/*
* Copyright (c) 2006-2008 Intel Corporation
* Copyright (c) 2007 Dave Airlie <airlied@linux.ie>
*
* DRM core CRTC related functions
*
* 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.
*
* Authors:
* Keith Packard
* Eric Anholt <eric@anholt.net>
* Dave Airlie <airlied@linux.ie>
* Jesse Barnes <jesse.barnes@intel.com>
*/
#include <linux/export.h>
#include <linux/moduleparam.h>
#include <drm/drmP.h>
#include <drm/drm_crtc.h>
#include <drm/drm_fourcc.h>
#include <drm/drm_crtc_helper.h>
#include <drm/drm_fb_helper.h>
#include <drm/drm_edid.h>
/**
* DOC: output probing helper overview
*
* This library provides some helper code for output probing. It provides an
* implementation of the core connector->fill_modes interface with
* drm_helper_probe_single_connector_modes.
*
* It also provides support for polling connectors with a work item and for
* generic hotplug interrupt handling where the driver doesn't or cannot keep
* track of a per-connector hpd interrupt.
*
* This helper library can be used independently of the modeset helper library.
* Drivers can also overwrite different parts e.g. use their own hotplug
* handling code to avoid probing unrelated outputs.
*
* The probe helpers share the function table structures with other display
* helper libraries. See struct &drm_connector_helper_funcs for the details.
*/
static bool drm_kms_helper_poll = true;
module_param_named(poll, drm_kms_helper_poll, bool, 0600);
static enum drm_mode_status
drm_mode_validate_flag(const struct drm_display_mode *mode,
int flags)
{
if ((mode->flags & DRM_MODE_FLAG_INTERLACE) &&
!(flags & DRM_MODE_FLAG_INTERLACE))
return MODE_NO_INTERLACE;
if ((mode->flags & DRM_MODE_FLAG_DBLSCAN) &&
!(flags & DRM_MODE_FLAG_DBLSCAN))
return MODE_NO_DBLESCAN;
if ((mode->flags & DRM_MODE_FLAG_3D_MASK) &&
!(flags & DRM_MODE_FLAG_3D_MASK))
return MODE_NO_STEREO;
return MODE_OK;
}
static int drm_helper_probe_add_cmdline_mode(struct drm_connector *connector)
{
struct drm_display_mode *mode;
if (!connector->cmdline_mode.specified)
return 0;
mode = drm_mode_create_from_cmdline_mode(connector->dev,
&connector->cmdline_mode);
if (mode == NULL)
return 0;
drm_mode_probed_add(connector, mode);
return 1;
}
#define DRM_OUTPUT_POLL_PERIOD (10*HZ)
/**
* drm_kms_helper_poll_enable_locked - re-enable output polling.
* @dev: drm_device
*
* This function re-enables the output polling work without
* locking the mode_config mutex.
*
* This is like drm_kms_helper_poll_enable() however it is to be
* called from a context where the mode_config mutex is locked
* already.
*/
void drm_kms_helper_poll_enable_locked(struct drm_device *dev)
{
bool poll = false;
struct drm_connector *connector;
WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
if (!dev->mode_config.poll_enabled || !drm_kms_helper_poll)
return;
drm_for_each_connector(connector, dev) {
if (connector->polled & (DRM_CONNECTOR_POLL_CONNECT |
DRM_CONNECTOR_POLL_DISCONNECT))
poll = true;
}
if (poll)
schedule_delayed_work(&dev->mode_config.output_poll_work, DRM_OUTPUT_POLL_PERIOD);
}
EXPORT_SYMBOL(drm_kms_helper_poll_enable_locked);
/**
* drm_helper_probe_single_connector_modes - get complete set of display modes
* @connector: connector to probe
* @maxX: max width for modes
* @maxY: max height for modes
*
* Based on the helper callbacks implemented by @connector in struct
* &drm_connector_helper_funcs try to detect all valid modes. Modes will first
* be added to the connector's probed_modes list, then culled (based on validity
* and the @maxX, @maxY parameters) and put into the normal modes list.
*
* Intended to be used as a generic implementation of the ->fill_modes()
* @connector vfunc for drivers that use the CRTC helpers for output mode
* filtering and detection.
*
* The basic procedure is as follows
*
* 1. All modes currently on the connector's modes list are marked as stale
*
* 2. New modes are added to the connector's probed_modes list with
* drm_mode_probed_add(). New modes start their life with status as OK.
* Modes are added from a single source using the following priority order.
*
* - debugfs 'override_edid' (used for testing only)
* - firmware EDID (drm_load_edid_firmware())
* - connector helper ->get_modes() vfunc
* - if the connector status is connector_status_connected, standard
* VESA DMT modes up to 1024x768 are automatically added
* (drm_add_modes_noedid())
*
* Finally modes specified via the kernel command line (video=...) are
* added in addition to what the earlier probes produced
* (drm_helper_probe_add_cmdline_mode()). These modes are generated
* using the VESA GTF/CVT formulas.
*
* 3. Modes are moved from the probed_modes list to the modes list. Potential
* duplicates are merged together (see drm_mode_connector_list_update()).
* After this step the probed_modes list will be empty again.
*
* 4. Any non-stale mode on the modes list then undergoes validation
*
* - drm_mode_validate_basic() performs basic sanity checks
* - drm_mode_validate_size() filters out modes larger than @maxX and @maxY
* (if specified)
* - drm_mode_validate_flag() checks the modes againt basic connector
* capabilites (interlace_allowed,doublescan_allowed,stereo_allowed)
* - the optional connector ->mode_valid() helper can perform driver and/or
* hardware specific checks
*
* 5. Any mode whose status is not OK is pruned from the connector's modes list,
* accompanied by a debug message indicating the reason for the mode's
* rejection (see drm_mode_prune_invalid()).
*
* Returns:
* The number of modes found on @connector.
*/
int drm_helper_probe_single_connector_modes(struct drm_connector *connector,
uint32_t maxX, uint32_t maxY)
{
struct drm_device *dev = connector->dev;
struct drm_display_mode *mode;
const struct drm_connector_helper_funcs *connector_funcs =
connector->helper_private;
int count = 0;
int mode_flags = 0;
bool verbose_prune = true;
enum drm_connector_status old_status;
WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
DRM_DEBUG_KMS("[CONNECTOR:%d:%s]\n", connector->base.id,
connector->name);
/* set all old modes to the stale state */
list_for_each_entry(mode, &connector->modes, head)
mode->status = MODE_STALE;
old_status = connector->status;
if (connector->force) {
if (connector->force == DRM_FORCE_ON ||
connector->force == DRM_FORCE_ON_DIGITAL)
connector->status = connector_status_connected;
else
connector->status = connector_status_disconnected;
if (connector->funcs->force)
connector->funcs->force(connector);
} else {
connector->status = connector->funcs->detect(connector, true);
}
/*
* Normally either the driver's hpd code or the poll loop should
* pick up any changes and fire the hotplug event. But if
* userspace sneaks in a probe, we might miss a change. Hence
* check here, and if anything changed start the hotplug code.
*/
if (old_status != connector->status) {
DRM_DEBUG_KMS("[CONNECTOR:%d:%s] status updated from %s to %s\n",
connector->base.id,
connector->name,
drm_get_connector_status_name(old_status),
drm_get_connector_status_name(connector->status));
/*
* The hotplug event code might call into the fb
* helpers, and so expects that we do not hold any
* locks. Fire up the poll struct instead, it will
* disable itself again.
*/
dev->mode_config.delayed_event = true;
if (dev->mode_config.poll_enabled)
schedule_delayed_work(&dev->mode_config.output_poll_work,
0);
}
/* Re-enable polling in case the global poll config changed. */
if (drm_kms_helper_poll != dev->mode_config.poll_running)
drm_kms_helper_poll_enable_locked(dev);
dev->mode_config.poll_running = drm_kms_helper_poll;
if (connector->status == connector_status_disconnected) {
DRM_DEBUG_KMS("[CONNECTOR:%d:%s] disconnected\n",
connector->base.id, connector->name);
drm_mode_connector_update_edid_property(connector, NULL);
verbose_prune = false;
goto prune;
}
if (connector->override_edid) {
struct edid *edid = (struct edid *) connector->edid_blob_ptr->data;
count = drm_add_edid_modes(connector, edid);
drm_edid_to_eld(connector, edid);
} else {
#ifdef CONFIG_DRM_LOAD_EDID_FIRMWARE
count = drm_load_edid_firmware(connector);
if (count == 0)
#endif
count = (*connector_funcs->get_modes)(connector);
}
if (count == 0 && connector->status == connector_status_connected)
count = drm_add_modes_noedid(connector, 1024, 768);
count += drm_helper_probe_add_cmdline_mode(connector);
if (count == 0)
goto prune;
drm_mode_connector_list_update(connector);
if (connector->interlace_allowed)
mode_flags |= DRM_MODE_FLAG_INTERLACE;
if (connector->doublescan_allowed)
mode_flags |= DRM_MODE_FLAG_DBLSCAN;
if (connector->stereo_allowed)
mode_flags |= DRM_MODE_FLAG_3D_MASK;
list_for_each_entry(mode, &connector->modes, head) {
if (mode->status == MODE_OK)
mode->status = drm_mode_validate_basic(mode);
if (mode->status == MODE_OK)
mode->status = drm_mode_validate_size(mode, maxX, maxY);
if (mode->status == MODE_OK)
mode->status = drm_mode_validate_flag(mode, mode_flags);
if (mode->status == MODE_OK && connector_funcs->mode_valid)
mode->status = connector_funcs->mode_valid(connector,
mode);
}
prune:
drm_mode_prune_invalid(dev, &connector->modes, verbose_prune);
if (list_empty(&connector->modes))
return 0;
list_for_each_entry(mode, &connector->modes, head)
mode->vrefresh = drm_mode_vrefresh(mode);
drm_mode_sort(&connector->modes);
DRM_DEBUG_KMS("[CONNECTOR:%d:%s] probed modes :\n", connector->base.id,
connector->name);
list_for_each_entry(mode, &connector->modes, head) {
drm_mode_set_crtcinfo(mode, CRTC_INTERLACE_HALVE_V);
drm_mode_debug_printmodeline(mode);
}
return count;
}
EXPORT_SYMBOL(drm_helper_probe_single_connector_modes);
/**
* drm_kms_helper_hotplug_event - fire off KMS hotplug events
* @dev: drm_device whose connector state changed
*
* This function fires off the uevent for userspace and also calls the
* output_poll_changed function, which is most commonly used to inform the fbdev
* emulation code and allow it to update the fbcon output configuration.
*
* Drivers should call this from their hotplug handling code when a change is
* detected. Note that this function does not do any output detection of its
* own, like drm_helper_hpd_irq_event() does - this is assumed to be done by the
* driver already.
*
* This function must be called from process context with no mode
* setting locks held.
*/
void drm_kms_helper_hotplug_event(struct drm_device *dev)
{
/* send a uevent + call fbdev */
drm_sysfs_hotplug_event(dev);
if (dev->mode_config.funcs->output_poll_changed)
dev->mode_config.funcs->output_poll_changed(dev);
}
EXPORT_SYMBOL(drm_kms_helper_hotplug_event);
static void output_poll_execute(struct work_struct *work)
{
struct delayed_work *delayed_work = to_delayed_work(work);
struct drm_device *dev = container_of(delayed_work, struct drm_device, mode_config.output_poll_work);
struct drm_connector *connector;
enum drm_connector_status old_status;
bool repoll = false, changed;
/* Pick up any changes detected by the probe functions. */
changed = dev->mode_config.delayed_event;
dev->mode_config.delayed_event = false;
if (!drm_kms_helper_poll)
goto out;
mutex_lock(&dev->mode_config.mutex);
drm_for_each_connector(connector, dev) {
/* Ignore forced connectors. */
if (connector->force)
continue;
/* Ignore HPD capable connectors and connectors where we don't
* want any hotplug detection at all for polling. */
if (!connector->polled || connector->polled == DRM_CONNECTOR_POLL_HPD)
continue;
old_status = connector->status;
/* if we are connected and don't want to poll for disconnect
skip it */
if (old_status == connector_status_connected &&
!(connector->polled & DRM_CONNECTOR_POLL_DISCONNECT))
continue;
repoll = true;
connector->status = connector->funcs->detect(connector, false);
if (old_status != connector->status) {
const char *old, *new;
/*
* The poll work sets force=false when calling detect so
* that drivers can avoid to do disruptive tests (e.g.
* when load detect cycles could cause flickering on
* other, running displays). This bears the risk that we
* flip-flop between unknown here in the poll work and
* the real state when userspace forces a full detect
* call after receiving a hotplug event due to this
* change.
*
* Hence clamp an unknown detect status to the old
* value.
*/
if (connector->status == connector_status_unknown) {
connector->status = old_status;
continue;
}
old = drm_get_connector_status_name(old_status);
new = drm_get_connector_status_name(connector->status);
DRM_DEBUG_KMS("[CONNECTOR:%d:%s] "
"status updated from %s to %s\n",
connector->base.id,
connector->name,
old, new);
changed = true;
}
}
mutex_unlock(&dev->mode_config.mutex);
out:
if (changed)
drm_kms_helper_hotplug_event(dev);
if (repoll)
schedule_delayed_work(delayed_work, DRM_OUTPUT_POLL_PERIOD);
}
/**
* drm_kms_helper_poll_disable - disable output polling
* @dev: drm_device
*
* This function disables the output polling work.
*
* Drivers can call this helper from their device suspend implementation. It is
* not an error to call this even when output polling isn't enabled or arlready
* disabled.
*/
void drm_kms_helper_poll_disable(struct drm_device *dev)
{
if (!dev->mode_config.poll_enabled)
return;
cancel_delayed_work_sync(&dev->mode_config.output_poll_work);
}
EXPORT_SYMBOL(drm_kms_helper_poll_disable);
/**
* drm_kms_helper_poll_enable - re-enable output polling.
* @dev: drm_device
*
* This function re-enables the output polling work.
*
* Drivers can call this helper from their device resume implementation. It is
* an error to call this when the output polling support has not yet been set
* up.
*/
void drm_kms_helper_poll_enable(struct drm_device *dev)
{
mutex_lock(&dev->mode_config.mutex);
drm_kms_helper_poll_enable_locked(dev);
mutex_unlock(&dev->mode_config.mutex);
}
EXPORT_SYMBOL(drm_kms_helper_poll_enable);
/**
* drm_kms_helper_poll_init - initialize and enable output polling
* @dev: drm_device
*
* This function intializes and then also enables output polling support for
* @dev. Drivers which do not have reliable hotplug support in hardware can use
* this helper infrastructure to regularly poll such connectors for changes in
* their connection state.
*
* Drivers can control which connectors are polled by setting the
* DRM_CONNECTOR_POLL_CONNECT and DRM_CONNECTOR_POLL_DISCONNECT flags. On
* connectors where probing live outputs can result in visual distortion drivers
* should not set the DRM_CONNECTOR_POLL_DISCONNECT flag to avoid this.
* Connectors which have no flag or only DRM_CONNECTOR_POLL_HPD set are
* completely ignored by the polling logic.
*
* Note that a connector can be both polled and probed from the hotplug handler,
* in case the hotplug interrupt is known to be unreliable.
*/
void drm_kms_helper_poll_init(struct drm_device *dev)
{
INIT_DELAYED_WORK(&dev->mode_config.output_poll_work, output_poll_execute);
dev->mode_config.poll_enabled = true;
drm_kms_helper_poll_enable(dev);
}
EXPORT_SYMBOL(drm_kms_helper_poll_init);
/**
* drm_kms_helper_poll_fini - disable output polling and clean it up
* @dev: drm_device
*/
void drm_kms_helper_poll_fini(struct drm_device *dev)
{
drm_kms_helper_poll_disable(dev);
}
EXPORT_SYMBOL(drm_kms_helper_poll_fini);
/**
* drm_helper_hpd_irq_event - hotplug processing
* @dev: drm_device
*
* Drivers can use this helper function to run a detect cycle on all connectors
* which have the DRM_CONNECTOR_POLL_HPD flag set in their &polled member. All
* other connectors are ignored, which is useful to avoid reprobing fixed
* panels.
*
* This helper function is useful for drivers which can't or don't track hotplug
* interrupts for each connector.
*
* Drivers which support hotplug interrupts for each connector individually and
* which have a more fine-grained detect logic should bypass this code and
* directly call drm_kms_helper_hotplug_event() in case the connector state
* changed.
*
* This function must be called from process context with no mode
* setting locks held.
*
* Note that a connector can be both polled and probed from the hotplug handler,
* in case the hotplug interrupt is known to be unreliable.
*/
bool drm_helper_hpd_irq_event(struct drm_device *dev)
{
struct drm_connector *connector;
enum drm_connector_status old_status;
bool changed = false;
if (!dev->mode_config.poll_enabled)
return false;
mutex_lock(&dev->mode_config.mutex);
drm_for_each_connector(connector, dev) {
/* Only handle HPD capable connectors. */
if (!(connector->polled & DRM_CONNECTOR_POLL_HPD))
continue;
old_status = connector->status;
connector->status = connector->funcs->detect(connector, false);
DRM_DEBUG_KMS("[CONNECTOR:%d:%s] status updated from %s to %s\n",
connector->base.id,
connector->name,
drm_get_connector_status_name(old_status),
drm_get_connector_status_name(connector->status));
if (old_status != connector->status)
changed = true;
}
mutex_unlock(&dev->mode_config.mutex);
if (changed)
drm_kms_helper_hotplug_event(dev);
return changed;
}
EXPORT_SYMBOL(drm_helper_hpd_irq_event);