Hi Roman,
On Tue, May 19, 2020 at 04:16:17AM +0300, Roman Kovalivskyi wrote:
> From: Dave Stevenson <dave.stevenson@xxxxxxxxxxxxxxx>
>
> Add support for an optional GPIO connected to PWDN on the sensor. This
> allows the use of hardware standby mode where internal device clock
> and circuit activities are halted.
>
> Please nothe that power is off when PWDN is high.
>
> Signed-off-by: Dave Stevenson <dave.stevenson@xxxxxxxxxxxxxxx>
> Signed-off-by: Roman Kovalivskyi <roman.kovalivskyi@xxxxxxxxxxxxxxx>
> ---
> drivers/media/i2c/ov5647.c | 33 +++++++++++++++++++++++++++++++++
> 1 file changed, 33 insertions(+)
>
> diff --git a/drivers/media/i2c/ov5647.c b/drivers/media/i2c/ov5647.c
> index 3e587eb0a30e..796cc80f8ee1 100644
> --- a/drivers/media/i2c/ov5647.c
> +++ b/drivers/media/i2c/ov5647.c
> @@ -21,6 +21,7 @@
>
> #include <linux/clk.h>
> #include <linux/delay.h>
> +#include <linux/gpio/consumer.h>
> #include <linux/i2c.h>
> #include <linux/init.h>
> #include <linux/io.h>
> @@ -35,6 +36,13 @@
>
> #define SENSOR_NAME "ov5647"
>
> +/*
> + * From the datasheet, "20ms after PWDN goes low or 20ms after RESETB goes
> + * high if reset is inserted after PWDN goes high, host can access sensor's
> + * SCCB to initialize sensor."
> + */
> +#define PWDN_ACTIVE_DELAY_MS 20
> +
> #define MIPI_CTRL00_CLOCK_LANE_GATE BIT(5)
> #define MIPI_CTRL00_BUS_IDLE BIT(2)
> #define MIPI_CTRL00_CLOCK_LANE_DISABLE BIT(0)
> @@ -86,6 +94,7 @@ struct ov5647 {
> unsigned int height;
> int power_count;
> struct clk *xclk;
> + struct gpio_desc *pwdn;
> };
>
> static inline struct ov5647 *to_state(struct v4l2_subdev *sd)
> @@ -93,6 +102,11 @@ static inline struct ov5647 *to_state(struct v4l2_subdev *sd)
> return container_of(sd, struct ov5647, sd);
> }
>
> +static inline void msleep_range(unsigned int delay_base)
> +{
> + usleep_range(delay_base * 1000, delay_base * 1000 + 5000);
> +}
> +
I think I mis-lead you with the comment I gave on v1, as I just notice
the designated timeout is 20 msec, so msleep() is fine. Sorry about
this, I thought we were dealing with a shorter interval.
If that's ok with you I'll send a v3 of this series with Sakari's
comments addressed, rebased on top of the yaml version of the sensor
bindings I sent out a few hours ago.
Thanks
j
> static struct regval_list sensor_oe_disable_regs[] = {
> {0x3000, 0x00},
> {0x3001, 0x00},
> @@ -355,6 +369,11 @@ static int ov5647_sensor_power(struct v4l2_subdev *sd, int on)
> if (on && !ov5647->power_count) {
> dev_dbg(&client->dev, "OV5647 power on\n");
>
> + if (ov5647->pwdn) {
> + gpiod_set_value(ov5647->pwdn, 0);
> + msleep_range(PWDN_ACTIVE_DELAY_MS);
> + }
> +
> ret = clk_prepare_enable(ov5647->xclk);
> if (ret < 0) {
> dev_err(&client->dev, "clk prepare enable failed\n");
> @@ -392,6 +411,8 @@ static int ov5647_sensor_power(struct v4l2_subdev *sd, int on)
> dev_dbg(&client->dev, "soft stby failed\n");
>
> clk_disable_unprepare(ov5647->xclk);
> +
> + gpiod_set_value(ov5647->pwdn, 1);
> }
>
> /* Update the power count. */
> @@ -603,6 +624,10 @@ static int ov5647_probe(struct i2c_client *client)
> return -EINVAL;
> }
>
> + /* Request the power down GPIO asserted */
> + sensor->pwdn = devm_gpiod_get_optional(&client->dev, "pwdn",
> + GPIOD_OUT_HIGH);
> +
> mutex_init(&sensor->lock);
>
> sd = &sensor->sd;
> @@ -616,7 +641,15 @@ static int ov5647_probe(struct i2c_client *client)
> if (ret < 0)
> goto mutex_remove;
>
> + if (sensor->pwdn) {
> + gpiod_set_value(sensor->pwdn, 0);
> + msleep_range(PWDN_ACTIVE_DELAY_MS);
> + }
> +
> ret = ov5647_detect(sd);
> +
> + gpiod_set_value(sensor->pwdn, 1);
> +
> if (ret < 0)
> goto error;
>
> --
> 2.17.1
>
