.port_number = port_num;
	req.u.dpcd_read.dpcd_address = offset;
	req.u.dpcd_read.num_bytes = num_bytes;
	drm_dp_encode_sideband_req(&req, msg);
 
	return 0;
}
#endif
 
static int drm_dp_send_sideband_msg(struct drm_dp_mst_topology_mgr *mgr,
				    bool up, u8 *msg, int len)
{
	int ret;
	int regbase = up ? DP_SIDEBAND_MSG_UP_REP_BASE : DP_SIDEBAND_MSG_DOWN_REQ_BASE;
	int tosend, total, offset;
	int retries = 0;
 
retry:
	total = len;
	offset = 0;
	do {
		tosend = min3(mgr->max_dpcd_transaction_bytes, 16, total);
 
		ret = drm_dp_dpcd_write(mgr->aux, regbase + offset,
					&msg[offset],
					tosend);
		if (ret != tosend) {
			if (ret == -EIO && retries < 5) {
				retries++;
				goto retry;
			}
			DRM_DEBUG_KMS("failed to dpcd write %d %d\n", tosend, ret);
 
			return -EIO;
		}
		offset += tosend;
		total -= tosend;
	} while (total > 0);
	return 0;
}
 
static int set_hdr_from_dst_qlock(struct drm_dp_sideband_msg_hdr *hdr,
				  struct drm_dp_sideband_msg_tx *txmsg)
{
	struct drm_dp_mst_branch *mstb = txmsg->dst;
	u8 req_type;
 
	/* both msg slots are full */
	if (txmsg->seqno == -1) {
		if (mstb->tx_slots[0] && mstb->tx_slots[1]) {
			DRM_DEBUG_KMS("%s: failed to find slot\n", __func__);
			return -EAGAIN;
		}
		if (mstb->tx_slots[0] == NULL && mstb->tx_slots[1] == NULL) {
			txmsg->seqno = mstb->last_seqno;
			mstb->last_seqno ^= 1;
		} else if (mstb->tx_slots[0] == NULL)
			txmsg->seqno = 0;
		else
			txmsg->seqno = 1;
		mstb->tx_slots[txmsg->seqno] = txmsg;
	}
 
	req_type = txmsg->msg[0] & 0x7f;
	if (req_type == DP_CONNECTION_STATUS_NOTIFY ||
		req_type == DP_RESOURCE_STATUS_NOTIFY)
		hdr->broadcast = 1;
	else
	hdr->broadcast = 0;
	hdr->path_msg = txmsg->path_msg;
	hdr->lct = mstb->lct;
	hdr->lcr = mstb->lct - 1;
	if (mstb->lct > 1)
		memcpy(hdr->rad, mstb->rad, mstb->lct / 2);
	hdr->seqno = txmsg->seqno;
	return 0;
}
/*
 * process a single block of the next message in the sideband queue
 */
static int process_single_tx_qlock(struct drm_dp_mst_topology_mgr *mgr,
				   struct drm_dp_sideband_msg_tx *txmsg,
				   bool up)
{
	u8 chunk[48];
	struct drm_dp_sideband_msg_hdr hdr;
	int len, space, idx, tosend;
	int ret;
 
	memset(&hdr, 0, sizeof(struct drm_dp_sideband_msg_hdr));
 
	if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED) {
		txmsg->seqno = -1;
		txmsg->state = DRM_DP_SIDEBAND_TX_START_SEND;
	}
 
	/* make hdr from dst mst - for replies use seqno
	   otherwise assign one */
	ret = set_hdr_from_dst_qlock(&hdr, txmsg);
	if (ret < 0)
		return ret;
 
	/* amount left to send in this message */
	len = txmsg->cur_len - txmsg->cur_offset;
 
	/* 48 - sideband msg size - 1 byte for data CRC, x header bytes */
	space = 48 - 1 - drm_dp_calc_sb_hdr_size(&hdr);
 
	tosend = min(len, space);
	if (len == txmsg->cur_len)
		hdr.somt = 1;
	if (space >= len)
		hdr.eomt = 1;
 
 
	hdr.msg_len = tosend + 1;
	drm_dp_encode_sideband_msg_hdr(&hdr, chunk, &idx);
	memcpy(&chunk[idx], &txmsg->msg[txmsg->cur_offset], tosend);
	/* add crc at end */
	drm_dp_crc_sideband_chunk_req(&chunk[idx], tosend);
	idx += tosend + 1;
 
	ret = drm_dp_send_sideband_msg(mgr, up, chunk, idx);
	if (ret) {
		DRM_DEBUG_KMS("sideband msg failed to send\n");
		return ret;
	}
 
	txmsg->cur_offset += tosend;
	if (txmsg->cur_offset == txmsg->cur_len) {
		txmsg->state = DRM_DP_SIDEBAND_TX_SENT;
		return 1;
	}
	return 0;
}
 
static void process_single_down_tx_qlock(struct drm_dp_mst_topology_mgr *mgr)
{
	struct drm_dp_sideband_msg_tx *txmsg;
	int ret;
 
	WARN_ON(!mutex_is_locked(&mgr->qlock));
 
	/* construct a chunk from the first msg in the tx_msg queue */
	if (list_empty(&mgr->tx_msg_downq)) {
		mgr->tx_down_in_progress = false;
		return;
	}
	mgr->tx_down_in_progress = true;
 
	txmsg = list_first_entry(&mgr->tx_msg_downq, struct drm_dp_sideband_msg_tx, next);
	ret = process_single_tx_qlock(mgr, txmsg, false);
	if (ret == 1) {
		/* txmsg is sent it should be in the slots now */
		list_del(&txmsg->next);
	} else if (ret) {
		DRM_DEBUG_KMS("failed to send msg in q %d\n", ret);
		list_del(&txmsg->next);
		if (txmsg->seqno != -1)
			txmsg->dst->tx_slots[txmsg->seqno] = NULL;
		txmsg->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
//       wake_up(&mgr->tx_waitq);
	}
	if (list_empty(&mgr->tx_msg_downq)) {
		mgr->tx_down_in_progress = false;
		return;
	}
}
 
/* called holding qlock */
static void process_single_up_tx_qlock(struct drm_dp_mst_topology_mgr *mgr,
				       struct drm_dp_sideband_msg_tx *txmsg)
{
	int ret;
 
	/* construct a chunk from the first msg in the tx_msg queue */
	ret = process_single_tx_qlock(mgr, txmsg, true);
 
	if (ret != 1)
		DRM_DEBUG_KMS("failed to send msg in q %d\n", ret);
 
	txmsg->dst->tx_slots[txmsg->seqno] = NULL;
}
 
static void drm_dp_queue_down_tx(struct drm_dp_mst_topology_mgr *mgr,
				 struct drm_dp_sideband_msg_tx *txmsg)
{
	mutex_lock(&mgr->qlock);
	list_add_tail(&txmsg->next, &mgr->tx_msg_downq);
	if (!mgr->tx_down_in_progress)
		process_single_down_tx_qlock(mgr);
	mutex_unlock(&mgr->qlock);
}
 
static void drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
				     struct drm_dp_mst_branch *mstb)
{
	int len;
	struct drm_dp_sideband_msg_tx *txmsg;
	int ret;
 
	txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
	if (!txmsg)
		return;
 
	txmsg->dst = mstb;
	len = build_link_address(txmsg);
 
	mstb->link_address_sent = true;
	drm_dp_queue_down_tx(mgr, txmsg);
 
	ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
	if (ret > 0) {
		int i;
 
		if (txmsg->reply.reply_type == 1)
			DRM_DEBUG_KMS("link address nak received\n");
		else {
			DRM_DEBUG_KMS("link address reply: %d\n", txmsg->reply.u.link_addr.nports);
			for (i = 0; i < txmsg->reply.u.link_addr.nports; i++) {
				DRM_DEBUG_KMS("port %d: input %d, pdt: %d, pn: %d, dpcd_rev: %02x, mcs: %d, ddps: %d, ldps %d, sdp %d/%d\n", i,
				       txmsg->reply.u.link_addr.ports[i].input_port,
				       txmsg->reply.u.link_addr.ports[i].peer_device_type,
				       txmsg->reply.u.link_addr.ports[i].port_number,
				       txmsg->reply.u.link_addr.ports[i].dpcd_revision,
				       txmsg->reply.u.link_addr.ports[i].mcs,
				       txmsg->reply.u.link_addr.ports[i].ddps,
				       txmsg->reply.u.link_addr.ports[i].legacy_device_plug_status,
				       txmsg->reply.u.link_addr.ports[i].num_sdp_streams,
				       txmsg->reply.u.link_addr.ports[i].num_sdp_stream_sinks);
			}
 
			drm_dp_check_mstb_guid(mstb, txmsg->reply.u.link_addr.guid);
 
			for (i = 0; i < txmsg->reply.u.link_addr.nports; i++) {
				drm_dp_add_port(mstb, mgr->dev, &txmsg->reply.u.link_addr.ports[i]);
			}
			(*mgr->cbs->hotplug)(mgr);
		}
	} else {
		mstb->link_address_sent = false;
		DRM_DEBUG_KMS("link address failed %d\n", ret);
	}
 
	kfree(txmsg);
}
 
static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr,
					   struct drm_dp_mst_branch *mstb,
					   struct drm_dp_mst_port *port)
{
	int len;
	struct drm_dp_sideband_msg_tx *txmsg;
	int ret;
 
	txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
	if (!txmsg)
		return -ENOMEM;
 
	txmsg->dst = mstb;
	len = build_enum_path_resources(txmsg, port->port_num);
 
	drm_dp_queue_down_tx(mgr, txmsg);
 
	ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
	if (ret > 0) {
		if (txmsg->reply.reply_type == 1)
			DRM_DEBUG_KMS("enum path resources nak received\n");
		else {
			if (port->port_num != txmsg->reply.u.path_resources.port_number)
				DRM_ERROR("got incorrect port in response\n");
			DRM_DEBUG_KMS("enum path resources %d: %d %d\n", txmsg->reply.u.path_resources.port_number, txmsg->reply.u.path_resources.full_payload_bw_number,
			       txmsg->reply.u.path_resources.avail_payload_bw_number);
			port->available_pbn = txmsg->reply.u.path_resources.avail_payload_bw_number;
		}
	}
 
	kfree(txmsg);
	return 0;
}
 
static struct drm_dp_mst_port *drm_dp_get_last_connected_port_to_mstb(struct drm_dp_mst_branch *mstb)
{
	if (!mstb->port_parent)
		return NULL;
 
	if (mstb->port_parent->mstb != mstb)
		return mstb->port_parent;
 
	return drm_dp_get_last_connected_port_to_mstb(mstb->port_parent->parent);
}
 
static struct drm_dp_mst_branch *drm_dp_get_last_connected_port_and_mstb(struct drm_dp_mst_topology_mgr *mgr,
									 struct drm_dp_mst_branch *mstb,
									 int *port_num)
{
	struct drm_dp_mst_branch *rmstb = NULL;
	struct drm_dp_mst_port *found_port;
	mutex_lock(&mgr->lock);
	if (mgr->mst_primary) {
		found_port = drm_dp_get_last_connected_port_to_mstb(mstb);
 
		if (found_port) {
			rmstb = found_port->parent;
			kref_get(&rmstb->kref);
			*port_num = found_port->port_num;
		}
	}
	mutex_unlock(&mgr->lock);
	return rmstb;
}
 
static int drm_dp_payload_send_msg(struct drm_dp_mst_topology_mgr *mgr,
				   struct drm_dp_mst_port *port,
				   int id,
				   int pbn)
{
	struct drm_dp_sideband_msg_tx *txmsg;
	struct drm_dp_mst_branch *mstb;
	int len, ret, port_num;
 
	port = drm_dp_get_validated_port_ref(mgr, port);
	if (!port)
		return -EINVAL;
 
	port_num = port->port_num;
	mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
	if (!mstb) {
		mstb = drm_dp_get_last_connected_port_and_mstb(mgr, port->parent, &port_num);
 
		if (!mstb) {
			drm_dp_put_port(port);
		return -EINVAL;
	}
	}
 
	txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
	if (!txmsg) {
		ret = -ENOMEM;
		goto fail_put;
	}
 
	txmsg->dst = mstb;
	len = build_allocate_payload(txmsg, port_num,
				     id,
				     pbn);
 
	drm_dp_queue_down_tx(mgr, txmsg);
 
	ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
	if (ret > 0) {
		if (txmsg->reply.reply_type == 1) {
			ret = -EINVAL;
		} else
			ret = 0;
	}
	kfree(txmsg);
fail_put:
	drm_dp_put_mst_branch_device(mstb);
	drm_dp_put_port(port);
	return ret;
}
 
static int drm_dp_create_payload_step1(struct drm_dp_mst_topology_mgr *mgr,
				       int id,
				       struct drm_dp_payload *payload)
{
	int ret;
 
	ret = drm_dp_dpcd_write_payload(mgr, id, payload);
	if (ret < 0) {
		payload->payload_state = 0;
		return ret;
	}
	payload->payload_state = DP_PAYLOAD_LOCAL;
	return 0;
}
 
static int drm_dp_create_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
				       struct drm_dp_mst_port *port,
				       int id,
				       struct drm_dp_payload *payload)
{
	int ret;
	ret = drm_dp_payload_send_msg(mgr, port, id, port->vcpi.pbn);
	if (ret < 0)
		return ret;
	payload->payload_state = DP_PAYLOAD_REMOTE;
	return ret;
}
 
static int drm_dp_destroy_payload_step1(struct drm_dp_mst_topology_mgr *mgr,
					struct drm_dp_mst_port *port,
					int id,
					struct drm_dp_payload *payload)
{
	DRM_DEBUG_KMS("\n");
	/* its okay for these to fail */
	if (port) {
		drm_dp_payload_send_msg(mgr, port, id, 0);
	}
 
	drm_dp_dpcd_write_payload(mgr, id, payload);
	payload->payload_state = DP_PAYLOAD_DELETE_LOCAL;
	return 0;
}
 
static int drm_dp_destroy_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
					int id,
					struct drm_dp_payload *payload)
{
	payload->payload_state = 0;
	return 0;
}
 
/**
 * drm_dp_update_payload_part1() - Execute payload update part 1
 * @mgr: manager to use.
 *
 * This iterates over all proposed virtual channels, and tries to
 * allocate space in the link for them. For 0->slots transitions,
 * this step just writes the VCPI to the MST device. For slots->0
 * transitions, this writes the updated VCPIs and removes the
 * remote VC payloads.
 *
 * after calling this the driver should generate ACT and payload
 * packets.
 */
int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr)
{
	int i, j;
	int cur_slots = 1;
	struct drm_dp_payload req_payload;
	struct drm_dp_mst_port *port;
 
	mutex_lock(&mgr->payload_lock);
	for (i = 0; i < mgr->max_payloads; i++) {
		/* solve the current payloads - compare to the hw ones
		   - update the hw view */
		req_payload.start_slot = cur_slots;
		if (mgr->proposed_vcpis[i]) {
			port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
			port = drm_dp_get_validated_port_ref(mgr, port);
			if (!port) {
				mutex_unlock(&mgr->payload_lock);
				return -EINVAL;
			}
			req_payload.num_slots = mgr->proposed_vcpis[i]->num_slots;
		} else {
			port = NULL;
			req_payload.num_slots = 0;
		}
 
		if (mgr->payloads[i].start_slot != req_payload.start_slot) {
			mgr->payloads[i].start_slot = req_payload.start_slot;
		}
		/* work out what is required to happen with this payload */
		if (mgr->payloads[i].num_slots != req_payload.num_slots) {
 
			/* need to push an update for this payload */
			if (req_payload.num_slots) {
				drm_dp_create_payload_step1(mgr, mgr->proposed_vcpis[i]->vcpi, &req_payload);
				mgr->payloads[i].num_slots = req_payload.num_slots;
			} else if (mgr->payloads[i].num_slots) {
				mgr->payloads[i].num_slots = 0;
				drm_dp_destroy_payload_step1(mgr, port, port->vcpi.vcpi, &mgr->payloads[i]);
				req_payload.payload_state = mgr->payloads[i].payload_state;
				mgr->payloads[i].start_slot = 0;
			}
			mgr->payloads[i].payload_state = req_payload.payload_state;
		}
		cur_slots += req_payload.num_slots;
 
		if (port)
			drm_dp_put_port(port);
	}
 
	for (i = 0; i < mgr->max_payloads; i++) {
		if (mgr->payloads[i].payload_state == DP_PAYLOAD_DELETE_LOCAL) {
			DRM_DEBUG_KMS("removing payload %d\n", i);
			for (j = i; j < mgr->max_payloads - 1; j++) {
				memcpy(&mgr->payloads[j], &mgr->payloads[j + 1], sizeof(struct drm_dp_payload));
				mgr->proposed_vcpis[j] = mgr->proposed_vcpis[j + 1];
				if (mgr->proposed_vcpis[j] && mgr->proposed_vcpis[j]->num_slots) {
					set_bit(j + 1, &mgr->payload_mask);
				} else {
					clear_bit(j + 1, &mgr->payload_mask);
				}
			}
			memset(&mgr->payloads[mgr->max_payloads - 1], 0, sizeof(struct drm_dp_payload));
			mgr->proposed_vcpis[mgr->max_payloads - 1] = NULL;
			clear_bit(mgr->max_payloads, &mgr->payload_mask);
 
		}
	}
	mutex_unlock(&mgr->payload_lock);
 
	return 0;
}
EXPORT_SYMBOL(drm_dp_update_payload_part1);
 
/**
 * drm_dp_update_payload_part2() - Execute payload update part 2
 * @mgr: manager to use.
 *
 * This iterates over all proposed virtual channels, and tries to
 * allocate space in the link for them. For 0->slots transitions,
 * this step writes the remote VC payload commands. For slots->0
 * this just resets some internal state.
 */
int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr)
{
	struct drm_dp_mst_port *port;
	int i;
	int ret = 0;
	mutex_lock(&mgr->payload_lock);
	for (i = 0; i < mgr->max_payloads; i++) {
 
		if (!mgr->proposed_vcpis[i])
			continue;
 
		port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
 
		DRM_DEBUG_KMS("payload %d %d\n", i, mgr->payloads[i].payload_state);
		if (mgr->payloads[i].payload_state == DP_PAYLOAD_LOCAL) {
			ret = drm_dp_create_payload_step2(mgr, port, mgr->proposed_vcpis[i]->vcpi, &mgr->payloads[i]);
		} else if (mgr->payloads[i].payload_state == DP_PAYLOAD_DELETE_LOCAL) {
			ret = drm_dp_destroy_payload_step2(mgr, mgr->proposed_vcpis[i]->vcpi, &mgr->payloads[i]);
		}
		if (ret) {
			mutex_unlock(&mgr->payload_lock);
			return ret;
		}
	}
	mutex_unlock(&mgr->payload_lock);
	return 0;
}
EXPORT_SYMBOL(drm_dp_update_payload_part2);
 
#if 0 /* unused as of yet */
static int drm_dp_send_dpcd_read(struct drm_dp_mst_topology_mgr *mgr,
				 struct drm_dp_mst_port *port,
				 int offset, int size)
{
	int len;
	struct drm_dp_sideband_msg_tx *txmsg;
 
	txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
	if (!txmsg)
		return -ENOMEM;
 
	len = build_dpcd_read(txmsg, port->port_num, 0, 8);
	txmsg->dst = port->parent;
 
	drm_dp_queue_down_tx(mgr, txmsg);
 
	return 0;
}
#endif
 
static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr,
				  struct drm_dp_mst_port *port,
				  int offset, int size, u8 *bytes)
{
	int len;
	int ret;
	struct drm_dp_sideband_msg_tx *txmsg;
	struct drm_dp_mst_branch *mstb;
 
	mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
	if (!mstb)
		return -EINVAL;
 
	txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
	if (!txmsg) {
		ret = -ENOMEM;
		goto fail_put;
	}
 
	len = build_dpcd_write(txmsg, port->port_num, offset, size, bytes);
	txmsg->dst = mstb;
 
	drm_dp_queue_down_tx(mgr, txmsg);
 
	ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
	if (ret > 0) {
		if (txmsg->reply.reply_type == 1) {
			ret = -EINVAL;
		} else
			ret = 0;
	}
	kfree(txmsg);
fail_put:
	drm_dp_put_mst_branch_device(mstb);
	return ret;
}
 
static int drm_dp_encode_up_ack_reply(struct drm_dp_sideband_msg_tx *msg, u8 req_type)
{
	struct drm_dp_sideband_msg_reply_body reply;
 
	reply.reply_type = 1;
	reply.req_type = req_type;
	drm_dp_encode_sideband_reply(&reply, msg);
	return 0;
}
 
static int drm_dp_send_up_ack_reply(struct drm_dp_mst_topology_mgr *mgr,
				    struct drm_dp_mst_branch *mstb,
				    int req_type, int seqno, bool broadcast)
{
	struct drm_dp_sideband_msg_tx *txmsg;
 
	txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
	if (!txmsg)
		return -ENOMEM;
 
	txmsg->dst = mstb;
	txmsg->seqno = seqno;
	drm_dp_encode_up_ack_reply(txmsg, req_type);
 
	mutex_lock(&mgr->qlock);
 
	process_single_up_tx_qlock(mgr, txmsg);
 
	mutex_unlock(&mgr->qlock);
 
	kfree(txmsg);
	return 0;
}
 
static bool drm_dp_get_vc_payload_bw(int dp_link_bw,
				     int dp_link_count,
				     int *out)
{
	switch (dp_link_bw) {
	default:
		DRM_DEBUG_KMS("invalid link bandwidth in DPCD: %x (link count: %d)\n",
			      dp_link_bw, dp_link_count);
		return false;
 
	case DP_LINK_BW_1_62:
		*out = 3 * dp_link_count;
		break;
	case DP_LINK_BW_2_7:
		*out = 5 * dp_link_count;
		break;
	case DP_LINK_BW_5_4:
		*out = 10 * dp_link_count;
		break;
	}
	return true;
}
 
/**
 * drm_dp_mst_topology_mgr_set_mst() - Set the MST state for a topology manager
 * @mgr: manager to set state for
 * @mst_state: true to enable MST on this connector - false to disable.
 *
 * This is called by the driver when it detects an MST capable device plugged
 * into a DP MST capable port, or when a DP MST capable device is unplugged.
 */
int drm_dp_mst_topology_mgr_set_mst(struct drm_dp_mst_topology_mgr *mgr, bool mst_state)
{
	int ret = 0;
	struct drm_dp_mst_branch *mstb = NULL;
 
	mutex_lock(&mgr->lock);
	if (mst_state == mgr->mst_state)
		goto out_unlock;
 
	mgr->mst_state = mst_state;
	/* set the device into MST mode */
	if (mst_state) {
		WARN_ON(mgr->mst_primary);
 
		/* get dpcd info */
		ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE);
		if (ret != DP_RECEIVER_CAP_SIZE) {
			DRM_DEBUG_KMS("failed to read DPCD\n");
			goto out_unlock;
		}
 
		if (!drm_dp_get_vc_payload_bw(mgr->dpcd[1],
					      mgr->dpcd[2] & DP_MAX_LANE_COUNT_MASK,
					      &mgr->pbn_div)) {
			ret = -EINVAL;
			goto out_unlock;
		}
 
		mgr->total_pbn = 2560;
		mgr->total_slots = DIV_ROUND_UP(mgr->total_pbn, mgr->pbn_div);
		mgr->avail_slots = mgr->total_slots;
 
		/* add initial branch device at LCT 1 */
		mstb = drm_dp_add_mst_branch_device(1, NULL);
		if (mstb == NULL) {
			ret = -ENOMEM;
			goto out_unlock;
		}
		mstb->mgr = mgr;
 
		/* give this the main reference */
		mgr->mst_primary = mstb;
		kref_get(&mgr->mst_primary->kref);
 
		ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
					 DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC);
		if (ret < 0) {
			goto out_unlock;
		}
 
		{
			struct drm_dp_payload reset_pay;
			reset_pay.start_slot = 0;
			reset_pay.num_slots = 0x3f;
			drm_dp_dpcd_write_payload(mgr, 0, &reset_pay);
		}
 
//       queue_work(system_long_wq, &mgr->work);
 
		ret = 0;
	} else {
		/* disable MST on the device */
		mstb = mgr->mst_primary;
		mgr->mst_primary = NULL;
		/* this can fail if the device is gone */
		drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, 0);
		ret = 0;
		memset(mgr->payloads, 0, mgr->max_payloads * sizeof(struct drm_dp_payload));
		mgr->payload_mask = 0;
		set_bit(0, &mgr->payload_mask);
		mgr->vcpi_mask = 0;
	}
 
out_unlock:
	mutex_unlock(&mgr->lock);
	if (mstb)
		drm_dp_put_mst_branch_device(mstb);
	return ret;
 
}
EXPORT_SYMBOL(drm_dp_mst_topology_mgr_set_mst);
 
/**
 * drm_dp_mst_topology_mgr_suspend() - suspend the MST manager
 * @mgr: manager to suspend
 *
 * This function tells the MST device that we can't handle UP messages
 * anymore. This should stop it from sending any since we are suspended.
 */
void drm_dp_mst_topology_mgr_suspend(struct drm_dp_mst_topology_mgr *mgr)
{
	mutex_lock(&mgr->lock);
	drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
			   DP_MST_EN | DP_UPSTREAM_IS_SRC);
	mutex_unlock(&mgr->lock);
}
EXPORT_SYMBOL(drm_dp_mst_topology_mgr_suspend);
 
/**
 * drm_dp_mst_topology_mgr_resume() - resume the MST manager
 * @mgr: manager to resume
 *
 * This will fetch DPCD and see if the device is still there,
 * if it is, it will rewrite the MSTM control bits, and return.
 *
 * if the device fails this returns -1, and the driver should do
 * a full MST reprobe, in case we were undocked.
 */
int drm_dp_mst_topology_mgr_resume(struct drm_dp_mst_topology_mgr *mgr)
{
	int ret = 0;
 
	mutex_lock(&mgr->lock);
 
	if (mgr->mst_primary) {
		int sret;
		u8 guid[16];
 
		sret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE);
		if (sret != DP_RECEIVER_CAP_SIZE) {
			DRM_DEBUG_KMS("dpcd read failed - undocked during suspend?\n");
			ret = -1;
			goto out_unlock;
		}
 
		ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
					 DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC);
		if (ret < 0) {
			DRM_DEBUG_KMS("mst write failed - undocked during suspend?\n");
			ret = -1;
			goto out_unlock;
		}
 
		/* Some hubs forget their guids after they resume */
		sret = drm_dp_dpcd_read(mgr->aux, DP_GUID, guid, 16);
		if (sret != 16) {
			DRM_DEBUG_KMS("dpcd read failed - undocked during suspend?\n");
			ret = -1;
			goto out_unlock;
		}
		drm_dp_check_mstb_guid(mgr->mst_primary, guid);
 
		ret = 0;
	} else
		ret = -1;
 
out_unlock:
	mutex_unlock(&mgr->lock);
	return ret;
}
EXPORT_SYMBOL(drm_dp_mst_topology_mgr_resume);
 
static void drm_dp_get_one_sb_msg(struct drm_dp_mst_topology_mgr *mgr, bool up)
{
	int len;
	u8 replyblock[32];
	int replylen, origlen, curreply;
	int ret;
	struct drm_dp_sideband_msg_rx *msg;
	int basereg = up ? DP_SIDEBAND_MSG_UP_REQ_BASE : DP_SIDEBAND_MSG_DOWN_REP_BASE;
	msg = up ? &mgr->up_req_recv : &mgr->down_rep_recv;
 
	len = min(mgr->max_dpcd_transaction_bytes, 16);
	ret = drm_dp_dpcd_read(mgr->aux, basereg,
			       replyblock, len);
	if (ret != len) {
		DRM_DEBUG_KMS("failed to read DPCD down rep %d %d\n", len, ret);
		return;
	}
	ret = drm_dp_sideband_msg_build(msg, replyblock, len, true);
	if (!ret) {
		DRM_DEBUG_KMS("sideband msg build failed %d\n", replyblock[0]);
		return;
	}
	replylen = msg->curchunk_len + msg->curchunk_hdrlen;
 
	origlen = replylen;
	replylen -= len;
	curreply = len;
	while (replylen > 0) {
		len = min3(replylen, mgr->max_dpcd_transaction_bytes, 16);
		ret = drm_dp_dpcd_read(mgr->aux, basereg + curreply,
				    replyblock, len);
		if (ret != len) {
			DRM_DEBUG_KMS("failed to read a chunk\n");
		}
		ret = drm_dp_sideband_msg_build(msg, replyblock, len, false);
		if (ret == false)
			DRM_DEBUG_KMS("failed to build sideband msg\n");
		curreply += len;
		replylen -= len;
	}
}
 
static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr *mgr)
{
	int ret = 0;
 
	drm_dp_get_one_sb_msg(mgr, false);
 
	if (mgr->down_rep_recv.have_eomt) {
		struct drm_dp_sideband_msg_tx *txmsg;
		struct drm_dp_mst_branch *mstb;
		int slot = -1;
		mstb = drm_dp_get_mst_branch_device(mgr,
						    mgr->down_rep_recv.initial_hdr.lct,
						    mgr->down_rep_recv.initial_hdr.rad);
 
		if (!mstb) {
			DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->down_rep_recv.initial_hdr.lct);
			memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
			return 0;
		}
 
		/* find the message */
		slot = mgr->down_rep_recv.initial_hdr.seqno;
		mutex_lock(&mgr->qlock);
		txmsg = mstb->tx_slots[slot];
		/* remove from slots */
		mutex_unlock(&mgr->qlock);
 
		if (!txmsg) {
			DRM_DEBUG_KMS("Got MST reply with no msg %p %d %d %02x %02x\n",
			       mstb,
			       mgr->down_rep_recv.initial_hdr.seqno,
			       mgr->down_rep_recv.initial_hdr.lct,
				      mgr->down_rep_recv.initial_hdr.rad[0],
				      mgr->down_rep_recv.msg[0]);
			drm_dp_put_mst_branch_device(mstb);
			memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
			return 0;
		}
 
		drm_dp_sideband_parse_reply(&mgr->down_rep_recv, &txmsg->reply);
		if (txmsg->reply.reply_type == 1) {
			DRM_DEBUG_KMS("Got NAK reply: req 0x%02x, reason 0x%02x, nak data 0x%02x\n", txmsg->reply.req_type, txmsg->reply.u.nak.reason, txmsg->reply.u.nak.nak_data);
		}
 
		memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
		drm_dp_put_mst_branch_device(mstb);
 
		mutex_lock(&mgr->qlock);
		txmsg->state = DRM_DP_SIDEBAND_TX_RX;
		mstb->tx_slots[slot] = NULL;
		mutex_unlock(&mgr->qlock);
 
//       wake_up(&mgr->tx_waitq);
	}
	return ret;
}
 
static int drm_dp_mst_handle_up_req(struct drm_dp_mst_topology_mgr *mgr)
{
	int ret = 0;
	drm_dp_get_one_sb_msg(mgr, true);
 
	if (mgr->up_req_recv.have_eomt) {
		struct drm_dp_sideband_msg_req_body msg;
		struct drm_dp_mst_branch *mstb = NULL;
		bool seqno;
 
		if (!mgr->up_req_recv.initial_hdr.broadcast) {
		mstb = drm_dp_get_mst_branch_device(mgr,
						    mgr->up_req_recv.initial_hdr.lct,
						    mgr->up_req_recv.initial_hdr.rad);
		if (!mstb) {
			DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->up_req_recv.initial_hdr.lct);
			memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
			return 0;
		}
		}
 
		seqno = mgr->up_req_recv.initial_hdr.seqno;
		drm_dp_sideband_parse_req(&mgr->up_req_recv, &msg);
 
		if (msg.req_type == DP_CONNECTION_STATUS_NOTIFY) {
			drm_dp_send_up_ack_reply(mgr, mgr->mst_primary, msg.req_type, seqno, false);
 
			if (!mstb)
				mstb = drm_dp_get_mst_branch_device_by_guid(mgr, msg.u.conn_stat.guid);
 
			if (!mstb) {
				DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->up_req_recv.initial_hdr.lct);
				memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
				return 0;
			}
 
			drm_dp_update_port(mstb, &msg.u.conn_stat);
 
			DRM_DEBUG_KMS("Got CSN: pn: %d ldps:%d ddps: %d mcs: %d ip: %d pdt: %d\n", msg.u.conn_stat.port_number, msg.u.conn_stat.legacy_device_plug_status, msg.u.conn_stat.displayport_device_plug_status, msg.u.conn_stat.message_capability_status, msg.u.conn_stat.input_port, msg.u.conn_stat.peer_device_type);
			(*mgr->cbs->hotplug)(mgr);
 
		} else if (msg.req_type == DP_RESOURCE_STATUS_NOTIFY) {
			drm_dp_send_up_ack_reply(mgr, mgr->mst_primary, msg.req_type, seqno, false);
			if (!mstb)
				mstb = drm_dp_get_mst_branch_device_by_guid(mgr, msg.u.resource_stat.guid);
 
			if (!mstb) {
				DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->up_req_recv.initial_hdr.lct);
				memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
				return 0;
			}
 
			DRM_DEBUG_KMS("Got RSN: pn: %d avail_pbn %d\n", msg.u.resource_stat.port_number, msg.u.resource_stat.available_pbn);
		}
 
		drm_dp_put_mst_branch_device(mstb);
		memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
	}
	return ret;
}
 
/**
 * drm_dp_mst_hpd_irq() - MST hotplug IRQ notify
 * @mgr: manager to notify irq for.
 * @esi: 4 bytes from SINK_COUNT_ESI
 * @handled: whether the hpd interrupt was consumed or not
 *
 * This should be called from the driver when it detects a short IRQ,
 * along with the value of the DEVICE_SERVICE_IRQ_VECTOR_ESI0. The
 * topology manager will process the sideband messages received as a result
 * of this.
 */
int drm_dp_mst_hpd_irq(struct drm_dp_mst_topology_mgr *mgr, u8 *esi, bool *handled)
{
	int ret = 0;
	int sc;
	*handled = false;
	sc = esi[0] & 0x3f;
 
	if (sc != mgr->sink_count) {
		mgr->sink_count = sc;
		*handled = true;
	}
 
	if (esi[1] & DP_DOWN_REP_MSG_RDY) {
		ret = drm_dp_mst_handle_down_rep(mgr);
		*handled = true;
	}
 
	if (esi[1] & DP_UP_REQ_MSG_RDY) {
		ret |= drm_dp_mst_handle_up_req(mgr);
		*handled = true;
	}
 
	drm_dp_mst_kick_tx(mgr);
	return ret;
}
EXPORT_SYMBOL(drm_dp_mst_hpd_irq);
 
/**
 * drm_dp_mst_detect_port() - get connection status for an MST port
 * @mgr: manager for this port
 * @port: unverified pointer to a port
 *
 * This returns the current connection state for a port. It validates the
 * port pointer still exists so the caller doesn't require a reference
 */
enum drm_connector_status drm_dp_mst_detect_port(struct drm_connector *connector,
						 struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
{
	enum drm_connector_status status = connector_status_disconnected;
 
	/* we need to search for the port in the mgr in case its gone */
	port = drm_dp_get_validated_port_ref(mgr, port);
	if (!port)
		return connector_status_disconnected;
 
	if (!port->ddps)
		goto out;
 
	switch (port->pdt) {
	case DP_PEER_DEVICE_NONE:
	case DP_PEER_DEVICE_MST_BRANCHING:
		break;
 
	case DP_PEER_DEVICE_SST_SINK:
		status = connector_status_connected;
		/* for logical ports - cache the EDID */
		if (port->port_num >= 8 && !port->cached_edid) {
			port->cached_edid = drm_get_edid(connector, &port->aux.ddc);
		}
		break;
	case DP_PEER_DEVICE_DP_LEGACY_CONV:
		if (port->ldps)
			status = connector_status_connected;
		break;
	}
out:
	drm_dp_put_port(port);
	return status;
}
EXPORT_SYMBOL(drm_dp_mst_detect_port);
 
/**
 * drm_dp_mst_get_edid() - get EDID for an MST port
 * @connector: toplevel connector to get EDID for
 * @mgr: manager for this port
 * @port: unverified pointer to a port.
 *
 * This returns an EDID for the port connected to a connector,
 * It validates the pointer still exists so the caller doesn't require a
 * reference.
 */
struct edid *drm_dp_mst_get_edid(struct drm_connector *connector, struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
{
	struct edid *edid = NULL;
 
	/* we need to search for the port in the mgr in case its gone */
	port = drm_dp_get_validated_port_ref(mgr, port);
	if (!port)
		return NULL;
 
	if (port->cached_edid)
		edid = drm_edid_duplicate(port->cached_edid);
	else {
		edid = drm_get_edid(connector, &port->aux.ddc);
		drm_mode_connector_set_tile_property(connector);
	}
	drm_dp_put_port(port);
	return edid;
}
EXPORT_SYMBOL(drm_dp_mst_get_edid);
 
/**
 * drm_dp_find_vcpi_slots() - find slots for this PBN value
 * @mgr: manager to use
 * @pbn: payload bandwidth to convert into slots.
 */
int drm_dp_find_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr,
			   int pbn)
{
	int num_slots;
 
	num_slots = DIV_ROUND_UP(pbn, mgr->pbn_div);
 
	if (num_slots > mgr->avail_slots)
		return -ENOSPC;
	return num_slots;
}
EXPORT_SYMBOL(drm_dp_find_vcpi_slots);
 
static int drm_dp_init_vcpi(struct drm_dp_mst_topology_mgr *mgr,
			    struct drm_dp_vcpi *vcpi, int pbn)
{
	int num_slots;
	int ret;
 
	num_slots = DIV_ROUND_UP(pbn, mgr->pbn_div);
 
	if (num_slots > mgr->avail_slots)
		return -ENOSPC;
 
	vcpi->pbn = pbn;
	vcpi->aligned_pbn = num_slots * mgr->pbn_div;
	vcpi->num_slots = num_slots;
 
	ret = drm_dp_mst_assign_payload_id(mgr, vcpi);
	if (ret < 0)
		return ret;
	return 0;
}
 
/**
 * drm_dp_mst_allocate_vcpi() - Allocate a virtual channel
 * @mgr: manager for this port
 * @port: port to allocate a virtual channel for.
 * @pbn: payload bandwidth number to request
 * @slots: returned number of slots for this PBN.
 */
bool drm_dp_mst_allocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, int pbn, int *slots)
{
	int ret;
 
	port = drm_dp_get_validated_port_ref(mgr, port);
	if (!port)
		return false;
 
	if (port->vcpi.vcpi > 0) {
		DRM_DEBUG_KMS("payload: vcpi %d already allocated for pbn %d - requested pbn %d\n", port->vcpi.vcpi, port->vcpi.pbn, pbn);
		if (pbn == port->vcpi.pbn) {
			*slots = port->vcpi.num_slots;
			drm_dp_put_port(port);
			return true;
		}
	}
 
	ret = drm_dp_init_vcpi(mgr, &port->vcpi, pbn);
	if (ret) {
		DRM_DEBUG_KMS("failed to init vcpi %d %d %d\n", DIV_ROUND_UP(pbn, mgr->pbn_div), mgr->avail_slots, ret);
		goto out;
	}
	DRM_DEBUG_KMS("initing vcpi for %d %d\n", pbn, port->vcpi.num_slots);
	*slots = port->vcpi.num_slots;
 
	drm_dp_put_port(port);
	return true;
out:
	return false;
}
EXPORT_SYMBOL(drm_dp_mst_allocate_vcpi);
 
int drm_dp_mst_get_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
{
	int slots = 0;
	port = drm_dp_get_validated_port_ref(mgr, port);
	if (!port)
		return slots;
 
	slots = port->vcpi.num_slots;
	drm_dp_put_port(port);
	return slots;
}
EXPORT_SYMBOL(drm_dp_mst_get_vcpi_slots);
 
/**
 * drm_dp_mst_reset_vcpi_slots() - Reset number of slots to 0 for VCPI
 * @mgr: manager for this port
 * @port: unverified pointer to a port.
 *
 * This just resets the number of slots for the ports VCPI for later programming.
 */
void drm_dp_mst_reset_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
{
	port = drm_dp_get_validated_port_ref(mgr, port);
	if (!port)
		return;
	port->vcpi.num_slots = 0;
	drm_dp_put_port(port);
}
EXPORT_SYMBOL(drm_dp_mst_reset_vcpi_slots);
 
/**
 * drm_dp_mst_deallocate_vcpi() - deallocate a VCPI
 * @mgr: manager for this port
 * @port: unverified port to deallocate vcpi for
 */
void drm_dp_mst_deallocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
{
	port = drm_dp_get_validated_port_ref(mgr, port);
	if (!port)
		return;
 
	drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi);
	port->vcpi.num_slots = 0;
	port->vcpi.pbn = 0;
	port->vcpi.aligned_pbn = 0;
	port->vcpi.vcpi = 0;
	drm_dp_put_port(port);
}
EXPORT_SYMBOL(drm_dp_mst_deallocate_vcpi);
 
static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr,
				     int id, struct drm_dp_payload *payload)
{
	u8 payload_alloc[3], status;
	int ret;
	int retries = 0;
 
	drm_dp_dpcd_writeb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS,
			   DP_PAYLOAD_TABLE_UPDATED);
 
	payload_alloc[0] = id;
	payload_alloc[1] = payload->start_slot;
	payload_alloc[2] = payload->num_slots;
 
	ret = drm_dp_dpcd_write(mgr->aux, DP_PAYLOAD_ALLOCATE_SET, payload_alloc, 3);
	if (ret != 3) {
		DRM_DEBUG_KMS("failed to write payload allocation %d\n", ret);
		goto fail;
	}
 
retry:
	ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status);
	if (ret < 0) {
		DRM_DEBUG_KMS("failed to read payload table status %d\n", ret);
		goto fail;
	}
 
	if (!(status & DP_PAYLOAD_TABLE_UPDATED)) {
		retries++;
		if (retries < 20) {
			usleep_range(10000, 20000);
			goto retry;
		}
		DRM_DEBUG_KMS("status not set after read payload table status %d\n", status);
		ret = -EINVAL;
		goto fail;
	}
	ret = 0;
fail:
	return ret;
}
 
 
/**
 * drm_dp_check_act_status() - Check ACT handled status.
 * @mgr: manager to use
 *
 * Check the payload status bits in the DPCD for ACT handled completion.
 */
int drm_dp_check_act_status(struct drm_dp_mst_topology_mgr *mgr)
{
	u8 status;
	int ret;
	int count = 0;
 
	do {
		ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status);
 
		if (ret < 0) {
			DRM_DEBUG_KMS("failed to read payload table status %d\n", ret);
			goto fail;
		}
 
		if (status & DP_PAYLOAD_ACT_HANDLED)
			break;
		count++;
		udelay(100);
 
	} while (count < 30);
 
	if (!(status & DP_PAYLOAD_ACT_HANDLED)) {
		DRM_DEBUG_KMS("failed to get ACT bit %d after %d retries\n", status, count);
		ret = -EINVAL;
		goto fail;
	}
	return 0;
fail:
	return ret;
}
EXPORT_SYMBOL(drm_dp_check_act_status);
 
/**
 * drm_dp_calc_pbn_mode() - Calculate the PBN for a mode.
 * @clock: dot clock for the mode
 * @bpp: bpp for the mode.
 *
 * This uses the formula in the spec to calculate the PBN value for a mode.
 */
int drm_dp_calc_pbn_mode(int clock, int bpp)
{
	u64 kbps;
	s64 peak_kbps;
	u32 numerator;
	u32 denominator;
 
	kbps = clock * bpp;
 
	/*
	 * margin 5300ppm + 300ppm ~ 0.6% as per spec, factor is 1.006
	 * The unit of 54/64Mbytes/sec is an arbitrary unit chosen based on
	 * common multiplier to render an integer PBN for all link rate/lane
	 * counts combinations
	 * calculate
	 * peak_kbps *= (1006/1000)
	 * peak_kbps *= (64/54)
	 * peak_kbps *= 8    convert to bytes
	 */
 
	numerator = 64 * 1006;
	denominator = 54 * 8 * 1000 * 1000;
 
	kbps *= numerator;
	peak_kbps = drm_fixp_from_fraction(kbps, denominator);
 
	return drm_fixp2int_ceil(peak_kbps);
}
EXPORT_SYMBOL(drm_dp_calc_pbn_mode);
 
static int test_calc_pbn_mode(void)
{
	int ret;
	ret = drm_dp_calc_pbn_mode(154000, 30);
	if (ret != 689) {
		DRM_ERROR("PBN calculation test failed - clock %d, bpp %d, expected PBN %d, actual PBN %d.\n",
				154000, 30, 689, ret);
		return -EINVAL;
	}
	ret = drm_dp_calc_pbn_mode(234000, 30);
	if (ret != 1047) {
		DRM_ERROR("PBN calculation test failed - clock %d, bpp %d, expected PBN %d, actual PBN %d.\n",
				234000, 30, 1047, ret);
		return -EINVAL;
	}
	ret = drm_dp_calc_pbn_mode(297000, 24);
	if (ret != 1063) {
		DRM_ERROR("PBN calculation test failed - clock %d, bpp %d, expected PBN %d, actual PBN %d.\n",
				297000, 24, 1063, ret);
		return -EINVAL;
	}
	return 0;
}
 
/* we want to kick the TX after we've ack the up/down IRQs. */
static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr)
{
//   queue_work(system_long_wq, &mgr->tx_work);
}
 
static void drm_dp_mst_dump_mstb(struct seq_file *m,
				 struct drm_dp_mst_branch *mstb)
{
	struct drm_dp_mst_port *port;
	int tabs = mstb->lct;
	char prefix[10];
	int i;
 
	for (i = 0; i < tabs; i++)
		prefix[i] = '\t';
	prefix[i] = '\0';
 
//   seq_printf(m, "%smst: %p, %d\n", prefix, mstb, mstb->num_ports);
//   list_for_each_entry(port, &mstb->ports, next) {
//       seq_printf(m, "%sport: %d: ddps: %d ldps: %d, %p, conn: %p\n", prefix, port->port_num, port->ddps, port->ldps, port, port->connector);
//       if (port->mstb)
//           drm_dp_mst_dump_mstb(m, port->mstb);
//   }
}
 
static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr,
				  char *buf)
{
	int ret;
	int i;
	for (i = 0; i < 4; i++) {
		ret = drm_dp_dpcd_read(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS + (i * 16), &buf[i * 16], 16);
		if (ret != 16)
			break;
	}
	if (i == 4)
		return true;
	return false;
}
 
/**
 * drm_dp_mst_dump_topology(): dump topology to seq file.
 * @m: seq_file to dump output to
 * @mgr: manager to dump current topology for.
 *
 * helper to dump MST topology to a seq file for debugfs.
 */
void drm_dp_mst_dump_topology(struct seq_file *m,
			      struct drm_dp_mst_topology_mgr *mgr)
{
	int i;
	struct drm_dp_mst_port *port;
	mutex_lock(&mgr->lock);
	if (mgr->mst_primary)
		drm_dp_mst_dump_mstb(m, mgr->mst_primary);
 
	/* dump VCPIs */
	mutex_unlock(&mgr->lock);
 
 
 
}
EXPORT_SYMBOL(drm_dp_mst_dump_topology);
 
static void drm_dp_tx_work(struct work_struct *work)
{
	struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, tx_work);
 
	mutex_lock(&mgr->qlock);
	if (mgr->tx_down_in_progress)
		process_single_down_tx_qlock(mgr);
	mutex_unlock(&mgr->qlock);
}
 
static void drm_dp_free_mst_port(struct kref *kref)
{
	struct drm_dp_mst_port *port = container_of(kref, struct drm_dp_mst_port, kref);
	kref_put(&port->parent->kref, drm_dp_free_mst_branch_device);
	kfree(port);
}
/**
 * drm_dp_mst_topology_mgr_init - initialise a topology manager
 * @mgr: manager struct to initialise
 * @dev: device providing this structure - for i2c addition.
 * @aux: DP helper aux channel to talk to this device
 * @max_dpcd_transaction_bytes: hw specific DPCD transaction limit
 * @max_payloads: maximum number of payloads this GPU can source
 * @conn_base_id: the connector object ID the MST device is connected to.
 *
 * Return 0 for success, or negative error code on failure
 */
int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr,
				 struct device *dev, struct drm_dp_aux *aux,
				 int max_dpcd_transaction_bytes,
				 int max_payloads, int conn_base_id)
{
	mutex_init(&mgr->lock);
	mutex_init(&mgr->qlock);
	mutex_init(&mgr->payload_lock);
	mutex_init(&mgr->destroy_connector_lock);
	INIT_LIST_HEAD(&mgr->tx_msg_downq);
	INIT_LIST_HEAD(&mgr->destroy_connector_list);
	INIT_WORK(&mgr->work, drm_dp_mst_link_probe_work);
	INIT_WORK(&mgr->tx_work, drm_dp_tx_work);
	init_waitqueue_head(&mgr->tx_waitq);
	mgr->dev = dev;
	mgr->aux = aux;
	mgr->max_dpcd_transaction_bytes = max_dpcd_transaction_bytes;
	mgr->max_payloads = max_payloads;
	mgr->conn_base_id = conn_base_id;
	mgr->payloads = kcalloc(max_payloads, sizeof(struct drm_dp_payload), GFP_KERNEL);
	if (!mgr->payloads)
		return -ENOMEM;
	mgr->proposed_vcpis = kcalloc(max_payloads, sizeof(struct drm_dp_vcpi *), GFP_KERNEL);
	if (!mgr->proposed_vcpis)
		return -ENOMEM;
	set_bit(0, &mgr->payload_mask);
	test_calc_pbn_mode();
	return 0;
}
EXPORT_SYMBOL(drm_dp_mst_topology_mgr_init);
 
/**
 * drm_dp_mst_topology_mgr_destroy() - destroy topology manager.
 * @mgr: manager to destroy
 */
void drm_dp_mst_topology_mgr_destroy(struct drm_dp_mst_topology_mgr *mgr)
{
	mutex_lock(&mgr->payload_lock);
	kfree(mgr->payloads);
	mgr->payloads = NULL;
	kfree(mgr->proposed_vcpis);
	mgr->proposed_vcpis = NULL;
	mutex_unlock(&mgr->payload_lock);
	mgr->dev = NULL;
	mgr->aux = NULL;
}
EXPORT_SYMBOL(drm_dp_mst_topology_mgr_destroy);
 
/* I2C device */
static int drm_dp_mst_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs,
			       int num)
{
	struct drm_dp_aux *aux = adapter->algo_data;
	struct drm_dp_mst_port *port = container_of(aux, struct drm_dp_mst_port, aux);
	struct drm_dp_mst_branch *mstb;
	struct drm_dp_mst_topology_mgr *mgr = port->mgr;
	unsigned int i;
	bool reading = false;
	struct drm_dp_sideband_msg_req_body msg;
	struct drm_dp_sideband_msg_tx *txmsg = NULL;
	int ret;
 
	mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
	if (!mstb)
		return -EREMOTEIO;
 
	/* construct i2c msg */
	/* see if last msg is a read */
	if (msgs[num - 1].flags & I2C_M_RD)
		reading = true;
 
	if (!reading || (num - 1 > DP_REMOTE_I2C_READ_MAX_TRANSACTIONS)) {
		DRM_DEBUG_KMS("Unsupported I2C transaction for MST device\n");
		ret = -EIO;
		goto out;
	}
 
	memset(&msg, 0, sizeof(msg));
	msg.req_type = DP_REMOTE_I2C_READ;
	msg.u.i2c_read.num_transactions = num - 1;
	msg.u.i2c_read.port_number = port->port_num;
	for (i = 0; i < num - 1; i++) {
		msg.u.i2c_read.transactions[i].i2c_dev_id = msgs[i].addr;
		msg.u.i2c_read.transactions[i].num_bytes = msgs[i].len;
		msg.u.i2c_read.transactions[i].bytes = msgs[i].buf;
	}
	msg.u.i2c_read.read_i2c_device_id = msgs[num - 1].addr;
	msg.u.i2c_read.num_bytes_read = msgs[num - 1].len;
 
	txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
	if (!txmsg) {
		ret = -ENOMEM;
		goto out;
	}
 
	txmsg->dst = mstb;
	drm_dp_encode_sideband_req(&msg, txmsg);
 
	drm_dp_queue_down_tx(mgr, txmsg);
 
	ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
	if (ret > 0) {
 
		if (txmsg->reply.reply_type == 1) { /* got a NAK back */
			ret = -EREMOTEIO;
			goto out;
		}
		if (txmsg->reply.u.remote_i2c_read_ack.num_bytes != msgs[num - 1].len) {
			ret = -EIO;
			goto out;
		}
		memcpy(msgs[num - 1].buf, txmsg->reply.u.remote_i2c_read_ack.bytes, msgs[num - 1].len);
		ret = num;
	}
out:
	kfree(txmsg);
	drm_dp_put_mst_branch_device(mstb);
	return ret;
}
 
static u32 drm_dp_mst_i2c_functionality(struct i2c_adapter *adapter)
{
	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
	       I2C_FUNC_SMBUS_READ_BLOCK_DATA |
	       I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
	       I2C_FUNC_10BIT_ADDR;
}
 
static const struct i2c_algorithm drm_dp_mst_i2c_algo = {
	.functionality = drm_dp_mst_i2c_functionality,
	.master_xfer = drm_dp_mst_i2c_xfer,
};
 
/**
 * drm_dp_mst_register_i2c_bus() - register an I2C adapter for I2C-over-AUX
 * @aux: DisplayPort AUX channel
 *
 * Returns 0 on success or a negative error code on failure.
 */
static int drm_dp_mst_register_i2c_bus(struct drm_dp_aux *aux)
{
	aux->ddc.algo = &drm_dp_mst_i2c_algo;
	aux->ddc.algo_data = aux;
	aux->ddc.retries = 3;
 
	aux->ddc.class = I2C_CLASS_DDC;
	aux->ddc.owner = THIS_MODULE;
	aux->ddc.dev.parent = aux->dev;
 
	return i2c_add_adapter(&aux->ddc);
}
 
/**
 * drm_dp_mst_unregister_i2c_bus() - unregister an I2C-over-AUX adapter
 * @aux: DisplayPort AUX channel
 */
static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_aux *aux)
{
	i2c_del_adapter(&aux->ddc);
}

Rev 6320	Rev 6660
1	/*	1	/*
2	* Copyright © 2014 Red Hat	2	* Copyright © 2014 Red Hat
3	*	3	*
4	* Permission to use, copy, modify, distribute, and sell this software and its	4	* Permission to use, copy, modify, distribute, and sell this software and its
5	* documentation for any purpose is hereby granted without fee, provided that	5	* documentation for any purpose is hereby granted without fee, provided that
6	* the above copyright notice appear in all copies and that both that copyright	6	* the above copyright notice appear in all copies and that both that copyright
7	* notice and this permission notice appear in supporting documentation, and	7	* notice and this permission notice appear in supporting documentation, and
8	* that the name of the copyright holders not be used in advertising or	8	* that the name of the copyright holders not be used in advertising or
9	* publicity pertaining to distribution of the software without specific,	9	* publicity pertaining to distribution of the software without specific,
10	* written prior permission. The copyright holders make no representations	10	* written prior permission. The copyright holders make no representations
11	* about the suitability of this software for any purpose. It is provided "as	11	* about the suitability of this software for any purpose. It is provided "as
12	* is" without express or implied warranty.	12	* is" without express or implied warranty.
13	*	13	*
14	* THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,	14	* THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
15	* INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO	15	* INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
16	* EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR	16	* EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
17	* CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,	17	* CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
18	* DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER	18	* DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
19	* TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE	19	* TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
20	* OF THIS SOFTWARE.	20	* OF THIS SOFTWARE.
21	*/	21	*/
22		22
23	#include	23	#include
24	#include	24	#include
25	#include	25	#include
26	#include	26	#include
27	#include	27	#include
28	#include	28	#include
29	#include	29	#include
30	#include	30	#include
31	#include	31	#include
32	#include	32	#include
33	#include	33	#include
34	#include	34	#include
35	#include	35	#include
36		36
37	#include	37	#include
38		38
39	u64 get_jiffies_64(void)	39	u64 get_jiffies_64(void)
40	{	40	{
41	return jiffies;	41	return jiffies;
42	}	42	}
43	/**	43	/**
44	* DOC: dp mst helper	44	* DOC: dp mst helper
45	*	45	*
46	* These functions contain parts of the DisplayPort 1.2a MultiStream Transport	46	* These functions contain parts of the DisplayPort 1.2a MultiStream Transport
47	* protocol. The helpers contain a topology manager and bandwidth manager.	47	* protocol. The helpers contain a topology manager and bandwidth manager.
48	* The helpers encapsulate the sending and received of sideband msgs.	48	* The helpers encapsulate the sending and received of sideband msgs.
49	*/	49	*/
50	static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr,	50	static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr,
51	char *buf);	51	char *buf);
52	static int test_calc_pbn_mode(void);	52	static int test_calc_pbn_mode(void);
53		53
54	static void drm_dp_put_port(struct drm_dp_mst_port *port);	54	static void drm_dp_put_port(struct drm_dp_mst_port *port);
55		55
56	static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr,	56	static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr,
57	int id,	57	int id,
58	struct drm_dp_payload *payload);	58	struct drm_dp_payload *payload);
59		59
60	static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr,	60	static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr,
61	struct drm_dp_mst_port *port,	61	struct drm_dp_mst_port *port,
62	int offset, int size, u8 *bytes);	62	int offset, int size, u8 *bytes);
63		63
64	static void drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr,	64	static void drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
65	struct drm_dp_mst_branch *mstb);	65	struct drm_dp_mst_branch *mstb);
66	static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr,	66	static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr,
67	struct drm_dp_mst_branch *mstb,	67	struct drm_dp_mst_branch *mstb,
68	struct drm_dp_mst_port *port);	68	struct drm_dp_mst_port *port);
69	static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr,	69	static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr,
70	u8 *guid);	70	u8 *guid);
71		71
72	static int drm_dp_mst_register_i2c_bus(struct drm_dp_aux *aux);	72	static int drm_dp_mst_register_i2c_bus(struct drm_dp_aux *aux);
73	static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_aux *aux);	73	static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_aux *aux);
74	static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr);	74	static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr);
75	/* sideband msg handling */	75	/* sideband msg handling */
76	static u8 drm_dp_msg_header_crc4(const uint8_t *data, size_t num_nibbles)	76	static u8 drm_dp_msg_header_crc4(const uint8_t *data, size_t num_nibbles)
77	{	77	{
78	u8 bitmask = 0x80;	78	u8 bitmask = 0x80;
79	u8 bitshift = 7;	79	u8 bitshift = 7;
80	u8 array_index = 0;	80	u8 array_index = 0;
81	int number_of_bits = num_nibbles * 4;	81	int number_of_bits = num_nibbles * 4;
82	u8 remainder = 0;	82	u8 remainder = 0;
83		83
84	while (number_of_bits != 0) {	84	while (number_of_bits != 0) {
85	number_of_bits--;	85	number_of_bits--;
86	remainder <<= 1;	86	remainder <<= 1;
87	remainder \|= (data[array_index] & bitmask) >> bitshift;	87	remainder \|= (data[array_index] & bitmask) >> bitshift;
88	bitmask >>= 1;	88	bitmask >>= 1;
89	bitshift--;	89	bitshift--;
90	if (bitmask == 0) {	90	if (bitmask == 0) {
91	bitmask = 0x80;	91	bitmask = 0x80;
92	bitshift = 7;	92	bitshift = 7;
93	array_index++;	93	array_index++;
94	}	94	}
95	if ((remainder & 0x10) == 0x10)	95	if ((remainder & 0x10) == 0x10)
96	remainder ^= 0x13;	96	remainder ^= 0x13;
97	}	97	}
98		98
99	number_of_bits = 4;	99	number_of_bits = 4;
100	while (number_of_bits != 0) {	100	while (number_of_bits != 0) {
101	number_of_bits--;	101	number_of_bits--;
102	remainder <<= 1;	102	remainder <<= 1;
103	if ((remainder & 0x10) != 0)	103	if ((remainder & 0x10) != 0)
104	remainder ^= 0x13;	104	remainder ^= 0x13;
105	}	105	}
106		106
107	return remainder;	107	return remainder;
108	}	108	}
109		109
110	static u8 drm_dp_msg_data_crc4(const uint8_t *data, u8 number_of_bytes)	110	static u8 drm_dp_msg_data_crc4(const uint8_t *data, u8 number_of_bytes)
111	{	111	{
112	u8 bitmask = 0x80;	112	u8 bitmask = 0x80;
113	u8 bitshift = 7;	113	u8 bitshift = 7;
114	u8 array_index = 0;	114	u8 array_index = 0;
115	int number_of_bits = number_of_bytes * 8;	115	int number_of_bits = number_of_bytes * 8;
116	u16 remainder = 0;	116	u16 remainder = 0;
117		117
118	while (number_of_bits != 0) {	118	while (number_of_bits != 0) {
119	number_of_bits--;	119	number_of_bits--;
120	remainder <<= 1;	120	remainder <<= 1;
121	remainder \|= (data[array_index] & bitmask) >> bitshift;	121	remainder \|= (data[array_index] & bitmask) >> bitshift;
122	bitmask >>= 1;	122	bitmask >>= 1;
123	bitshift--;	123	bitshift--;
124	if (bitmask == 0) {	124	if (bitmask == 0) {
125	bitmask = 0x80;	125	bitmask = 0x80;
126	bitshift = 7;	126	bitshift = 7;
127	array_index++;	127	array_index++;
128	}	128	}
129	if ((remainder & 0x100) == 0x100)	129	if ((remainder & 0x100) == 0x100)
130	remainder ^= 0xd5;	130	remainder ^= 0xd5;
131	}	131	}
132		132
133	number_of_bits = 8;	133	number_of_bits = 8;
134	while (number_of_bits != 0) {	134	while (number_of_bits != 0) {
135	number_of_bits--;	135	number_of_bits--;
136	remainder <<= 1;	136	remainder <<= 1;
137	if ((remainder & 0x100) != 0)	137	if ((remainder & 0x100) != 0)
138	remainder ^= 0xd5;	138	remainder ^= 0xd5;
139	}	139	}
140		140
141	return remainder & 0xff;	141	return remainder & 0xff;
142	}	142	}
143	static inline u8 drm_dp_calc_sb_hdr_size(struct drm_dp_sideband_msg_hdr *hdr)	143	static inline u8 drm_dp_calc_sb_hdr_size(struct drm_dp_sideband_msg_hdr *hdr)
144	{	144	{
145	u8 size = 3;	145	u8 size = 3;
146	size += (hdr->lct / 2);	146	size += (hdr->lct / 2);
147	return size;	147	return size;
148	}	148	}
149		149
150	static void drm_dp_encode_sideband_msg_hdr(struct drm_dp_sideband_msg_hdr *hdr,	150	static void drm_dp_encode_sideband_msg_hdr(struct drm_dp_sideband_msg_hdr *hdr,
151	u8 buf, int len)	151	u8 buf, int len)
152	{	152	{
153	int idx = 0;	153	int idx = 0;
154	int i;	154	int i;
155	u8 crc4;	155	u8 crc4;
156	buf[idx++] = ((hdr->lct & 0xf) << 4) \| (hdr->lcr & 0xf);	156	buf[idx++] = ((hdr->lct & 0xf) << 4) \| (hdr->lcr & 0xf);
157	for (i = 0; i < (hdr->lct / 2); i++)	157	for (i = 0; i < (hdr->lct / 2); i++)
158	buf[idx++] = hdr->rad[i];	158	buf[idx++] = hdr->rad[i];
159	buf[idx++] = (hdr->broadcast << 7) \| (hdr->path_msg << 6) \|	159	buf[idx++] = (hdr->broadcast << 7) \| (hdr->path_msg << 6) \|
160	(hdr->msg_len & 0x3f);	160	(hdr->msg_len & 0x3f);
161	buf[idx++] = (hdr->somt << 7) \| (hdr->eomt << 6) \| (hdr->seqno << 4);	161	buf[idx++] = (hdr->somt << 7) \| (hdr->eomt << 6) \| (hdr->seqno << 4);
162		162
163	crc4 = drm_dp_msg_header_crc4(buf, (idx * 2) - 1);	163	crc4 = drm_dp_msg_header_crc4(buf, (idx * 2) - 1);
164	buf[idx - 1] \|= (crc4 & 0xf);	164	buf[idx - 1] \|= (crc4 & 0xf);
165		165
166	*len = idx;	166	*len = idx;
167	}	167	}
168		168
169	static bool drm_dp_decode_sideband_msg_hdr(struct drm_dp_sideband_msg_hdr *hdr,	169	static bool drm_dp_decode_sideband_msg_hdr(struct drm_dp_sideband_msg_hdr *hdr,
170	u8 buf, int buflen, u8 hdrlen)	170	u8 buf, int buflen, u8 hdrlen)
171	{	171	{
172	u8 crc4;	172	u8 crc4;
173	u8 len;	173	u8 len;
174	int i;	174	int i;
175	u8 idx;	175	u8 idx;
176	if (buf[0] == 0)	176	if (buf[0] == 0)
177	return false;	177	return false;
178	len = 3;	178	len = 3;
179	len += ((buf[0] & 0xf0) >> 4) / 2;	179	len += ((buf[0] & 0xf0) >> 4) / 2;
180	if (len > buflen)	180	if (len > buflen)
181	return false;	181	return false;
182	crc4 = drm_dp_msg_header_crc4(buf, (len * 2) - 1);	182	crc4 = drm_dp_msg_header_crc4(buf, (len * 2) - 1);
183		183
184	if ((crc4 & 0xf) != (buf[len - 1] & 0xf)) {	184	if ((crc4 & 0xf) != (buf[len - 1] & 0xf)) {
185	DRM_DEBUG_KMS("crc4 mismatch 0x%x 0x%x\n", crc4, buf[len - 1]);	185	DRM_DEBUG_KMS("crc4 mismatch 0x%x 0x%x\n", crc4, buf[len - 1]);
186	return false;	186	return false;
187	}	187	}
188		188
189	hdr->lct = (buf[0] & 0xf0) >> 4;	189	hdr->lct = (buf[0] & 0xf0) >> 4;
190	hdr->lcr = (buf[0] & 0xf);	190	hdr->lcr = (buf[0] & 0xf);
191	idx = 1;	191	idx = 1;
192	for (i = 0; i < (hdr->lct / 2); i++)	192	for (i = 0; i < (hdr->lct / 2); i++)
193	hdr->rad[i] = buf[idx++];	193	hdr->rad[i] = buf[idx++];
194	hdr->broadcast = (buf[idx] >> 7) & 0x1;	194	hdr->broadcast = (buf[idx] >> 7) & 0x1;
195	hdr->path_msg = (buf[idx] >> 6) & 0x1;	195	hdr->path_msg = (buf[idx] >> 6) & 0x1;
196	hdr->msg_len = buf[idx] & 0x3f;	196	hdr->msg_len = buf[idx] & 0x3f;
197	idx++;	197	idx++;
198	hdr->somt = (buf[idx] >> 7) & 0x1;	198	hdr->somt = (buf[idx] >> 7) & 0x1;
199	hdr->eomt = (buf[idx] >> 6) & 0x1;	199	hdr->eomt = (buf[idx] >> 6) & 0x1;
200	hdr->seqno = (buf[idx] >> 4) & 0x1;	200	hdr->seqno = (buf[idx] >> 4) & 0x1;
201	idx++;	201	idx++;
202	*hdrlen = idx;	202	*hdrlen = idx;
203	return true;	203	return true;
204	}	204	}
205		205
206	static void drm_dp_encode_sideband_req(struct drm_dp_sideband_msg_req_body *req,	206	static void drm_dp_encode_sideband_req(struct drm_dp_sideband_msg_req_body *req,
207	struct drm_dp_sideband_msg_tx *raw)	207	struct drm_dp_sideband_msg_tx *raw)
208	{	208	{
209	int idx = 0;	209	int idx = 0;
210	int i;	210	int i;
211	u8 *buf = raw->msg;	211	u8 *buf = raw->msg;
212	buf[idx++] = req->req_type & 0x7f;	212	buf[idx++] = req->req_type & 0x7f;
213		213
214	switch (req->req_type) {	214	switch (req->req_type) {
215	case DP_ENUM_PATH_RESOURCES:	215	case DP_ENUM_PATH_RESOURCES:
216	buf[idx] = (req->u.port_num.port_number & 0xf) << 4;	216	buf[idx] = (req->u.port_num.port_number & 0xf) << 4;
217	idx++;	217	idx++;
218	break;	218	break;
219	case DP_ALLOCATE_PAYLOAD:	219	case DP_ALLOCATE_PAYLOAD:
220	buf[idx] = (req->u.allocate_payload.port_number & 0xf) << 4 \|	220	buf[idx] = (req->u.allocate_payload.port_number & 0xf) << 4 \|
221	(req->u.allocate_payload.number_sdp_streams & 0xf);	221	(req->u.allocate_payload.number_sdp_streams & 0xf);
222	idx++;	222	idx++;
223	buf[idx] = (req->u.allocate_payload.vcpi & 0x7f);	223	buf[idx] = (req->u.allocate_payload.vcpi & 0x7f);
224	idx++;	224	idx++;
225	buf[idx] = (req->u.allocate_payload.pbn >> 8);	225	buf[idx] = (req->u.allocate_payload.pbn >> 8);
226	idx++;	226	idx++;
227	buf[idx] = (req->u.allocate_payload.pbn & 0xff);	227	buf[idx] = (req->u.allocate_payload.pbn & 0xff);
228	idx++;	228	idx++;
229	for (i = 0; i < req->u.allocate_payload.number_sdp_streams / 2; i++) {	229	for (i = 0; i < req->u.allocate_payload.number_sdp_streams / 2; i++) {
230	buf[idx] = ((req->u.allocate_payload.sdp_stream_sink[i * 2] & 0xf) << 4) \|	230	buf[idx] = ((req->u.allocate_payload.sdp_stream_sink[i * 2] & 0xf) << 4) \|
231	(req->u.allocate_payload.sdp_stream_sink[i * 2 + 1] & 0xf);	231	(req->u.allocate_payload.sdp_stream_sink[i * 2 + 1] & 0xf);
232	idx++;	232	idx++;
233	}	233	}
234	if (req->u.allocate_payload.number_sdp_streams & 1) {	234	if (req->u.allocate_payload.number_sdp_streams & 1) {
235	i = req->u.allocate_payload.number_sdp_streams - 1;	235	i = req->u.allocate_payload.number_sdp_streams - 1;
236	buf[idx] = (req->u.allocate_payload.sdp_stream_sink[i] & 0xf) << 4;	236	buf[idx] = (req->u.allocate_payload.sdp_stream_sink[i] & 0xf) << 4;
237	idx++;	237	idx++;
238	}	238	}
239	break;	239	break;
240	case DP_QUERY_PAYLOAD:	240	case DP_QUERY_PAYLOAD:
241	buf[idx] = (req->u.query_payload.port_number & 0xf) << 4;	241	buf[idx] = (req->u.query_payload.port_number & 0xf) << 4;
242	idx++;	242	idx++;
243	buf[idx] = (req->u.query_payload.vcpi & 0x7f);	243	buf[idx] = (req->u.query_payload.vcpi & 0x7f);
244	idx++;	244	idx++;
245	break;	245	break;
246	case DP_REMOTE_DPCD_READ:	246	case DP_REMOTE_DPCD_READ:
247	buf[idx] = (req->u.dpcd_read.port_number & 0xf) << 4;	247	buf[idx] = (req->u.dpcd_read.port_number & 0xf) << 4;
248	buf[idx] \|= ((req->u.dpcd_read.dpcd_address & 0xf0000) >> 16) & 0xf;	248	buf[idx] \|= ((req->u.dpcd_read.dpcd_address & 0xf0000) >> 16) & 0xf;
249	idx++;	249	idx++;
250	buf[idx] = (req->u.dpcd_read.dpcd_address & 0xff00) >> 8;	250	buf[idx] = (req->u.dpcd_read.dpcd_address & 0xff00) >> 8;
251	idx++;	251	idx++;
252	buf[idx] = (req->u.dpcd_read.dpcd_address & 0xff);	252	buf[idx] = (req->u.dpcd_read.dpcd_address & 0xff);
253	idx++;	253	idx++;
254	buf[idx] = (req->u.dpcd_read.num_bytes);	254	buf[idx] = (req->u.dpcd_read.num_bytes);
255	idx++;	255	idx++;
256	break;	256	break;
257		257
258	case DP_REMOTE_DPCD_WRITE:	258	case DP_REMOTE_DPCD_WRITE:
259	buf[idx] = (req->u.dpcd_write.port_number & 0xf) << 4;	259	buf[idx] = (req->u.dpcd_write.port_number & 0xf) << 4;
260	buf[idx] \|= ((req->u.dpcd_write.dpcd_address & 0xf0000) >> 16) & 0xf;	260	buf[idx] \|= ((req->u.dpcd_write.dpcd_address & 0xf0000) >> 16) & 0xf;
261	idx++;	261	idx++;
262	buf[idx] = (req->u.dpcd_write.dpcd_address & 0xff00) >> 8;	262	buf[idx] = (req->u.dpcd_write.dpcd_address & 0xff00) >> 8;
263	idx++;	263	idx++;
264	buf[idx] = (req->u.dpcd_write.dpcd_address & 0xff);	264	buf[idx] = (req->u.dpcd_write.dpcd_address & 0xff);
265	idx++;	265	idx++;
266	buf[idx] = (req->u.dpcd_write.num_bytes);	266	buf[idx] = (req->u.dpcd_write.num_bytes);
267	idx++;	267	idx++;
268	memcpy(&buf[idx], req->u.dpcd_write.bytes, req->u.dpcd_write.num_bytes);	268	memcpy(&buf[idx], req->u.dpcd_write.bytes, req->u.dpcd_write.num_bytes);
269	idx += req->u.dpcd_write.num_bytes;	269	idx += req->u.dpcd_write.num_bytes;
270	break;	270	break;
271	case DP_REMOTE_I2C_READ:	271	case DP_REMOTE_I2C_READ:
272	buf[idx] = (req->u.i2c_read.port_number & 0xf) << 4;	272	buf[idx] = (req->u.i2c_read.port_number & 0xf) << 4;
273	buf[idx] \|= (req->u.i2c_read.num_transactions & 0x3);	273	buf[idx] \|= (req->u.i2c_read.num_transactions & 0x3);
274	idx++;	274	idx++;
275	for (i = 0; i < (req->u.i2c_read.num_transactions & 0x3); i++) {	275	for (i = 0; i < (req->u.i2c_read.num_transactions & 0x3); i++) {
276	buf[idx] = req->u.i2c_read.transactions[i].i2c_dev_id & 0x7f;	276	buf[idx] = req->u.i2c_read.transactions[i].i2c_dev_id & 0x7f;
277	idx++;	277	idx++;
278	buf[idx] = req->u.i2c_read.transactions[i].num_bytes;	278	buf[idx] = req->u.i2c_read.transactions[i].num_bytes;
279	idx++;	279	idx++;
280	memcpy(&buf[idx], req->u.i2c_read.transactions[i].bytes, req->u.i2c_read.transactions[i].num_bytes);	280	memcpy(&buf[idx], req->u.i2c_read.transactions[i].bytes, req->u.i2c_read.transactions[i].num_bytes);
281	idx += req->u.i2c_read.transactions[i].num_bytes;	281	idx += req->u.i2c_read.transactions[i].num_bytes;
282		282
283	buf[idx] = (req->u.i2c_read.transactions[i].no_stop_bit & 0x1) << 5;	283	buf[idx] = (req->u.i2c_read.transactions[i].no_stop_bit & 0x1) << 5;
284	buf[idx] \|= (req->u.i2c_read.transactions[i].i2c_transaction_delay & 0xf);	284	buf[idx] \|= (req->u.i2c_read.transactions[i].i2c_transaction_delay & 0xf);
285	idx++;	285	idx++;
286	}	286	}
287	buf[idx] = (req->u.i2c_read.read_i2c_device_id) & 0x7f;	287	buf[idx] = (req->u.i2c_read.read_i2c_device_id) & 0x7f;
288	idx++;	288	idx++;
289	buf[idx] = (req->u.i2c_read.num_bytes_read);	289	buf[idx] = (req->u.i2c_read.num_bytes_read);
290	idx++;	290	idx++;
291	break;	291	break;
292		292
293	case DP_REMOTE_I2C_WRITE:	293	case DP_REMOTE_I2C_WRITE:
294	buf[idx] = (req->u.i2c_write.port_number & 0xf) << 4;	294	buf[idx] = (req->u.i2c_write.port_number & 0xf) << 4;
295	idx++;	295	idx++;
296	buf[idx] = (req->u.i2c_write.write_i2c_device_id) & 0x7f;	296	buf[idx] = (req->u.i2c_write.write_i2c_device_id) & 0x7f;
297	idx++;	297	idx++;
298	buf[idx] = (req->u.i2c_write.num_bytes);	298	buf[idx] = (req->u.i2c_write.num_bytes);
299	idx++;	299	idx++;
300	memcpy(&buf[idx], req->u.i2c_write.bytes, req->u.i2c_write.num_bytes);	300	memcpy(&buf[idx], req->u.i2c_write.bytes, req->u.i2c_write.num_bytes);
301	idx += req->u.i2c_write.num_bytes;	301	idx += req->u.i2c_write.num_bytes;
302	break;	302	break;
303	}	303	}
304	raw->cur_len = idx;	304	raw->cur_len = idx;
305	}	305	}
306		306
307	static void drm_dp_crc_sideband_chunk_req(u8 *msg, u8 len)	307	static void drm_dp_crc_sideband_chunk_req(u8 *msg, u8 len)
308	{	308	{
309	u8 crc4;	309	u8 crc4;
310	crc4 = drm_dp_msg_data_crc4(msg, len);	310	crc4 = drm_dp_msg_data_crc4(msg, len);
311	msg[len] = crc4;	311	msg[len] = crc4;
312	}	312	}
313		313
314	static void drm_dp_encode_sideband_reply(struct drm_dp_sideband_msg_reply_body *rep,	314	static void drm_dp_encode_sideband_reply(struct drm_dp_sideband_msg_reply_body *rep,
315	struct drm_dp_sideband_msg_tx *raw)	315	struct drm_dp_sideband_msg_tx *raw)
316	{	316	{
317	int idx = 0;	317	int idx = 0;
318	u8 *buf = raw->msg;	318	u8 *buf = raw->msg;
319		319
320	buf[idx++] = (rep->reply_type & 0x1) << 7 \| (rep->req_type & 0x7f);	320	buf[idx++] = (rep->reply_type & 0x1) << 7 \| (rep->req_type & 0x7f);
321		321
322	raw->cur_len = idx;	322	raw->cur_len = idx;
323	}	323	}
324		324
325	/* this adds a chunk of msg to the builder to get the final msg */	325	/* this adds a chunk of msg to the builder to get the final msg */
326	static bool drm_dp_sideband_msg_build(struct drm_dp_sideband_msg_rx *msg,	326	static bool drm_dp_sideband_msg_build(struct drm_dp_sideband_msg_rx *msg,
327	u8 *replybuf, u8 replybuflen, bool hdr)	327	u8 *replybuf, u8 replybuflen, bool hdr)
328	{	328	{
329	int ret;	329	int ret;
330	u8 crc4;	330	u8 crc4;
331		331
332	if (hdr) {	332	if (hdr) {
333	u8 hdrlen;	333	u8 hdrlen;
334	struct drm_dp_sideband_msg_hdr recv_hdr;	334	struct drm_dp_sideband_msg_hdr recv_hdr;
335	ret = drm_dp_decode_sideband_msg_hdr(&recv_hdr, replybuf, replybuflen, &hdrlen);	335	ret = drm_dp_decode_sideband_msg_hdr(&recv_hdr, replybuf, replybuflen, &hdrlen);
336	if (ret == false) {	336	if (ret == false) {
337	print_hex_dump(KERN_DEBUG, "failed hdr", DUMP_PREFIX_NONE, 16, 1, replybuf, replybuflen, false);	337	print_hex_dump(KERN_DEBUG, "failed hdr", DUMP_PREFIX_NONE, 16, 1, replybuf, replybuflen, false);
338	return false;	338	return false;
339	}	339	}
340		340
341	/* get length contained in this portion */	341	/* get length contained in this portion */
342	msg->curchunk_len = recv_hdr.msg_len;	342	msg->curchunk_len = recv_hdr.msg_len;
343	msg->curchunk_hdrlen = hdrlen;	343	msg->curchunk_hdrlen = hdrlen;
344		344
345	/* we have already gotten an somt - don't bother parsing */	345	/* we have already gotten an somt - don't bother parsing */
346	if (recv_hdr.somt && msg->have_somt)	346	if (recv_hdr.somt && msg->have_somt)
347	return false;	347	return false;
348		348
349	if (recv_hdr.somt) {	349	if (recv_hdr.somt) {
350	memcpy(&msg->initial_hdr, &recv_hdr, sizeof(struct drm_dp_sideband_msg_hdr));	350	memcpy(&msg->initial_hdr, &recv_hdr, sizeof(struct drm_dp_sideband_msg_hdr));
351	msg->have_somt = true;	351	msg->have_somt = true;
352	}	352	}
353	if (recv_hdr.eomt)	353	if (recv_hdr.eomt)
354	msg->have_eomt = true;	354	msg->have_eomt = true;
355		355
356	/* copy the bytes for the remainder of this header chunk */	356	/* copy the bytes for the remainder of this header chunk */
357	msg->curchunk_idx = min(msg->curchunk_len, (u8)(replybuflen - hdrlen));	357	msg->curchunk_idx = min(msg->curchunk_len, (u8)(replybuflen - hdrlen));
358	memcpy(&msg->chunk[0], replybuf + hdrlen, msg->curchunk_idx);	358	memcpy(&msg->chunk[0], replybuf + hdrlen, msg->curchunk_idx);
359	} else {	359	} else {
360	memcpy(&msg->chunk[msg->curchunk_idx], replybuf, replybuflen);	360	memcpy(&msg->chunk[msg->curchunk_idx], replybuf, replybuflen);
361	msg->curchunk_idx += replybuflen;	361	msg->curchunk_idx += replybuflen;
362	}	362	}
363		363
364	if (msg->curchunk_idx >= msg->curchunk_len) {	364	if (msg->curchunk_idx >= msg->curchunk_len) {
365	/* do CRC */	365	/* do CRC */
366	crc4 = drm_dp_msg_data_crc4(msg->chunk, msg->curchunk_len - 1);	366	crc4 = drm_dp_msg_data_crc4(msg->chunk, msg->curchunk_len - 1);
367	/* copy chunk into bigger msg */	367	/* copy chunk into bigger msg */
368	memcpy(&msg->msg[msg->curlen], msg->chunk, msg->curchunk_len - 1);	368	memcpy(&msg->msg[msg->curlen], msg->chunk, msg->curchunk_len - 1);
369	msg->curlen += msg->curchunk_len - 1;	369	msg->curlen += msg->curchunk_len - 1;
370	}	370	}
371	return true;	371	return true;
372	}	372	}
373		373
374	static bool drm_dp_sideband_parse_link_address(struct drm_dp_sideband_msg_rx *raw,	374	static bool drm_dp_sideband_parse_link_address(struct drm_dp_sideband_msg_rx *raw,
375	struct drm_dp_sideband_msg_reply_body *repmsg)	375	struct drm_dp_sideband_msg_reply_body *repmsg)
376	{	376	{
377	int idx = 1;	377	int idx = 1;
378	int i;	378	int i;
379	memcpy(repmsg->u.link_addr.guid, &raw->msg[idx], 16);	379	memcpy(repmsg->u.link_addr.guid, &raw->msg[idx], 16);
380	idx += 16;	380	idx += 16;
381	repmsg->u.link_addr.nports = raw->msg[idx] & 0xf;	381	repmsg->u.link_addr.nports = raw->msg[idx] & 0xf;
382	idx++;	382	idx++;
383	if (idx > raw->curlen)	383	if (idx > raw->curlen)
384	goto fail_len;	384	goto fail_len;
385	for (i = 0; i < repmsg->u.link_addr.nports; i++) {	385	for (i = 0; i < repmsg->u.link_addr.nports; i++) {
386	if (raw->msg[idx] & 0x80)	386	if (raw->msg[idx] & 0x80)
387	repmsg->u.link_addr.ports[i].input_port = 1;	387	repmsg->u.link_addr.ports[i].input_port = 1;
388		388
389	repmsg->u.link_addr.ports[i].peer_device_type = (raw->msg[idx] >> 4) & 0x7;	389	repmsg->u.link_addr.ports[i].peer_device_type = (raw->msg[idx] >> 4) & 0x7;
390	repmsg->u.link_addr.ports[i].port_number = (raw->msg[idx] & 0xf);	390	repmsg->u.link_addr.ports[i].port_number = (raw->msg[idx] & 0xf);
391		391
392	idx++;	392	idx++;
393	if (idx > raw->curlen)	393	if (idx > raw->curlen)
394	goto fail_len;	394	goto fail_len;
395	repmsg->u.link_addr.ports[i].mcs = (raw->msg[idx] >> 7) & 0x1;	395	repmsg->u.link_addr.ports[i].mcs = (raw->msg[idx] >> 7) & 0x1;
396	repmsg->u.link_addr.ports[i].ddps = (raw->msg[idx] >> 6) & 0x1;	396	repmsg->u.link_addr.ports[i].ddps = (raw->msg[idx] >> 6) & 0x1;
397	if (repmsg->u.link_addr.ports[i].input_port == 0)	397	if (repmsg->u.link_addr.ports[i].input_port == 0)
398	repmsg->u.link_addr.ports[i].legacy_device_plug_status = (raw->msg[idx] >> 5) & 0x1;	398	repmsg->u.link_addr.ports[i].legacy_device_plug_status = (raw->msg[idx] >> 5) & 0x1;
399	idx++;	399	idx++;
400	if (idx > raw->curlen)	400	if (idx > raw->curlen)
401	goto fail_len;	401	goto fail_len;
402	if (repmsg->u.link_addr.ports[i].input_port == 0) {	402	if (repmsg->u.link_addr.ports[i].input_port == 0) {
403	repmsg->u.link_addr.ports[i].dpcd_revision = (raw->msg[idx]);	403	repmsg->u.link_addr.ports[i].dpcd_revision = (raw->msg[idx]);
404	idx++;	404	idx++;
405	if (idx > raw->curlen)	405	if (idx > raw->curlen)
406	goto fail_len;	406	goto fail_len;
407	memcpy(repmsg->u.link_addr.ports[i].peer_guid, &raw->msg[idx], 16);	407	memcpy(repmsg->u.link_addr.ports[i].peer_guid, &raw->msg[idx], 16);
408	idx += 16;	408	idx += 16;
409	if (idx > raw->curlen)	409	if (idx > raw->curlen)
410	goto fail_len;	410	goto fail_len;
411	repmsg->u.link_addr.ports[i].num_sdp_streams = (raw->msg[idx] >> 4) & 0xf;	411	repmsg->u.link_addr.ports[i].num_sdp_streams = (raw->msg[idx] >> 4) & 0xf;
412	repmsg->u.link_addr.ports[i].num_sdp_stream_sinks = (raw->msg[idx] & 0xf);	412	repmsg->u.link_addr.ports[i].num_sdp_stream_sinks = (raw->msg[idx] & 0xf);
413	idx++;	413	idx++;
414		414
415	}	415	}
416	if (idx > raw->curlen)	416	if (idx > raw->curlen)
417	goto fail_len;	417	goto fail_len;
418	}	418	}
419		419
420	return true;	420	return true;
421	fail_len:	421	fail_len:
422	DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx, raw->curlen);	422	DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx, raw->curlen);
423	return false;	423	return false;
424	}	424	}
425		425
426	static bool drm_dp_sideband_parse_remote_dpcd_read(struct drm_dp_sideband_msg_rx *raw,	426	static bool drm_dp_sideband_parse_remote_dpcd_read(struct drm_dp_sideband_msg_rx *raw,
427	struct drm_dp_sideband_msg_reply_body *repmsg)	427	struct drm_dp_sideband_msg_reply_body *repmsg)
428	{	428	{
429	int idx = 1;	429	int idx = 1;
430	repmsg->u.remote_dpcd_read_ack.port_number = raw->msg[idx] & 0xf;	430	repmsg->u.remote_dpcd_read_ack.port_number = raw->msg[idx] & 0xf;
431	idx++;	431	idx++;
432	if (idx > raw->curlen)	432	if (idx > raw->curlen)
433	goto fail_len;	433	goto fail_len;
434	repmsg->u.remote_dpcd_read_ack.num_bytes = raw->msg[idx];	434	repmsg->u.remote_dpcd_read_ack.num_bytes = raw->msg[idx];
435	if (idx > raw->curlen)	435	if (idx > raw->curlen)
436	goto fail_len;	436	goto fail_len;
437		437
438	memcpy(repmsg->u.remote_dpcd_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_dpcd_read_ack.num_bytes);	438	memcpy(repmsg->u.remote_dpcd_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_dpcd_read_ack.num_bytes);
439	return true;	439	return true;
440	fail_len:	440	fail_len:
441	DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx, raw->curlen);	441	DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx, raw->curlen);
442	return false;	442	return false;
443	}	443	}
444		444
445	static bool drm_dp_sideband_parse_remote_dpcd_write(struct drm_dp_sideband_msg_rx *raw,	445	static bool drm_dp_sideband_parse_remote_dpcd_write(struct drm_dp_sideband_msg_rx *raw,
446	struct drm_dp_sideband_msg_reply_body *repmsg)	446	struct drm_dp_sideband_msg_reply_body *repmsg)
447	{	447	{
448	int idx = 1;	448	int idx = 1;
449	repmsg->u.remote_dpcd_write_ack.port_number = raw->msg[idx] & 0xf;	449	repmsg->u.remote_dpcd_write_ack.port_number = raw->msg[idx] & 0xf;
450	idx++;	450	idx++;
451	if (idx > raw->curlen)	451	if (idx > raw->curlen)
452	goto fail_len;	452	goto fail_len;
453	return true;	453	return true;
454	fail_len:	454	fail_len:
455	DRM_DEBUG_KMS("parse length fail %d %d\n", idx, raw->curlen);	455	DRM_DEBUG_KMS("parse length fail %d %d\n", idx, raw->curlen);
456	return false;	456	return false;
457	}	457	}
458		458
459	static bool drm_dp_sideband_parse_remote_i2c_read_ack(struct drm_dp_sideband_msg_rx *raw,	459	static bool drm_dp_sideband_parse_remote_i2c_read_ack(struct drm_dp_sideband_msg_rx *raw,
460	struct drm_dp_sideband_msg_reply_body *repmsg)	460	struct drm_dp_sideband_msg_reply_body *repmsg)
461	{	461	{
462	int idx = 1;	462	int idx = 1;
463		463
464	repmsg->u.remote_i2c_read_ack.port_number = (raw->msg[idx] & 0xf);	464	repmsg->u.remote_i2c_read_ack.port_number = (raw->msg[idx] & 0xf);
465	idx++;	465	idx++;
466	if (idx > raw->curlen)	466	if (idx > raw->curlen)
467	goto fail_len;	467	goto fail_len;
468	repmsg->u.remote_i2c_read_ack.num_bytes = raw->msg[idx];	468	repmsg->u.remote_i2c_read_ack.num_bytes = raw->msg[idx];
469	idx++;	469	idx++;
470	/* TODO check */	470	/* TODO check */
471	memcpy(repmsg->u.remote_i2c_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_i2c_read_ack.num_bytes);	471	memcpy(repmsg->u.remote_i2c_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_i2c_read_ack.num_bytes);
472	return true;	472	return true;
473	fail_len:	473	fail_len:
474	DRM_DEBUG_KMS("remote i2c reply parse length fail %d %d\n", idx, raw->curlen);	474	DRM_DEBUG_KMS("remote i2c reply parse length fail %d %d\n", idx, raw->curlen);
475	return false;	475	return false;
476	}	476	}
477		477
478	static bool drm_dp_sideband_parse_enum_path_resources_ack(struct drm_dp_sideband_msg_rx *raw,	478	static bool drm_dp_sideband_parse_enum_path_resources_ack(struct drm_dp_sideband_msg_rx *raw,
479	struct drm_dp_sideband_msg_reply_body *repmsg)	479	struct drm_dp_sideband_msg_reply_body *repmsg)
480	{	480	{
481	int idx = 1;	481	int idx = 1;
482	repmsg->u.path_resources.port_number = (raw->msg[idx] >> 4) & 0xf;	482	repmsg->u.path_resources.port_number = (raw->msg[idx] >> 4) & 0xf;
483	idx++;	483	idx++;
484	if (idx > raw->curlen)	484	if (idx > raw->curlen)
485	goto fail_len;	485	goto fail_len;
486	repmsg->u.path_resources.full_payload_bw_number = (raw->msg[idx] << 8) \| (raw->msg[idx+1]);	486	repmsg->u.path_resources.full_payload_bw_number = (raw->msg[idx] << 8) \| (raw->msg[idx+1]);
487	idx += 2;	487	idx += 2;
488	if (idx > raw->curlen)	488	if (idx > raw->curlen)
489	goto fail_len;	489	goto fail_len;
490	repmsg->u.path_resources.avail_payload_bw_number = (raw->msg[idx] << 8) \| (raw->msg[idx+1]);	490	repmsg->u.path_resources.avail_payload_bw_number = (raw->msg[idx] << 8) \| (raw->msg[idx+1]);
491	idx += 2;	491	idx += 2;
492	if (idx > raw->curlen)	492	if (idx > raw->curlen)
493	goto fail_len;	493	goto fail_len;
494	return true;	494	return true;
495	fail_len:	495	fail_len:
496	DRM_DEBUG_KMS("enum resource parse length fail %d %d\n", idx, raw->curlen);	496	DRM_DEBUG_KMS("enum resource parse length fail %d %d\n", idx, raw->curlen);
497	return false;	497	return false;
498	}	498	}
499		499
500	static bool drm_dp_sideband_parse_allocate_payload_ack(struct drm_dp_sideband_msg_rx *raw,	500	static bool drm_dp_sideband_parse_allocate_payload_ack(struct drm_dp_sideband_msg_rx *raw,

Subversion Repositories Kolibri OS

(root)/drivers/video/drm/drm_dp_mst_topology.c @ 6935 – Rev 6320 → 6660