drm/radeon/atif: Send a hotplug event when we get dgpu display request

On PX systems, if the platform supports hotplug events ATIF while the
dGPU is powered down, handle the event and alert userspace.

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/radeon/radeon_acpi.c b/drivers/gpu/drm/radeon/radeon_acpi.c
index 31c9a92d6a1b89da90863e761fa4701f15d3ad3f..6efbd65c929efc28135056c4077ed979e18017c3 100644 (file)
--- a/drivers/gpu/drm/radeon/radeon_acpi.c
+++ b/drivers/gpu/drm/radeon/radeon_acpi.c
@@ -25,6 +25,7 @@
 #include <linux/acpi.h>
 #include <linux/slab.h>
 #include <linux/power_supply.h>
+#include <linux/pm_runtime.h>
 #include <acpi/video.h>
 #include <drm/drmP.h>
 #include <drm/drm_crtc_helper.h>
@@ -32,6 +33,12 @@
 #include "radeon_acpi.h"
 #include "atom.h"
 
+#if defined(CONFIG_VGA_SWITCHEROO)
+bool radeon_atpx_dgpu_req_power_for_displays(void);
+#else
+static inline bool radeon_atpx_dgpu_req_power_for_displays(void) { return false; }
+#endif
+
 #define ACPI_AC_CLASS           "ac_adapter"
 
 extern void radeon_pm_acpi_event_handler(struct radeon_device *rdev);
@@ -394,6 +401,16 @@ int radeon_atif_handler(struct radeon_device *rdev,
 #endif
                }
        }
+       if (req.pending & ATIF_DGPU_DISPLAY_EVENT) {
+               if ((rdev->flags & RADEON_IS_PX) &&
+                   radeon_atpx_dgpu_req_power_for_displays()) {
+                       pm_runtime_get_sync(rdev->ddev->dev);
+                       /* Just fire off a uevent and let userspace tell us what to do */
+                       drm_helper_hpd_irq_event(rdev->ddev);
+                       pm_runtime_mark_last_busy(rdev->ddev->dev);
+                       pm_runtime_put_autosuspend(rdev->ddev->dev);
+               }
+       }
        /* TODO: check other events */
 
        /* We've handled the event, stop the notifier chain. The ACPI interface