[media] adv7604: Add support for hardware reset

The part can be reset by a low pulse on the RESET pin (i.e. a hardware
reset) with a minimum width of 5 ms. It is recommended to wait 5 ms
after the low pulse before an I2C write is performed to the part.
For safety reasons, the delays will be between 5 and 10 ms.

The RESET pin can be tied high, so the GPIO is optional.

Signed-off-by: Dragos Bogdan <dragos.bogdan@analog.com>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
This commit is contained in:
Dragos Bogdan 2016-06-22 08:30:42 -03:00 committed by Mauro Carvalho Chehab
parent 20634fd1cd
commit f5591da992

View File

@ -164,6 +164,7 @@ struct adv76xx_state {
struct adv76xx_platform_data pdata;
struct gpio_desc *hpd_gpio[4];
struct gpio_desc *reset_gpio;
struct v4l2_subdev sd;
struct media_pad pads[ADV76XX_PAD_MAX];
@ -3018,6 +3019,19 @@ static int configure_regmaps(struct adv76xx_state *state)
return 0;
}
static void adv76xx_reset(struct adv76xx_state *state)
{
if (state->reset_gpio) {
/* ADV76XX can be reset by a low reset pulse of minimum 5 ms. */
gpiod_set_value_cansleep(state->reset_gpio, 0);
usleep_range(5000, 10000);
gpiod_set_value_cansleep(state->reset_gpio, 1);
/* It is recommended to wait 5 ms after the low pulse before */
/* an I2C write is performed to the ADV76XX. */
usleep_range(5000, 10000);
}
}
static int adv76xx_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
@ -3081,6 +3095,12 @@ static int adv76xx_probe(struct i2c_client *client,
if (state->hpd_gpio[i])
v4l_info(client, "Handling HPD %u GPIO\n", i);
}
state->reset_gpio = devm_gpiod_get_optional(&client->dev, "reset",
GPIOD_OUT_HIGH);
if (IS_ERR(state->reset_gpio))
return PTR_ERR(state->reset_gpio);
adv76xx_reset(state);
state->timings = cea640x480;
state->format = adv76xx_format_info(state, MEDIA_BUS_FMT_YUYV8_2X8);