2 files changed, 58 insertions, 10 deletions

diff --git a/Documentation/devicetree/bindings/i2c/i2c-s3c2410.txt b/Documentation/devicetree/bindings/i2c/i2c-s3c2410.txt
index 296eb4536129..278de8e64bbf 100644
--- a/Documentation/devicetree/bindings/i2c/i2c-s3c2410.txt
+++ b/Documentation/devicetree/bindings/i2c/i2c-s3c2410.txt
@@ -10,6 +10,8 @@ Required properties:
           inside HDMIPHY block found on several samsung SoCs
       (d) "samsung, exynos5440-i2c", for s3c2440-like i2c used
            on EXYNOS5440 which does not need GPIO configuration.
+      (e) "samsung, exynos5-sata-phy-i2c", for s3c2440-like i2c used as
+           a host to SATA PHY controller on an internal bus.
   - reg: physical base address of the controller and length of memory mapped
     region.
   - interrupts: interrupt number to the cpu.
diff --git a/drivers/i2c/busses/i2c-s3c2410.c b/drivers/i2c/busses/i2c-s3c2410.c
index bf8fb94ebc5d..09f251d0716f 100644
--- a/drivers/i2c/busses/i2c-s3c2410.c
+++ b/drivers/i2c/busses/i2c-s3c2410.c
@@ -86,6 +86,7 @@
 #define QUIRK_S3C2440           (1 << 0)
 #define QUIRK_HDMIPHY           (1 << 1)
 #define QUIRK_NO_GPIO           (1 << 2)
+#define QUIRK_POLL              (1 << 3)
 
 /* Max time to wait for bus to become idle after a xfer (in us) */
 #define S3C2410_IDLE_TIMEOUT    5000
@@ -142,6 +143,8 @@ static struct platform_device_id s3c24xx_driver_ids[] = {
 };
 MODULE_DEVICE_TABLE(platform, s3c24xx_driver_ids);
 
+static int i2c_s3c_irq_nextbyte(struct s3c24xx_i2c *i2c, unsigned long iicstat);
+
 #ifdef CONFIG_OF
 static const struct of_device_id s3c24xx_i2c_match[] = {
         { .compatible = "samsung,s3c2410-i2c", .data = (void *)0 },
@@ -150,6 +153,8 @@ static const struct of_device_id s3c24xx_i2c_match[] = {
           .data = (void *)(QUIRK_S3C2440 | QUIRK_HDMIPHY | QUIRK_NO_GPIO) },
         { .compatible = "samsung,exynos5440-i2c",
           .data = (void *)(QUIRK_S3C2440 | QUIRK_NO_GPIO) },
+        { .compatible = "samsung,exynos5-sata-phy-i2c",
+          .data = (void *)(QUIRK_S3C2440 | QUIRK_POLL | QUIRK_NO_GPIO) },
         {},
 };
 MODULE_DEVICE_TABLE(of, s3c24xx_i2c_match);
@@ -188,7 +193,8 @@ static inline void s3c24xx_i2c_master_complete(struct s3c24xx_i2c *i2c, int ret)
         if (ret)
                 i2c->msg_idx = ret;
 
-        wake_up(&i2c->wait);
+        if (!(i2c->quirks & QUIRK_POLL))
+                wake_up(&i2c->wait);
 }
 
 static inline void s3c24xx_i2c_disable_ack(struct s3c24xx_i2c *i2c)
@@ -225,6 +231,22 @@ static inline void s3c24xx_i2c_enable_irq(struct s3c24xx_i2c *i2c)
         writel(tmp | S3C2410_IICCON_IRQEN, i2c->regs + S3C2410_IICCON);
 }
 
+static bool is_ack(struct s3c24xx_i2c *i2c)
+{
+        int tries;
+
+        for (tries = 50; tries; --tries) {
+                if (readl(i2c->regs + S3C2410_IICCON)
+                        & S3C2410_IICCON_IRQPEND) {
+                        if (!(readl(i2c->regs + S3C2410_IICSTAT)
+                                & S3C2410_IICSTAT_LASTBIT))
+                                return true;
+                }
+                usleep_range(1000, 2000);
+        }
+        dev_err(i2c->dev, "ack was not recieved\n");
+        return false;
+}
 
 /* s3c24xx_i2c_message_start
  *
@@ -269,6 +291,16 @@ static void s3c24xx_i2c_message_start(struct s3c24xx_i2c *i2c,
 
         stat |= S3C2410_IICSTAT_START;
         writel(stat, i2c->regs + S3C2410_IICSTAT);
+
+        if (i2c->quirks & QUIRK_POLL) {
+                while ((i2c->msg_num != 0) && is_ack(i2c)) {
+                        i2c_s3c_irq_nextbyte(i2c, stat);
+                        stat = readl(i2c->regs + S3C2410_IICSTAT);
+
+                        if (stat & S3C2410_IICSTAT_ARBITR)
+                                dev_err(i2c->dev, "deal with arbitration loss\n");
+                }
+        }
 }
 
 static inline void s3c24xx_i2c_stop(struct s3c24xx_i2c *i2c, int ret)
@@ -676,6 +708,15 @@ static int s3c24xx_i2c_doxfer(struct s3c24xx_i2c *i2c,
         s3c24xx_i2c_enable_irq(i2c);
         s3c24xx_i2c_message_start(i2c, msgs);
 
+        if (i2c->quirks & QUIRK_POLL) {
+                ret = i2c->msg_idx;
+
+                if (ret != num)
+                        dev_dbg(i2c->dev, "incomplete xfer (%d)\n", ret);
+
+                goto out;
+        }
+
         timeout = wait_event_timeout(i2c->wait, i2c->msg_num == 0, HZ * 5);
 
         ret = i2c->msg_idx;
@@ -821,6 +862,9 @@ static int s3c24xx_i2c_clockrate(struct s3c24xx_i2c *i2c, unsigned int *got)
         if (div1 == 512)
                 iiccon |= S3C2410_IICCON_TXDIV_512;
 
+        if (i2c->quirks & QUIRK_POLL)
+                iiccon |= S3C2410_IICCON_SCALE(2);
+
         writel(iiccon, i2c->regs + S3C2410_IICCON);
 
         if (i2c->quirks & QUIRK_S3C2440) {
@@ -1118,18 +1162,20 @@ static int s3c24xx_i2c_probe(struct platform_device *pdev)
          * ensure no current IRQs pending
          */
 
-        i2c->irq = ret = platform_get_irq(pdev, 0);
-        if (ret <= 0) {
-                dev_err(&pdev->dev, "cannot find IRQ\n");
-                return ret;
-        }
+        if (!(i2c->quirks & QUIRK_POLL)) {
+                i2c->irq = ret = platform_get_irq(pdev, 0);
+                if (ret <= 0) {
+                        dev_err(&pdev->dev, "cannot find IRQ\n");
+                        return ret;
+                }
 
         ret = devm_request_irq(&pdev->dev, i2c->irq, s3c24xx_i2c_irq, 0,
-                               dev_name(&pdev->dev), i2c);
+                                dev_name(&pdev->dev), i2c);
 
-        if (ret != 0) {
-                dev_err(&pdev->dev, "cannot claim IRQ %d\n", i2c->irq);
-                return ret;
+                if (ret != 0) {
+                        dev_err(&pdev->dev, "cannot claim IRQ %d\n", i2c->irq);
+                        return ret;
+                }
         }
 
         ret = s3c24xx_i2c_register_cpufreq(i2c);