media: i2c: imx412: Add bulk regulator support

Depending on the platform we may need to enable and disable three separate
regulators for the imx412.

- DOVDD
Digital I/O power

- AVDD
Analog power

- DVDD
Digital core power

The addition of these regulators shouldn't affect existing users using
fixed-on/firmware-controlled regulators.
Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
Acked-by: Daniele Alessandrelli <daniele.alessandrelli@intel.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

drivers/media/i2c/imx412.c

@@ -11,6 +11,7 @@
 #include <linux/i2c.h>
 #include <linux/module.h>
 #include <linux/pm_runtime.h>
+#include <linux/regulator/consumer.h>
 
 #include <media/v4l2-ctrls.h>
 #include <media/v4l2-fwnode.h>
@@ -101,6 +102,12 @@ struct imx412_mode {
 	struct imx412_reg_list reg_list;
 };
 
+static const char * const imx412_supply_names[] = {
+	"dovdd",	/* Digital I/O power */
+	"avdd",		/* Analog power */
+	"dvdd",		/* Digital core power */
+};
+
 /**
  * struct imx412 - imx412 sensor device structure
  * @dev: Pointer to generic device
@@ -109,6 +116,7 @@ struct imx412_mode {
  * @pad: Media pad. Only one pad supported
  * @reset_gpio: Sensor reset gpio
  * @inclk: Sensor input clock
+ * @supplies: Regulator supplies
  * @ctrl_handler: V4L2 control handler
  * @link_freq_ctrl: Pointer to link frequency control
  * @pclk_ctrl: Pointer to pixel clock control
@@ -128,6 +136,7 @@ struct imx412 {
 	struct media_pad pad;
 	struct gpio_desc *reset_gpio;
 	struct clk *inclk;
+	struct regulator_bulk_data supplies[ARRAY_SIZE(imx412_supply_names)];
 	struct v4l2_ctrl_handler ctrl_handler;
 	struct v4l2_ctrl *link_freq_ctrl;
 	struct v4l2_ctrl *pclk_ctrl;
@@ -946,6 +955,16 @@ static int imx412_parse_hw_config(struct imx412 *imx412)
 		return -EINVAL;
 	}
 
+	/* Get optional DT defined regulators */
+	for (i = 0; i < ARRAY_SIZE(imx412_supply_names); i++)
+		imx412->supplies[i].supply = imx412_supply_names[i];
+
+	ret = devm_regulator_bulk_get(imx412->dev,
+				      ARRAY_SIZE(imx412_supply_names),
+				      imx412->supplies);
+	if (ret)
+		return ret;
+
 	ep = fwnode_graph_get_next_endpoint(fwnode, NULL);
 	if (!ep)
 		return -ENXIO;
@@ -1011,6 +1030,13 @@ static int imx412_power_on(struct device *dev)
 	struct imx412 *imx412 = to_imx412(sd);
 	int ret;
 
+	ret = regulator_bulk_enable(ARRAY_SIZE(imx412_supply_names),
+				    imx412->supplies);
+	if (ret < 0) {
+		dev_err(dev, "failed to enable regulators\n");
+		return ret;
+	}
+
 	gpiod_set_value_cansleep(imx412->reset_gpio, 0);
 
 	ret = clk_prepare_enable(imx412->inclk);
@@ -1025,6 +1051,8 @@ static int imx412_power_on(struct device *dev)
 
 error_reset:
 	gpiod_set_value_cansleep(imx412->reset_gpio, 1);
+	regulator_bulk_disable(ARRAY_SIZE(imx412_supply_names),
+			       imx412->supplies);
 
 	return ret;
 }
@@ -1044,6 +1072,9 @@ static int imx412_power_off(struct device *dev)
 
 	gpiod_set_value_cansleep(imx412->reset_gpio, 1);
 
+	regulator_bulk_disable(ARRAY_SIZE(imx412_supply_names),
+			       imx412->supplies);
+
 	return 0;
 }