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

diff --git a/drivers/gpu/drm/bridge/dw-hdmi.c b/drivers/gpu/drm/bridge/dw-hdmi.c
index ef10bb8..488dc1a 100644 (file)
--- a/drivers/gpu/drm/bridge/dw-hdmi.c
+++ b/drivers/gpu/drm/bridge/dw-hdmi.c
@@ -1805,7 +1805,8 @@ static irqreturn_t dw_hdmi_irq(int irq, void *dev_id)
        if (intr_stat & HDMI_IH_PHY_STAT0_HPD) {
                dev_dbg(hdmi->dev, "EVENT=%s\n",
                        phy_int_pol & HDMI_PHY_HPD ? "plugin" : "plugout");
-               drm_helper_hpd_irq_event(hdmi->bridge.dev);
+               if (hdmi->bridge.dev)
+                       drm_helper_hpd_irq_event(hdmi->bridge.dev);
        }
 
        hdmi_writeb(hdmi, intr_stat, HDMI_IH_PHY_STAT0);