2 files changed, 36 insertions, 2 deletions

diff --git a/Documentation/devicetree/bindings/i2c/samsung-i2c.txt b/Documentation/devicetree/bindings/i2c/samsung-i2c.txt
index 38832c712919..b6cb5a12c672 100644
--- a/Documentation/devicetree/bindings/i2c/samsung-i2c.txt
+++ b/Documentation/devicetree/bindings/i2c/samsung-i2c.txt
@@ -6,14 +6,18 @@ Required properties:
   - compatible: value should be either of the following.
       (a) "samsung, s3c2410-i2c", for i2c compatible with s3c2410 i2c.
       (b) "samsung, s3c2440-i2c", for i2c compatible with s3c2440 i2c.
+      (c) "samsung, s3c2440-hdmiphy-i2c", for s3c2440-like i2c used
+          inside HDMIPHY block found on several samsung SoCs
   - reg: physical base address of the controller and length of memory mapped
     region.
   - interrupts: interrupt number to the cpu.
   - samsung,i2c-sda-delay: Delay (in ns) applied to data line (SDA) edges.
-  - gpios: The order of the gpios should be the following: <SDA, SCL>.
-    The gpio specifier depends on the gpio controller.
 
 Optional properties:
+  - gpios: The order of the gpios should be the following: <SDA, SCL>.
+    The gpio specifier depends on the gpio controller. Required in all
+    cases except for "samsung,s3c2440-hdmiphy-i2c" whose input/output
+    lines are permanently wired to the respective client
   - samsung,i2c-slave-addr: Slave address in multi-master enviroment. If not
     specified, default value is 0.
   - samsung,i2c-max-bus-freq: Desired frequency in Hz of the bus. If not
diff --git a/drivers/i2c/busses/i2c-s3c2410.c b/drivers/i2c/busses/i2c-s3c2410.c
index 23736ffaaa2a..fa0b13490873 100644
--- a/drivers/i2c/busses/i2c-s3c2410.c
+++ b/drivers/i2c/busses/i2c-s3c2410.c
@@ -46,6 +46,8 @@
 
 /* Treat S3C2410 as baseline hardware, anything else is supported via quirks */
 #define QUIRK_S3C2440           (1 << 0)
+#define QUIRK_HDMIPHY           (1 << 1)
+#define QUIRK_NO_GPIO           (1 << 2)
 
 /* i2c controller state */
 enum s3c24xx_i2c_state {
@@ -93,6 +95,9 @@ static struct platform_device_id s3c24xx_driver_ids[] = {
         }, {
                 .name           = "s3c2440-i2c",
                 .driver_data    = QUIRK_S3C2440,
+        }, {
+                .name           = "s3c2440-hdmiphy-i2c",
+                .driver_data    = QUIRK_S3C2440 | QUIRK_HDMIPHY | QUIRK_NO_GPIO,
         }, { },
 };
 MODULE_DEVICE_TABLE(platform, s3c24xx_driver_ids);
@@ -101,6 +106,8 @@ MODULE_DEVICE_TABLE(platform, s3c24xx_driver_ids);
 static const struct of_device_id s3c24xx_i2c_match[] = {
         { .compatible = "samsung,s3c2410-i2c", .data = (void *)0 },
         { .compatible = "samsung,s3c2440-i2c", .data = (void *)QUIRK_S3C2440 },
+        { .compatible = "samsung,s3c2440-hdmiphy-i2c",
+          .data = (void *)(QUIRK_S3C2440 | QUIRK_HDMIPHY | QUIRK_NO_GPIO) },
         {},
 };
 MODULE_DEVICE_TABLE(of, s3c24xx_i2c_match);
@@ -483,6 +490,13 @@ static int s3c24xx_i2c_set_master(struct s3c24xx_i2c *i2c)
         unsigned long iicstat;
         int timeout = 400;
 
+        /* the timeout for HDMIPHY is reduced to 10 ms because
+         * the hangup is expected to happen, so waiting 400 ms
+         * causes only unnecessary system hangup
+         */
+        if (i2c->quirks & QUIRK_HDMIPHY)
+                timeout = 10;
+
         while (timeout-- > 0) {
                 iicstat = readl(i2c->regs + S3C2410_IICSTAT);
 
@@ -492,6 +506,15 @@ static int s3c24xx_i2c_set_master(struct s3c24xx_i2c *i2c)
                 msleep(1);
         }
 
+        /* hang-up of bus dedicated for HDMIPHY occurred, resetting */
+        if (i2c->quirks & QUIRK_HDMIPHY) {
+                writel(0, i2c->regs + S3C2410_IICCON);
+                writel(0, i2c->regs + S3C2410_IICSTAT);
+                writel(0, i2c->regs + S3C2410_IICDS);
+
+                return 0;
+        }
+
         return -ETIMEDOUT;
 }
 
@@ -773,6 +796,9 @@ static int s3c24xx_i2c_parse_dt_gpio(struct s3c24xx_i2c *i2c)
 {
         int idx, gpio, ret;
 
+        if (i2c->quirks & QUIRK_NO_GPIO)
+                return 0;
+
         for (idx = 0; idx < 2; idx++) {
                 gpio = of_get_gpio(i2c->dev->of_node, idx);
                 if (!gpio_is_valid(gpio)) {
@@ -797,6 +823,10 @@ free_gpio:
 static void s3c24xx_i2c_dt_gpio_free(struct s3c24xx_i2c *i2c)
 {
         unsigned int idx;
+
+        if (i2c->quirks & QUIRK_NO_GPIO)
+                return;
+
         for (idx = 0; idx < 2; idx++)
                 gpio_free(i2c->gpios[idx]);
 }