drm: hdlcd: Revamp runtime power management
Because the HDLCD driver acts as a component master it can end
up enabling the runtime PM functionality before the encoders
are initialised. This can cause crashes if the component slave
never probes (missing module) or if the PM operations kick in
before the probe finishes.
Move the enabling of the runtime PM after the component master
has finished collecting the slave components and use the DRM
atomic helpers to suspend and resume the device.
Tested-by: Robin Murphy <Robin.Murphy@arm.com>
Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com>
diff --git a/drivers/gpu/drm/arm/hdlcd_crtc.c b/drivers/gpu/drm/arm/hdlcd_crtc.c
index fef1b04..d1e8d31 100644
--- a/drivers/gpu/drm/arm/hdlcd_crtc.c
+++ b/drivers/gpu/drm/arm/hdlcd_crtc.c
@@ -33,8 +33,17 @@
*
*/
+static void hdlcd_crtc_cleanup(struct drm_crtc *crtc)
+{
+ struct hdlcd_drm_private *hdlcd = crtc_to_hdlcd_priv(crtc);
+
+ /* stop the controller on cleanup */
+ hdlcd_write(hdlcd, HDLCD_REG_COMMAND, 0);
+ drm_crtc_cleanup(crtc);
+}
+
static const struct drm_crtc_funcs hdlcd_crtc_funcs = {
- .destroy = drm_crtc_cleanup,
+ .destroy = hdlcd_crtc_cleanup,
.set_config = drm_atomic_helper_set_config,
.page_flip = drm_atomic_helper_page_flip,
.reset = drm_atomic_helper_crtc_reset,
@@ -155,8 +164,8 @@
if (!crtc->primary->fb)
return;
- clk_disable_unprepare(hdlcd->clk);
hdlcd_write(hdlcd, HDLCD_REG_COMMAND, 0);
+ clk_disable_unprepare(hdlcd->clk);
drm_crtc_vblank_off(crtc);
}
@@ -294,16 +303,6 @@
return plane;
}
-void hdlcd_crtc_suspend(struct drm_crtc *crtc)
-{
- hdlcd_crtc_disable(crtc);
-}
-
-void hdlcd_crtc_resume(struct drm_crtc *crtc)
-{
- hdlcd_crtc_enable(crtc);
-}
-
int hdlcd_setup_crtc(struct drm_device *drm)
{
struct hdlcd_drm_private *hdlcd = drm->dev_private;