hal: adding support for DRC on WiFi display
When Dynamic Resolution Change (DRC) is triggered in the WiFi display
stack, it results in a PAUSE and a RESUME event. During DRC, the
dimensions of the framebuffer are changed. To support DRC we need to:
1. Check if a RESUME event is the result of a valid DRC event
2. Reconfigure the display's attributes to reflect resolution change
3. Enable MDP downscaling when necessary (Valid DRC cases)
Change-Id: Idc3cbc94de99a4a7299e2f6b26c3e35937c1d6c8
diff --git a/libhwcomposer/hwc_uevents.cpp b/libhwcomposer/hwc_uevents.cpp
index 5590798..cc5b482 100644
--- a/libhwcomposer/hwc_uevents.cpp
+++ b/libhwcomposer/hwc_uevents.cpp
@@ -273,6 +273,15 @@
//its pipes; we don't allow inter-mixer pipe transfers.
{
Locker::Autolock _l(ctx->mDrawLock);
+
+ // A dynamic resolution change (DRC) can be made for a WiFi
+ // display. In order to support the resolution change, we
+ // need to reconfigure the corresponding display attributes.
+ // Since DRC is only on WiFi display, we only need to call
+ // configure() on the VirtualDisplay device.
+ if(dpy == HWC_DISPLAY_VIRTUAL)
+ ctx->mVirtualDisplay->configure();
+
ctx->dpyAttr[dpy].isConfiguring = true;
ctx->dpyAttr[dpy].isActive = true;
ctx->proc->invalidate(ctx->proc);
diff --git a/libvirtual/virtual.cpp b/libvirtual/virtual.cpp
index 8e96a56..c94a5c6 100644
--- a/libvirtual/virtual.cpp
+++ b/libvirtual/virtual.cpp
@@ -76,6 +76,10 @@
int VirtualDisplay::teardown() {
closeFrameBuffer();
memset(&mVInfo, 0, sizeof(mVInfo));
+ // Reset the resolution when we close the fb for this device. We need
+ // this to distinguish between an ONLINE and RESUME event.
+ mHwcContext->dpyAttr[HWC_DISPLAY_VIRTUAL].xres = 0;
+ mHwcContext->dpyAttr[HWC_DISPLAY_VIRTUAL].yres = 0;
return 0;
}
@@ -92,24 +96,41 @@
void VirtualDisplay::setAttributes() {
if(mHwcContext) {
- // Always set dpyAttr res to mVInfo res
- mHwcContext->dpyAttr[HWC_DISPLAY_VIRTUAL].xres = mVInfo.xres;
- mHwcContext->dpyAttr[HWC_DISPLAY_VIRTUAL].yres = mVInfo.yres;
+ unsigned int &w = mHwcContext->dpyAttr[HWC_DISPLAY_VIRTUAL].xres;
+ unsigned int &h = mHwcContext->dpyAttr[HWC_DISPLAY_VIRTUAL].yres;
+
+ // Always set dpyAttr res to mVInfo res, only on an ONLINE event. Keep
+ // the original configuration to cater for DRC initiated RESUME events
+ if(w == 0 || h == 0){
+ w = mVInfo.xres;
+ h = mVInfo.yres;
+ }
mHwcContext->dpyAttr[HWC_DISPLAY_VIRTUAL].mDownScaleMode = false;
+
if(!qdutils::MDPVersion::getInstance().is8x26()) {
uint32_t priW = mHwcContext->dpyAttr[HWC_DISPLAY_PRIMARY].xres;
uint32_t priH = mHwcContext->dpyAttr[HWC_DISPLAY_PRIMARY].yres;
- // if primary resolution is more than the wfd resolution
+
+ // Find the maximum resolution between primary and virtual
+ uint32_t maxArea = max((w * h), (priW * priH));
+
+ // If primary resolution is more than the wfd resolution
// configure dpy attr to primary resolution and set
- // downscale mode
- if((priW * priH) > (mVInfo.xres * mVInfo.yres)) {
- mHwcContext->dpyAttr[HWC_DISPLAY_VIRTUAL].xres = priW;
- mHwcContext->dpyAttr[HWC_DISPLAY_VIRTUAL].yres = priH;
- // WFD is always in landscape, so always assign the higher
- // dimension to wfd's xres
- if(priH > priW) {
- mHwcContext->dpyAttr[HWC_DISPLAY_VIRTUAL].xres = priH;
- mHwcContext->dpyAttr[HWC_DISPLAY_VIRTUAL].yres = priW;
+ // downscale mode.
+ // DRC is only valid when the original resolution on the WiFi
+ // display is greater than the new resolution in mVInfo.
+ if(maxArea > (mVInfo.xres * mVInfo.yres)) {
+ if(maxArea == (priW * priH)) {
+ // Here we account for the case when primary resolution is
+ // greater than that of the WiFi display
+ w = priW;
+ h = priH;
+ // WFD is always in landscape, so always assign the higher
+ // dimension to wfd's xres
+ if(priH > priW) {
+ w = priH;
+ h = priW;
+ }
}
// Set External Display MDP Downscale mode indicator
mHwcContext->dpyAttr[HWC_DISPLAY_VIRTUAL].mDownScaleMode = true;