[PATCH 4.19 176/205] drm/amdgpu: Suppress keypresses from ACPI_VIDEO events

Greg Kroah-Hartman
2018-11-19T16:38:03Z

From: Lyude Paul <lyude@redhat.com>

commit 582f58de36834096a91cc1de2540c2f7269f850d upstream.

Currently we return NOTIFY_DONE for any event which we don't think is
ours. However, many laptops will send more then just an ATIF event and
will also send an ACPI_VIDEO_NOTIFY_PROBE event as well. Since we don't
check for this, we return NOTIFY_DONE which causes a keypress for the
ACPI event to be propogated to userspace. This is the equivalent of
someone pressing the display key on a laptop every time there's a
hotplug event.

So, check for ACPI_VIDEO_NOTIFY_PROBE events and suppress keypresses
from them.

Signed-off-by: Lyude Paul <lyude@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/gpu/drm/amd/amdgpu/amdgpu_acpi.c | 17 ++++++++++++-----
1 file changed, 12 insertions(+), 5 deletions(-)

--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_acpi.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_acpi.c
@@ -358,7 +358,9 @@ out:
*
* Checks the acpi event and if it matches an atif event,
* handles it.
- * Returns NOTIFY code
+ *
+ * Returns:
+ * NOTIFY_BAD or NOTIFY_DONE, depending on the event.
*/
static int amdgpu_atif_handler(struct amdgpu_device *adev,
struct acpi_bus_event *event)
@@ -372,11 +374,16 @@ static int amdgpu_atif_handler(struct am
if (strcmp(event->device_class, ACPI_VIDEO_CLASS) != 0)
return NOTIFY_DONE;

+ /* Is this actually our event? */
if (!atif ||
!atif->notification_cfg.enabled ||
- event->type != atif->notification_cfg.command_code)
- /* Not our event */
- return NOTIFY_DONE;
+ event->type != atif->notification_cfg.command_code) {
+ /* These events will generate keypresses otherwise */
+ if (event->type == ACPI_VIDEO_NOTIFY_PROBE)
+ return NOTIFY_BAD;
+ else
+ return NOTIFY_DONE;
+ }

if (atif->functions.sbios_requests) {
struct atif_sbios_requests req;
@@ -385,7 +392,7 @@ static int amdgpu_atif_handler(struct am
count = amdgpu_atif_get_sbios_requests(atif, &req);

if (count <= 0)
- return NOTIFY_DONE;
+ return NOTIFY_BAD;

DRM_DEBUG_DRIVER("ATIF: %d pending SBIOS requests\n", count);