0,0 → 1,2666 |
/* |
* 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 <linux/kernel.h> |
#include <linux/mutex.h> |
#include <linux/kref.h> |
#include <linux/wait.h> |
#include <linux/workqueue.h> |
#include <linux/delay.h> |
#include <linux/errno.h> |
#include <linux/sched.h> |
#include <linux/seq_file.h> |
#include <linux/i2c.h> |
#include <drm/drm_dp_mst_helper.h> |
#include <drm/drmP.h> |
|
#include <drm/drm_fixed.h> |
|
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 int 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; |
|
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; |
} |
|
set_bit(ret, &mgr->payload_mask); |
vcpi->vcpi = ret; |
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 id) |
{ |
if (id == 0) |
return; |
|
mutex_lock(&mgr->payload_lock); |
DRM_DEBUG_KMS("putting payload %d\n", id); |
clear_bit(id, &mgr->payload_mask); |
mgr->proposed_vcpis[id - 1] = NULL; |
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; |
mutex_lock(&mgr->qlock); |
ret = (txmsg->state == DRM_DP_SIDEBAND_TX_RX || |
txmsg->state == DRM_DP_SIDEBAND_TX_TIMEOUT); |
mutex_unlock(&mgr->qlock); |
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_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; |
|
cancel_work_sync(&mstb->mgr->work); |
|
/* |
* 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); |
kfree(mstb); |
} |
|
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) |
{ |
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: |
drm_dp_put_mst_branch_device(port->mstb); |
port->mstb = NULL; |
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; |
if (port->connector) |
(*port->mgr->cbs->destroy_connector)(mgr, port->connector); |
drm_dp_port_teardown_pdt(port, port->pdt); |
|
if (!port->input && port->vcpi.vcpi > 0) |
drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi); |
} |
kfree(port); |
|
(*mgr->cbs->hotplug)(mgr); |
} |
|
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 lct = port->parent->lct; |
int shift = 4; |
int idx = lct / 2; |
if (lct > 1) { |
memcpy(rad, port->parent->rad, idx); |
shift = (lct % 2) ? 4 : 0; |
} else |
rad[0] = 0; |
|
rad[idx] |= port->port_num << shift; |
return 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_port_guid(struct drm_dp_mst_branch *mstb, |
struct drm_dp_mst_port *port) |
{ |
int ret; |
if (port->dpcd_rev >= 0x12) { |
port->guid_valid = drm_dp_validate_guid(mstb->mgr, port->guid); |
if (!port->guid_valid) { |
ret = drm_dp_send_dpcd_write(mstb->mgr, |
port, |
DP_GUID, |
16, port->guid); |
port->guid_valid = true; |
} |
} |
} |
|
static void build_mst_prop_path(struct drm_dp_mst_port *port, |
struct drm_dp_mst_branch *mstb, |
char *proppath) |
{ |
int i; |
char temp[8]; |
snprintf(proppath, 255, "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; |
snprintf(temp, 8, "-%d", port_num); |
strncat(proppath, temp, 255); |
} |
snprintf(temp, 8, "-%d", port->port_num); |
strncat(proppath, temp, 255); |
} |
|
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; |
memcpy(port->guid, port_msg->peer_guid, 16); |
|
/* 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) { |
drm_dp_check_port_guid(mstb, port); |
if (!port->input) |
drm_dp_send_enum_path_resources(mstb->mgr, mstb, port); |
} else { |
port->guid_valid = false; |
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); |
port->mstb->link_address_sent = true; |
} |
} |
|
if (created && !port->input) { |
char proppath[255]; |
build_mst_prop_path(port, mstb, proppath); |
port->connector = (*mstb->mgr->cbs->add_connector)(mstb->mgr, port, proppath); |
} |
|
/* 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) { |
drm_dp_check_port_guid(mstb, port); |
dowork = true; |
} else { |
port->guid_valid = false; |
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 */ |
mstb = mgr->mst_primary; |
|
for (i = 0; i < lct - 1; i++) { |
int shift = (i % 2) ? 0 : 4; |
int port_num = rad[i / 2] >> shift; |
|
list_for_each_entry(port, &mstb->ports, next) { |
if (port->port_num == port_num) { |
if (!port->mstb) { |
DRM_ERROR("failed to lookup MSTB with lct %d, rad %02x\n", lct, rad[0]); |
return NULL; |
} |
|
mstb = port->mstb; |
break; |
} |
} |
} |
kref_get(&mstb->kref); |
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; |
|
if (!mstb->link_address_sent) { |
drm_dp_send_link_address(mgr, mstb); |
mstb->link_address_sent = true; |
} |
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) |
drm_dp_check_and_send_link_address(mgr, port->mstb); |
} |
} |
|
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); |
|
drm_dp_check_and_send_link_address(mgr, mgr->mst_primary); |
|
} |
|
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); |
WARN(1, "fail\n"); |
|
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; |
|
/* 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; |
} |
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; |
} |
|
/* must be called holding qlock */ |
static void process_single_down_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 */ |
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 */ |
if (list_empty(&mgr->tx_msg_upq)) { |
mgr->tx_up_in_progress = false; |
return; |
} |
|
txmsg = list_first_entry(&mgr->tx_msg_upq, struct drm_dp_sideband_msg_tx, next); |
ret = process_single_tx_qlock(mgr, txmsg, true); |
if (ret == 1) { |
/* up txmsgs aren't put in slots - so free after we send it */ |
list_del(&txmsg->next); |
kfree(txmsg); |
} else if (ret) |
DRM_DEBUG_KMS("failed to send msg in q %d\n", ret); |
mgr->tx_up_in_progress = true; |
} |
|
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 int 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 -ENOMEM; |
|
txmsg->dst = mstb; |
len = build_link_address(txmsg); |
|
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); |
} |
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 |
DRM_DEBUG_KMS("link address failed %d\n", ret); |
|
kfree(txmsg); |
return 0; |
} |
|
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 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; |
|
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; |
} |
|
txmsg->dst = mstb; |
len = build_allocate_payload(txmsg, port->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); |
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 = 0; |
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; |
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); |
req_payload.num_slots = mgr->proposed_vcpis[i]->num_slots; |
} else { |
port = NULL; |
req_payload.num_slots = 0; |
} |
/* work out what is required to happen with this payload */ |
if (mgr->payloads[i].start_slot != req_payload.start_slot || |
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, i + 1, &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, i + 1, &mgr->payloads[i]); |
req_payload.payload_state = mgr->payloads[i].payload_state; |
} else |
req_payload.payload_state = 0; |
|
mgr->payloads[i].start_slot = req_payload.start_slot; |
mgr->payloads[i].payload_state = req_payload.payload_state; |
} |
cur_slots += req_payload.num_slots; |
} |
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, i + 1, &mgr->payloads[i]); |
} else if (mgr->payloads[i].payload_state == DP_PAYLOAD_DELETE_LOCAL) { |
ret = drm_dp_destroy_payload_step2(mgr, i + 1, &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); |
list_add_tail(&txmsg->next, &mgr->tx_msg_upq); |
if (!mgr->tx_up_in_progress) { |
process_single_up_tx_qlock(mgr); |
} |
mutex_unlock(&mgr->qlock); |
return 0; |
} |
|
static int drm_dp_get_vc_payload_bw(int dp_link_bw, int dp_link_count) |
{ |
switch (dp_link_bw) { |
case DP_LINK_BW_1_62: |
return 3 * dp_link_count; |
case DP_LINK_BW_2_7: |
return 5 * dp_link_count; |
case DP_LINK_BW_5_4: |
return 10 * dp_link_count; |
} |
return 0; |
} |
|
/** |
* 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; |
} |
|
mgr->pbn_div = drm_dp_get_vc_payload_bw(mgr->dpcd[1], mgr->dpcd[2] & DP_MAX_LANE_COUNT_MASK); |
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); |
|
{ |
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); |
} |
|
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; |
} |
|
|
/* sort out guid */ |
ret = drm_dp_dpcd_read(mgr->aux, DP_GUID, mgr->guid, 16); |
if (ret != 16) { |
DRM_DEBUG_KMS("failed to read DP GUID %d\n", ret); |
goto out_unlock; |
} |
|
mgr->guid_valid = drm_dp_validate_guid(mgr, mgr->guid); |
if (!mgr->guid_valid) { |
ret = drm_dp_dpcd_write(mgr->aux, DP_GUID, mgr->guid, 16); |
mgr->guid_valid = true; |
} |
|
// 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); |
} |
|
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; |
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; |
} |
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; |
bool seqno; |
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, mstb, msg.req_type, seqno, false); |
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, mstb, msg.req_type, seqno, false); |
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 |
* |
* 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_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; |
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; |
|
edid = drm_get_edid(connector, &port->aux.ddc); |
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; |
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); |
|
/** |
* 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) |
{ |
fixed20_12 pix_bw; |
fixed20_12 fbpp; |
fixed20_12 result; |
fixed20_12 margin, tmp; |
u32 res; |
|
pix_bw.full = dfixed_const(clock); |
fbpp.full = dfixed_const(bpp); |
tmp.full = dfixed_const(8); |
fbpp.full = dfixed_div(fbpp, tmp); |
|
result.full = dfixed_mul(pix_bw, fbpp); |
margin.full = dfixed_const(54); |
tmp.full = dfixed_const(64); |
margin.full = dfixed_div(margin, tmp); |
result.full = dfixed_div(result, margin); |
|
margin.full = dfixed_const(1006); |
tmp.full = dfixed_const(1000); |
margin.full = dfixed_div(margin, tmp); |
result.full = dfixed_mul(result, margin); |
|
result.full = dfixed_div(result, tmp); |
result.full = dfixed_ceil(result); |
res = dfixed_trunc(result); |
return res; |
} |
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) |
return -EINVAL; |
ret = drm_dp_calc_pbn_mode(234000, 30); |
if (ret != 1047) |
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); |
} |
|
/** |
* 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); |
INIT_LIST_HEAD(&mgr->tx_msg_upq); |
INIT_LIST_HEAD(&mgr->tx_msg_downq); |
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) { |
DRM_DEBUG_KMS("Unsupported I2C transaction for MST device\n"); |
ret = -EIO; |
goto out; |
} |
|
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); |
} |