diff mbox

[v5,1/4] leds: netxbig: add device tree binding

Message ID 1442910248-11380-2-git-send-email-simon.guinot@sequanux.org (mailing list archive)
State New, archived
Headers show

Commit Message

Simon Guinot Sept. 22, 2015, 8:24 a.m. UTC
This patch adds device tree support for the netxbig LEDs.

This also introduces a additionnal DT binding for the GPIO extension bus
(netxbig-gpio-ext) used to configure the LEDs. Since this bus could also
be used to control other devices, then it seems more suitable to have it
in a separate DT binding.

Signed-off-by: Simon Guinot <simon.guinot@sequanux.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
---
 .../devicetree/bindings/gpio/netxbig-gpio-ext.txt  |  22 ++
 .../devicetree/bindings/leds/leds-netxbig.txt      |  92 +++++++
 drivers/leds/leds-netxbig.c                        | 265 +++++++++++++++++++--
 include/dt-bindings/leds/leds-netxbig.h            |  18 ++
 .../linux/platform_data/leds-kirkwood-netxbig.h    |   1 +
 5 files changed, 376 insertions(+), 22 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/gpio/netxbig-gpio-ext.txt
 create mode 100644 Documentation/devicetree/bindings/leds/leds-netxbig.txt
 create mode 100644 include/dt-bindings/leds/leds-netxbig.h

Changes for v2:
- Check timer mode value retrieved from DT.
- In netxbig_leds_get_of_pdata, don't use unsigned long variables to get
  timer delay values from DT with function of_property_read_u32_index.
  Instead, use a temporary u32 variable. This allows to silence a static
  checker warning.
- Make timer property optional in the binding documentation. It is now
  aligned with the driver code.

Changes for v3:
- Fix pointer usage with the temporary u32 variable while calling
  of_property_read_u32_index.

Changes for v4:
- In DT binding document netxbig-gpio-ext.txt, detail byte order for
  registers and latch mechanism for "enable-gpio".
- In leds-netxbig.c, add some error messages.
- In leds-netxbig.c, fix some "sizeof" style issues.
- In leds-netxbig.c, in netxbig_leds_get_of_pdata(), move the
  of_property_read_string() calls after the error-prone checks.
- Add some Acked-by.

Changes for v5:
- Rename DT property "bright-max" into the more common "max-brightness".
- Make use of the "max-brightness" DT property. Instead of counting the
  data pins of the GPIO extension bus, use "max-brightness" to get the
  maximum brightness level.

Comments

Jacek Anaszewski Sept. 24, 2015, 12:19 p.m. UTC | #1
Hi Simon,

On 09/22/2015 10:24 AM, Simon Guinot wrote:
> This patch adds device tree support for the netxbig LEDs.
>
> This also introduces a additionnal DT binding for the GPIO extension bus
> (netxbig-gpio-ext) used to configure the LEDs. Since this bus could also
> be used to control other devices, then it seems more suitable to have it
> in a separate DT binding.
>
> Signed-off-by: Simon Guinot <simon.guinot@sequanux.org>
> Acked-by: Linus Walleij <linus.walleij@linaro.org>
> ---
>   .../devicetree/bindings/gpio/netxbig-gpio-ext.txt  |  22 ++
>   .../devicetree/bindings/leds/leds-netxbig.txt      |  92 +++++++
>   drivers/leds/leds-netxbig.c                        | 265 +++++++++++++++++++--
>   include/dt-bindings/leds/leds-netxbig.h            |  18 ++
>   .../linux/platform_data/leds-kirkwood-netxbig.h    |   1 +
>   5 files changed, 376 insertions(+), 22 deletions(-)
>   create mode 100644 Documentation/devicetree/bindings/gpio/netxbig-gpio-ext.txt
>   create mode 100644 Documentation/devicetree/bindings/leds/leds-netxbig.txt
>   create mode 100644 include/dt-bindings/leds/leds-netxbig.h
>
> Changes for v2:
> - Check timer mode value retrieved from DT.
> - In netxbig_leds_get_of_pdata, don't use unsigned long variables to get
>    timer delay values from DT with function of_property_read_u32_index.
>    Instead, use a temporary u32 variable. This allows to silence a static
>    checker warning.
> - Make timer property optional in the binding documentation. It is now
>    aligned with the driver code.
>
> Changes for v3:
> - Fix pointer usage with the temporary u32 variable while calling
>    of_property_read_u32_index.
>
> Changes for v4:
> - In DT binding document netxbig-gpio-ext.txt, detail byte order for
>    registers and latch mechanism for "enable-gpio".
> - In leds-netxbig.c, add some error messages.
> - In leds-netxbig.c, fix some "sizeof" style issues.
> - In leds-netxbig.c, in netxbig_leds_get_of_pdata(), move the
>    of_property_read_string() calls after the error-prone checks.
> - Add some Acked-by.
>
> Changes for v5:
> - Rename DT property "bright-max" into the more common "max-brightness".
> - Make use of the "max-brightness" DT property. Instead of counting the
>    data pins of the GPIO extension bus, use "max-brightness" to get the
>    maximum brightness level.
>
> diff --git a/Documentation/devicetree/bindings/gpio/netxbig-gpio-ext.txt b/Documentation/devicetree/bindings/gpio/netxbig-gpio-ext.txt
> new file mode 100644
> index 000000000000..50ec2e690701
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/gpio/netxbig-gpio-ext.txt
> @@ -0,0 +1,22 @@
> +Binding for the GPIO extension bus found on some LaCie/Seagate boards
> +(Example: 2Big/5Big Network v2, 2Big NAS).
> +
> +Required properties:
> +- compatible: "lacie,netxbig-gpio-ext".
> +- addr-gpios: GPIOs representing the address register (LSB -> MSB).
> +- data-gpios: GPIOs representing the data register (LSB -> MSB).
> +- enable-gpio: latches the new configuration (address, data) on raising edge.
> +
> +Example:
> +
> +netxbig_gpio_ext: netxbig-gpio-ext {
> +	compatible = "lacie,netxbig-gpio-ext";
> +
> +	addr-gpios = <&gpio1 15 GPIO_ACTIVE_HIGH
> +		      &gpio1 16 GPIO_ACTIVE_HIGH
> +		      &gpio1 17 GPIO_ACTIVE_HIGH>;
> +	data-gpios = <&gpio1 12 GPIO_ACTIVE_HIGH
> +		      &gpio1 13 GPIO_ACTIVE_HIGH
> +		      &gpio1 14 GPIO_ACTIVE_HIGH>;
> +	enable-gpio = <&gpio0 29 GPIO_ACTIVE_HIGH>;
> +};
> diff --git a/Documentation/devicetree/bindings/leds/leds-netxbig.txt b/Documentation/devicetree/bindings/leds/leds-netxbig.txt
> new file mode 100644
> index 000000000000..5ef92a26d768
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/leds/leds-netxbig.txt
> @@ -0,0 +1,92 @@
> +Binding for the CPLD LEDs (GPIO extension bus) found on some LaCie/Seagate
> +boards (Example: 2Big/5Big Network v2, 2Big NAS).
> +
> +Required properties:
> +- compatible: "lacie,netxbig-leds".
> +- gpio-ext: Phandle for the gpio-ext bus.
> +
> +Optional properties:
> +- timers: Timer array. Each timer entry is represented by three integers:
> +  Mode (gpio-ext bus), delay_on and delay_off.
> +
> +Each LED is represented as a sub-node of the netxbig-leds device.
> +
> +Required sub-node properties:
> +- mode-addr: Mode register address on gpio-ext bus.
> +- mode-val: Mode to value mapping. Each entry is represented by two integers:
> +  A mode and the corresponding value on the gpio-ext bus.
> +- bright-addr: Brightness register address on gpio-ext bus.
> +- max-brightness: Maximum brightness value.
> +
> +Optional sub-node properties:
> +- label: Name for this LED. If omitted, the label is taken from the node name.
> +- linux,default-trigger: Trigger assigned to the LED.
> +
> +Example:
> +
> +netxbig-leds {
> +	compatible = "lacie,netxbig-leds";
> +
> +	gpio-ext = &gpio_ext;
> +
> +	timers = <NETXBIG_LED_TIMER1 500 500
> +		  NETXBIG_LED_TIMER2 500 1000>;
> +
> +	blue-power {
> +		label = "netxbig:blue:power";
> +		mode-addr = <0>;
> +		mode-val = <NETXBIG_LED_OFF 0
> +			    NETXBIG_LED_ON 1
> +			    NETXBIG_LED_TIMER1 3
> +			    NETXBIG_LED_TIMER2 7>;
> +		bright-addr = <1>;
> +		max-brightness = <7>;
> +	};
> +	red-power {
> +		label = "netxbig:red:power";
> +		mode-addr = <0>;
> +		mode-val = <NETXBIG_LED_OFF 0
> +			    NETXBIG_LED_ON 2
> +			    NETXBIG_LED_TIMER1 4>;
> +		bright-addr = <1>;
> +		max-brightness = <7>;
> +	};
> +	blue-sata0 {
> +		label = "netxbig:blue:sata0";
> +		mode-addr = <3>;
> +		mode-val = <NETXBIG_LED_OFF 0
> +			    NETXBIG_LED_ON 7
> +			    NETXBIG_LED_SATA 1
> +			    NETXBIG_LED_TIMER1 3>;
> +		bright-addr = <2>;
> +		max-brightness = <7>;
> +	};
> +	red-sata0 {
> +		label = "netxbig:red:sata0";
> +		mode-addr = <3>;
> +		mode-val = <NETXBIG_LED_OFF 0
> +			    NETXBIG_LED_ON 2
> +			    NETXBIG_LED_TIMER1 4>;
> +		bright-addr = <2>;
> +		max-brightness = <7>;
> +	};
> +	blue-sata1 {
> +		label = "netxbig:blue:sata1";
> +		mode-addr = <4>;
> +		mode-val = <NETXBIG_LED_OFF 0
> +			    NETXBIG_LED_ON 7
> +			    NETXBIG_LED_SATA 1
> +			    NETXBIG_LED_TIMER1 3>;
> +		bright-addr = <2>;
> +		max-brightness = <7>;
> +	};
> +	red-sata1 {
> +		label = "netxbig:red:sata1";
> +		mode-addr = <4>;
> +		mode-val = <NETXBIG_LED_OFF 0
> +			    NETXBIG_LED_ON 2
> +			    NETXBIG_LED_TIMER1 4>;
> +		bright-addr = <2>;
> +		max-brightness = <7>;
> +	};
> +};
> diff --git a/drivers/leds/leds-netxbig.c b/drivers/leds/leds-netxbig.c
> index 25e419752a7b..19dac94b0364 100644
> --- a/drivers/leds/leds-netxbig.c
> +++ b/drivers/leds/leds-netxbig.c
> @@ -26,6 +26,7 @@
>   #include <linux/spinlock.h>
>   #include <linux/platform_device.h>
>   #include <linux/gpio.h>
> +#include <linux/of_gpio.h>
>   #include <linux/leds.h>
>   #include <linux/platform_data/leds-kirkwood-netxbig.h>
>
> @@ -140,6 +141,11 @@ struct netxbig_led_data {
>   	spinlock_t		lock;
>   };
>
> +struct netxbig_led_priv {
> +	struct netxbig_led_platform_data *pdata;
> +	struct netxbig_led_data leds_data[];
> +};
> +
>   static int netxbig_led_get_timer_mode(enum netxbig_led_mode *mode,
>   				      unsigned long delay_on,
>   				      unsigned long delay_off,
> @@ -304,12 +310,12 @@ static void delete_netxbig_led(struct netxbig_led_data *led_dat)
>   	led_classdev_unregister(&led_dat->cdev);
>   }
>
> -static int
> -create_netxbig_led(struct platform_device *pdev,
> -		   struct netxbig_led_data *led_dat,
> -		   const struct netxbig_led *template)
> +static int create_netxbig_led(struct platform_device *pdev, int led,
> +			      struct netxbig_led_priv *priv)
>   {
> -	struct netxbig_led_platform_data *pdata = dev_get_platdata(&pdev->dev);
> +	struct netxbig_led_platform_data *pdata = priv->pdata;
> +	struct netxbig_led_data *led_dat = &priv->leds_data[led];
> +	const struct netxbig_led *template = &priv->pdata->leds[led];
>
>   	spin_lock_init(&led_dat->lock);
>   	led_dat->gpio_ext = pdata->gpio_ext;
> @@ -333,7 +339,7 @@ create_netxbig_led(struct platform_device *pdev,
>   	led_dat->mode_addr = template->mode_addr;
>   	led_dat->mode_val = template->mode_val;
>   	led_dat->bright_addr = template->bright_addr;
> -	led_dat->bright_max = (1 << pdata->gpio_ext->num_data) - 1;
> +	led_dat->bright_max = template->bright_max;

Could you explain please, why in netxbig_led_set() led_dat->bright_max
is multiplied by the brightness value to be set as shown below?


void netxbig_led_set(struct led_classdev *led_cdev,
                      enum led_brightness value)
{
...
         if (set_brightness) {
                 bright_val = DIV_ROUND_UP(value * led_dat->bright_max,
                                           LED_FULL);
                 gpio_ext_set_value(led_dat->gpio_ext,
                                    led_dat->bright_addr, bright_val);
         }
...
}


>   	led_dat->timer = pdata->timer;
>   	led_dat->num_timer = pdata->num_timer;
>   	/*
> @@ -346,38 +352,254 @@ create_netxbig_led(struct platform_device *pdev,
>   	return led_classdev_register(&pdev->dev, &led_dat->cdev);
>   }
>
> +#ifdef CONFIG_OF_GPIO
> +static int gpio_ext_get_of_pdata(struct device *dev, struct device_node *np,
> +				 struct netxbig_gpio_ext *gpio_ext)
> +{
> +	int *addr, *data;
> +	int num_addr, num_data;
> +	int ret;
> +	int i;
> +
> +	ret = of_gpio_named_count(np, "addr-gpios");
> +	if (ret < 0) {
> +		dev_err(dev,
> +			"Failed to count GPIOs in DT property addr-gpios\n");
> +		return ret;
> +	}
> +	num_addr = ret;
> +	addr = devm_kzalloc(dev, num_addr * sizeof(*addr), GFP_KERNEL);
> +	if (!addr)
> +		return -ENOMEM;
> +
> +	for (i = 0; i < num_addr; i++) {
> +		ret = of_get_named_gpio(np, "addr-gpios", i);
> +		if (ret < 0)
> +			return ret;
> +		addr[i] = ret;
> +	}
> +	gpio_ext->addr = addr;
> +	gpio_ext->num_addr = num_addr;
> +
> +	ret = of_gpio_named_count(np, "data-gpios");
> +	if (ret < 0) {
> +		dev_err(dev,
> +			"Failed to count GPIOs in DT property data-gpios\n");
> +		return ret;
> +	}
> +	num_data = ret;
> +	data = devm_kzalloc(dev, num_data * sizeof(*data), GFP_KERNEL);
> +	if (!data)
> +		return -ENOMEM;
> +
> +	for (i = 0; i < num_data; i++) {
> +		ret = of_get_named_gpio(np, "data-gpios", i);
> +		if (ret < 0)
> +			return ret;
> +		data[i] = ret;
> +	}
> +	gpio_ext->data = data;
> +	gpio_ext->num_data = num_data;
> +
> +	ret = of_get_named_gpio(np, "enable-gpio", 0);
> +	if (ret < 0) {
> +		dev_err(dev,
> +			"Failed to get GPIO from DT property enable-gpio\n");
> +		return ret;
> +	}
> +	gpio_ext->enable = ret;
> +
> +	return 0;
> +}
> +
> +static int netxbig_leds_get_of_pdata(struct device *dev,
> +				     struct netxbig_led_platform_data *pdata)
> +{
> +	struct device_node *np = dev->of_node;
> +	struct device_node *gpio_ext_np;
> +	struct device_node *child;
> +	struct netxbig_gpio_ext *gpio_ext;
> +	struct netxbig_led_timer *timers;
> +	struct netxbig_led *leds, *led;
> +	int num_timers;
> +	int num_leds = 0;
> +	int ret;
> +	int i;
> +
> +	/* GPIO extension */
> +	gpio_ext_np = of_parse_phandle(np, "gpio-ext", 0);
> +	if (!gpio_ext_np) {
> +		dev_err(dev, "Failed to get DT handle gpio-ext\n");
> +		return -EINVAL;
> +	}
> +
> +	gpio_ext = devm_kzalloc(dev, sizeof(*gpio_ext), GFP_KERNEL);
> +	if (!gpio_ext)
> +		return -ENOMEM;
> +	ret = gpio_ext_get_of_pdata(dev, gpio_ext_np, gpio_ext);
> +	if (ret)
> +		return ret;
> +	of_node_put(gpio_ext_np);
> +	pdata->gpio_ext = gpio_ext;
> +
> +	/* Timers (optional) */
> +	ret = of_property_count_u32_elems(np, "timers");
> +	if (ret > 0) {
> +		if (ret % 3)
> +			return -EINVAL;
> +		num_timers = ret / 3;
> +		timers = devm_kzalloc(dev, num_timers * sizeof(*timers),
> +				      GFP_KERNEL);
> +		if (!timers)
> +			return -ENOMEM;
> +		for (i = 0; i < num_timers; i++) {
> +			u32 tmp;
> +
> +			of_property_read_u32_index(np, "timers", 3 * i,
> +						   &timers[i].mode);
> +			if (timers[i].mode >= NETXBIG_LED_MODE_NUM)
> +				return -EINVAL;
> +			of_property_read_u32_index(np, "timers",
> +						   3 * i + 1, &tmp);
> +			timers[i].delay_on = tmp;
> +			of_property_read_u32_index(np, "timers",
> +						   3 * i + 2, &tmp);
> +			timers[i].delay_off = tmp;
> +		}
> +		pdata->timer = timers;
> +		pdata->num_timer = num_timers;
> +	}
> +
> +	/* LEDs */
> +	num_leds = of_get_child_count(np);
> +	if (!num_leds) {
> +		dev_err(dev, "No LED subnodes found in DT\n");
> +		return -ENODEV;
> +	}
> +
> +	leds = devm_kzalloc(dev, num_leds * sizeof(*leds), GFP_KERNEL);
> +	if (!leds)
> +		return -ENOMEM;
> +
> +	led = leds;
> +	for_each_child_of_node(np, child) {
> +		const char *string;
> +		int *mode_val;
> +		int num_modes;
> +
> +		if (of_property_read_u32(child, "mode-addr",
> +					 &led->mode_addr))
> +			return -EINVAL;

Since for_each_child_of_node uses of_get_next_child underneath,
the user is responsible for releasing current child in case
they are going to break the iteration. In other words you
need to execute of_node_put(child) then. Assigning error codes
to ret and following it with "goto exit_for_each" would do here,
where exit_for_each is defined as follows:

exit_for_each:
	of_node_put(child);
	return ret;


> +
> +		if (of_property_read_u32(child, "bright-addr",
> +					 &led->bright_addr))
> +			return -EINVAL;
> +
> +		if (of_property_read_u32(child, "max-brightness",
> +					 &led->bright_max))
> +			return -EINVAL;
> +		mode_val =
> +			devm_kzalloc(dev,
> +				     NETXBIG_LED_MODE_NUM * sizeof(*mode_val),
> +				     GFP_KERNEL);
> +		if (!mode_val)
> +			return -ENOMEM;
> +
> +		for (i = 0; i < NETXBIG_LED_MODE_NUM; i++)
> +			mode_val[i] = NETXBIG_LED_INVALID_MODE;
> +
> +		ret = of_property_count_u32_elems(child, "mode-val");
> +		if (ret < 0 || ret % 2)
> +			return -EINVAL;
> +		num_modes = ret / 2;
> +		if (num_modes > NETXBIG_LED_MODE_NUM)
> +			return -EINVAL;
> +
> +		for (i = 0; i < num_modes; i++) {
> +			int mode;
> +			int val;
> +
> +			of_property_read_u32_index(child,
> +						   "mode-val", 2 * i, &mode);
> +			of_property_read_u32_index(child,
> +						   "mode-val", 2 * i + 1, &val);
> +			if (mode >= NETXBIG_LED_MODE_NUM)
> +				return -EINVAL;
> +			mode_val[mode] = val;
> +		}
> +		led->mode_val = mode_val;
> +
> +		if (!of_property_read_string(child, "label", &string))
> +			led->name = string;
> +		else
> +			led->name = child->name;
> +
> +		if (!of_property_read_string(child,
> +					     "linux,default-trigger", &string))
> +			led->default_trigger = string;
> +
> +		led++;
> +	}
> +
> +	pdata->leds = leds;
> +	pdata->num_leds = num_leds;
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id of_netxbig_leds_match[] = {
> +	{ .compatible = "lacie,netxbig-leds", },
> +	{},
> +};
> +#else
> +static inline int
> +netxbig_leds_get_of_pdata(struct device *dev,
> +			  struct netxbig_led_platform_data *pdata)
> +{
> +	return -ENODEV;
> +}
> +#endif /* CONFIG_OF_GPIO */
> +
>   static int netxbig_led_probe(struct platform_device *pdev)
>   {
>   	struct netxbig_led_platform_data *pdata = dev_get_platdata(&pdev->dev);
> -	struct netxbig_led_data *leds_data;
> +	struct netxbig_led_priv *priv;
>   	int i;
>   	int ret;
>
> -	if (!pdata)
> -		return -EINVAL;
> +	if (!pdata) {
> +		pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
> +		if (!pdata)
> +			return -ENOMEM;
> +		ret = netxbig_leds_get_of_pdata(&pdev->dev, pdata);
> +		if (ret)
> +			return ret;
> +	}
>
> -	leds_data = devm_kzalloc(&pdev->dev,
> -		sizeof(struct netxbig_led_data) * pdata->num_leds, GFP_KERNEL);
> -	if (!leds_data)
> +	priv = devm_kzalloc(&pdev->dev, sizeof(*priv) +
> +			    pdata->num_leds * sizeof(struct netxbig_led_data),
> +			    GFP_KERNEL);
> +	if (!priv)
>   		return -ENOMEM;
> +	priv->pdata = pdata;
>
>   	ret = gpio_ext_init(pdata->gpio_ext);
>   	if (ret < 0)
>   		return ret;
>
>   	for (i = 0; i < pdata->num_leds; i++) {
> -		ret = create_netxbig_led(pdev, &leds_data[i], &pdata->leds[i]);
> +		ret = create_netxbig_led(pdev, i, priv);
>   		if (ret < 0)
>   			goto err_free_leds;
>   	}
> -
> -	platform_set_drvdata(pdev, leds_data);
> +	platform_set_drvdata(pdev, priv);
>
>   	return 0;
>
>   err_free_leds:
>   	for (i = i - 1; i >= 0; i--)
> -		delete_netxbig_led(&leds_data[i]);
> +		delete_netxbig_led(&priv->leds_data[i]);
>
>   	gpio_ext_free(pdata->gpio_ext);
>   	return ret;
> @@ -385,14 +607,12 @@ err_free_leds:
>
>   static int netxbig_led_remove(struct platform_device *pdev)
>   {
> -	struct netxbig_led_platform_data *pdata = dev_get_platdata(&pdev->dev);
> -	struct netxbig_led_data *leds_data;
> +	struct netxbig_led_priv *priv = platform_get_drvdata(pdev);
> +	struct netxbig_led_platform_data *pdata = priv->pdata;
>   	int i;
>
> -	leds_data = platform_get_drvdata(pdev);
> -
>   	for (i = 0; i < pdata->num_leds; i++)
> -		delete_netxbig_led(&leds_data[i]);
> +		delete_netxbig_led(&priv->leds_data[i]);
>
>   	gpio_ext_free(pdata->gpio_ext);
>
> @@ -403,7 +623,8 @@ static struct platform_driver netxbig_led_driver = {
>   	.probe		= netxbig_led_probe,
>   	.remove		= netxbig_led_remove,
>   	.driver		= {
> -		.name	= "leds-netxbig",
> +		.name		= "leds-netxbig",
> +		.of_match_table	= of_match_ptr(of_netxbig_leds_match),
>   	},
>   };
>
> diff --git a/include/dt-bindings/leds/leds-netxbig.h b/include/dt-bindings/leds/leds-netxbig.h
> new file mode 100644
> index 000000000000..92658b0310b2
> --- /dev/null
> +++ b/include/dt-bindings/leds/leds-netxbig.h
> @@ -0,0 +1,18 @@
> +/*
> + * This header provides constants for netxbig 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_NETXBIG_H
> +#define _DT_BINDINGS_LEDS_NETXBIG_H
> +
> +#define NETXBIG_LED_OFF		0
> +#define NETXBIG_LED_ON		1
> +#define NETXBIG_LED_SATA	2
> +#define NETXBIG_LED_TIMER1	3
> +#define NETXBIG_LED_TIMER2	4
> +
> +#endif /* _DT_BINDINGS_LEDS_NETXBIG_H */
> diff --git a/include/linux/platform_data/leds-kirkwood-netxbig.h b/include/linux/platform_data/leds-kirkwood-netxbig.h
> index d2be19a51acd..3c85a735c380 100644
> --- a/include/linux/platform_data/leds-kirkwood-netxbig.h
> +++ b/include/linux/platform_data/leds-kirkwood-netxbig.h
> @@ -40,6 +40,7 @@ struct netxbig_led {
>   	int		mode_addr;
>   	int		*mode_val;
>   	int		bright_addr;
> +	int		bright_max;
>   };
>
>   struct netxbig_led_platform_data {
>
Simon Guinot Sept. 24, 2015, 1:32 p.m. UTC | #2
On Thu, Sep 24, 2015 at 02:19:56PM +0200, Jacek Anaszewski wrote:
> Hi Simon,

Hi Jacek,

Thanks again for the review. Please see my comments below.

> 
> On 09/22/2015 10:24 AM, Simon Guinot wrote:
> >This patch adds device tree support for the netxbig LEDs.
> >
> >This also introduces a additionnal DT binding for the GPIO extension bus
> >(netxbig-gpio-ext) used to configure the LEDs. Since this bus could also
> >be used to control other devices, then it seems more suitable to have it
> >in a separate DT binding.
> >
> >Signed-off-by: Simon Guinot <simon.guinot@sequanux.org>
> >Acked-by: Linus Walleij <linus.walleij@linaro.org>
> >---
> >  .../devicetree/bindings/gpio/netxbig-gpio-ext.txt  |  22 ++
> >  .../devicetree/bindings/leds/leds-netxbig.txt      |  92 +++++++
> >  drivers/leds/leds-netxbig.c                        | 265 +++++++++++++++++++--
> >  include/dt-bindings/leds/leds-netxbig.h            |  18 ++
> >  .../linux/platform_data/leds-kirkwood-netxbig.h    |   1 +
> >  5 files changed, 376 insertions(+), 22 deletions(-)
> >  create mode 100644 Documentation/devicetree/bindings/gpio/netxbig-gpio-ext.txt
> >  create mode 100644 Documentation/devicetree/bindings/leds/leds-netxbig.txt
> >  create mode 100644 include/dt-bindings/leds/leds-netxbig.h
> >
> >Changes for v2:
> >- Check timer mode value retrieved from DT.
> >- In netxbig_leds_get_of_pdata, don't use unsigned long variables to get
> >   timer delay values from DT with function of_property_read_u32_index.
> >   Instead, use a temporary u32 variable. This allows to silence a static
> >   checker warning.
> >- Make timer property optional in the binding documentation. It is now
> >   aligned with the driver code.
> >
> >Changes for v3:
> >- Fix pointer usage with the temporary u32 variable while calling
> >   of_property_read_u32_index.
> >
> >Changes for v4:
> >- In DT binding document netxbig-gpio-ext.txt, detail byte order for
> >   registers and latch mechanism for "enable-gpio".
> >- In leds-netxbig.c, add some error messages.
> >- In leds-netxbig.c, fix some "sizeof" style issues.
> >- In leds-netxbig.c, in netxbig_leds_get_of_pdata(), move the
> >   of_property_read_string() calls after the error-prone checks.
> >- Add some Acked-by.
> >
> >Changes for v5:
> >- Rename DT property "bright-max" into the more common "max-brightness".
> >- Make use of the "max-brightness" DT property. Instead of counting the
> >   data pins of the GPIO extension bus, use "max-brightness" to get the
> >   maximum brightness level.

...

> >@@ -333,7 +339,7 @@ create_netxbig_led(struct platform_device *pdev,
> >  	led_dat->mode_addr = template->mode_addr;
> >  	led_dat->mode_val = template->mode_val;
> >  	led_dat->bright_addr = template->bright_addr;
> >-	led_dat->bright_max = (1 << pdata->gpio_ext->num_data) - 1;
> >+	led_dat->bright_max = template->bright_max;
> 
> Could you explain please, why in netxbig_led_set() led_dat->bright_max
> is multiplied by the brightness value to be set as shown below?
> 
> 
> void netxbig_led_set(struct led_classdev *led_cdev,
>                      enum led_brightness value)
> {
> ...
>         if (set_brightness) {
>                 bright_val = DIV_ROUND_UP(value * led_dat->bright_max,
>                                           LED_FULL);
>                 gpio_ext_set_value(led_dat->gpio_ext,
>                                    led_dat->bright_addr, bright_val);
>         }
> ...
> }

Hardware values for brightness levels are in a range 0 to bright_max
(with bright_max = 7).
Software values for brightness levels are in a range 0 to 255.

Here, we are simply converting a software brightness value into an
hardware one. And the resulting value can be written directly into the
CPLD hardware bright register via the gpio-ext bus.

> >+	led = leds;
> >+	for_each_child_of_node(np, child) {
> >+		const char *string;
> >+		int *mode_val;
> >+		int num_modes;
> >+
> >+		if (of_property_read_u32(child, "mode-addr",
> >+					 &led->mode_addr))
> >+			return -EINVAL;
> 
> Since for_each_child_of_node uses of_get_next_child underneath,
> the user is responsible for releasing current child in case
> they are going to break the iteration. In other words you
> need to execute of_node_put(child) then. Assigning error codes
> to ret and following it with "goto exit_for_each" would do here,
> where exit_for_each is defined as follows:
> 
> exit_for_each:
> 	of_node_put(child);
> 	return ret;

OK, good caught. I'll do that for the next version. Note that a bunch of
other LED drivers are needing a such fix too.

Thanks,

Simon
Jacek Anaszewski Sept. 24, 2015, 8:57 p.m. UTC | #3
Hi Simon,

On 09/24/2015 03:32 PM, Simon Guinot wrote:
> On Thu, Sep 24, 2015 at 02:19:56PM +0200, Jacek Anaszewski wrote:
>> Hi Simon,
>
> Hi Jacek,
>
> Thanks again for the review. Please see my comments below.
>
>>
>> On 09/22/2015 10:24 AM, Simon Guinot wrote:
>>> This patch adds device tree support for the netxbig LEDs.
>>>
>>> This also introduces a additionnal DT binding for the GPIO extension bus
>>> (netxbig-gpio-ext) used to configure the LEDs. Since this bus could also
>>> be used to control other devices, then it seems more suitable to have it
>>> in a separate DT binding.
>>>
>>> Signed-off-by: Simon Guinot <simon.guinot@sequanux.org>
>>> Acked-by: Linus Walleij <linus.walleij@linaro.org>
>>> ---
>>>   .../devicetree/bindings/gpio/netxbig-gpio-ext.txt  |  22 ++
>>>   .../devicetree/bindings/leds/leds-netxbig.txt      |  92 +++++++
>>>   drivers/leds/leds-netxbig.c                        | 265 +++++++++++++++++++--
>>>   include/dt-bindings/leds/leds-netxbig.h            |  18 ++
>>>   .../linux/platform_data/leds-kirkwood-netxbig.h    |   1 +
>>>   5 files changed, 376 insertions(+), 22 deletions(-)
>>>   create mode 100644 Documentation/devicetree/bindings/gpio/netxbig-gpio-ext.txt
>>>   create mode 100644 Documentation/devicetree/bindings/leds/leds-netxbig.txt
>>>   create mode 100644 include/dt-bindings/leds/leds-netxbig.h
>>>
>>> Changes for v2:
>>> - Check timer mode value retrieved from DT.
>>> - In netxbig_leds_get_of_pdata, don't use unsigned long variables to get
>>>    timer delay values from DT with function of_property_read_u32_index.
>>>    Instead, use a temporary u32 variable. This allows to silence a static
>>>    checker warning.
>>> - Make timer property optional in the binding documentation. It is now
>>>    aligned with the driver code.
>>>
>>> Changes for v3:
>>> - Fix pointer usage with the temporary u32 variable while calling
>>>    of_property_read_u32_index.
>>>
>>> Changes for v4:
>>> - In DT binding document netxbig-gpio-ext.txt, detail byte order for
>>>    registers and latch mechanism for "enable-gpio".
>>> - In leds-netxbig.c, add some error messages.
>>> - In leds-netxbig.c, fix some "sizeof" style issues.
>>> - In leds-netxbig.c, in netxbig_leds_get_of_pdata(), move the
>>>    of_property_read_string() calls after the error-prone checks.
>>> - Add some Acked-by.
>>>
>>> Changes for v5:
>>> - Rename DT property "bright-max" into the more common "max-brightness".
>>> - Make use of the "max-brightness" DT property. Instead of counting the
>>>    data pins of the GPIO extension bus, use "max-brightness" to get the
>>>    maximum brightness level.
>
> ...
>
>>> @@ -333,7 +339,7 @@ create_netxbig_led(struct platform_device *pdev,
>>>   	led_dat->mode_addr = template->mode_addr;
>>>   	led_dat->mode_val = template->mode_val;
>>>   	led_dat->bright_addr = template->bright_addr;
>>> -	led_dat->bright_max = (1 << pdata->gpio_ext->num_data) - 1;
>>> +	led_dat->bright_max = template->bright_max;
>>
>> Could you explain please, why in netxbig_led_set() led_dat->bright_max
>> is multiplied by the brightness value to be set as shown below?
>>
>>
>> void netxbig_led_set(struct led_classdev *led_cdev,
>>                       enum led_brightness value)
>> {
>> ...
>>          if (set_brightness) {
>>                  bright_val = DIV_ROUND_UP(value * led_dat->bright_max,
>>                                            LED_FULL);
>>                  gpio_ext_set_value(led_dat->gpio_ext,
>>                                     led_dat->bright_addr, bright_val);
>>          }
>> ...
>> }
>
> Hardware values for brightness levels are in a range 0 to bright_max
> (with bright_max = 7).
> Software values for brightness levels are in a range 0 to 255.
>
> Here, we are simply converting a software brightness value into an
> hardware one. And the resulting value can be written directly into the
> CPLD hardware bright register via the gpio-ext bus.

This conversion isn't required, as max_brightness property was
introduced to allow overriding LED_FULL value. I know that this is
in this form for a long time in this driver, just aside note.

>>> +	led = leds;
>>> +	for_each_child_of_node(np, child) {
>>> +		const char *string;
>>> +		int *mode_val;
>>> +		int num_modes;
>>> +
>>> +		if (of_property_read_u32(child, "mode-addr",
>>> +					 &led->mode_addr))
>>> +			return -EINVAL;
>>
>> Since for_each_child_of_node uses of_get_next_child underneath,
>> the user is responsible for releasing current child in case
>> they are going to break the iteration. In other words you
>> need to execute of_node_put(child) then. Assigning error codes
>> to ret and following it with "goto exit_for_each" would do here,
>> where exit_for_each is defined as follows:
>>
>> exit_for_each:
>> 	of_node_put(child);
>> 	return ret;
>
> OK, good caught. I'll do that for the next version. Note that a bunch of
> other LED drivers are needing a such fix too.

Right, but this is not an urgent issue since AFAICT no LED class driver
depends on CONFIG_OF_DYNAMIC, which turns of node ref counting on.
Nonetheless it shouldn't discourage us from producing new code free
of the potential issues, we are aware of.
diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/gpio/netxbig-gpio-ext.txt b/Documentation/devicetree/bindings/gpio/netxbig-gpio-ext.txt
new file mode 100644
index 000000000000..50ec2e690701
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/netxbig-gpio-ext.txt
@@ -0,0 +1,22 @@ 
+Binding for the GPIO extension bus found on some LaCie/Seagate boards
+(Example: 2Big/5Big Network v2, 2Big NAS).
+
+Required properties:
+- compatible: "lacie,netxbig-gpio-ext".
+- addr-gpios: GPIOs representing the address register (LSB -> MSB).
+- data-gpios: GPIOs representing the data register (LSB -> MSB).
+- enable-gpio: latches the new configuration (address, data) on raising edge.
+
+Example:
+
+netxbig_gpio_ext: netxbig-gpio-ext {
+	compatible = "lacie,netxbig-gpio-ext";
+
+	addr-gpios = <&gpio1 15 GPIO_ACTIVE_HIGH
+		      &gpio1 16 GPIO_ACTIVE_HIGH
+		      &gpio1 17 GPIO_ACTIVE_HIGH>;
+	data-gpios = <&gpio1 12 GPIO_ACTIVE_HIGH
+		      &gpio1 13 GPIO_ACTIVE_HIGH
+		      &gpio1 14 GPIO_ACTIVE_HIGH>;
+	enable-gpio = <&gpio0 29 GPIO_ACTIVE_HIGH>;
+};
diff --git a/Documentation/devicetree/bindings/leds/leds-netxbig.txt b/Documentation/devicetree/bindings/leds/leds-netxbig.txt
new file mode 100644
index 000000000000..5ef92a26d768
--- /dev/null
+++ b/Documentation/devicetree/bindings/leds/leds-netxbig.txt
@@ -0,0 +1,92 @@ 
+Binding for the CPLD LEDs (GPIO extension bus) found on some LaCie/Seagate
+boards (Example: 2Big/5Big Network v2, 2Big NAS).
+
+Required properties:
+- compatible: "lacie,netxbig-leds".
+- gpio-ext: Phandle for the gpio-ext bus.
+
+Optional properties:
+- timers: Timer array. Each timer entry is represented by three integers:
+  Mode (gpio-ext bus), delay_on and delay_off.
+
+Each LED is represented as a sub-node of the netxbig-leds device.
+
+Required sub-node properties:
+- mode-addr: Mode register address on gpio-ext bus.
+- mode-val: Mode to value mapping. Each entry is represented by two integers:
+  A mode and the corresponding value on the gpio-ext bus.
+- bright-addr: Brightness register address on gpio-ext bus.
+- max-brightness: Maximum brightness value.
+
+Optional sub-node properties:
+- label: Name for this LED. If omitted, the label is taken from the node name.
+- linux,default-trigger: Trigger assigned to the LED.
+
+Example:
+
+netxbig-leds {
+	compatible = "lacie,netxbig-leds";
+
+	gpio-ext = &gpio_ext;
+
+	timers = <NETXBIG_LED_TIMER1 500 500
+		  NETXBIG_LED_TIMER2 500 1000>;
+
+	blue-power {
+		label = "netxbig:blue:power";
+		mode-addr = <0>;
+		mode-val = <NETXBIG_LED_OFF 0
+			    NETXBIG_LED_ON 1
+			    NETXBIG_LED_TIMER1 3
+			    NETXBIG_LED_TIMER2 7>;
+		bright-addr = <1>;
+		max-brightness = <7>;
+	};
+	red-power {
+		label = "netxbig:red:power";
+		mode-addr = <0>;
+		mode-val = <NETXBIG_LED_OFF 0
+			    NETXBIG_LED_ON 2
+			    NETXBIG_LED_TIMER1 4>;
+		bright-addr = <1>;
+		max-brightness = <7>;
+	};
+	blue-sata0 {
+		label = "netxbig:blue:sata0";
+		mode-addr = <3>;
+		mode-val = <NETXBIG_LED_OFF 0
+			    NETXBIG_LED_ON 7
+			    NETXBIG_LED_SATA 1
+			    NETXBIG_LED_TIMER1 3>;
+		bright-addr = <2>;
+		max-brightness = <7>;
+	};
+	red-sata0 {
+		label = "netxbig:red:sata0";
+		mode-addr = <3>;
+		mode-val = <NETXBIG_LED_OFF 0
+			    NETXBIG_LED_ON 2
+			    NETXBIG_LED_TIMER1 4>;
+		bright-addr = <2>;
+		max-brightness = <7>;
+	};
+	blue-sata1 {
+		label = "netxbig:blue:sata1";
+		mode-addr = <4>;
+		mode-val = <NETXBIG_LED_OFF 0
+			    NETXBIG_LED_ON 7
+			    NETXBIG_LED_SATA 1
+			    NETXBIG_LED_TIMER1 3>;
+		bright-addr = <2>;
+		max-brightness = <7>;
+	};
+	red-sata1 {
+		label = "netxbig:red:sata1";
+		mode-addr = <4>;
+		mode-val = <NETXBIG_LED_OFF 0
+			    NETXBIG_LED_ON 2
+			    NETXBIG_LED_TIMER1 4>;
+		bright-addr = <2>;
+		max-brightness = <7>;
+	};
+};
diff --git a/drivers/leds/leds-netxbig.c b/drivers/leds/leds-netxbig.c
index 25e419752a7b..19dac94b0364 100644
--- a/drivers/leds/leds-netxbig.c
+++ b/drivers/leds/leds-netxbig.c
@@ -26,6 +26,7 @@ 
 #include <linux/spinlock.h>
 #include <linux/platform_device.h>
 #include <linux/gpio.h>
+#include <linux/of_gpio.h>
 #include <linux/leds.h>
 #include <linux/platform_data/leds-kirkwood-netxbig.h>
 
@@ -140,6 +141,11 @@  struct netxbig_led_data {
 	spinlock_t		lock;
 };
 
+struct netxbig_led_priv {
+	struct netxbig_led_platform_data *pdata;
+	struct netxbig_led_data leds_data[];
+};
+
 static int netxbig_led_get_timer_mode(enum netxbig_led_mode *mode,
 				      unsigned long delay_on,
 				      unsigned long delay_off,
@@ -304,12 +310,12 @@  static void delete_netxbig_led(struct netxbig_led_data *led_dat)
 	led_classdev_unregister(&led_dat->cdev);
 }
 
-static int
-create_netxbig_led(struct platform_device *pdev,
-		   struct netxbig_led_data *led_dat,
-		   const struct netxbig_led *template)
+static int create_netxbig_led(struct platform_device *pdev, int led,
+			      struct netxbig_led_priv *priv)
 {
-	struct netxbig_led_platform_data *pdata = dev_get_platdata(&pdev->dev);
+	struct netxbig_led_platform_data *pdata = priv->pdata;
+	struct netxbig_led_data *led_dat = &priv->leds_data[led];
+	const struct netxbig_led *template = &priv->pdata->leds[led];
 
 	spin_lock_init(&led_dat->lock);
 	led_dat->gpio_ext = pdata->gpio_ext;
@@ -333,7 +339,7 @@  create_netxbig_led(struct platform_device *pdev,
 	led_dat->mode_addr = template->mode_addr;
 	led_dat->mode_val = template->mode_val;
 	led_dat->bright_addr = template->bright_addr;
-	led_dat->bright_max = (1 << pdata->gpio_ext->num_data) - 1;
+	led_dat->bright_max = template->bright_max;
 	led_dat->timer = pdata->timer;
 	led_dat->num_timer = pdata->num_timer;
 	/*
@@ -346,38 +352,254 @@  create_netxbig_led(struct platform_device *pdev,
 	return led_classdev_register(&pdev->dev, &led_dat->cdev);
 }
 
+#ifdef CONFIG_OF_GPIO
+static int gpio_ext_get_of_pdata(struct device *dev, struct device_node *np,
+				 struct netxbig_gpio_ext *gpio_ext)
+{
+	int *addr, *data;
+	int num_addr, num_data;
+	int ret;
+	int i;
+
+	ret = of_gpio_named_count(np, "addr-gpios");
+	if (ret < 0) {
+		dev_err(dev,
+			"Failed to count GPIOs in DT property addr-gpios\n");
+		return ret;
+	}
+	num_addr = ret;
+	addr = devm_kzalloc(dev, num_addr * sizeof(*addr), GFP_KERNEL);
+	if (!addr)
+		return -ENOMEM;
+
+	for (i = 0; i < num_addr; i++) {
+		ret = of_get_named_gpio(np, "addr-gpios", i);
+		if (ret < 0)
+			return ret;
+		addr[i] = ret;
+	}
+	gpio_ext->addr = addr;
+	gpio_ext->num_addr = num_addr;
+
+	ret = of_gpio_named_count(np, "data-gpios");
+	if (ret < 0) {
+		dev_err(dev,
+			"Failed to count GPIOs in DT property data-gpios\n");
+		return ret;
+	}
+	num_data = ret;
+	data = devm_kzalloc(dev, num_data * sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	for (i = 0; i < num_data; i++) {
+		ret = of_get_named_gpio(np, "data-gpios", i);
+		if (ret < 0)
+			return ret;
+		data[i] = ret;
+	}
+	gpio_ext->data = data;
+	gpio_ext->num_data = num_data;
+
+	ret = of_get_named_gpio(np, "enable-gpio", 0);
+	if (ret < 0) {
+		dev_err(dev,
+			"Failed to get GPIO from DT property enable-gpio\n");
+		return ret;
+	}
+	gpio_ext->enable = ret;
+
+	return 0;
+}
+
+static int netxbig_leds_get_of_pdata(struct device *dev,
+				     struct netxbig_led_platform_data *pdata)
+{
+	struct device_node *np = dev->of_node;
+	struct device_node *gpio_ext_np;
+	struct device_node *child;
+	struct netxbig_gpio_ext *gpio_ext;
+	struct netxbig_led_timer *timers;
+	struct netxbig_led *leds, *led;
+	int num_timers;
+	int num_leds = 0;
+	int ret;
+	int i;
+
+	/* GPIO extension */
+	gpio_ext_np = of_parse_phandle(np, "gpio-ext", 0);
+	if (!gpio_ext_np) {
+		dev_err(dev, "Failed to get DT handle gpio-ext\n");
+		return -EINVAL;
+	}
+
+	gpio_ext = devm_kzalloc(dev, sizeof(*gpio_ext), GFP_KERNEL);
+	if (!gpio_ext)
+		return -ENOMEM;
+	ret = gpio_ext_get_of_pdata(dev, gpio_ext_np, gpio_ext);
+	if (ret)
+		return ret;
+	of_node_put(gpio_ext_np);
+	pdata->gpio_ext = gpio_ext;
+
+	/* Timers (optional) */
+	ret = of_property_count_u32_elems(np, "timers");
+	if (ret > 0) {
+		if (ret % 3)
+			return -EINVAL;
+		num_timers = ret / 3;
+		timers = devm_kzalloc(dev, num_timers * sizeof(*timers),
+				      GFP_KERNEL);
+		if (!timers)
+			return -ENOMEM;
+		for (i = 0; i < num_timers; i++) {
+			u32 tmp;
+
+			of_property_read_u32_index(np, "timers", 3 * i,
+						   &timers[i].mode);
+			if (timers[i].mode >= NETXBIG_LED_MODE_NUM)
+				return -EINVAL;
+			of_property_read_u32_index(np, "timers",
+						   3 * i + 1, &tmp);
+			timers[i].delay_on = tmp;
+			of_property_read_u32_index(np, "timers",
+						   3 * i + 2, &tmp);
+			timers[i].delay_off = tmp;
+		}
+		pdata->timer = timers;
+		pdata->num_timer = num_timers;
+	}
+
+	/* LEDs */
+	num_leds = of_get_child_count(np);
+	if (!num_leds) {
+		dev_err(dev, "No LED subnodes found in DT\n");
+		return -ENODEV;
+	}
+
+	leds = devm_kzalloc(dev, num_leds * sizeof(*leds), GFP_KERNEL);
+	if (!leds)
+		return -ENOMEM;
+
+	led = leds;
+	for_each_child_of_node(np, child) {
+		const char *string;
+		int *mode_val;
+		int num_modes;
+
+		if (of_property_read_u32(child, "mode-addr",
+					 &led->mode_addr))
+			return -EINVAL;
+
+		if (of_property_read_u32(child, "bright-addr",
+					 &led->bright_addr))
+			return -EINVAL;
+
+		if (of_property_read_u32(child, "max-brightness",
+					 &led->bright_max))
+			return -EINVAL;
+
+		mode_val =
+			devm_kzalloc(dev,
+				     NETXBIG_LED_MODE_NUM * sizeof(*mode_val),
+				     GFP_KERNEL);
+		if (!mode_val)
+			return -ENOMEM;
+
+		for (i = 0; i < NETXBIG_LED_MODE_NUM; i++)
+			mode_val[i] = NETXBIG_LED_INVALID_MODE;
+
+		ret = of_property_count_u32_elems(child, "mode-val");
+		if (ret < 0 || ret % 2)
+			return -EINVAL;
+		num_modes = ret / 2;
+		if (num_modes > NETXBIG_LED_MODE_NUM)
+			return -EINVAL;
+
+		for (i = 0; i < num_modes; i++) {
+			int mode;
+			int val;
+
+			of_property_read_u32_index(child,
+						   "mode-val", 2 * i, &mode);
+			of_property_read_u32_index(child,
+						   "mode-val", 2 * i + 1, &val);
+			if (mode >= NETXBIG_LED_MODE_NUM)
+				return -EINVAL;
+			mode_val[mode] = val;
+		}
+		led->mode_val = mode_val;
+
+		if (!of_property_read_string(child, "label", &string))
+			led->name = string;
+		else
+			led->name = child->name;
+
+		if (!of_property_read_string(child,
+					     "linux,default-trigger", &string))
+			led->default_trigger = string;
+
+		led++;
+	}
+
+	pdata->leds = leds;
+	pdata->num_leds = num_leds;
+
+	return 0;
+}
+
+static const struct of_device_id of_netxbig_leds_match[] = {
+	{ .compatible = "lacie,netxbig-leds", },
+	{},
+};
+#else
+static inline int
+netxbig_leds_get_of_pdata(struct device *dev,
+			  struct netxbig_led_platform_data *pdata)
+{
+	return -ENODEV;
+}
+#endif /* CONFIG_OF_GPIO */
+
 static int netxbig_led_probe(struct platform_device *pdev)
 {
 	struct netxbig_led_platform_data *pdata = dev_get_platdata(&pdev->dev);
-	struct netxbig_led_data *leds_data;
+	struct netxbig_led_priv *priv;
 	int i;
 	int ret;
 
-	if (!pdata)
-		return -EINVAL;
+	if (!pdata) {
+		pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
+		if (!pdata)
+			return -ENOMEM;
+		ret = netxbig_leds_get_of_pdata(&pdev->dev, pdata);
+		if (ret)
+			return ret;
+	}
 
-	leds_data = devm_kzalloc(&pdev->dev,
-		sizeof(struct netxbig_led_data) * pdata->num_leds, GFP_KERNEL);
-	if (!leds_data)
+	priv = devm_kzalloc(&pdev->dev, sizeof(*priv) +
+			    pdata->num_leds * sizeof(struct netxbig_led_data),
+			    GFP_KERNEL);
+	if (!priv)
 		return -ENOMEM;
+	priv->pdata = pdata;
 
 	ret = gpio_ext_init(pdata->gpio_ext);
 	if (ret < 0)
 		return ret;
 
 	for (i = 0; i < pdata->num_leds; i++) {
-		ret = create_netxbig_led(pdev, &leds_data[i], &pdata->leds[i]);
+		ret = create_netxbig_led(pdev, i, priv);
 		if (ret < 0)
 			goto err_free_leds;
 	}
-
-	platform_set_drvdata(pdev, leds_data);
+	platform_set_drvdata(pdev, priv);
 
 	return 0;
 
 err_free_leds:
 	for (i = i - 1; i >= 0; i--)
-		delete_netxbig_led(&leds_data[i]);
+		delete_netxbig_led(&priv->leds_data[i]);
 
 	gpio_ext_free(pdata->gpio_ext);
 	return ret;
@@ -385,14 +607,12 @@  err_free_leds:
 
 static int netxbig_led_remove(struct platform_device *pdev)
 {
-	struct netxbig_led_platform_data *pdata = dev_get_platdata(&pdev->dev);
-	struct netxbig_led_data *leds_data;
+	struct netxbig_led_priv *priv = platform_get_drvdata(pdev);
+	struct netxbig_led_platform_data *pdata = priv->pdata;
 	int i;
 
-	leds_data = platform_get_drvdata(pdev);
-
 	for (i = 0; i < pdata->num_leds; i++)
-		delete_netxbig_led(&leds_data[i]);
+		delete_netxbig_led(&priv->leds_data[i]);
 
 	gpio_ext_free(pdata->gpio_ext);
 
@@ -403,7 +623,8 @@  static struct platform_driver netxbig_led_driver = {
 	.probe		= netxbig_led_probe,
 	.remove		= netxbig_led_remove,
 	.driver		= {
-		.name	= "leds-netxbig",
+		.name		= "leds-netxbig",
+		.of_match_table	= of_match_ptr(of_netxbig_leds_match),
 	},
 };
 
diff --git a/include/dt-bindings/leds/leds-netxbig.h b/include/dt-bindings/leds/leds-netxbig.h
new file mode 100644
index 000000000000..92658b0310b2
--- /dev/null
+++ b/include/dt-bindings/leds/leds-netxbig.h
@@ -0,0 +1,18 @@ 
+/*
+ * This header provides constants for netxbig 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_NETXBIG_H
+#define _DT_BINDINGS_LEDS_NETXBIG_H
+
+#define NETXBIG_LED_OFF		0
+#define NETXBIG_LED_ON		1
+#define NETXBIG_LED_SATA	2
+#define NETXBIG_LED_TIMER1	3
+#define NETXBIG_LED_TIMER2	4
+
+#endif /* _DT_BINDINGS_LEDS_NETXBIG_H */
diff --git a/include/linux/platform_data/leds-kirkwood-netxbig.h b/include/linux/platform_data/leds-kirkwood-netxbig.h
index d2be19a51acd..3c85a735c380 100644
--- a/include/linux/platform_data/leds-kirkwood-netxbig.h
+++ b/include/linux/platform_data/leds-kirkwood-netxbig.h
@@ -40,6 +40,7 @@  struct netxbig_led {
 	int		mode_addr;
 	int		*mode_val;
 	int		bright_addr;
+	int		bright_max;
 };
 
 struct netxbig_led_platform_data {