video: exynos_dp: Enable hotplug interrupts

Enable hotplug interrupts and move the hotplug scheduling into the
interrupt handler. This allows us to introduce a screen at any time
while we're running.

[jg1.han@samsung.com: moved the bit masking of hotplug interrupts]
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Reviewed-by: Olof Johansson <olofj@chromium.org>
Signed-off-by: Jingoo Han <jg1.han@samsung.com>

diff --git a/drivers/video/exynos/exynos_dp_core.c b/drivers/video/exynos/exynos_dp_core.c
index 617ba9568f0c4df9e59331de5eff087fee25cde1..ebd914dd7252056e4abade30efda5870d563bc4a 100644 (file)
--- a/drivers/video/exynos/exynos_dp_core.c
+++ b/drivers/video/exynos/exynos_dp_core.c
@@ -49,10 +49,6 @@ static int exynos_dp_detect_hpd(struct exynos_dp_device *dp)
 {
        int timeout_loop = 0;
 
-       exynos_dp_init_hpd(dp);
-
-       usleep_range(200, 210);
-
        while (exynos_dp_get_plug_in_status(dp) != 0) {
                timeout_loop++;
                if (DP_TIMEOUT_LOOP_COUNT < timeout_loop) {
@@ -834,7 +830,32 @@ static irqreturn_t exynos_dp_irq_handler(int irq, void *arg)
 {
        struct exynos_dp_device *dp = arg;
 
-       dev_err(dp->dev, "exynos_dp_irq_handler\n");
+       enum dp_irq_type irq_type;
+
+       irq_type = exynos_dp_get_irq_type(dp);
+       switch (irq_type) {
+       case DP_IRQ_TYPE_HP_CABLE_IN:
+               dev_dbg(dp->dev, "Received irq - cable in\n");
+               schedule_work(&dp->hotplug_work);
+               exynos_dp_clear_hotplug_interrupts(dp);
+               break;
+       case DP_IRQ_TYPE_HP_CABLE_OUT:
+               dev_dbg(dp->dev, "Received irq - cable out\n");
+               exynos_dp_clear_hotplug_interrupts(dp);
+               break;
+       case DP_IRQ_TYPE_HP_CHANGE:
+               /*
+                * We get these change notifications once in a while, but there
+                * is nothing we can do with them. Just ignore it for now and
+                * only handle cable changes.
+                */
+               dev_dbg(dp->dev, "Received irq - hotplug change; ignoring.\n");
+               exynos_dp_clear_hotplug_interrupts(dp);
+               break;
+       default:
+               dev_err(dp->dev, "Received irq - unknown type!\n");
+               break;
+       }
        return IRQ_HANDLED;
 }
 
@@ -847,7 +868,7 @@ static void exynos_dp_hotplug(struct work_struct *work)
 
        ret = exynos_dp_detect_hpd(dp);
        if (ret) {
-               dev_err(dp->dev, "unable to detect hpd\n");
+               /* Cable has been disconnected, we're done */
                return;
        }
 
@@ -1093,7 +1114,6 @@ static int __devinit exynos_dp_probe(struct platform_device *pdev)
        exynos_dp_init_dp(dp);
 
        platform_set_drvdata(pdev, dp);
-       schedule_work(&dp->hotplug_work);
 
        return 0;
 }
@@ -1103,6 +1123,8 @@ static int __devexit exynos_dp_remove(struct platform_device *pdev)
        struct exynos_dp_platdata *pdata = pdev->dev.platform_data;
        struct exynos_dp_device *dp = platform_get_drvdata(pdev);
 
+       disable_irq(dp->irq);
+
        if (work_pending(&dp->hotplug_work))
                flush_work(&dp->hotplug_work);
 
@@ -1159,7 +1181,7 @@ static int exynos_dp_resume(struct device *dev)
 
        exynos_dp_init_dp(dp);
 
-       schedule_work(&dp->hotplug_work);
+       enable_irq(dp->irq);
 
        return 0;
 }

diff --git a/drivers/video/exynos/exynos_dp_core.h b/drivers/video/exynos/exynos_dp_core.h
index 5ef7135039fab81a0adcf954f43a39bbb0dd841b..ef3bb545f9a95471bddf4f319b2124d70f79eee5 100644 (file)
--- a/drivers/video/exynos/exynos_dp_core.h
+++ b/drivers/video/exynos/exynos_dp_core.h
@@ -13,6 +13,13 @@
 #ifndef _EXYNOS_DP_CORE_H
 #define _EXYNOS_DP_CORE_H
 
+enum dp_irq_type {
+       DP_IRQ_TYPE_HP_CABLE_IN,
+       DP_IRQ_TYPE_HP_CABLE_OUT,
+       DP_IRQ_TYPE_HP_CHANGE,
+       DP_IRQ_TYPE_UNKNOWN,
+};
+
 struct link_train {
        int eq_loop;
        int cr_loop[4];
@@ -53,6 +60,8 @@ void exynos_dp_set_analog_power_down(struct exynos_dp_device *dp,
                                bool enable);
 void exynos_dp_init_analog_func(struct exynos_dp_device *dp);
 void exynos_dp_init_hpd(struct exynos_dp_device *dp);
+enum dp_irq_type exynos_dp_get_irq_type(struct exynos_dp_device *dp);
+void exynos_dp_clear_hotplug_interrupts(struct exynos_dp_device *dp);
 void exynos_dp_reset_aux(struct exynos_dp_device *dp);
 void exynos_dp_init_aux(struct exynos_dp_device *dp);
 int exynos_dp_get_plug_in_status(struct exynos_dp_device *dp);

diff --git a/drivers/video/exynos/exynos_dp_reg.c b/drivers/video/exynos/exynos_dp_reg.c
index fc19ef651565b6a95bbd04ff4da80791f2365da9..9fb901bcdd59e8113fc0aa7051c94a92784e3ea9 100644 (file)
--- a/drivers/video/exynos/exynos_dp_reg.c
+++ b/drivers/video/exynos/exynos_dp_reg.c
@@ -19,11 +19,11 @@
 #include "exynos_dp_core.h"
 #include "exynos_dp_reg.h"
 
-#define COMMON_INT_MASK_1 (0)
-#define COMMON_INT_MASK_2 (0)
-#define COMMON_INT_MASK_3 (0)
-#define COMMON_INT_MASK_4 (0)
-#define INT_STA_MASK (0)
+#define COMMON_INT_MASK_1      0
+#define COMMON_INT_MASK_2      0
+#define COMMON_INT_MASK_3      0
+#define COMMON_INT_MASK_4      (HOTPLUG_CHG | HPD_LOST | PLUG)
+#define INT_STA_MASK           INT_HPD
 
 void exynos_dp_enable_video_mute(struct exynos_dp_device *dp, bool enable)
 {
@@ -324,7 +324,7 @@ void exynos_dp_init_analog_func(struct exynos_dp_device *dp)
        writel(reg, dp->reg_base + EXYNOS_DP_FUNC_EN_2);
 }
 
-void exynos_dp_init_hpd(struct exynos_dp_device *dp)
+void exynos_dp_clear_hotplug_interrupts(struct exynos_dp_device *dp)
 {
        u32 reg;
 
@@ -333,12 +333,38 @@ void exynos_dp_init_hpd(struct exynos_dp_device *dp)
 
        reg = INT_HPD;
        writel(reg, dp->reg_base + EXYNOS_DP_INT_STA);
+}
+
+void exynos_dp_init_hpd(struct exynos_dp_device *dp)
+{
+       u32 reg;
+
+       exynos_dp_clear_hotplug_interrupts(dp);
 
        reg = readl(dp->reg_base + EXYNOS_DP_SYS_CTL_3);
        reg &= ~(F_HPD | HPD_CTRL);
        writel(reg, dp->reg_base + EXYNOS_DP_SYS_CTL_3);
 }
 
+enum dp_irq_type exynos_dp_get_irq_type(struct exynos_dp_device *dp)
+{
+       u32 reg;
+
+       /* Parse hotplug interrupt status register */
+       reg = readl(dp->reg_base + EXYNOS_DP_COMMON_INT_STA_4);
+
+       if (reg & PLUG)
+               return DP_IRQ_TYPE_HP_CABLE_IN;
+
+       if (reg & HPD_LOST)
+               return DP_IRQ_TYPE_HP_CABLE_OUT;
+
+       if (reg & HOTPLUG_CHG)
+               return DP_IRQ_TYPE_HP_CHANGE;
+
+       return DP_IRQ_TYPE_UNKNOWN;
+}
+
 void exynos_dp_reset_aux(struct exynos_dp_device *dp)
 {
        u32 reg;