diff options
| -rw-r--r-- | Documentation/devicetree/bindings/i2c/i2c-s3c2410.txt | 2 | ||||
| -rw-r--r-- | drivers/i2c/busses/i2c-s3c2410.c | 66 |
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); |