UPSTREAM: drm: bridge: dw-hdmi: Don't forward HPD events to DRM core before attach

Hotplug events should only be forwarded to the DRM core by the interrupt
handler when the bridge has been attached, otherwise the DRM device
pointer will be NULL, resulting in a crash.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Jose Abreu <joabreu@synopsys.com>
Signed-off-by: Archit Taneja <architt@codeaurora.org>
Link: http://patchwork.freedesktop.org/patch/msgid/20170117082910.27023-7-laurent.pinchart+renesas@ideasonboard.com
Change-Id: Ic1387b5253d4586774cdb82e089effdd4104e380
Signed-off-by: Zheng Yang <zhengyang@rock-chips.com>
(cherry pick from ba5d7e6160b7aed4df92d1764aa90790db0e7996)

diff --git a/drivers/gpu/drm/bridge/dw-hdmi.c b/drivers/gpu/drm/bridge/dw-hdmi.c
index 3ec4d712c5b8edf73a9aea03011ca90bfeeeb7bd..99d51b21d077daf3eb840c0210da895d29dc8d23 100644 (file)
--- a/drivers/gpu/drm/bridge/dw-hdmi.c
+++ b/drivers/gpu/drm/bridge/dw-hdmi.c
@@ -291,7 +291,8 @@ static void repo_hpd_event(struct work_struct *p_work)
 {
        struct dw_hdmi *hdmi = container_of(p_work, struct dw_hdmi, work.work);
 
-       drm_helper_hpd_irq_event(hdmi->bridge.dev);
+       if (hdmi->bridge.dev)
+               drm_helper_hpd_irq_event(hdmi->bridge.dev);
 #ifdef CONFIG_SWITCH
        if (hdmi->hpd_state)
                switch_set_state(&hdmi->switchdev, 1);