Re: [PATCH v2 1/1] leds: pca9532: Add device tree binding

[Jacek Anaszewski <j.anaszewski@samsung.com>]

Hi Phil,

Thanks for the update. Few more remarks below.

On 04/07/2016 09:22 AM, Phil Reid wrote:
> This patch adds basic device tree support for the pca9532 LEDs.
>
> Signed-off-by: Phil Reid <preid@electromag.com.au>
> ---
>   .../devicetree/bindings/leds/leds-pca9532.txt      | 42 +++++++++++++
>   drivers/leds/leds-pca9532.c                        | 69 ++++++++++++++++++++--
>   include/dt-bindings/leds/leds-pca9532.h            | 23 ++++++++
>   include/linux/leds-pca9532.h                       | 18 ++----
>   4 files changed, 135 insertions(+), 17 deletions(-)
>   create mode 100644 Documentation/devicetree/bindings/leds/leds-pca9532.txt
>   create mode 100644 include/dt-bindings/leds/leds-pca9532.h
>
> diff --git a/Documentation/devicetree/bindings/leds/leds-pca9532.txt b/Documentation/devicetree/bindings/leds/leds-pca9532.txt
> new file mode 100644
> index 0000000..284b96c
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/leds/leds-pca9532.txt
> @@ -0,0 +1,42 @@
> +*NXP - pca9532 PWM LED Driver
> +
> +The PCA9532 family is SMBus I/O expander optimized for dimming LEDs.
> +The PWM support 256 steps.
> +
> +Required properties:
> +	- compatible:
> +		"nxp,pca9530"
> +		"nxp,pca9531"
> +		"nxp,pca9532"
> +		"nxp,pca9533"
> +	- reg -  I2C slave address
> +
> +Each led is represented as a sub-node of the nxp,pca9530.
> +
> +Optional sub-node properties:
> +	- label: Name for this LED. If omitted, the label is taken from the node name.

Please also add a reference to common led bindings, as this property is
documented there:
"(see Documentation/devicetree/bindings/leds/common.txt):"

> +	- type: Output configuration, see dt-bindings/leds/leds-pca9532.h (default NONE)
> +	- state: Initial LED state (default OFF)

We already have "default-on" trigger for this purpose.

> +	- linux,default-trigger: Trigger assigned to the LED.

Please also add a reference to common led bindings, as this property is
documented there:
"(see Documentation/devicetree/bindings/leds/common.txt):"

default-on trigger is also mentioned there.

> +
> +Example:
> +  #include <dt-bindings/leds/leds-pca9532.h>
> +
> +  leds: pca9530@60 {
> +    compatible = "nxp,pca9530";
> +    reg = <0x60>;
> +
> +    red-power {
> +      label = "pca:red:power";
> +      type = <PCA9532_TYPE_LED>;
> +      state = <PCA9532_PWM0>;
> +    };
> +    green-power {
> +      label = "pca:green:power";
> +      type = <PCA9532_TYPE_LED>;
> +      state = <PCA9532_PWM1>;
> +    };
> +  };
> +
> +For more product information please see the link below:
> +http://nxp.com/documents/data_sheet/PCA9532.pdf
> diff --git a/drivers/leds/leds-pca9532.c b/drivers/leds/leds-pca9532.c
> index e3d3b1a..3bbaa39 100644
> --- a/drivers/leds/leds-pca9532.c
> +++ b/drivers/leds/leds-pca9532.c
> @@ -21,6 +21,8 @@
>   #include <linux/workqueue.h>
>   #include <linux/leds-pca9532.h>
>   #include <linux/gpio.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
>
>   /* m =  num_leds*/
>   #define PCA9532_REG_INPUT(i)	((i) >> 3)
> @@ -86,9 +88,22 @@ static const struct pca9532_chip_info pca9532_chip_info_tbl[] = {
>   	},
>   };
>
> +#ifdef CONFIG_OF
> +static const struct of_device_id of_pca9532_leds_match[] = {
> +	{ .compatible = "nxp,pca9530", .data = (void *)pca9530 },
> +	{ .compatible = "nxp,pca9531", .data = (void *)pca9531 },
> +	{ .compatible = "nxp,pca9532", .data = (void *)pca9532 },
> +	{ .compatible = "nxp,pca9533", .data = (void *)pca9533 },
> +	{},
> +};
> +
> +MODULE_DEVICE_TABLE(of, of_pca9532_leds_match);
> +#endif
> +
>   static struct i2c_driver pca9532_driver = {
>   	.driver = {
>   		.name = "leds-pca953x",
> +		.of_match_table = of_match_ptr(of_pca9532_leds_match),
>   	},
>   	.probe = pca9532_probe,
>   	.remove = pca9532_remove,
> @@ -354,6 +369,7 @@ static int pca9532_configure(struct i2c_client *client,
>   			led->state = pled->state;
>   			led->name = pled->name;
>   			led->ldev.name = led->name;
> +			led->ldev.default_trigger = led->default_trigger;
>   			led->ldev.brightness = LED_OFF;
>   			led->ldev.brightness_set_blocking =
>   						pca9532_set_brightness;
> @@ -432,15 +448,60 @@ exit:
>   	return err;
>   }
>
> +struct pca9532_platform_data *pca9532_of_populate_pdata(struct device *dev,
> +						      struct device_node *np)

This function is local and therefore should be static.

> +{
> +	struct pca9532_platform_data *pdata;
> +	struct device_node *child;
> +	int devid = (int)of_match_device(of_pca9532_leds_match, dev)->data;
> +	int maxleds = pca9532_chip_info_tbl[devid].num_leds;
> +	int i = 0;
> +
> +	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
> +	if (!pdata)
> +		return ERR_PTR(-ENOMEM);
> +
> +	for_each_child_of_node(np, child) {
> +		if (of_property_read_string(child, "label",
> +					    &pdata->leds[i].name))
> +			pdata->leds[i].name = child->name;
> +		of_property_read_u32(child, "type", &pdata->leds[i].type);
> +		of_property_read_u32(child, "state", &pdata->leds[i].state);
> +		of_property_read_string(child, "linux,default-trigger",
> +					&pdata->leds[i].default_trigger);
> +		if (++i >= maxleds) {
> +			of_node_put(child);
> +			break;
> +		}
> +	}
> +
> +	return pdata;
> +}
> +
>   static int pca9532_probe(struct i2c_client *client,
>   	const struct i2c_device_id *id)
>   {
> +	int devid;
>   	struct pca9532_data *data = i2c_get_clientdata(client);
>   	struct pca9532_platform_data *pca9532_pdata =
>   			dev_get_platdata(&client->dev);
> -
> -	if (!pca9532_pdata)
> -		return -EIO;
> +	struct device_node *np = client->dev.of_node;
> +
> +	if (!pca9532_pdata) {
> +		if (np) {
> +			pca9532_pdata =
> +				pca9532_of_populate_pdata(&client->dev, np);
> +			if (IS_ERR(pca9532_pdata))
> +				return PTR_ERR(pca9532_pdata);
> +		} else {
> +			dev_err(&client->dev, "no platform data\n");
> +			return -EINVAL;
> +		}
> +		devid = (int)of_match_device(
> +			of_pca9532_leds_match, &client->dev)->data;
> +	} else {
> +		devid = id->driver_data;
> +	}
>
>   	if (!i2c_check_functionality(client->adapter,
>   		I2C_FUNC_SMBUS_BYTE_DATA))
> @@ -450,7 +511,7 @@ static int pca9532_probe(struct i2c_client *client,
>   	if (!data)
>   		return -ENOMEM;
>
> -	data->chip_info = &pca9532_chip_info_tbl[id->driver_data];
> +	data->chip_info = &pca9532_chip_info_tbl[devid];
>
>   	dev_info(&client->dev, "setting platform data\n");
>   	i2c_set_clientdata(client, data);
> diff --git a/include/dt-bindings/leds/leds-pca9532.h b/include/dt-bindings/leds/leds-pca9532.h
> new file mode 100644
> index 0000000..4db6cb2
> --- /dev/null
> +++ b/include/dt-bindings/leds/leds-pca9532.h
> @@ -0,0 +1,23 @@
> +/*
> + * This header provides constants for pca9532 LED bindings.
> + *
> + * This file is licensed under the terms of the GNU General Public
> + * License version 2.  This program is licensed "as is" without any
> + * warranty of any kind, whether express or implied.
> + */
> +
> +#ifndef _DT_BINDINGS_LEDS_PCA9532_H
> +#define _DT_BINDINGS_LEDS_PCA9532_H
> +
> +#define PCA9532_OFF               0x0
> +#define PCA9532_ON                0x1
> +#define PCA9532_PWM0              0x2
> +#define PCA9532_PWM1              0x3
> +
> +#define PCA9532_TYPE_NONE         0
> +#define PCA9532_TYPE_LED          1
> +#define PCA9532_TYPE_N2100_BEEP   2
> +#define PCA9532_TYPE_GPIO         3
> +#define PCA9532_LED_TIMER2        4
> +
> +#endif /* _DT_BINDINGS_LEDS_PCA9532_H */
> diff --git a/include/linux/leds-pca9532.h b/include/linux/leds-pca9532.h
> index b8d6fff..562b320 100644
> --- a/include/linux/leds-pca9532.h
> +++ b/include/linux/leds-pca9532.h
> @@ -16,25 +16,17 @@
>
>   #include <linux/leds.h>
>   #include <linux/workqueue.h>
> -
> -enum pca9532_state {
> -	PCA9532_OFF  = 0x0,
> -	PCA9532_ON   = 0x1,
> -	PCA9532_PWM0 = 0x2,
> -	PCA9532_PWM1 = 0x3
> -};
> -
> -enum pca9532_type { PCA9532_TYPE_NONE, PCA9532_TYPE_LED,
> -	PCA9532_TYPE_N2100_BEEP, PCA9532_TYPE_GPIO };
> +#include <dt-bindings/leds/leds-pca9532.h>

Please move this include directive to leds-pca9532.c,
on the top of existing directives, to keep alphabetical order.

>
>   struct pca9532_led {
>   	u8 id;
>   	struct i2c_client *client;
> -	char *name;
> +	const char *name;
> +	const char *default_trigger;
>   	struct led_classdev ldev;
>   	struct work_struct work;
> -	enum pca9532_type type;
> -	enum pca9532_state state;
> +	u32 type;
> +	u32 state;
>   };
>
>   struct pca9532_platform_data {
>


-- 
Best regards,
Jacek Anaszewski