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/*
* 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 &drm_connector_funcs.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_cmdline_mode *cmdline_mode;
struct drm_display_mode *mode;
cmdline_mode = &connector->cmdline_mode;
if (!cmdline_mode->specified)
return 0;
/* Only add a GTF mode if we find no matching probed modes */
list_for_each_entry(mode, &connector->probed_modes, head) {
if (mode->hdisplay != cmdline_mode->xres ||
mode->vdisplay != cmdline_mode->yres)
continue;
if (cmdline_mode->refresh_specified) {
/* The probed mode's vrefresh is set until later */
if (drm_mode_vrefresh(mode) != cmdline_mode->refresh)
continue;
}
return 0;
}
mode = drm_mode_create_from_cmdline_mode(connector->dev,
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 - re-enable output polling.
* @dev: drm_device
*
* This function re-enables the output polling work, after it has been
* temporarily disabled using drm_kms_helper_poll_disable(), for example over
* suspend/resume.
*
* 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.
*
* Note that calls to enable and disable polling must be strictly ordered, which
* is automatically the case when they're only call from suspend/resume
* callbacks.
*/
void drm_kms_helper_poll_enable(struct drm_device *dev)
{
bool poll = false;
struct drm_connector *connector;
struct drm_connector_list_iter conn_iter;
unsigned long delay = DRM_OUTPUT_POLL_PERIOD;
if (!dev->mode_config.poll_enabled || !drm_kms_helper_poll)
return;
drm_connector_list_iter_get(dev, &conn_iter);
drm_for_each_connector_iter(connector, &conn_iter) {
if (connector->polled & (DRM_CONNECTOR_POLL_CONNECT |
DRM_CONNECTOR_POLL_DISCONNECT))
poll = true;
}
drm_connector_list_iter_put(&conn_iter);
if (dev->mode_config.delayed_event) {
/*
* FIXME:
*
* Use short (1s) delay to handle the initial delayed event.
* This delay should not be needed, but Optimus/nouveau will
* fail in a mysterious way if the delayed event is handled as
* soon as possible like it is done in
* drm_helper_probe_single_connector_modes() in case the poll
* was enabled before.
*/
poll = true;
delay = HZ;
}
if (poll)
schedule_delayed_work(&dev->mode_config.output_poll_work, delay);
}
EXPORT_SYMBOL(drm_kms_helper_poll_enable);
static enum drm_connector_status
drm_connector_detect(struct drm_connector *connector, bool force)
{
return connector->funcs->detect ?
connector->funcs->detect(connector, force) :
connector_status_connected;
}
/**
* 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
* &drm_connector_funcs.fill_modes() 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())
* - &drm_connector_helper_funcs.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 &drm_connector_helper_funcs.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 = drm_connector_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(dev);
dev->mode_config.poll_running = drm_kms_helper_poll;
if (connector->status
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