drm: bridge: dw-hdmi: optimize edid reading process

1.change SDA high level holding time to 3us.
2.when plug in,add timer to avoid unstable state.

Change-Id: Idc6faec710137ac9f8e589d75cbc1b85f7a45faf
Signed-off-by: algea.cao <algea.cao@rock-chips.com>

diff --git a/drivers/gpu/drm/bridge/dw-hdmi.c b/drivers/gpu/drm/bridge/dw-hdmi.c
index 3aa550748b1104f0dd27e17bf62c175faab241e5..aacccec78d48bc555c5304c07d45419f82ab0487 100644 (file)
--- a/drivers/gpu/drm/bridge/dw-hdmi.c
+++ b/drivers/gpu/drm/bridge/dw-hdmi.c
@@ -117,7 +117,6 @@ static const struct dw_hdmi_audio_tmds_n common_tmds_n_table[] = {
        { .tmds = 0,         .n_32k = 0,    .n_44k1 = 0,    .n_48k = 0, },
 };
 
-
 static const u16 csc_coeff_default[3][4] = {
        { 0x2000, 0x0000, 0x0000, 0x0000 },
        { 0x0000, 0x2000, 0x0000, 0x0000 },
@@ -208,6 +207,10 @@ struct dw_hdmi {
        void __iomem *regs;
        bool sink_is_hdmi;
        bool sink_has_audio;
+       bool hpd_state;
+
+       struct delayed_work work;
+       struct workqueue_struct *workqueue;
 
        struct mutex mutex;             /* for state below and previous_mode */
        enum drm_connector_force force; /* mutex-protected force state */
@@ -284,6 +287,48 @@ static void hdmi_mask_writeb(struct dw_hdmi *hdmi, u8 data, unsigned int reg,
        hdmi_modb(hdmi, data << shift, mask, reg);
 }
 
+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);
+#ifdef CONFIG_SWITCH
+       if (hdmi->hpd_state)
+               switch_set_state(&hdmi->switchdev, 1);
+       else
+               switch_set_state(&hdmi->switchdev, 0);
+#endif
+}
+
+static bool check_hdmi_irq(struct dw_hdmi *hdmi, int intr_stat,
+                          int phy_int_pol)
+{
+       int msecs;
+
+       /* To determine whether interrupt type is HPD */
+       if (!(intr_stat & HDMI_IH_PHY_STAT0_HPD))
+               return false;
+
+       if (phy_int_pol & HDMI_PHY_HPD) {
+               dev_dbg(hdmi->dev, "dw hdmi plug in\n");
+               msecs = 150;
+               hdmi->hpd_state = true;
+       } else {
+               dev_dbg(hdmi->dev, "dw hdmi plug out\n");
+               msecs = 20;
+               hdmi->hpd_state = false;
+       }
+       mod_delayed_work(hdmi->workqueue, &hdmi->work, msecs_to_jiffies(msecs));
+
+       return true;
+}
+
+static void init_hpd_work(struct dw_hdmi *hdmi)
+{
+       hdmi->workqueue = create_workqueue("hpd_queue");
+       INIT_DELAYED_WORK(&hdmi->work, repo_hpd_event);
+}
+
 static void dw_hdmi_i2c_set_divs(struct dw_hdmi *hdmi)
 {
        unsigned long clk_rate_khz;
@@ -349,6 +394,9 @@ static void dw_hdmi_i2c_init(struct dw_hdmi *hdmi)
        hdmi_writeb(hdmi, HDMI_IH_I2CM_STAT0_ERROR | HDMI_IH_I2CM_STAT0_DONE,
                    HDMI_IH_MUTE_I2CM_STAT0);
 
+       /* set SDA high level holding time */
+       hdmi_writeb(hdmi, 0x48, HDMI_I2CM_SDA_HOLD);
+
        dw_hdmi_i2c_set_divs(hdmi);
 }
 
@@ -2172,17 +2220,7 @@ static irqreturn_t dw_hdmi_irq(int irq, void *dev_id)
                mutex_unlock(&hdmi->mutex);
        }
 
-       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);
-#ifdef CONFIG_SWITCH
-               if (phy_int_pol & HDMI_PHY_HPD)
-                       switch_set_state(&hdmi->switchdev, 1);
-               else
-                       switch_set_state(&hdmi->switchdev, 0);
-#endif
-       }
+       check_hdmi_irq(hdmi, intr_stat, phy_int_pol);
 
        hdmi_writeb(hdmi, intr_stat, HDMI_IH_PHY_STAT0);
        hdmi_writeb(hdmi, ~(HDMI_IH_PHY_STAT0_HPD | HDMI_IH_PHY_STAT0_RX_SENSE),
@@ -2505,6 +2543,7 @@ int dw_hdmi_bind(struct device *dev, struct device *master,
                 hdmi_readb(hdmi, HDMI_PRODUCT_ID0),
                 hdmi_readb(hdmi, HDMI_PRODUCT_ID1));
 
+       init_hpd_work(hdmi);
        initialize_hdmi_ih_mutes(hdmi);
 
        ret = devm_request_threaded_irq(dev, irq, dw_hdmi_hardirq,

diff --git a/drivers/gpu/drm/bridge/dw-hdmi.h b/drivers/gpu/drm/bridge/dw-hdmi.h
index 36859b35ef8fe0fc7f3aa1827e7f53492d1ba2ce..70db49815fb6a65a60155b700adaf03f9f6f67cb 100644 (file)
--- a/drivers/gpu/drm/bridge/dw-hdmi.h
+++ b/drivers/gpu/drm/bridge/dw-hdmi.h
@@ -544,6 +544,7 @@
 #define HDMI_I2CM_FS_SCL_HCNT_0_ADDR            0x7E10
 #define HDMI_I2CM_FS_SCL_LCNT_1_ADDR            0x7E11
 #define HDMI_I2CM_FS_SCL_LCNT_0_ADDR            0x7E12
+#define HDMI_I2CM_SDA_HOLD                      0x7E13
 
 enum {