diff --git a/drivers/media/i2c/ov5640.c b/drivers/media/i2c/ov5640.c index d82f250355ed..e1b8365fef58 100644 --- a/drivers/media/i2c/ov5640.c +++ b/drivers/media/i2c/ov5640.c @@ -2436,11 +2436,22 @@ static void ov5640_power(struct ov5640_dev *sensor, bool enable) gpiod_set_value_cansleep(sensor->pwdn_gpio, enable ? 0 : 1); } -static void ov5640_reset(struct ov5640_dev *sensor) +/* + * From section 2.7 power up sequence: + * t0 + t1 + t2 >= 5ms Delay from DOVDD stable to PWDN pull down + * t3 >= 1ms Delay from PWDN pull down to RESETB pull up + * t4 >= 20ms Delay from RESETB pull up to SCCB (i2c) stable + * + * Some modules don't expose RESETB/PWDN pins directly, instead providing a + * "PWUP" GPIO which is wired through appropriate delays and inverters to the + * pins. + * + * In such cases, this gpio should be mapped to pwdn_gpio in the driver, and we + * should still toggle the pwdn_gpio below with the appropriate delays, while + * the calls to reset_gpio will be ignored. + */ +static void ov5640_powerup_sequence(struct ov5640_dev *sensor) { - if (!sensor->reset_gpio) - return; - if (sensor->pwdn_gpio) { gpiod_set_value_cansleep(sensor->reset_gpio, 0); @@ -2489,8 +2500,7 @@ static int ov5640_set_power_on(struct ov5640_dev *sensor) goto xclk_off; } - ov5640_reset(sensor); - ov5640_power(sensor, true); + ov5640_powerup_sequence(sensor); ret = ov5640_init_slave_id(sensor); if (ret)