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authorMarek Vasut <marex@denx.de>2020-02-07 16:57:51 +0100
committerHeiko Schocher <hs@denx.de>2020-03-16 07:46:21 +0100
commita19172863335dcaa1b2a98009f0bfef2a61ab4a2 (patch)
tree67558ece91aae82299ca1717470a16877658aff0 /drivers/i2c
parent7231522a5ed1545d3206f5204676897d62a24f5f (diff)
downloadu-boot-a19172863335dcaa1b2a98009f0bfef2a61ab4a2.tar.gz
i2c: Add option to send start condition after deblocking
Add option to send start condition after deblocking SDA. Signed-off-by: Marek Vasut <marex@denx.de> Reviewed-by: Heiko Schocher <hs@denx.de>
Diffstat (limited to 'drivers/i2c')
-rw-r--r--drivers/i2c/i2c-uclass.c23
1 files changed, 20 insertions, 3 deletions
diff --git a/drivers/i2c/i2c-uclass.c b/drivers/i2c/i2c-uclass.c
index 86f529241f..e9ec388576 100644
--- a/drivers/i2c/i2c-uclass.c
+++ b/drivers/i2c/i2c-uclass.c
@@ -504,9 +504,10 @@ static int i2c_gpio_get_pin(struct gpio_desc *pin)
int i2c_deblock_gpio_loop(struct gpio_desc *sda_pin,
struct gpio_desc *scl_pin,
unsigned int scl_count,
+ unsigned int start_count,
unsigned int delay)
{
- int ret = 0;
+ int i, ret = -EREMOTEIO;
i2c_gpio_set_pin(sda_pin, 1);
i2c_gpio_set_pin(scl_pin, 1);
@@ -518,8 +519,24 @@ int i2c_deblock_gpio_loop(struct gpio_desc *sda_pin,
udelay(delay);
i2c_gpio_set_pin(scl_pin, 0);
udelay(delay);
- if (i2c_gpio_get_pin(sda_pin))
+ if (i2c_gpio_get_pin(sda_pin)) {
+ ret = 0;
break;
+ }
+ }
+
+ if (!ret && start_count) {
+ for (i = 0; i < start_count; i++) {
+ /* Send start condition */
+ udelay(delay);
+ i2c_gpio_set_pin(sda_pin, 1);
+ udelay(delay);
+ i2c_gpio_set_pin(scl_pin, 1);
+ udelay(delay);
+ i2c_gpio_set_pin(sda_pin, 0);
+ udelay(delay);
+ i2c_gpio_set_pin(scl_pin, 0);
+ }
}
/* Then, send I2C stop */
@@ -562,7 +579,7 @@ static int i2c_deblock_gpio(struct udevice *bus)
goto out_no_pinctrl;
}
- ret0 = i2c_deblock_gpio_loop(&gpios[PIN_SDA], &gpios[PIN_SCL], 9, 5);
+ ret0 = i2c_deblock_gpio_loop(&gpios[PIN_SDA], &gpios[PIN_SCL], 9, 0, 5);
ret = pinctrl_select_state(bus, "default");
if (ret) {