diff options
Diffstat (limited to 'drivers/i2c/i2c-uclass.c')
-rw-r--r-- | drivers/i2c/i2c-uclass.c | 44 |
1 files changed, 31 insertions, 13 deletions
diff --git a/drivers/i2c/i2c-uclass.c b/drivers/i2c/i2c-uclass.c index 2aa3efe8aa..e9ec388576 100644 --- a/drivers/i2c/i2c-uclass.c +++ b/drivers/i2c/i2c-uclass.c @@ -501,35 +501,53 @@ static int i2c_gpio_get_pin(struct gpio_desc *pin) return dm_gpio_get_value(pin); } -static int i2c_deblock_gpio_loop(struct gpio_desc *sda_pin, - struct gpio_desc *scl_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 counter = 9; - int ret = 0; + int i, ret = -EREMOTEIO; i2c_gpio_set_pin(sda_pin, 1); i2c_gpio_set_pin(scl_pin, 1); - udelay(5); + udelay(delay); /* Toggle SCL until slave release SDA */ - while (counter-- >= 0) { + while (scl_count-- >= 0) { i2c_gpio_set_pin(scl_pin, 1); - udelay(5); + udelay(delay); i2c_gpio_set_pin(scl_pin, 0); - udelay(5); - if (i2c_gpio_get_pin(sda_pin)) + udelay(delay); + 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 */ i2c_gpio_set_pin(sda_pin, 0); - udelay(5); + udelay(delay); i2c_gpio_set_pin(scl_pin, 1); - udelay(5); + udelay(delay); i2c_gpio_set_pin(sda_pin, 1); - udelay(5); + udelay(delay); if (!i2c_gpio_get_pin(sda_pin) || !i2c_gpio_get_pin(scl_pin)) ret = -EREMOTEIO; @@ -561,7 +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]); + ret0 = i2c_deblock_gpio_loop(&gpios[PIN_SDA], &gpios[PIN_SCL], 9, 0, 5); ret = pinctrl_select_state(bus, "default"); if (ret) { |