[mirror_ubuntu-bionic-kernel.git] / drivers / gpu / drm / drm_probe_helper.c

/*
 * 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.
 */

static bool drm_kms_helper_poll = true;
module_param_named(poll, drm_kms_helper_poll, bool, 0600);

static void drm_mode_validate_flag(struct drm_connector *connector,
				   int flags)
{
	struct drm_display_mode *mode;

	if (flags == (DRM_MODE_FLAG_DBLSCAN | DRM_MODE_FLAG_INTERLACE |
		      DRM_MODE_FLAG_3D_MASK))
		return;

	list_for_each_entry(mode, &connector->modes, head) {
		if ((mode->flags & DRM_MODE_FLAG_INTERLACE) &&
				!(flags & DRM_MODE_FLAG_INTERLACE))
			mode->status = MODE_NO_INTERLACE;
		if ((mode->flags & DRM_MODE_FLAG_DBLSCAN) &&
				!(flags & DRM_MODE_FLAG_DBLSCAN))
			mode->status = MODE_NO_DBLESCAN;
		if ((mode->flags & DRM_MODE_FLAG_3D_MASK) &&
				!(flags & DRM_MODE_FLAG_3D_MASK))
			mode->status = MODE_NO_STEREO;
	}

	return;
}

static int drm_helper_probe_single_connector_modes_merge_bits(struct drm_connector *connector,
							      uint32_t maxX, uint32_t maxY, bool merge_type_bits)
{
	struct drm_device *dev = connector->dev;
	struct drm_display_mode *mode;
	struct drm_connector_helper_funcs *connector_funcs =
		connector->helper_private;
	int count = 0;
	int mode_flags = 0;
	bool verbose_prune = true;

	WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));

	DRM_DEBUG_KMS("[CONNECTOR:%d:%s]\n", connector->base.id,
			connector->name);
	/* set all modes to the unverified state */
	list_for_each_entry(mode, &connector->modes, head)
		mode->status = MODE_UNVERIFIED;

	if (connector->force) {
		if (connector->force == DRM_FORCE_ON)
			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);
	}

	/* 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(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;
	}

#ifdef CONFIG_DRM_LOAD_EDID_FIRMWARE
	count = drm_load_edid_firmware(connector);
	if (count == 0)
#endif
	{
		if (connector->override_edid) {
			struct edid *edid = (struct edid *) connector->edid_blob_ptr->data;

			count = drm_add_edid_modes(connector, edid);
		} else
			count = (*connector_funcs->get_modes)(connector);
	}

	if (count == 0 && connector->status == connector_status_connected)
		count = drm_add_modes_noedid(connector, 1024, 768);
	if (count == 0)
		goto prune;

	drm_mode_connector_list_update(connector, merge_type_bits);

	if (maxX && maxY)
		drm_mode_validate_size(dev, &connector->modes, maxX, maxY);

	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;
	drm_mode_validate_flag(connector, mode_flags);

	list_for_each_entry(mode, &connector->modes, head) {
		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;
}

/**
 * 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 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 use as a generic implementation of the ->fill_modes()
 * @connector vfunc for drivers that use the crtc helpers for output mode
 * filtering and detection.
 *
 * 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)
{
	return drm_helper_probe_single_connector_modes_merge_bits(connector, maxX, maxY, true);
}
EXPORT_SYMBOL(drm_helper_probe_single_connector_modes);

/**
 * drm_helper_probe_single_connector_modes_nomerge - get complete set of display modes
 * @connector: connector to probe
 * @maxX: max width for modes
 * @maxY: max height for modes
 *
 * This operates like drm_hehlper_probe_single_connector_modes except it
 * replaces the mode bits instead of merging them for preferred modes.
 */
int drm_helper_probe_single_connector_modes_nomerge(struct drm_connector *connector,
					    uint32_t maxX, uint32_t maxY)
{
	return drm_helper_probe_single_connector_modes_merge_bits(connector, maxX, maxY, false);
}
EXPORT_SYMBOL(drm_helper_probe_single_connector_modes_nomerge);

/**
 * 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);

#define DRM_OUTPUT_POLL_PERIOD (10*HZ)
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 = false;

	if (!drm_kms_helper_poll)
		return;

	mutex_lock(&dev->mode_config.mutex);
	list_for_each_entry(connector, &dev->mode_config.connector_list, head) {

		/* 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;

		repoll = true;

		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;

		connector->status = connector->funcs->detect(connector, false);
		if (old_status != connector->status) {
			const char *old, *new;

			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);

	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)
{
	bool poll = false;
	struct drm_connector *connector;

	if (!dev->mode_config.poll_enabled || !drm_kms_helper_poll)
		return;

	list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
		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);

/**
 * 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);
	list_for_each_entry(connector, &dev->mode_config.connector_list, head) {

		/* 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);
Commit	Line	Data
8d754544 DV	1	/*
	2	* Copyright (c) 2006-2008 Intel Corporation
	3	* Copyright (c) 2007 Dave Airlie <airlied@linux.ie>
	4	*
	5	* DRM core CRTC related functions
	6	*
	7	* Permission to use, copy, modify, distribute, and sell this software and its
	8	* documentation for any purpose is hereby granted without fee, provided that
	9	* the above copyright notice appear in all copies and that both that copyright
	10	* notice and this permission notice appear in supporting documentation, and
	11	* that the name of the copyright holders not be used in advertising or
	12	* publicity pertaining to distribution of the software without specific,
	13	* written prior permission. The copyright holders make no representations
	14	* about the suitability of this software for any purpose. It is provided "as
	15	* is" without express or implied warranty.
	16	*
	17	* THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
	18	* INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
	19	* EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
	20	* CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
	21	* DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
	22	* TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
	23	* OF THIS SOFTWARE.
	24	*
	25	* Authors:
	26	* Keith Packard
	27	* Eric Anholt <eric@anholt.net>
	28	* Dave Airlie <airlied@linux.ie>
	29	* Jesse Barnes <jesse.barnes@intel.com>
	30	*/
	31
	32	#include <linux/export.h>
	33	#include <linux/moduleparam.h>
	34
	35	#include <drm/drmP.h>
	36	#include <drm/drm_crtc.h>
	37	#include <drm/drm_fourcc.h>
	38	#include <drm/drm_crtc_helper.h>
	39	#include <drm/drm_fb_helper.h>
	40	#include <drm/drm_edid.h>
	41
	42	/**
	43	* DOC: output probing helper overview
	44	*
	45	* This library provides some helper code for output probing. It provides an
	46	* implementation of the core connector->fill_modes interface with
	47	* drm_helper_probe_single_connector_modes.
	48	*
	49	* It also provides support for polling connectors with a work item and for
	50	* generic hotplug interrupt handling where the driver doesn't or cannot keep
	51	* track of a per-connector hpd interrupt.
	52	*
	53	* This helper library can be used independently of the modeset helper library.
	54	* Drivers can also overwrite different parts e.g. use their own hotplug
	55	* handling code to avoid probing unrelated outputs.
	56	*/
	57
	58	static bool drm_kms_helper_poll = true;
	59	module_param_named(poll, drm_kms_helper_poll, bool, 0600);
	60
	61	static void drm_mode_validate_flag(struct drm_connector *connector,
	62	int flags)
	63	{
	64	struct drm_display_mode *mode;
65
66	if (flags == (DRM_MODE_FLAG_DBLSCAN \| DRM_MODE_FLAG_INTERLACE \|
67	DRM_MODE_FLAG_3D_MASK))
68	return;
69
70	list_for_each_entry(mode, &connector->modes, head) {
71	if ((mode->flags & DRM_MODE_FLAG_INTERLACE) &&
72	!(flags & DRM_MODE_FLAG_INTERLACE))
73	mode->status = MODE_NO_INTERLACE;
74	if ((mode->flags & DRM_MODE_FLAG_DBLSCAN) &&
75	!(flags & DRM_MODE_FLAG_DBLSCAN))
76	mode->status = MODE_NO_DBLESCAN;
77	if ((mode->flags & DRM_MODE_FLAG_3D_MASK) &&
78	!(flags & DRM_MODE_FLAG_3D_MASK))
79	mode->status = MODE_NO_STEREO;
80	}
81
82	return;
83	}
84
b87577b7 DA	85	static int drm_helper_probe_single_connector_modes_merge_bits(struct drm_connector *connector,
b87577b7 DA	86	uint32_t maxX, uint32_t maxY, bool merge_type_bits)
8d754544 DV	87	{
	88	struct drm_device *dev = connector->dev;
	89	struct drm_display_mode *mode;
	90	struct drm_connector_helper_funcs *connector_funcs =
	91	connector->helper_private;
	92	int count = 0;
	93	int mode_flags = 0;
	94	bool verbose_prune = true;
	95
	96	WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
	97
	98	DRM_DEBUG_KMS("[CONNECTOR:%d:%s]\n", connector->base.id,
25933820	99	connector->name);
8d754544 DV	100	/* set all modes to the unverified state */
	101	list_for_each_entry(mode, &connector->modes, head)
	102	mode->status = MODE_UNVERIFIED;
	103
	104	if (connector->force) {
	105	if (connector->force == DRM_FORCE_ON)
	106	connector->status = connector_status_connected;
	107	else
	108	connector->status = connector_status_disconnected;
	109	if (connector->funcs->force)
	110	connector->funcs->force(connector);
	111	} else {
	112	connector->status = connector->funcs->detect(connector, true);
	113	}
	114
	115	/* Re-enable polling in case the global poll config changed. */
	116	if (drm_kms_helper_poll != dev->mode_config.poll_running)
	117	drm_kms_helper_poll_enable(dev);
	118
	119	dev->mode_config.poll_running = drm_kms_helper_poll;
	120
	121	if (connector->status == connector_status_disconnected) {
	122	DRM_DEBUG_KMS("[CONNECTOR:%d:%s] disconnected\n",
25933820	123	connector->base.id, connector->name);
8d754544 DV	124	drm_mode_connector_update_edid_property(connector, NULL);
	125	verbose_prune = false;
	126	goto prune;
	127	}
	128
	129	#ifdef CONFIG_DRM_LOAD_EDID_FIRMWARE
	130	count = drm_load_edid_firmware(connector);
	131	if (count == 0)
	132	#endif
4cf2b281 TW	133	{
	134	if (connector->override_edid) {
	135	struct edid edid = (struct edid ) connector->edid_blob_ptr->data;
	136
	137	count = drm_add_edid_modes(connector, edid);
	138	} else
	139	count = (*connector_funcs->get_modes)(connector);
	140	}
8d754544 DV	141
	142	if (count == 0 && connector->status == connector_status_connected)
	143	count = drm_add_modes_noedid(connector, 1024, 768);
	144	if (count == 0)
	145	goto prune;
	146
b87577b7	147	drm_mode_connector_list_update(connector, merge_type_bits);
8d754544 DV	148
	149	if (maxX && maxY)
	150	drm_mode_validate_size(dev, &connector->modes, maxX, maxY);
	151
	152	if (connector->interlace_allowed)
	153	mode_flags \|= DRM_MODE_FLAG_INTERLACE;
	154	if (connector->doublescan_allowed)
	155	mode_flags \|= DRM_MODE_FLAG_DBLSCAN;
	156	if (connector->stereo_allowed)
	157	mode_flags \|= DRM_MODE_FLAG_3D_MASK;
	158	drm_mode_validate_flag(connector, mode_flags);
	159
	160	list_for_each_entry(mode, &connector->modes, head) {
f9b0e251	161	if (mode->status == MODE_OK && connector_funcs->mode_valid)
8d754544 DV	162	mode->status = connector_funcs->mode_valid(connector,
	163	mode);
	164	}
	165
	166	prune:
	167	drm_mode_prune_invalid(dev, &connector->modes, verbose_prune);
	168
	169	if (list_empty(&connector->modes))
	170	return 0;
	171
	172	list_for_each_entry(mode, &connector->modes, head)
	173	mode->vrefresh = drm_mode_vrefresh(mode);
	174
	175	drm_mode_sort(&connector->modes);
	176
	177	DRM_DEBUG_KMS("[CONNECTOR:%d:%s] probed modes :\n", connector->base.id,
25933820	178	connector->name);
8d754544 DV	179	list_for_each_entry(mode, &connector->modes, head) {
	180	drm_mode_set_crtcinfo(mode, CRTC_INTERLACE_HALVE_V);
	181	drm_mode_debug_printmodeline(mode);
	182	}
	183
	184	return count;
	185	}
b87577b7 DA	186
	187	/**
	188	* drm_helper_probe_single_connector_modes - get complete set of display modes
	189	* @connector: connector to probe
	190	* @maxX: max width for modes
	191	* @maxY: max height for modes
	192	*
	193	* Based on the helper callbacks implemented by @connector try to detect all
	194	* valid modes. Modes will first be added to the connector's probed_modes list,
	195	* then culled (based on validity and the @maxX, @maxY parameters) and put into
	196	* the normal modes list.
	197	*
	198	* Intended to be use as a generic implementation of the ->fill_modes()
	199	* @connector vfunc for drivers that use the crtc helpers for output mode
	200	* filtering and detection.
	201	*
	202	* Returns:
	203	* The number of modes found on @connector.
	204	*/
	205	int drm_helper_probe_single_connector_modes(struct drm_connector *connector,
	206	uint32_t maxX, uint32_t maxY)
	207	{
	208	return drm_helper_probe_single_connector_modes_merge_bits(connector, maxX, maxY, true);
	209	}
8d754544 DV	210	EXPORT_SYMBOL(drm_helper_probe_single_connector_modes);
8d754544 DV	211
b87577b7 DA	212	/**
	213	* drm_helper_probe_single_connector_modes_nomerge - get complete set of display modes
	214	* @connector: connector to probe
	215	* @maxX: max width for modes
	216	* @maxY: max height for modes
	217	*
	218	* This operates like drm_hehlper_probe_single_connector_modes except it
	219	* replaces the mode bits instead of merging them for preferred modes.
	220	*/
	221	int drm_helper_probe_single_connector_modes_nomerge(struct drm_connector *connector,
	222	uint32_t maxX, uint32_t maxY)
	223	{
	224	return drm_helper_probe_single_connector_modes_merge_bits(connector, maxX, maxY, false);
	225	}
	226	EXPORT_SYMBOL(drm_helper_probe_single_connector_modes_nomerge);
	227
8d754544 DV	228	/**
	229	* drm_kms_helper_hotplug_event - fire off KMS hotplug events
	230	* @dev: drm_device whose connector state changed
	231	*
	232	* This function fires off the uevent for userspace and also calls the
	233	* output_poll_changed function, which is most commonly used to inform the fbdev
	234	* emulation code and allow it to update the fbcon output configuration.
	235	*
	236	* Drivers should call this from their hotplug handling code when a change is
	237	* detected. Note that this function does not do any output detection of its
	238	* own, like drm_helper_hpd_irq_event() does - this is assumed to be done by the
	239	* driver already.
	240	*
	241	* This function must be called from process context with no mode
	242	* setting locks held.
	243	*/
	244	void drm_kms_helper_hotplug_event(struct drm_device *dev)
	245	{
	246	/* send a uevent + call fbdev */
	247	drm_sysfs_hotplug_event(dev);
	248	if (dev->mode_config.funcs->output_poll_changed)
	249	dev->mode_config.funcs->output_poll_changed(dev);
	250	}
	251	EXPORT_SYMBOL(drm_kms_helper_hotplug_event);
	252
	253	#define DRM_OUTPUT_POLL_PERIOD (10*HZ)
	254	static void output_poll_execute(struct work_struct *work)
	255	{
	256	struct delayed_work *delayed_work = to_delayed_work(work);
	257	struct drm_device *dev = container_of(delayed_work, struct drm_device, mode_config.output_poll_work);
	258	struct drm_connector *connector;
	259	enum drm_connector_status old_status;
	260	bool repoll = false, changed = false;
	261
	262	if (!drm_kms_helper_poll)
	263	return;
	264
	265	mutex_lock(&dev->mode_config.mutex);
	266	list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
	267
	268	/* Ignore forced connectors. */
	269	if (connector->force)
	270	continue;
	271
	272	/* Ignore HPD capable connectors and connectors where we don't
	273	* want any hotplug detection at all for polling. */
	274	if (!connector->polled \|\| connector->polled == DRM_CONNECTOR_POLL_HPD)
	275	continue;
	276
	277	repoll = true;
	278
	279	old_status = connector->status;
	280	/* if we are connected and don't want to poll for disconnect
	281	skip it */
	282	if (old_status == connector_status_connected &&
	283	!(connector->polled & DRM_CONNECTOR_POLL_DISCONNECT))
	284	continue;
	285
	286	connector->status = connector->funcs->detect(connector, false);
	287	if (old_status != connector->status) {
	288	const char old, new;
	289
	290	old = drm_get_connector_status_name(old_status);
	291	new = drm_get_connector_status_name(connector->status);
292
293	DRM_DEBUG_KMS("[CONNECTOR:%d:%s] "
294	"status updated from %s to %s\n",
295	connector->base.id,
25933820	296	connector->name,
8d754544 DV	297	old, new);
	298
	299	changed = true;
	300	}
	301	}
	302
	303	mutex_unlock(&dev->mode_config.mutex);
	304
	305	if (changed)
	306	drm_kms_helper_hotplug_event(dev);
	307
	308	if (repoll)
	309	schedule_delayed_work(delayed_work, DRM_OUTPUT_POLL_PERIOD);
	310	}
	311
	312	/**
	313	* drm_kms_helper_poll_disable - disable output polling
	314	* @dev: drm_device
	315	*
	316	* This function disables the output polling work.
	317	*
	318	* Drivers can call this helper from their device suspend implementation. It is
	319	* not an error to call this even when output polling isn't enabled or arlready
	320	* disabled.
	321	*/
	322	void drm_kms_helper_poll_disable(struct drm_device *dev)
	323	{
	324	if (!dev->mode_config.poll_enabled)
	325	return;
	326	cancel_delayed_work_sync(&dev->mode_config.output_poll_work);
	327	}
	328	EXPORT_SYMBOL(drm_kms_helper_poll_disable);
	329
	330	/**
	331	* drm_kms_helper_poll_enable - re-enable output polling.
	332	* @dev: drm_device
	333	*
	334	* This function re-enables the output polling work.
	335	*
	336	* Drivers can call this helper from their device resume implementation. It is
	337	* an error to call this when the output polling support has not yet been set
	338	* up.
	339	*/
	340	void drm_kms_helper_poll_enable(struct drm_device *dev)
	341	{
	342	bool poll = false;
	343	struct drm_connector *connector;
	344
	345	if (!dev->mode_config.poll_enabled \|\| !drm_kms_helper_poll)
	346	return;
	347
	348	list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
	349	if (connector->polled & (DRM_CONNECTOR_POLL_CONNECT \|
	350	DRM_CONNECTOR_POLL_DISCONNECT))
	351	poll = true;
	352	}
	353
	354	if (poll)
	355	schedule_delayed_work(&dev->mode_config.output_poll_work, DRM_OUTPUT_POLL_PERIOD);
	356	}
	357	EXPORT_SYMBOL(drm_kms_helper_poll_enable);
	358
	359	/**
	360	* drm_kms_helper_poll_init - initialize and enable output polling
361	* @dev: drm_device
362	*
363	* This function intializes and then also enables output polling support for
364	* @dev. Drivers which do not have reliable hotplug support in hardware can use
365	* this helper infrastructure to regularly poll such connectors for changes in
366	* their connection state.
367	*
368	* Drivers can control which connectors are polled by setting the
369	* DRM_CONNECTOR_POLL_CONNECT and DRM_CONNECTOR_POLL_DISCONNECT flags. On
370	* connectors where probing live outputs can result in visual distortion drivers
371	* should not set the DRM_CONNECTOR_POLL_DISCONNECT flag to avoid this.
372	* Connectors which have no flag or only DRM_CONNECTOR_POLL_HPD set are
373	* completely ignored by the polling logic.
374	*
375	* Note that a connector can be both polled and probed from the hotplug handler,
376	* in case the hotplug interrupt is known to be unreliable.
377	*/
378	void drm_kms_helper_poll_init(struct drm_device *dev)
379	{
380	INIT_DELAYED_WORK(&dev->mode_config.output_poll_work, output_poll_execute);
381	dev->mode_config.poll_enabled = true;
382
383	drm_kms_helper_poll_enable(dev);
384	}
385	EXPORT_SYMBOL(drm_kms_helper_poll_init);
386
387	/**
388	* drm_kms_helper_poll_fini - disable output polling and clean it up
389	* @dev: drm_device
390	*/
391	void drm_kms_helper_poll_fini(struct drm_device *dev)
392	{
393	drm_kms_helper_poll_disable(dev);
394	}
395	EXPORT_SYMBOL(drm_kms_helper_poll_fini);
396
397	/**
398	* drm_helper_hpd_irq_event - hotplug processing
399	* @dev: drm_device
400	*
401	* Drivers can use this helper function to run a detect cycle on all connectors
402	* which have the DRM_CONNECTOR_POLL_HPD flag set in their &polled member. All
403	* other connectors are ignored, which is useful to avoid reprobing fixed
404	* panels.
405	*
406	* This helper function is useful for drivers which can't or don't track hotplug
407	* interrupts for each connector.
408	*
409	* Drivers which support hotplug interrupts for each connector individually and
410	* which have a more fine-grained detect logic should bypass this code and
411	* directly call drm_kms_helper_hotplug_event() in case the connector state
412	* changed.
413	*
414	* This function must be called from process context with no mode
415	* setting locks held.
416	*
417	* Note that a connector can be both polled and probed from the hotplug handler,
418	* in case the hotplug interrupt is known to be unreliable.
419	*/
420	bool drm_helper_hpd_irq_event(struct drm_device *dev)
421	{
422	struct drm_connector *connector;
423	enum drm_connector_status old_status;
424	bool changed = false;
425
426	if (!dev->mode_config.poll_enabled)
427	return false;
428
429	mutex_lock(&dev->mode_config.mutex);
430	list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
431
432	/* Only handle HPD capable connectors. */
433	if (!(connector->polled & DRM_CONNECTOR_POLL_HPD))
434	continue;
435
436	old_status = connector->status;
437
438	connector->status = connector->funcs->detect(connector, false);
439	DRM_DEBUG_KMS("[CONNECTOR:%d:%s] status updated from %s to %s\n",
440	connector->base.id,
25933820	441	connector->name,
8d754544 DV	442	drm_get_connector_status_name(old_status),
	443	drm_get_connector_status_name(connector->status));
	444	if (old_status != connector->status)
	445	changed = true;
	446	}
	447
	448	mutex_unlock(&dev->mode_config.mutex);
	449
	450	if (changed)
	451	drm_kms_helper_hotplug_event(dev);
	452
	453	return changed;
	454	}
	455	EXPORT_SYMBOL(drm_helper_hpd_irq_event);