Various notebooks with nvidia GPUs generate an ACPI_VIDEO_NOTIFY_PROBE acpi-video event when an external device gets plugged in (and again on modesets on that connector), the default behavior in the acpi-video driver for this is to send a KEY_SWITCHVIDEOMODE evdev event, which causes e.g. gnome-settings-daemon to ask us to rescan the connectors (good), but also causes g-s-d to switch to mirror mode on a newly plugged monitor rather then using the monitor to extend the desktop (bad) as KEY_SWITCHVIDEOMODE is supposed to switch between extend the desktop vs mirror mode.
More troublesome are the repeated ACPI_VIDEO_NOTIFY_PROBE events on changing the mode on the connector, which cause g-s-d to switch between mirror/extend mode, which causes a new ACPI_VIDEO_NOTIFY_PROBE event and we end up with an endless loop. This commit fixes this by adding an acpi notifier block handler to nouveau_display.c to intercept ACPI_VIDEO_NOTIFY_PROBE and: 1) Wake-up runtime suspended GPUs and call drm_helper_hpd_irq_event() on them, this is necessary in some cases for the GPU to detect connector hotplug events while runtime suspended 2) Return NOTIFY_BAD to stop acpi-video from emitting a bogus KEY_SWITCHVIDEOMODE key-press event There already is another acpi notifier block handler registered in drivers/gpu/drm/nouveau/nvkm/engine/device/acpi.c, but that is not suitable since that one gets unregistered on runtime suspend, and we also want to intercept ACPI_VIDEO_NOTIFY_PROBE when runtime suspended. Signed-off-by: Hans de Goede <hdegoede at redhat.com> --- Note that ACPI_VIDEO_NOTIFY_PROBE currently is a private define in drivers/acpi/acpi_video.c, since it is passed to acpi_notifier_call_chain() it really should be in a public header, so I've submitted a patch to the acpi subsys to move it to include/acpi/video.h . In the mean time this patch defines it with a #ifndef guard to allow merging without introducing inter subsys dependencies. I will submit a follow up patch removing the #ifndef block once both patches are in Linus' tree. --- drivers/gpu/drm/nouveau/nouveau_display.c | 61 +++++++++++++++++++++++++++++++ drivers/gpu/drm/nouveau/nouveau_drv.h | 6 +++ 2 files changed, 67 insertions(+) diff --git a/drivers/gpu/drm/nouveau/nouveau_display.c b/drivers/gpu/drm/nouveau/nouveau_display.c index afbf557..6cd6723 100644 --- a/drivers/gpu/drm/nouveau/nouveau_display.c +++ b/drivers/gpu/drm/nouveau/nouveau_display.c @@ -24,6 +24,7 @@ * */ +#include <acpi/video.h> #include <drm/drmP.h> #include <drm/drm_crtc_helper.h> @@ -42,6 +43,8 @@ #include <nvif/cl0046.h> #include <nvif/event.h> + + static int nouveau_display_vblank_handler(struct nvif_notify *notify) { @@ -358,6 +361,55 @@ static struct nouveau_drm_prop_enum_list dither_depth[] = { } \ } while(0) +#ifdef CONFIG_ACPI + +/* + * Hans de Goede: This define belongs in acpi/video.h, I've submitted a patch + * to the acpi subsys to move it there from drivers/acpi/acpi_video.c . + * This should be dropped once that is merged. + */ +#ifndef ACPI_VIDEO_NOTIFY_PROBE +#define ACPI_VIDEO_NOTIFY_PROBE 0x81 +#endif + +static void +nouveau_display_acpi_work(struct work_struct *work) +{ + struct nouveau_drm *drm = container_of(work, typeof(*drm), acpi_work); + + pm_runtime_get_sync(drm->dev->dev); + + drm_helper_hpd_irq_event(drm->dev); + + pm_runtime_mark_last_busy(drm->dev->dev); + pm_runtime_put_sync(drm->dev->dev); +} + +static int +nouveau_display_acpi_ntfy(struct notifier_block *nb, unsigned long val, + void *data) +{ + struct nouveau_drm *drm = container_of(nb, typeof(*drm), acpi_nb); + struct acpi_bus_event *info = data; + + if (!strcmp(info->device_class, ACPI_VIDEO_CLASS)) { + if (info->type == ACPI_VIDEO_NOTIFY_PROBE) { + /* + * This may be the only indication we receive of a + * connector hotplug on a runtime suspended GPU, + * schedule acpi_work to check. + */ + schedule_work(&drm->acpi_work); + + /* acpi-video should not generate keypresses for this */ + return NOTIFY_BAD; + } + } + + return NOTIFY_DONE; +} +#endif + int nouveau_display_init(struct drm_device *dev) { @@ -537,6 +589,12 @@ nouveau_display_create(struct drm_device *dev) } nouveau_backlight_init(dev); +#ifdef CONFIG_ACPI + INIT_WORK(&drm->acpi_work, nouveau_display_acpi_work); + drm->acpi_nb.notifier_call = nouveau_display_acpi_ntfy; + register_acpi_notifier(&drm->acpi_nb); +#endif + return 0; vblank_err: @@ -552,6 +610,9 @@ nouveau_display_destroy(struct drm_device *dev) { struct nouveau_display *disp = nouveau_display(dev); +#ifdef CONFIG_ACPI + unregister_acpi_notifier(&nouveau_drm(dev)->acpi_nb); +#endif nouveau_backlight_exit(dev); nouveau_display_vblank_fini(dev); diff --git a/drivers/gpu/drm/nouveau/nouveau_drv.h b/drivers/gpu/drm/nouveau/nouveau_drv.h index 822a021..71d4532 100644 --- a/drivers/gpu/drm/nouveau/nouveau_drv.h +++ b/drivers/gpu/drm/nouveau/nouveau_drv.h @@ -37,6 +37,8 @@ * - implemented limited ABI16/NVIF interop */ +#include <linux/notifier.h> + #include <nvif/client.h> #include <nvif/device.h> #include <nvif/ioctl.h> @@ -161,6 +163,10 @@ struct nouveau_drm { struct nvbios vbios; struct nouveau_display *display; struct backlight_device *backlight; +#ifdef CONFIG_ACPI + struct notifier_block acpi_nb; + struct work_struct acpi_work; +#endif /* power management */ struct nouveau_hwmon *hwmon; -- 2.9.3