Validate FD when reporting brightness support.

If we fail to open the brightness sysfs node, then we shouldn't report
that we support setting the brightness since any attempts fail.

Also, fix capabilities count. This was accidentally left in when moving
brightness support from a global capability to a display-specific one.

Bug: 128496688
Test: manual
Change-Id: Ie623b98232481bca3c0f955b259a3b168c83cf2e

1 files changed, 16 insertions, 5 deletions

diff --git a/sdm/libs/hwc2/hwc_session.cpp b/sdm/libs/hwc2/hwc_session.cpp
index 60b719f8..3b13681b 100644
--- a/sdm/libs/hwc2/hwc_session.cpp
+++ b/sdm/libs/hwc2/hwc_session.cpp
@@ -310,7 +310,7 @@ void HWCSession::GetCapabilities(struct hwc2_device *device, uint32_t *outCount,
   if (Debug::Get()->GetProperty(DISABLE_SKIP_VALIDATE_PROP, &value) == kErrorNone) {
     disable_skip_validate = (value == 1);
   }
-  uint32_t count = 2 + (disable_skip_validate ? 0 : 1);
+  uint32_t count = 1 + (disable_skip_validate ? 0 : 1);
 
   if (outCapabilities != nullptr && (*outCount >= count)) {
     outCapabilities[0] = HWC2_CAPABILITY_SKIP_CLIENT_COLOR_TRANSFORM;
@@ -948,9 +948,14 @@ int32_t HWCSession::GetDisplayCapabilities(hwc2_device_t* device, hwc2_display_t
     return INT32(HWC2::Error::None);
   }
 
-  bool brightness_support = display == HWC_DISPLAY_PRIMARY;
+  bool brightness_support = false;
+  auto status = GetDisplayBrightnessSupport(device, display, &brightness_support);
+  if (status != HWC2_ERROR_NONE) {
+    DLOGE("Failed to get display brightness support Error = %d", status);
+    return INT32(status);
+  }
   int doze_support = 0;
-  auto status = GetDozeSupport(device, display, &doze_support);
+  status = GetDozeSupport(device, display, &doze_support);
   if (status != HWC2_ERROR_NONE) {
     DLOGE("Failed to get doze support Error = %d", status);
     return INT32(status);
@@ -974,13 +979,19 @@ int32_t HWCSession::GetDisplayCapabilities(hwc2_device_t* device, hwc2_display_t
 
 int32_t HWCSession::GetDisplayBrightnessSupport(hwc2_device_t *device, hwc2_display_t display,
                                                 bool *out_support) {
-  *out_support = display == HWC_DISPLAY_PRIMARY;
+  HWCSession *hwc_session = static_cast<HWCSession *>(device);
+  *out_support = display == HWC_DISPLAY_PRIMARY && hwc_session->brightness_fd_ != -1;
   return INT32(HWC2::Error::None);
 }
 
 int32_t HWCSession::SetDisplayBrightness(hwc2_device_t *device, hwc2_display_t display,
                                          float brightness) {
-  if (display != HWC_DISPLAY_PRIMARY) {
+  bool brightness_support = false;
+  auto status = GetDisplayBrightnessSupport(device, display, &brightness_support);
+  if (status != HWC2_ERROR_NONE) {
+    return INT32(status);
+  }
+  if (!brightness_support) {
     return INT32(HWC2::Error::BadDisplay);
   }
   int backlight = -1;