linux_dsm_epyc7002/drivers/gpu/drm/i915/i915_utils.c
Lyude Paul 17f5d57915 drm/i915: Force DPCD backlight mode on X1 Extreme 2nd Gen 4K AMOLED panel
The X1 Extreme is one of the systems that lies about which backlight
interface that it uses in its VBIOS as PWM backlight controls don't work
at all on this machine. It's possible that this panel could be one of
the infamous ones that can switch between PWM mode and DPCD backlight
control mode, but we haven't gotten any more details on this from Lenovo
just yet. For the time being though, making sure the backlight 'just
works' is a bit more important.

So, add a quirk to force DPCD backlight controls on for these systems
based on EDID (since this panel doesn't appear to fill in the device ID).
Hopefully in the future we'll figure out a better way of probing this.

Changes since v2:
* The bugzilla URL is deprecated, bug reporting happens on gitlab now.
  Update the messages we print to reflect this
* Also, take the opportunity to move FDO_BUG_URL out of i915_utils.c and
  into i915_utils.h so that other places which print things that aren't
  traditional errors but are worth filing bugs about, can actually use
  it.

Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Adam Jackson <ajax@redhat.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200303215320.93491-1-lyude@redhat.com
2020-03-03 20:34:32 -05:00

106 lines
2.4 KiB
C

// SPDX-License-Identifier: MIT
/*
* Copyright © 2019 Intel Corporation
*/
#include <drm/drm_drv.h>
#include "i915_drv.h"
#include "i915_utils.h"
#define FDO_BUG_MSG "Please file a bug on drm/i915; see " FDO_BUG_URL " for details."
void
__i915_printk(struct drm_i915_private *dev_priv, const char *level,
const char *fmt, ...)
{
static bool shown_bug_once;
struct device *kdev = dev_priv->drm.dev;
bool is_error = level[1] <= KERN_ERR[1];
bool is_debug = level[1] == KERN_DEBUG[1];
struct va_format vaf;
va_list args;
if (is_debug && !drm_debug_enabled(DRM_UT_DRIVER))
return;
va_start(args, fmt);
vaf.fmt = fmt;
vaf.va = &args;
if (is_error)
dev_printk(level, kdev, "%pV", &vaf);
else
dev_printk(level, kdev, "[" DRM_NAME ":%ps] %pV",
__builtin_return_address(0), &vaf);
va_end(args);
if (is_error && !shown_bug_once) {
/*
* Ask the user to file a bug report for the error, except
* if they may have caused the bug by fiddling with unsafe
* module parameters.
*/
if (!test_taint(TAINT_USER))
dev_notice(kdev, "%s", FDO_BUG_MSG);
shown_bug_once = true;
}
}
#if IS_ENABLED(CONFIG_DRM_I915_DEBUG)
static unsigned int i915_probe_fail_count;
int __i915_inject_probe_error(struct drm_i915_private *i915, int err,
const char *func, int line)
{
if (i915_probe_fail_count >= i915_modparams.inject_probe_failure)
return 0;
if (++i915_probe_fail_count < i915_modparams.inject_probe_failure)
return 0;
__i915_printk(i915, KERN_INFO,
"Injecting failure %d at checkpoint %u [%s:%d]\n",
err, i915_modparams.inject_probe_failure, func, line);
i915_modparams.inject_probe_failure = 0;
return err;
}
bool i915_error_injected(void)
{
return i915_probe_fail_count && !i915_modparams.inject_probe_failure;
}
#endif
void cancel_timer(struct timer_list *t)
{
if (!READ_ONCE(t->expires))
return;
del_timer(t);
WRITE_ONCE(t->expires, 0);
}
void set_timer_ms(struct timer_list *t, unsigned long timeout)
{
if (!timeout) {
cancel_timer(t);
return;
}
timeout = msecs_to_jiffies_timeout(timeout);
/*
* Paranoia to make sure the compiler computes the timeout before
* loading 'jiffies' as jiffies is volatile and may be updated in
* the background by a timer tick. All to reduce the complexity
* of the addition and reduce the risk of losing a jiffie.
*/
barrier();
mod_timer(t, jiffies + timeout);
}