Hi Dafna,
On Thu, Jul 09, 2020 at 10:04:14PM +0200, Dafna Hirschfeld wrote:
>
>
> On 23.06.20 12:07, Jacopo Mondi 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 note that power is off when PWDN is high.
> >
> > Signed-off-by: Dave Stevenson <dave.stevenson@xxxxxxxxxxxxxxx>
> > Signed-off-by: Roman Kovalivskyi <roman.kovalivskyi@xxxxxxxxxxxxxxx>
> > Signed-off-by: Jacopo Mondi <jacopo@xxxxxxxxxx>
> > ---
> > drivers/media/i2c/ov5647.c | 28 ++++++++++++++++++++++++++++
> > 1 file changed, 28 insertions(+)
> >
> > diff --git a/drivers/media/i2c/ov5647.c b/drivers/media/i2c/ov5647.c
> > index e7d2e5b4ad4b9..105ff7f899b34 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)
> > @@ -355,6 +364,11 @@ 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_cansleep(ov5647->pwdn, 0);
> > + msleep(PWDN_ACTIVE_DELAY_MS);
> > + }
> > +
> > ret = clk_prepare_enable(ov5647->xclk);
> > if (ret < 0) {
> > dev_err(&client->dev, "clk prepare enable failed\n");
> > @@ -392,6 +406,8 @@ 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_cansleep(ov5647->pwdn, 1);
> > }
> > /* Update the power count. */
> > @@ -581,6 +597,10 @@ 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);
>
> Hi,
> I see that other drivers check for error from 'devm_gpiod_get_optional'
> using 'IS_ERR'
Thanks for noticing. It's probably worth adding a check for this.
I'll fix in v2.
Thanks
j
>
> Thanks,
> Dafna
>
> > +
> > mutex_init(&sensor->lock);
> > sd = &sensor->sd;
> > @@ -594,7 +614,15 @@ static int ov5647_probe(struct i2c_client *client)
> > if (ret < 0)
> > goto mutex_remove;
> > + if (sensor->pwdn) {
> > + gpiod_set_value_cansleep(sensor->pwdn, 0);
> > + msleep(PWDN_ACTIVE_DELAY_MS);
> > + }
> > +
> > ret = ov5647_detect(sd);
> > +
> > + gpiod_set_value_cansleep(sensor->pwdn, 1);
> > +
> > if (ret < 0)
> > goto error;
> >
