[linux-2.6-block.git] / drivers / leds / leds-turris-omnia.c

// SPDX-License-Identifier: GPL-2.0
/*
 * CZ.NIC's Turris Omnia LEDs driver
 *
 * 2020, 2023 by Marek Behún <kabel@kernel.org>
 */

#include <linux/i2c.h>
#include <linux/led-class-multicolor.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/of.h>
#include "leds.h"

#define OMNIA_BOARD_LEDS	12
#define OMNIA_LED_NUM_CHANNELS	3

/* MCU controller commands at I2C address 0x2a */
#define OMNIA_MCU_I2C_ADDR		0x2a

#define CMD_GET_STATUS_WORD		0x01
#define STS_FEATURES_SUPPORTED		BIT(2)

#define CMD_GET_FEATURES		0x10
#define FEAT_LED_GAMMA_CORRECTION	BIT(5)

/* LED controller commands at I2C address 0x2b */
#define CMD_LED_MODE			0x03
#define CMD_LED_MODE_LED(l)		((l) & 0x0f)
#define CMD_LED_MODE_USER		0x10

#define CMD_LED_STATE			0x04
#define CMD_LED_STATE_LED(l)		((l) & 0x0f)
#define CMD_LED_STATE_ON		0x10

#define CMD_LED_COLOR			0x05
#define CMD_LED_SET_BRIGHTNESS		0x07
#define CMD_LED_GET_BRIGHTNESS		0x08

#define CMD_SET_GAMMA_CORRECTION	0x30
#define CMD_GET_GAMMA_CORRECTION	0x31

struct omnia_led {
	struct led_classdev_mc mc_cdev;
	struct mc_subled subled_info[OMNIA_LED_NUM_CHANNELS];
	u8 cached_channels[OMNIA_LED_NUM_CHANNELS];
	bool on, hwtrig;
	int reg;
};

#define to_omnia_led(l)		container_of(l, struct omnia_led, mc_cdev)

struct omnia_leds {
	struct i2c_client *client;
	struct mutex lock;
	bool has_gamma_correction;
	struct omnia_led leds[];
};

static int omnia_cmd_write_u8(const struct i2c_client *client, u8 cmd, u8 val)
{
	u8 buf[2] = { cmd, val };
	int ret;

	ret = i2c_master_send(client, buf, sizeof(buf));

	return ret < 0 ? ret : 0;
}

static int omnia_cmd_read_raw(struct i2c_adapter *adapter, u8 addr, u8 cmd,
			      void *reply, size_t len)
{
	struct i2c_msg msgs[2];
	int ret;

	msgs[0].addr = addr;
	msgs[0].flags = 0;
	msgs[0].len = 1;
	msgs[0].buf = &cmd;
	msgs[1].addr = addr;
	msgs[1].flags = I2C_M_RD;
	msgs[1].len = len;
	msgs[1].buf = reply;

	ret = i2c_transfer(adapter, msgs, ARRAY_SIZE(msgs));
	if (likely(ret == ARRAY_SIZE(msgs)))
		return 0;
	else if (ret < 0)
		return ret;
	else
		return -EIO;
}

static int omnia_cmd_read_u8(const struct i2c_client *client, u8 cmd)
{
	u8 reply;
	int err;

	err = omnia_cmd_read_raw(client->adapter, client->addr, cmd, &reply, 1);
	if (err)
		return err;

	return reply;
}

static int omnia_led_send_color_cmd(const struct i2c_client *client,
				    struct omnia_led *led)
{
	char cmd[5];
	int ret;

	cmd[0] = CMD_LED_COLOR;
	cmd[1] = led->reg;
	cmd[2] = led->subled_info[0].brightness;
	cmd[3] = led->subled_info[1].brightness;
	cmd[4] = led->subled_info[2].brightness;

	/* Send the color change command */
	ret = i2c_master_send(client, cmd, 5);
	if (ret < 0)
		return ret;

	/* Cache the RGB channel brightnesses */
	for (int i = 0; i < OMNIA_LED_NUM_CHANNELS; ++i)
		led->cached_channels[i] = led->subled_info[i].brightness;

	return 0;
}

/* Determine if the computed RGB channels are different from the cached ones */
static bool omnia_led_channels_changed(struct omnia_led *led)
{
	for (int i = 0; i < OMNIA_LED_NUM_CHANNELS; ++i)
		if (led->subled_info[i].brightness != led->cached_channels[i])
			return true;

	return false;
}

static int omnia_led_brightness_set_blocking(struct led_classdev *cdev,
					     enum led_brightness brightness)
{
	struct led_classdev_mc *mc_cdev = lcdev_to_mccdev(cdev);
	struct omnia_leds *leds = dev_get_drvdata(cdev->dev->parent);
	struct omnia_led *led = to_omnia_led(mc_cdev);
	int err = 0;

	mutex_lock(&leds->lock);

	/*
	 * Only recalculate RGB brightnesses from intensities if brightness is
	 * non-zero (if it is zero and the LED is in HW blinking mode, we use
	 * max_brightness as brightness). Otherwise we won't be using them and
	 * we can save ourselves some software divisions (Omnia's CPU does not
	 * implement the division instruction).
	 */
	if (brightness || led->hwtrig) {
		led_mc_calc_color_components(mc_cdev, brightness ?:
						      cdev->max_brightness);

		/*
		 * Send color command only if brightness is non-zero and the RGB
		 * channel brightnesses changed.
		 */
		if (omnia_led_channels_changed(led))
			err = omnia_led_send_color_cmd(leds->client, led);
	}

	/*
	 * Send on/off state change only if (bool)brightness changed and the LED
	 * is not being blinked by HW.
	 */
	if (!err && !led->hwtrig && !brightness != !led->on) {
		u8 state = CMD_LED_STATE_LED(led->reg);

		if (brightness)
			state |= CMD_LED_STATE_ON;

		err = omnia_cmd_write_u8(leds->client, CMD_LED_STATE, state);
		if (!err)
			led->on = !!brightness;
	}

	mutex_unlock(&leds->lock);

	return err;
}

static struct led_hw_trigger_type omnia_hw_trigger_type;

static int omnia_hwtrig_activate(struct led_classdev *cdev)
{
	struct led_classdev_mc *mc_cdev = lcdev_to_mccdev(cdev);
	struct omnia_leds *leds = dev_get_drvdata(cdev->dev->parent);
	struct omnia_led *led = to_omnia_led(mc_cdev);
	int err = 0;

	mutex_lock(&leds->lock);

	if (!led->on) {
		/*
		 * If the LED is off (brightness was set to 0), the last
		 * configured color was not necessarily sent to the MCU.
		 * Recompute with max_brightness and send if needed.
		 */
		led_mc_calc_color_components(mc_cdev, cdev->max_brightness);

		if (omnia_led_channels_changed(led))
			err = omnia_led_send_color_cmd(leds->client, led);
	}

	if (!err) {
		/* Put the LED into MCU controlled mode */
		err = omnia_cmd_write_u8(leds->client, CMD_LED_MODE,
					 CMD_LED_MODE_LED(led->reg));
		if (!err)
			led->hwtrig = true;
	}

	mutex_unlock(&leds->lock);

	return err;
}

static void omnia_hwtrig_deactivate(struct led_classdev *cdev)
{
	struct omnia_leds *leds = dev_get_drvdata(cdev->dev->parent);
	struct omnia_led *led = to_omnia_led(lcdev_to_mccdev(cdev));
	int err;

	mutex_lock(&leds->lock);

	led->hwtrig = false;

	/* Put the LED into software mode */
	err = omnia_cmd_write_u8(leds->client, CMD_LED_MODE,
				 CMD_LED_MODE_LED(led->reg) |
				 CMD_LED_MODE_USER);

	mutex_unlock(&leds->lock);

	if (err)
		dev_err(cdev->dev, "Cannot put LED to software mode: %i\n",
			err);
}

static struct led_trigger omnia_hw_trigger = {
	.name		= "omnia-mcu",
	.activate	= omnia_hwtrig_activate,
	.deactivate	= omnia_hwtrig_deactivate,
	.trigger_type	= &omnia_hw_trigger_type,
};

static int omnia_led_register(struct i2c_client *client, struct omnia_led *led,
			      struct device_node *np)
{
	struct led_init_data init_data = {};
	struct device *dev = &client->dev;
	struct led_classdev *cdev;
	int ret, color;

	ret = of_property_read_u32(np, "reg", &led->reg);
	if (ret || led->reg >= OMNIA_BOARD_LEDS) {
		dev_warn(dev,
			 "Node %pOF: must contain 'reg' property with values between 0 and %i\n",
			 np, OMNIA_BOARD_LEDS - 1);
		return 0;
	}

	ret = of_property_read_u32(np, "color", &color);
	if (ret || color != LED_COLOR_ID_RGB) {
		dev_warn(dev,
			 "Node %pOF: must contain 'color' property with value LED_COLOR_ID_RGB\n",
			 np);
		return 0;
	}

	led->subled_info[0].color_index = LED_COLOR_ID_RED;
	led->subled_info[1].color_index = LED_COLOR_ID_GREEN;
	led->subled_info[2].color_index = LED_COLOR_ID_BLUE;

	/* Initial color is white */
	for (int i = 0; i < OMNIA_LED_NUM_CHANNELS; ++i) {
		led->subled_info[i].intensity = 255;
		led->subled_info[i].brightness = 255;
		led->subled_info[i].channel = i;
	}

	led->mc_cdev.subled_info = led->subled_info;
	led->mc_cdev.num_colors = OMNIA_LED_NUM_CHANNELS;

	init_data.fwnode = &np->fwnode;

	cdev = &led->mc_cdev.led_cdev;
	cdev->max_brightness = 255;
	cdev->brightness_set_blocking = omnia_led_brightness_set_blocking;
	cdev->trigger_type = &omnia_hw_trigger_type;
	/*
	 * Use the omnia-mcu trigger as the default trigger. It may be rewritten
	 * by LED class from the linux,default-trigger property.
	 */
	cdev->default_trigger = omnia_hw_trigger.name;

	/* put the LED into software mode */
	ret = omnia_cmd_write_u8(client, CMD_LED_MODE,
				 CMD_LED_MODE_LED(led->reg) |
				 CMD_LED_MODE_USER);
	if (ret) {
		dev_err(dev, "Cannot set LED %pOF to software mode: %i\n", np,
			ret);
		return ret;
	}

	/* disable the LED */
	ret = omnia_cmd_write_u8(client, CMD_LED_STATE,
				 CMD_LED_STATE_LED(led->reg));
	if (ret) {
		dev_err(dev, "Cannot set LED %pOF brightness: %i\n", np, ret);
		return ret;
	}

	/* Set initial color and cache it */
	ret = omnia_led_send_color_cmd(client, led);
	if (ret < 0) {
		dev_err(dev, "Cannot set LED %pOF initial color: %i\n", np,
			ret);
		return ret;
	}

	ret = devm_led_classdev_multicolor_register_ext(dev, &led->mc_cdev,
							&init_data);
	if (ret < 0) {
		dev_err(dev, "Cannot register LED %pOF: %i\n", np, ret);
		return ret;
	}

	return 1;
}

/*
 * On the front panel of the Turris Omnia router there is also a button which
 * can be used to control the intensity of all the LEDs at once, so that if they
 * are too bright, user can dim them.
 * The microcontroller cycles between 8 levels of this global brightness (from
 * 100% to 0%), but this setting can have any integer value between 0 and 100.
 * It is therefore convenient to be able to change this setting from software.
 * We expose this setting via a sysfs attribute file called "brightness". This
 * file lives in the device directory of the LED controller, not an individual
 * LED, so it should not confuse users.
 */
static ssize_t brightness_show(struct device *dev, struct device_attribute *a,
			       char *buf)
{
	struct i2c_client *client = to_i2c_client(dev);
	int ret;

	ret = omnia_cmd_read_u8(client, CMD_LED_GET_BRIGHTNESS);

	if (ret < 0)
		return ret;

	return sysfs_emit(buf, "%d\n", ret);
}

static ssize_t brightness_store(struct device *dev, struct device_attribute *a,
				const char *buf, size_t count)
{
	struct i2c_client *client = to_i2c_client(dev);
	unsigned long brightness;
	int err;

	if (kstrtoul(buf, 10, &brightness))
		return -EINVAL;

	if (brightness > 100)
		return -EINVAL;

	err = omnia_cmd_write_u8(client, CMD_LED_SET_BRIGHTNESS, brightness);

	return err ?: count;
}
static DEVICE_ATTR_RW(brightness);

static ssize_t gamma_correction_show(struct device *dev,
				     struct device_attribute *a, char *buf)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct omnia_leds *leds = i2c_get_clientdata(client);
	int ret;

	if (leds->has_gamma_correction) {
		ret = omnia_cmd_read_u8(client, CMD_GET_GAMMA_CORRECTION);
		if (ret < 0)
			return ret;
	} else {
		ret = 0;
	}

	return sysfs_emit(buf, "%d\n", !!ret);
}

static ssize_t gamma_correction_store(struct device *dev,
				      struct device_attribute *a,
				      const char *buf, size_t count)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct omnia_leds *leds = i2c_get_clientdata(client);
	bool val;
	int err;

	if (!leds->has_gamma_correction)
		return -EOPNOTSUPP;

	if (kstrtobool(buf, &val) < 0)
		return -EINVAL;

	err = omnia_cmd_write_u8(client, CMD_SET_GAMMA_CORRECTION, val);

	return err ?: count;
}
static DEVICE_ATTR_RW(gamma_correction);

static struct attribute *omnia_led_controller_attrs[] = {
	&dev_attr_brightness.attr,
	&dev_attr_gamma_correction.attr,
	NULL,
};
ATTRIBUTE_GROUPS(omnia_led_controller);

static int omnia_mcu_get_features(const struct i2c_client *client)
{
	u16 reply;
	int err;

	err = omnia_cmd_read_raw(client->adapter, OMNIA_MCU_I2C_ADDR,
				 CMD_GET_STATUS_WORD, &reply, sizeof(reply));
	if (err)
		return err;

	/* Check whether MCU firmware supports the CMD_GET_FEAUTRES command */
	if (!(le16_to_cpu(reply) & STS_FEATURES_SUPPORTED))
		return 0;

	err = omnia_cmd_read_raw(client->adapter, OMNIA_MCU_I2C_ADDR,
				 CMD_GET_FEATURES, &reply, sizeof(reply));
	if (err)
		return err;

	return le16_to_cpu(reply);
}

static int omnia_leds_probe(struct i2c_client *client)
{
	struct device *dev = &client->dev;
	struct device_node *np = dev_of_node(dev);
	struct omnia_leds *leds;
	struct omnia_led *led;
	int ret, count;

	count = of_get_available_child_count(np);
	if (!count) {
		dev_err(dev, "LEDs are not defined in device tree!\n");
		return -ENODEV;
	} else if (count > OMNIA_BOARD_LEDS) {
		dev_err(dev, "Too many LEDs defined in device tree!\n");
		return -EINVAL;
	}

	leds = devm_kzalloc(dev, struct_size(leds, leds, count), GFP_KERNEL);
	if (!leds)
		return -ENOMEM;

	leds->client = client;
	i2c_set_clientdata(client, leds);

	ret = omnia_mcu_get_features(client);
	if (ret < 0) {
		dev_err(dev, "Cannot determine MCU supported features: %d\n",
			ret);
		return ret;
	}

	leds->has_gamma_correction = ret & FEAT_LED_GAMMA_CORRECTION;
	if (!leds->has_gamma_correction) {
		dev_info(dev,
			 "Your board's MCU firmware does not support the LED gamma correction feature.\n");
		dev_info(dev,
			 "Consider upgrading MCU firmware with the omnia-mcutool utility.\n");
	}

	mutex_init(&leds->lock);

	ret = devm_led_trigger_register(dev, &omnia_hw_trigger);
	if (ret < 0) {
		dev_err(dev, "Cannot register private LED trigger: %d\n", ret);
		return ret;
	}

	led = &leds->leds[0];
	for_each_available_child_of_node_scoped(np, child) {
		ret = omnia_led_register(client, led, child);
		if (ret < 0)
			return ret;

		led += ret;
	}

	return 0;
}

static void omnia_leds_remove(struct i2c_client *client)
{
	u8 buf[5];

	/* put all LEDs into default (HW triggered) mode */
	omnia_cmd_write_u8(client, CMD_LED_MODE,
			   CMD_LED_MODE_LED(OMNIA_BOARD_LEDS));

	/* set all LEDs color to [255, 255, 255] */
	buf[0] = CMD_LED_COLOR;
	buf[1] = OMNIA_BOARD_LEDS;
	buf[2] = 255;
	buf[3] = 255;
	buf[4] = 255;

	i2c_master_send(client, buf, 5);
}

static const struct of_device_id of_omnia_leds_match[] = {
	{ .compatible = "cznic,turris-omnia-leds", },
	{},
};
MODULE_DEVICE_TABLE(of, of_omnia_leds_match);

static const struct i2c_device_id omnia_id[] = {
	{ "omnia" },
	{ }
};
MODULE_DEVICE_TABLE(i2c, omnia_id);

static struct i2c_driver omnia_leds_driver = {
	.probe		= omnia_leds_probe,
	.remove		= omnia_leds_remove,
	.id_table	= omnia_id,
	.driver		= {
		.name	= "leds-turris-omnia",
		.of_match_table = of_omnia_leds_match,
		.dev_groups = omnia_led_controller_groups,
	},
};

module_i2c_driver(omnia_leds_driver);

MODULE_AUTHOR("Marek Behun <kabel@kernel.org>");
MODULE_DESCRIPTION("CZ.NIC's Turris Omnia LEDs");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
089381b2 MB	1	// SPDX-License-Identifier: GPL-2.0
	2	/*
	3	* CZ.NIC's Turris Omnia LEDs driver
	4	*
6de283b9	5	* 2020, 2023 by Marek Behún <kabel@kernel.org>
089381b2 MB	6	*/
	7
	8	#include <linux/i2c.h>
	9	#include <linux/led-class-multicolor.h>
	10	#include <linux/module.h>
	11	#include <linux/mutex.h>
	12	#include <linux/of.h>
	13	#include "leds.h"
	14
5d47ce1d MB	15	#define OMNIA_BOARD_LEDS 12
5d47ce1d MB	16	#define OMNIA_LED_NUM_CHANNELS 3
089381b2	17
43e9082f MB	18	/* MCU controller commands at I2C address 0x2a */
43e9082f MB	19	#define OMNIA_MCU_I2C_ADDR 0x2a
089381b2	20
43e9082f MB	21	#define CMD_GET_STATUS_WORD 0x01
43e9082f MB	22	#define STS_FEATURES_SUPPORTED BIT(2)
089381b2	23
43e9082f MB	24	#define CMD_GET_FEATURES 0x10
	25	#define FEAT_LED_GAMMA_CORRECTION BIT(5)
	26
	27	/* LED controller commands at I2C address 0x2b */
	28	#define CMD_LED_MODE 0x03
	29	#define CMD_LED_MODE_LED(l) ((l) & 0x0f)
	30	#define CMD_LED_MODE_USER 0x10
	31
	32	#define CMD_LED_STATE 0x04
	33	#define CMD_LED_STATE_LED(l) ((l) & 0x0f)
	34	#define CMD_LED_STATE_ON 0x10
	35
	36	#define CMD_LED_COLOR 0x05
	37	#define CMD_LED_SET_BRIGHTNESS 0x07
	38	#define CMD_LED_GET_BRIGHTNESS 0x08
	39
	40	#define CMD_SET_GAMMA_CORRECTION 0x30
	41	#define CMD_GET_GAMMA_CORRECTION 0x31
089381b2	42
089381b2 MB	43	struct omnia_led {
	44	struct led_classdev_mc mc_cdev;
	45	struct mc_subled subled_info[OMNIA_LED_NUM_CHANNELS];
9f028c9e	46	u8 cached_channels[OMNIA_LED_NUM_CHANNELS];
cbd6954f	47	bool on, hwtrig;
089381b2 MB	48	int reg;
	49	};
	50
5d47ce1d	51	#define to_omnia_led(l) container_of(l, struct omnia_led, mc_cdev)
089381b2 MB	52
	53	struct omnia_leds {
	54	struct i2c_client *client;
	55	struct mutex lock;
43e9082f	56	bool has_gamma_correction;
089381b2 MB	57	struct omnia_led leds[];
	58	};
	59
6de283b9 MB	60	static int omnia_cmd_write_u8(const struct i2c_client *client, u8 cmd, u8 val)
	61	{
	62	u8 buf[2] = { cmd, val };
78cbcfd8 MB	63	int ret;
	64
	65	ret = i2c_master_send(client, buf, sizeof(buf));
6de283b9	66
78cbcfd8	67	return ret < 0 ? ret : 0;
6de283b9 MB	68	}
6de283b9 MB	69
43e9082f MB	70	static int omnia_cmd_read_raw(struct i2c_adapter *adapter, u8 addr, u8 cmd,
43e9082f MB	71	void *reply, size_t len)
6de283b9 MB	72	{
6de283b9 MB	73	struct i2c_msg msgs[2];
6de283b9 MB	74	int ret;
6de283b9 MB	75
43e9082f	76	msgs[0].addr = addr;
6de283b9 MB	77	msgs[0].flags = 0;
	78	msgs[0].len = 1;
	79	msgs[0].buf = &cmd;
43e9082f	80	msgs[1].addr = addr;
6de283b9	81	msgs[1].flags = I2C_M_RD;
43e9082f MB	82	msgs[1].len = len;
43e9082f MB	83	msgs[1].buf = reply;
6de283b9	84
43e9082f	85	ret = i2c_transfer(adapter, msgs, ARRAY_SIZE(msgs));
6de283b9	86	if (likely(ret == ARRAY_SIZE(msgs)))
78cbcfd8	87	return 0;
6de283b9 MB	88	else if (ret < 0)
	89	return ret;
	90	else
	91	return -EIO;
	92	}
	93
43e9082f MB	94	static int omnia_cmd_read_u8(const struct i2c_client *client, u8 cmd)
	95	{
	96	u8 reply;
78cbcfd8	97	int err;
43e9082f	98
78cbcfd8 MB	99	err = omnia_cmd_read_raw(client->adapter, client->addr, cmd, &reply, 1);
	100	if (err)
	101	return err;
43e9082f MB	102
	103	return reply;
	104	}
	105
9f028c9e MB	106	static int omnia_led_send_color_cmd(const struct i2c_client *client,
	107	struct omnia_led *led)
	108	{
	109	char cmd[5];
	110	int ret;
	111
	112	cmd[0] = CMD_LED_COLOR;
	113	cmd[1] = led->reg;
	114	cmd[2] = led->subled_info[0].brightness;
	115	cmd[3] = led->subled_info[1].brightness;
	116	cmd[4] = led->subled_info[2].brightness;
	117
	118	/* Send the color change command */
	119	ret = i2c_master_send(client, cmd, 5);
	120	if (ret < 0)
	121	return ret;
	122
	123	/* Cache the RGB channel brightnesses */
	124	for (int i = 0; i < OMNIA_LED_NUM_CHANNELS; ++i)
	125	led->cached_channels[i] = led->subled_info[i].brightness;
	126
	127	return 0;
	128	}
	129
	130	/* Determine if the computed RGB channels are different from the cached ones */
	131	static bool omnia_led_channels_changed(struct omnia_led *led)
	132	{
	133	for (int i = 0; i < OMNIA_LED_NUM_CHANNELS; ++i)
	134	if (led->subled_info[i].brightness != led->cached_channels[i])
	135	return true;
	136
	137	return false;
	138	}
	139
089381b2 MB	140	static int omnia_led_brightness_set_blocking(struct led_classdev *cdev,
	141	enum led_brightness brightness)
	142	{
	143	struct led_classdev_mc *mc_cdev = lcdev_to_mccdev(cdev);
	144	struct omnia_leds *leds = dev_get_drvdata(cdev->dev->parent);
	145	struct omnia_led *led = to_omnia_led(mc_cdev);
9f028c9e	146	int err = 0;
089381b2 MB	147
	148	mutex_lock(&leds->lock);
	149
9f028c9e MB	150	/*
9f028c9e MB	151	* Only recalculate RGB brightnesses from intensities if brightness is
cbd6954f MB	152	* non-zero (if it is zero and the LED is in HW blinking mode, we use
	153	* max_brightness as brightness). Otherwise we won't be using them and
	154	* we can save ourselves some software divisions (Omnia's CPU does not
	155	* implement the division instruction).
9f028c9e	156	*/
cbd6954f MB	157	if (brightness \|\| led->hwtrig) {
	158	led_mc_calc_color_components(mc_cdev, brightness ?:
	159	cdev->max_brightness);
9f028c9e MB	160
	161	/*
	162	* Send color command only if brightness is non-zero and the RGB
	163	* channel brightnesses changed.
	164	*/
	165	if (omnia_led_channels_changed(led))
	166	err = omnia_led_send_color_cmd(leds->client, led);
	167	}
089381b2	168
cbd6954f MB	169	/*
	170	* Send on/off state change only if (bool)brightness changed and the LED
	171	* is not being blinked by HW.
	172	*/
	173	if (!err && !led->hwtrig && !brightness != !led->on) {
9f028c9e	174	u8 state = CMD_LED_STATE_LED(led->reg);
089381b2	175
9f028c9e MB	176	if (brightness)
9f028c9e MB	177	state \|= CMD_LED_STATE_ON;
089381b2	178
9f028c9e MB	179	err = omnia_cmd_write_u8(leds->client, CMD_LED_STATE, state);
	180	if (!err)
	181	led->on = !!brightness;
	182	}
089381b2 MB	183
	184	mutex_unlock(&leds->lock);
	185
9f028c9e	186	return err;
089381b2 MB	187	}
089381b2 MB	188
cbd6954f MB	189	static struct led_hw_trigger_type omnia_hw_trigger_type;
	190
	191	static int omnia_hwtrig_activate(struct led_classdev *cdev)
	192	{
	193	struct led_classdev_mc *mc_cdev = lcdev_to_mccdev(cdev);
	194	struct omnia_leds *leds = dev_get_drvdata(cdev->dev->parent);
	195	struct omnia_led *led = to_omnia_led(mc_cdev);
	196	int err = 0;
	197
	198	mutex_lock(&leds->lock);
	199
	200	if (!led->on) {
	201	/*
	202	* If the LED is off (brightness was set to 0), the last
	203	* configured color was not necessarily sent to the MCU.
	204	* Recompute with max_brightness and send if needed.
	205	*/
	206	led_mc_calc_color_components(mc_cdev, cdev->max_brightness);
	207
	208	if (omnia_led_channels_changed(led))
	209	err = omnia_led_send_color_cmd(leds->client, led);
	210	}
	211
	212	if (!err) {
	213	/* Put the LED into MCU controlled mode */
	214	err = omnia_cmd_write_u8(leds->client, CMD_LED_MODE,
	215	CMD_LED_MODE_LED(led->reg));
	216	if (!err)
	217	led->hwtrig = true;
	218	}
	219
	220	mutex_unlock(&leds->lock);
	221
	222	return err;
	223	}
	224
	225	static void omnia_hwtrig_deactivate(struct led_classdev *cdev)
	226	{
	227	struct omnia_leds *leds = dev_get_drvdata(cdev->dev->parent);
	228	struct omnia_led *led = to_omnia_led(lcdev_to_mccdev(cdev));
	229	int err;
	230
	231	mutex_lock(&leds->lock);
	232
	233	led->hwtrig = false;
	234
	235	/* Put the LED into software mode */
	236	err = omnia_cmd_write_u8(leds->client, CMD_LED_MODE,
	237	CMD_LED_MODE_LED(led->reg) \|
	238	CMD_LED_MODE_USER);
	239
	240	mutex_unlock(&leds->lock);
	241
78cbcfd8	242	if (err)
cbd6954f MB	243	dev_err(cdev->dev, "Cannot put LED to software mode: %i\n",
	244	err);
	245	}
	246
	247	static struct led_trigger omnia_hw_trigger = {
	248	.name = "omnia-mcu",
	249	.activate = omnia_hwtrig_activate,
	250	.deactivate = omnia_hwtrig_deactivate,
	251	.trigger_type = &omnia_hw_trigger_type,
	252	};
	253
089381b2 MB	254	static int omnia_led_register(struct i2c_client client, struct omnia_led led,
	255	struct device_node *np)
	256	{
	257	struct led_init_data init_data = {};
	258	struct device *dev = &client->dev;
	259	struct led_classdev *cdev;
	260	int ret, color;
	261
	262	ret = of_property_read_u32(np, "reg", &led->reg);
	263	if (ret \|\| led->reg >= OMNIA_BOARD_LEDS) {
	264	dev_warn(dev,
	265	"Node %pOF: must contain 'reg' property with values between 0 and %i\n",
	266	np, OMNIA_BOARD_LEDS - 1);
	267	return 0;
	268	}
	269
	270	ret = of_property_read_u32(np, "color", &color);
98650b08	271	if (ret \|\| color != LED_COLOR_ID_RGB) {
089381b2	272	dev_warn(dev,
98650b08	273	"Node %pOF: must contain 'color' property with value LED_COLOR_ID_RGB\n",
089381b2 MB	274	np);
	275	return 0;
	276	}
	277
	278	led->subled_info[0].color_index = LED_COLOR_ID_RED;
089381b2	279	led->subled_info[1].color_index = LED_COLOR_ID_GREEN;
089381b2	280	led->subled_info[2].color_index = LED_COLOR_ID_BLUE;
9f028c9e MB	281
	282	/* Initial color is white */
	283	for (int i = 0; i < OMNIA_LED_NUM_CHANNELS; ++i) {
	284	led->subled_info[i].intensity = 255;
	285	led->subled_info[i].brightness = 255;
	286	led->subled_info[i].channel = i;
	287	}
089381b2 MB	288
	289	led->mc_cdev.subled_info = led->subled_info;
	290	led->mc_cdev.num_colors = OMNIA_LED_NUM_CHANNELS;
	291
	292	init_data.fwnode = &np->fwnode;
	293
	294	cdev = &led->mc_cdev.led_cdev;
	295	cdev->max_brightness = 255;
	296	cdev->brightness_set_blocking = omnia_led_brightness_set_blocking;
cbd6954f MB	297	cdev->trigger_type = &omnia_hw_trigger_type;
	298	/*
	299	* Use the omnia-mcu trigger as the default trigger. It may be rewritten
	300	* by LED class from the linux,default-trigger property.
	301	*/
	302	cdev->default_trigger = omnia_hw_trigger.name;
089381b2	303
089381b2	304	/* put the LED into software mode */
6de283b9 MB	305	ret = omnia_cmd_write_u8(client, CMD_LED_MODE,
	306	CMD_LED_MODE_LED(led->reg) \|
	307	CMD_LED_MODE_USER);
78cbcfd8	308	if (ret) {
5d47ce1d MB	309	dev_err(dev, "Cannot set LED %pOF to software mode: %i\n", np,
5d47ce1d MB	310	ret);
089381b2 MB	311	return ret;
	312	}
	313
	314	/* disable the LED */
6de283b9 MB	315	ret = omnia_cmd_write_u8(client, CMD_LED_STATE,
6de283b9 MB	316	CMD_LED_STATE_LED(led->reg));
78cbcfd8	317	if (ret) {
089381b2 MB	318	dev_err(dev, "Cannot set LED %pOF brightness: %i\n", np, ret);
	319	return ret;
	320	}
	321
9f028c9e MB	322	/* Set initial color and cache it */
	323	ret = omnia_led_send_color_cmd(client, led);
	324	if (ret < 0) {
	325	dev_err(dev, "Cannot set LED %pOF initial color: %i\n", np,
	326	ret);
	327	return ret;
	328	}
	329
5d47ce1d MB	330	ret = devm_led_classdev_multicolor_register_ext(dev, &led->mc_cdev,
5d47ce1d MB	331	&init_data);
089381b2 MB	332	if (ret < 0) {
	333	dev_err(dev, "Cannot register LED %pOF: %i\n", np, ret);
	334	return ret;
	335	}
	336
	337	return 1;
	338	}
	339
	340	/*
	341	* On the front panel of the Turris Omnia router there is also a button which
	342	* can be used to control the intensity of all the LEDs at once, so that if they
	343	* are too bright, user can dim them.
	344	* The microcontroller cycles between 8 levels of this global brightness (from
	345	* 100% to 0%), but this setting can have any integer value between 0 and 100.
	346	* It is therefore convenient to be able to change this setting from software.
	347	* We expose this setting via a sysfs attribute file called "brightness". This
	348	* file lives in the device directory of the LED controller, not an individual
	349	* LED, so it should not confuse users.
	350	*/
5d47ce1d MB	351	static ssize_t brightness_show(struct device dev, struct device_attribute a,
5d47ce1d MB	352	char *buf)
089381b2 MB	353	{
089381b2 MB	354	struct i2c_client *client = to_i2c_client(dev);
089381b2 MB	355	int ret;
089381b2 MB	356
6de283b9	357	ret = omnia_cmd_read_u8(client, CMD_LED_GET_BRIGHTNESS);
089381b2 MB	358
	359	if (ret < 0)
	360	return ret;
	361
72a29725	362	return sysfs_emit(buf, "%d\n", ret);
089381b2 MB	363	}
089381b2 MB	364
5d47ce1d MB	365	static ssize_t brightness_store(struct device dev, struct device_attribute a,
5d47ce1d MB	366	const char *buf, size_t count)
089381b2 MB	367	{
089381b2 MB	368	struct i2c_client *client = to_i2c_client(dev);
fca050bb	369	unsigned long brightness;
78cbcfd8	370	int err;
089381b2	371
fca050bb	372	if (kstrtoul(buf, 10, &brightness))
089381b2 MB	373	return -EINVAL;
	374
	375	if (brightness > 100)
	376	return -EINVAL;
	377
78cbcfd8	378	err = omnia_cmd_write_u8(client, CMD_LED_SET_BRIGHTNESS, brightness);
089381b2	379
78cbcfd8	380	return err ?: count;
089381b2 MB	381	}
	382	static DEVICE_ATTR_RW(brightness);
	383
43e9082f MB	384	static ssize_t gamma_correction_show(struct device *dev,
	385	struct device_attribute a, char buf)
	386	{
	387	struct i2c_client *client = to_i2c_client(dev);
	388	struct omnia_leds *leds = i2c_get_clientdata(client);
	389	int ret;
	390
	391	if (leds->has_gamma_correction) {
	392	ret = omnia_cmd_read_u8(client, CMD_GET_GAMMA_CORRECTION);
	393	if (ret < 0)
	394	return ret;
	395	} else {
	396	ret = 0;
	397	}
	398
	399	return sysfs_emit(buf, "%d\n", !!ret);
	400	}
	401
	402	static ssize_t gamma_correction_store(struct device *dev,
	403	struct device_attribute *a,
	404	const char *buf, size_t count)
	405	{
	406	struct i2c_client *client = to_i2c_client(dev);
	407	struct omnia_leds *leds = i2c_get_clientdata(client);
	408	bool val;
78cbcfd8	409	int err;
43e9082f MB	410
	411	if (!leds->has_gamma_correction)
	412	return -EOPNOTSUPP;
	413
	414	if (kstrtobool(buf, &val) < 0)
	415	return -EINVAL;
	416
78cbcfd8	417	err = omnia_cmd_write_u8(client, CMD_SET_GAMMA_CORRECTION, val);
43e9082f	418
78cbcfd8	419	return err ?: count;
43e9082f MB	420	}
	421	static DEVICE_ATTR_RW(gamma_correction);
	422
089381b2 MB	423	static struct attribute *omnia_led_controller_attrs[] = {
089381b2 MB	424	&dev_attr_brightness.attr,
43e9082f	425	&dev_attr_gamma_correction.attr,
089381b2 MB	426	NULL,
	427	};
	428	ATTRIBUTE_GROUPS(omnia_led_controller);
	429
43e9082f MB	430	static int omnia_mcu_get_features(const struct i2c_client *client)
	431	{
	432	u16 reply;
	433	int err;
	434
	435	err = omnia_cmd_read_raw(client->adapter, OMNIA_MCU_I2C_ADDR,
	436	CMD_GET_STATUS_WORD, &reply, sizeof(reply));
78cbcfd8	437	if (err)
43e9082f MB	438	return err;
	439
	440	/* Check whether MCU firmware supports the CMD_GET_FEAUTRES command */
	441	if (!(le16_to_cpu(reply) & STS_FEATURES_SUPPORTED))
	442	return 0;
	443
	444	err = omnia_cmd_read_raw(client->adapter, OMNIA_MCU_I2C_ADDR,
	445	CMD_GET_FEATURES, &reply, sizeof(reply));
78cbcfd8	446	if (err)
43e9082f MB	447	return err;
	448
	449	return le16_to_cpu(reply);
	450	}
	451
49346304	452	static int omnia_leds_probe(struct i2c_client *client)
089381b2 MB	453	{
089381b2 MB	454	struct device *dev = &client->dev;
122d57e2	455	struct device_node *np = dev_of_node(dev);
089381b2 MB	456	struct omnia_leds *leds;
	457	struct omnia_led *led;
	458	int ret, count;
	459
	460	count = of_get_available_child_count(np);
	461	if (!count) {
	462	dev_err(dev, "LEDs are not defined in device tree!\n");
	463	return -ENODEV;
	464	} else if (count > OMNIA_BOARD_LEDS) {
	465	dev_err(dev, "Too many LEDs defined in device tree!\n");
	466	return -EINVAL;
	467	}
	468
	469	leds = devm_kzalloc(dev, struct_size(leds, leds, count), GFP_KERNEL);
	470	if (!leds)
	471	return -ENOMEM;
	472
	473	leds->client = client;
	474	i2c_set_clientdata(client, leds);
	475
43e9082f MB	476	ret = omnia_mcu_get_features(client);
	477	if (ret < 0) {
	478	dev_err(dev, "Cannot determine MCU supported features: %d\n",
	479	ret);
	480	return ret;
	481	}
	482
	483	leds->has_gamma_correction = ret & FEAT_LED_GAMMA_CORRECTION;
	484	if (!leds->has_gamma_correction) {
	485	dev_info(dev,
	486	"Your board's MCU firmware does not support the LED gamma correction feature.\n");
	487	dev_info(dev,
	488	"Consider upgrading MCU firmware with the omnia-mcutool utility.\n");
	489	}
	490
089381b2 MB	491	mutex_init(&leds->lock);
089381b2 MB	492
cbd6954f MB	493	ret = devm_led_trigger_register(dev, &omnia_hw_trigger);
	494	if (ret < 0) {
	495	dev_err(dev, "Cannot register private LED trigger: %d\n", ret);
	496	return ret;
	497	}
	498
089381b2	499	led = &leds->leds[0];
122d57e2	500	for_each_available_child_of_node_scoped(np, child) {
089381b2	501	ret = omnia_led_register(client, led, child);
122d57e2	502	if (ret < 0)
089381b2 MB	503	return ret;
	504
	505	led += ret;
	506	}
	507
089381b2 MB	508	return 0;
	509	}
	510
ed5c2f5f	511	static void omnia_leds_remove(struct i2c_client *client)
089381b2	512	{
493d2e43	513	u8 buf[5];
089381b2 MB	514
089381b2 MB	515	/* put all LEDs into default (HW triggered) mode */
6de283b9 MB	516	omnia_cmd_write_u8(client, CMD_LED_MODE,
6de283b9 MB	517	CMD_LED_MODE_LED(OMNIA_BOARD_LEDS));
089381b2 MB	518
089381b2 MB	519	/* set all LEDs color to [255, 255, 255] */
493d2e43 MB	520	buf[0] = CMD_LED_COLOR;
	521	buf[1] = OMNIA_BOARD_LEDS;
	522	buf[2] = 255;
	523	buf[3] = 255;
	524	buf[4] = 255;
089381b2 MB	525
089381b2 MB	526	i2c_master_send(client, buf, 5);
089381b2 MB	527	}
	528
	529	static const struct of_device_id of_omnia_leds_match[] = {
	530	{ .compatible = "cznic,turris-omnia-leds", },
	531	{},
	532	};
64c38866	533	MODULE_DEVICE_TABLE(of, of_omnia_leds_match);
089381b2 MB	534
089381b2 MB	535	static const struct i2c_device_id omnia_id[] = {
c0e3d2be	536	{ "omnia" },
089381b2 MB	537	{ }
089381b2 MB	538	};
9d0150db	539	MODULE_DEVICE_TABLE(i2c, omnia_id);
089381b2 MB	540
089381b2 MB	541	static struct i2c_driver omnia_leds_driver = {
d9ff8a8e	542	.probe = omnia_leds_probe,
089381b2 MB	543	.remove = omnia_leds_remove,
	544	.id_table = omnia_id,
	545	.driver = {
	546	.name = "leds-turris-omnia",
	547	.of_match_table = of_omnia_leds_match,
a01633cd	548	.dev_groups = omnia_led_controller_groups,
089381b2 MB	549	},
	550	};
	551
	552	module_i2c_driver(omnia_leds_driver);
	553
b37c3848	554	MODULE_AUTHOR("Marek Behun <kabel@kernel.org>");
089381b2 MB	555	MODULE_DESCRIPTION("CZ.NIC's Turris Omnia LEDs");
089381b2 MB	556	MODULE_LICENSE("GPL v2");