[PATCH v2 0/2] media: i2c: imx412: Add regulator control to imx412

[PATCH v2 0/2] media: i2c: imx412: Add regulator control to imx412

[Bryan O'Donoghue]

V2:
- Drops redundant verbage "Defintion of the" from each of the newly defined
  regulators - Krzysztof Kozlowski
- Adds Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
- "description: thing described" to the same line in new additions
  following the established way of doing it in this file - bod

V1:
The imx412 has three regulators which depending on platform may need to be
individually enabled.

- dovdd
- avdd
- dvdd

Existing code for an Intel platform doesn't appear to need to enable these
rails directly. On my reference hardware, a Qualcomm Thundercomm RB5 some
of these rails do need to be enabled individually.

Add in the above named rails as optional in the YAML in the first patch
along with code to switch them on in the second patch.

Existing imx412 users should get dummy regulators populated which the
regulator_bulk_enable()/regulator_bulk_disable() code can safely ignore.

Bryan O'Donoghue (2):
  media: dt-bindings: imx412: Add regulator descriptions
  media: i2c: imx412: Add bulk regulator support

 .../bindings/media/i2c/sony,imx412.yaml       | 12 ++++++++
 drivers/media/i2c/imx412.c                    | 30 +++++++++++++++++++
 2 files changed, 42 insertions(+)

-- 
2.35.1

[PATCH v2 1/2] media: dt-bindings: imx412: Add regulator descriptions

[Bryan O'Donoghue]

The imx412 like many I2C camera sensors has three voltage rails which
depending on platform may be necessary to switch power onto directly.

Add in as optional rails so as not to break anything for existing users.

Cc: Rob Herring <robh+dt@kernel.org>
Cc: Krzysztof Kozlowski <krzk+dt@kernel.org>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
---
 .../devicetree/bindings/media/i2c/sony,imx412.yaml       | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/Documentation/devicetree/bindings/media/i2c/sony,imx412.yaml b/Documentation/devicetree/bindings/media/i2c/sony,imx412.yaml
index afcf70947f7e..26d1807d0bb6 100644
--- a/Documentation/devicetree/bindings/media/i2c/sony,imx412.yaml
+++ b/Documentation/devicetree/bindings/media/i2c/sony,imx412.yaml
@@ -32,6 +32,15 @@ properties:
     description: Clock frequency 6MHz, 12MHz, 18MHz, 24MHz or 27MHz
     maxItems: 1
 
+  dovdd-supply:
+    description: Interface power supply.
+
+  avdd-supply:
+    description: Analog power supply.
+
+  dvdd-supply:
+    description: Digital power supply.
+
   reset-gpios:
     description: Reference to the GPIO connected to the XCLR pin, if any.
     maxItems: 1
-- 
2.35.1

[PATCH v2 2/2] media: i2c: imx412: Add bulk regulator support

[Bryan O'Donoghue]

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>
---
 drivers/media/i2c/imx412.c | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/drivers/media/i2c/imx412.c b/drivers/media/i2c/imx412.c
index be3f6ea55559..44b92718b6cf 100644
--- a/drivers/media/i2c/imx412.c
+++ b/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
@@ -128,6 +135,8 @@ struct imx412 {
 	struct media_pad pad;
 	struct gpio_desc *reset_gpio;
 	struct clk *inclk;
+	struct regulator_bulk_data supplies[ARRAY_SIZE(imx412_supply_names)];
+	int num_supplies;
 	struct v4l2_ctrl_handler ctrl_handler;
 	struct v4l2_ctrl *link_freq_ctrl;
 	struct v4l2_ctrl *pclk_ctrl;
@@ -946,6 +955,17 @@ static int imx412_parse_hw_config(struct imx412 *imx412)
 		return -EINVAL;
 	}
 
+	/* Get optional DT defined regulators */
+	imx412->num_supplies = ARRAY_SIZE(imx412_supply_names);
+	for (i = 0; i < imx412->num_supplies; i++)
+		imx412->supplies[i].supply = imx412_supply_names[i];
+
+	ret = devm_regulator_bulk_get(imx412->dev,
+				      imx412->num_supplies,
+				      imx412->supplies);
+	if (ret)
+		return ret;
+
 	ep = fwnode_graph_get_next_endpoint(fwnode, NULL);
 	if (!ep)
 		return -ENXIO;
@@ -1011,6 +1031,13 @@ static int imx412_power_on(struct device *dev)
 	struct imx412 *imx412 = to_imx412(sd);
 	int ret;
 
+	ret = regulator_bulk_enable(imx412->num_supplies,
+				    imx412->supplies);
+	if (ret < 0) {
+		dev_err(dev, "failed to enable regulators\n");
+		goto error_reset;
+	}
+
 	gpiod_set_value_cansleep(imx412->reset_gpio, 1);
 
 	ret = clk_prepare_enable(imx412->inclk);
@@ -1044,6 +1071,9 @@ static int imx412_power_off(struct device *dev)
 
 	clk_disable_unprepare(imx412->inclk);
 
+	regulator_bulk_disable(imx412->num_supplies,
+			       imx412->supplies);
+
 	return 0;
 }
 
-- 
2.35.1

Re: [PATCH v2 2/2] media: i2c: imx412: Add bulk regulator support

[Sakari Ailus]

Hi Bryan,

Thanks for the patch.

On Mon, Apr 11, 2022 at 02:31:31AM +0100, Bryan O'Donoghue wrote:
> 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>
> ---
>  drivers/media/i2c/imx412.c | 30 ++++++++++++++++++++++++++++++
>  1 file changed, 30 insertions(+)
> 
> diff --git a/drivers/media/i2c/imx412.c b/drivers/media/i2c/imx412.c
> index be3f6ea55559..44b92718b6cf 100644
> --- a/drivers/media/i2c/imx412.c
> +++ b/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
> @@ -128,6 +135,8 @@ struct imx412 {
>  	struct media_pad pad;
>  	struct gpio_desc *reset_gpio;
>  	struct clk *inclk;
> +	struct regulator_bulk_data supplies[ARRAY_SIZE(imx412_supply_names)];
> +	int num_supplies;

unsigned int

>  	struct v4l2_ctrl_handler ctrl_handler;
>  	struct v4l2_ctrl *link_freq_ctrl;
>  	struct v4l2_ctrl *pclk_ctrl;
> @@ -946,6 +955,17 @@ static int imx412_parse_hw_config(struct imx412 *imx412)
>  		return -EINVAL;
>  	}
>  
> +	/* Get optional DT defined regulators */
> +	imx412->num_supplies = ARRAY_SIZE(imx412_supply_names);
> +	for (i = 0; i < imx412->num_supplies; i++)
> +		imx412->supplies[i].supply = imx412_supply_names[i];
> +
> +	ret = devm_regulator_bulk_get(imx412->dev,
> +				      imx412->num_supplies,

Fits on previous line.

> +				      imx412->supplies);
> +	if (ret)
> +		return ret;
> +
>  	ep = fwnode_graph_get_next_endpoint(fwnode, NULL);
>  	if (!ep)
>  		return -ENXIO;
> @@ -1011,6 +1031,13 @@ static int imx412_power_on(struct device *dev)
>  	struct imx412 *imx412 = to_imx412(sd);
>  	int ret;
>  
> +	ret = regulator_bulk_enable(imx412->num_supplies,
> +				    imx412->supplies);
> +	if (ret < 0) {
> +		dev_err(dev, "failed to enable regulators\n");
> +		goto error_reset;

You can return here, without touching the GPIO.

> +	}
> +
>  	gpiod_set_value_cansleep(imx412->reset_gpio, 1);
>  
>  	ret = clk_prepare_enable(imx412->inclk);

Please do disable the regulators if clk_prepare_enable() fails.

> @@ -1044,6 +1071,9 @@ static int imx412_power_off(struct device *dev)
>  
>  	clk_disable_unprepare(imx412->inclk);
>  
> +	regulator_bulk_disable(imx412->num_supplies,
> +			       imx412->supplies);
> +
>  	return 0;
>  }
>  

-- 
Kind regards,

Sakari Ailus