[PATCH v5 3/6] [media] ad5820: Add support for enable pin

Ricardo Ribalda Delgado
2018-10-02T07:32:34Z

This patch adds support for a programmable enable pin. It can be used in
situations where the ANA-vcc is not configurable (dummy-regulator), or
just to have a more fine control of the power saving.

The use of the enable pin is optional.

Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
---
drivers/media/i2c/Kconfig | 2 +-
drivers/media/i2c/ad5820.c | 17 +++++++++++++++++
2 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
index bfdb494686bf..1ba6eaaf58fb 100644
--- a/drivers/media/i2c/Kconfig
+++ b/drivers/media/i2c/Kconfig
@@ -321,7 +321,7 @@ config VIDEO_ML86V7667

config VIDEO_AD5820
tristate "AD5820 lens voice coil support"
- depends on I2C && VIDEO_V4L2 && MEDIA_CONTROLLER
+ depends on GPIOLIB && I2C && VIDEO_V4L2 && MEDIA_CONTROLLER
---help---
This is a driver for the AD5820 camera lens voice coil.
It is used for example in Nokia N900 (RX-51).
diff --git a/drivers/media/i2c/ad5820.c b/drivers/media/i2c/ad5820.c
index 22759aaa2dba..97eb05e65833 100644
--- a/drivers/media/i2c/ad5820.c
+++ b/drivers/media/i2c/ad5820.c
@@ -27,6 +27,7 @@
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/regulator/consumer.h>
+#include <linux/gpio/consumer.h>

#include <media/v4l2-ctrls.h>
#include <media/v4l2-device.h>
@@ -55,6 +56,8 @@ struct ad5820_device {
u32 focus_ramp_time;
u32 focus_ramp_mode;

+ struct gpio_desc *enable_gpio;
+
struct mutex power_lock;
int power_count;

@@ -122,6 +125,8 @@ static int ad5820_power_off(struct ad5820_device *coil, bool standby)
ret = ad5820_update_hw(coil);
}

+ gpiod_set_value_cansleep(coil->enable_gpio, 0);
+
ret2 = regulator_disable(coil->vana);
if (ret)
return ret;
@@ -136,6 +141,8 @@ static int ad5820_power_on(struct ad5820_device *coil, bool restore)
if (ret < 0)
return ret;

+ gpiod_set_value_cansleep(coil->enable_gpio, 1);
+
if (restore) {
/* Restore the hardware settings. */
coil->standby = false;
@@ -146,6 +153,7 @@ static int ad5820_power_on(struct ad5820_device *coil, bool restore)
return 0;

fail:
+ gpiod_set_value_cansleep(coil->enable_gpio, 0);
coil->standby = true;
regulator_disable(coil->vana);

@@ -312,6 +320,15 @@ static int ad5820_probe(struct i2c_client *client,
return ret;
}

+ coil->enable_gpio = devm_gpiod_get_optional(&client->dev, "enable",
+ GPIOD_OUT_LOW);
+ if (IS_ERR(coil->enable_gpio)) {
+ ret = PTR_ERR(coil->enable_gpio);
+ if (ret != -EPROBE_DEFER)
+ dev_err(&client->dev, "could not get enable gpio\n");
+ return ret;
+ }
+
mutex_init(&coil->power_lock);

v4l2_i2c_subdev_init(&coil->subdev, client, &ad5820_ops);
--
2.19.0