summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--Documentation/devicetree/bindings/i2c/samsung-i2c.txt8
-rw-r--r--drivers/i2c/busses/i2c-s3c2410.c30
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 38832c7..b6cb5a1 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 23736ff..fa0b134 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]);
}
OpenPOWER on IntegriCloud