Re: [RESEND PATCH 1/4] leds: leds-ns2: move LED modes mapping outside of the driver

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

Hi Simon,

On 06/18/2015 05:17 PM, Simon Guinot wrote:
> From: Vincent Donnefort <vdonnefort@gmail.com>
>
> On the board n090401 (Seagate NAS 4-Bay), the LED mode mapping (GPIO
> values to LED mode) is different from the one used on other boards
> supported by the leds-ns2 driver.
>
> With this patch the hardcoded mapping is removed from leds-ns2. Now,
> it must be defined either in the platform data (if an old-fashion board
> setup file is used) or in the DT node. In order to allow the later, this
> patch also introduces a modes-map property for the leds-ns2 DT binding.
>
> Signed-off-by: Vincent Donnefort <vdonnefort@gmail.com>
> ---
>   .../devicetree/bindings/leds/leds-ns2.txt          |   9 ++
>   drivers/leds/leds-ns2.c                            | 102 +++++++++++----------
>   include/dt-bindings/leds/leds-ns2.h                |   8 ++
>   include/linux/platform_data/leds-kirkwood-ns2.h    |  14 +++
>   4 files changed, 85 insertions(+), 48 deletions(-)
>   create mode 100644 include/dt-bindings/leds/leds-ns2.h
>
> diff --git a/Documentation/devicetree/bindings/leds/leds-ns2.txt b/Documentation/devicetree/bindings/leds/leds-ns2.txt
> index aef3aca34d2d..9f81258a5b6e 100644
> --- a/Documentation/devicetree/bindings/leds/leds-ns2.txt
> +++ b/Documentation/devicetree/bindings/leds/leds-ns2.txt
> @@ -8,6 +8,9 @@ Each LED is represented as a sub-node of the ns2-leds device.
>   Required sub-node properties:
>   - cmd-gpio: Command LED GPIO. See OF device-tree GPIO specification.
>   - slow-gpio: Slow LED GPIO. See OF device-tree GPIO specification.
> +- modes-map: A mapping between LED modes (off, on or SATA activity blinking) and
> +  the corresponding cmd-gpio/slow-gpio values. All the GPIO values combinations
> +  should be given in order to avoid having an unknown mode at driver probe time.
>
>   Optional sub-node properties:
>   - label: Name for this LED. If omitted, the label is taken from the node name.
> @@ -15,6 +18,8 @@ Optional sub-node properties:
>
>   Example:
>
> +#include <dt-bindings/leds/leds-ns2.h>
> +
>   ns2-leds {
>   	compatible = "lacie,ns2-leds";
>
> @@ -22,5 +27,9 @@ ns2-leds {
>   		label = "ns2:blue:sata";
>   		slow-gpio = <&gpio0 29 0>;
>   		cmd-gpio = <&gpio0 30 0>;
> +		modes-map = <NS_V2_LED_OFF  0 1
> +			     NS_V2_LED_ON   1 0
> +			     NS_V2_LED_ON   0 0
> +			     NS_V2_LED_SATA 1 1>;
>   	};
>   };

This looks good to me but please cc devicetree@vger.kernel.org when you
modify DT bindings.

> diff --git a/drivers/leds/leds-ns2.c b/drivers/leds/leds-ns2.c
> index 1fd6adbb43b7..b0bc03539dbb 100644
> --- a/drivers/leds/leds-ns2.c
> +++ b/drivers/leds/leds-ns2.c
> @@ -33,46 +33,20 @@
>   #include <linux/of_gpio.h>
>
>   /*
> - * The Network Space v2 dual-GPIO LED is wired to a CPLD and can blink in
> - * relation with the SATA activity. This capability is exposed through the
> - * "sata" sysfs attribute.
> - *
> - * The following array detail the different LED registers and the combination
> - * of their possible values:
> - *
> - *  cmd_led   |  slow_led  | /SATA active | LED state
> - *            |            |              |
> - *     1      |     0      |      x       |  off
> - *     -      |     1      |      x       |  on
> - *     0      |     0      |      1       |  on
> - *     0      |     0      |      0       |  blink (rate 300ms)
> + * The Network Space v2 dual-GPIO LED is wired to a CPLD. Three different LED
> + * modes are available: off, on and SATA activity blinking. The LED modes are
> + * controlled through two GPIOs (command and slow): each combination of values
> + * for the command/slow GPIOs corresponds to a LED mode.
>    */
>
> -enum ns2_led_modes {
> -	NS_V2_LED_OFF,
> -	NS_V2_LED_ON,
> -	NS_V2_LED_SATA,
> -};
> -
> -struct ns2_led_mode_value {
> -	enum ns2_led_modes	mode;
> -	int			cmd_level;
> -	int			slow_level;
> -};
> -
> -static struct ns2_led_mode_value ns2_led_modval[] = {
> -	{ NS_V2_LED_OFF	, 1, 0 },
> -	{ NS_V2_LED_ON	, 0, 1 },
> -	{ NS_V2_LED_ON	, 1, 1 },
> -	{ NS_V2_LED_SATA, 0, 0 },
> -};
> -
>   struct ns2_led_data {
>   	struct led_classdev	cdev;
>   	unsigned		cmd;
>   	unsigned		slow;
>   	unsigned char		sata; /* True when SATA mode active. */
>   	rwlock_t		rw_lock; /* Lock GPIOs. */
> +	int			num_modes;
> +	struct ns2_led_modval	*modval;
>   };
>
>   static int ns2_led_get_mode(struct ns2_led_data *led_dat,
> @@ -88,10 +62,10 @@ static int ns2_led_get_mode(struct ns2_led_data *led_dat,
>   	cmd_level = gpio_get_value(led_dat->cmd);
>   	slow_level = gpio_get_value(led_dat->slow);
>
> -	for (i = 0; i < ARRAY_SIZE(ns2_led_modval); i++) {
> -		if (cmd_level == ns2_led_modval[i].cmd_level &&
> -		    slow_level == ns2_led_modval[i].slow_level) {
> -			*mode = ns2_led_modval[i].mode;
> +	for (i = 0; i < led_dat->num_modes; i++) {
> +		if (cmd_level == led_dat->modval[i].cmd_level &&
> +		    slow_level == led_dat->modval[i].slow_level) {
> +			*mode = led_dat->modval[i].mode;
>   			ret = 0;
>   			break;
>   		}
> @@ -110,12 +84,12 @@ static void ns2_led_set_mode(struct ns2_led_data *led_dat,
>
>   	write_lock_irqsave(&led_dat->rw_lock, flags);
>
> -	for (i = 0; i < ARRAY_SIZE(ns2_led_modval); i++) {
> -		if (mode == ns2_led_modval[i].mode) {
> +	for (i = 0; i < led_dat->num_modes; i++) {
> +		if (mode == led_dat->modval[i].mode) {
>   			gpio_set_value(led_dat->cmd,
> -				       ns2_led_modval[i].cmd_level);
> +				       led_dat->modval[i].cmd_level);
>   			gpio_set_value(led_dat->slow,
> -				       ns2_led_modval[i].slow_level);
> +				       led_dat->modval[i].slow_level);
>   		}
>   	}
>
> @@ -228,6 +202,8 @@ create_ns2_led(struct platform_device *pdev, struct ns2_led_data *led_dat,
>   	led_dat->cdev.groups = ns2_led_groups;
>   	led_dat->cmd = template->cmd;
>   	led_dat->slow = template->slow;
> +	led_dat->modval = template->modval;
> +	led_dat->num_modes = template->num_modes;
>
>   	ret = ns2_led_get_mode(led_dat, &mode);
>   	if (ret < 0)
> @@ -259,9 +235,8 @@ ns2_leds_get_of_pdata(struct device *dev, struct ns2_led_platform_data *pdata)
>   {
>   	struct device_node *np = dev->of_node;
>   	struct device_node *child;
> -	struct ns2_led *leds;
> +	struct ns2_led *led, *leds;
>   	int num_leds = 0;
> -	int i = 0;
>
>   	num_leds = of_get_child_count(np);
>   	if (!num_leds)
> @@ -272,26 +247,57 @@ ns2_leds_get_of_pdata(struct device *dev, struct ns2_led_platform_data *pdata)
>   	if (!leds)
>   		return -ENOMEM;
>
> +	led = leds;
>   	for_each_child_of_node(np, child) {
>   		const char *string;
> -		int ret;
> +		int ret, i, num_modes;
> +		struct ns2_led_modval *modval;
>
>   		ret = of_get_named_gpio(child, "cmd-gpio", 0);
>   		if (ret < 0)
>   			return ret;
> -		leds[i].cmd = ret;
> +		led->cmd = ret;
>   		ret = of_get_named_gpio(child, "slow-gpio", 0);
>   		if (ret < 0)
>   			return ret;
> -		leds[i].slow = ret;
> +		led->slow = ret;
>   		ret = of_property_read_string(child, "label", &string);
> -		leds[i].name = (ret == 0) ? string : child->name;
> +		led->name = (ret == 0) ? string : child->name;
>   		ret = of_property_read_string(child, "linux,default-trigger",
>   					      &string);
>   		if (ret == 0)
> -			leds[i].default_trigger = string;
> +			led->default_trigger = string;
> +
> +		ret = of_property_count_u32_elems(child, "modes-map");

I think that we shouldn't fail if the property is absent, but default
to the mapping that is currently hard coded in the driver. Otherwise
we would break existing users.

> +		if (ret < 0 || ret % 3) {
> +			dev_err(dev,
> +				"Missing or malformed modes-map property\n");
> +			return -EINVAL;
> +		}
> +
> +		num_modes = ret / 3;
> +		modval = devm_kzalloc(dev,
> +				      num_modes * sizeof(struct ns2_led_modval),
> +				      GFP_KERNEL);
> +		if (!modval)
> +			return -ENOMEM;
> +
> +		for (i = 0; i < num_modes; i++) {
> +			of_property_read_u32_index(child,
> +						"modes-map", 3 * i,
> +						(u32 *) &modval[i].mode);
> +			of_property_read_u32_index(child,
> +						"modes-map", 3 * i + 1,
> +						(u32 *) &modval[i].cmd_level);
> +			of_property_read_u32_index(child,
> +						"modes-map", 3 * i + 2,
> +						(u32 *) &modval[i].slow_level);
> +		}
> +
> +		led->num_modes = num_modes;
> +		led->modval = modval;
>
> -		i++;
> +		led++;
>   	}
>
>   	pdata->leds = leds;
> diff --git a/include/dt-bindings/leds/leds-ns2.h b/include/dt-bindings/leds/leds-ns2.h
> new file mode 100644
> index 000000000000..491c5f974a92
> --- /dev/null
> +++ b/include/dt-bindings/leds/leds-ns2.h
> @@ -0,0 +1,8 @@
> +#ifndef _DT_BINDINGS_LEDS_NS2_H
> +#define _DT_BINDINGS_LEDS_NS2_H
> +
> +#define NS_V2_LED_OFF	0
> +#define NS_V2_LED_ON	1
> +#define NS_V2_LED_SATA	2
> +
> +#endif
> diff --git a/include/linux/platform_data/leds-kirkwood-ns2.h b/include/linux/platform_data/leds-kirkwood-ns2.h
> index 6a9fed57f346..eb8a6860e816 100644
> --- a/include/linux/platform_data/leds-kirkwood-ns2.h
> +++ b/include/linux/platform_data/leds-kirkwood-ns2.h
> @@ -9,11 +9,25 @@
>   #ifndef __LEDS_KIRKWOOD_NS2_H
>   #define __LEDS_KIRKWOOD_NS2_H
>
> +enum ns2_led_modes {
> +	NS_V2_LED_OFF,
> +	NS_V2_LED_ON,
> +	NS_V2_LED_SATA,
> +};
> +
> +struct ns2_led_modval {
> +	enum ns2_led_modes	mode;
> +	int			cmd_level;
> +	int			slow_level;
> +};
> +
>   struct ns2_led {
>   	const char	*name;
>   	const char	*default_trigger;
>   	unsigned	cmd;
>   	unsigned	slow;
> +	int		num_modes;
> +	struct ns2_led_modval *modval;
>   };
>
>   struct ns2_led_platform_data {
>


-- 
Best Regards,
Jacek Anaszewski