drm/msm/hdmi: Fix connector detect when there is no HPD gpio

Some platforms may not have a HPD gpio line to detect Hot Plug signal from
the connector. They need to rely only on reading REG_HDMI_HPD_INT_STATUS
for HPD.

Modify hdmi_connector_detect logic such that it checks for HPD only using
the status register if there is no HPD gpio.

Signed-off-by: Archit Taneja <architt@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>

diff --git a/drivers/gpu/drm/msm/hdmi/hdmi_connector.c b/drivers/gpu/drm/msm/hdmi/hdmi_connector.c
index deec1f9..3973d46 100644 (file)
--- a/drivers/gpu/drm/msm/hdmi/hdmi_connector.c
+++ b/drivers/gpu/drm/msm/hdmi/hdmi_connector.c
@@ -301,9 +301,18 @@ static enum drm_connector_status hdmi_connector_detect(
 {
        struct hdmi_connector *hdmi_connector = to_hdmi_connector(connector);
        struct hdmi *hdmi = hdmi_connector->hdmi;
+       const struct hdmi_platform_config *config = hdmi->config;
+       struct hdmi_gpio_data hpd_gpio = config->gpios[HPD_GPIO_INDEX];
        enum drm_connector_status stat_gpio, stat_reg;
        int retry = 20;
 
+       /*
+        * some platforms may not have hpd gpio. Rely only on the status
+        * provided by REG_HDMI_HPD_INT_STATUS in this case.
+        */
+       if (hpd_gpio.num == -1)
+               return detect_reg(hdmi);
+
        do {
                stat_gpio = detect_gpio(hdmi);
                stat_reg  = detect_reg(hdmi);