diff options
author | Dragos Bogdan <dragos.bogdan@analog.com> | 2016-06-22 08:30:42 -0300 |
---|---|---|
committer | Mauro Carvalho Chehab <mchehab@s-opensource.com> | 2016-07-08 16:37:10 -0300 |
commit | f5591da992b952624cf191ed4988360f921e9e57 (patch) | |
tree | 73200e178fa0827b4e41677713ae080cb816f051 /drivers/media/i2c | |
parent | 20634fd1cd3b004088847318024a714f17f2d975 (diff) | |
download | linux-f5591da992b952624cf191ed4988360f921e9e57.tar.bz2 |
[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>
Diffstat (limited to 'drivers/media/i2c')
-rw-r--r-- | drivers/media/i2c/adv7604.c | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/drivers/media/i2c/adv7604.c b/drivers/media/i2c/adv7604.c index 3ffb3231be3f..0b362eeb55c7 100644 --- a/drivers/media/i2c/adv7604.c +++ b/drivers/media/i2c/adv7604.c @@ -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); |