// SPDX-License-Identifier: GPL-2.0-only

  /*
   * Copyright 2011 bct electronic GmbH

   * Copyright 2013 Qtechnology/AS

   *
   * Author: Peter Meerwald <p.meerwald@bct-electronic.com>

   * Author: Ricardo Ribalda <ribalda@kernel.org>

   *
   * Based on leds-pca955x.c
   *

   * LED driver for the PCA9633 I2C LED driver (7-bit slave address 0x62)

   * LED driver for the PCA9634/5 I2C LED driver (7-bit slave address set by hw.)

   *

   * Note that hardware blinking violates the leds infrastructure driver
   * interface since the hardware only supports blinking all LEDs with the
   * same delay_on/delay_off rates.  That is, only the LEDs that are set to
   * blink will actually blink but all LEDs that are set to blink will blink
   * in identical fashion.  The delay_on/delay_off values of the last LED
   * that is set to blink will be used for all of the blinking LEDs.
   * Hardware blinking is disabled by default but can be enabled by setting

   * the 'blink_type' member in the platform_data struct to 'PCA963X_HW_BLINK'

   * or by adding the 'nxp,hw-blink' property to the DTS.

   */
  
  #include <linux/module.h>
  #include <linux/delay.h>
  #include <linux/string.h>
  #include <linux/ctype.h>
  #include <linux/leds.h>
  #include <linux/err.h>
  #include <linux/i2c.h>

  #include <linux/property.h>

  #include <linux/slab.h>

  #include <linux/of.h>

  
  /* LED select registers determine the source that drives LED outputs */

  #define PCA963X_LED_OFF		0x0	/* LED driver off */
  #define PCA963X_LED_ON		0x1	/* LED driver on */
  #define PCA963X_LED_PWM		0x2	/* Controlled through PWM */
  #define PCA963X_LED_GRP_PWM	0x3	/* Controlled through PWM/GRPPWM */

  #define PCA963X_MODE2_OUTDRV	0x04	/* Open-drain or totem pole */
  #define PCA963X_MODE2_INVRT	0x10	/* Normal or inverted direction */

  #define PCA963X_MODE2_DMBLNK	0x20	/* Enable blinking */

  #define PCA963X_MODE1		0x00
  #define PCA963X_MODE2		0x01
  #define PCA963X_PWM_BASE	0x02

  enum pca963x_type {

  	pca9633,
  	pca9634,

  	pca9635,

  };

  struct pca963x_chipdef {

  	u8			grppwm;
  	u8			grpfreq;
  	u8			ledout_base;
  	int			n_leds;

  	unsigned int		scaling;

  };

  static struct pca963x_chipdef pca963x_chipdefs[] = {

  	[pca9633] = {
  		.grppwm		= 0x6,
  		.grpfreq	= 0x7,
  		.ledout_base	= 0x8,
  		.n_leds		= 4,
  	},
  	[pca9634] = {
  		.grppwm		= 0xa,
  		.grpfreq	= 0xb,
  		.ledout_base	= 0xc,
  		.n_leds		= 8,
  	},

  	[pca9635] = {
  		.grppwm		= 0x12,
  		.grpfreq	= 0x13,
  		.ledout_base	= 0x14,
  		.n_leds		= 16,
  	},

  };

  /* Total blink period in milliseconds */

  #define PCA963X_BLINK_PERIOD_MIN	42
  #define PCA963X_BLINK_PERIOD_MAX	10667

  static const struct i2c_device_id pca963x_id[] = {

  	{ "pca9632", pca9633 },
  	{ "pca9633", pca9633 },
  	{ "pca9634", pca9634 },

  	{ "pca9635", pca9635 },

  	{ }
  };

  MODULE_DEVICE_TABLE(i2c, pca963x_id);

  struct pca963x;

  struct pca963x_led {
  	struct pca963x *chip;

  	struct led_classdev led_cdev;

  	int led_num; /* 0 .. 15 potentially */

  	u8 gdc;
  	u8 gfrq;

  };

  struct pca963x {
  	struct pca963x_chipdef *chipdef;
  	struct mutex mutex;
  	struct i2c_client *client;
  	unsigned long leds_on;
  	struct pca963x_led leds[];
  };

  static int pca963x_brightness(struct pca963x_led *led,

  			      enum led_brightness brightness)

  {

  	struct i2c_client *client = led->chip->client;
  	struct pca963x_chipdef *chipdef = led->chip->chipdef;

  	u8 ledout_addr, ledout, mask, val;
  	int shift;

  	int ret;

  	ledout_addr = chipdef->ledout_base + (led->led_num / 4);
  	shift = 2 * (led->led_num % 4);

  	mask = 0x3 << shift;
  	ledout = i2c_smbus_read_byte_data(client, ledout_addr);

  	switch (brightness) {

  	case LED_FULL:

  		val = (ledout & ~mask) | (PCA963X_LED_ON << shift);
  		ret = i2c_smbus_write_byte_data(client, ledout_addr, val);

  		break;
  	case LED_OFF:

  		val = ledout & ~mask;
  		ret = i2c_smbus_write_byte_data(client, ledout_addr, val);

  		break;
  	default:

  		ret = i2c_smbus_write_byte_data(client,
  						PCA963X_PWM_BASE +

  						led->led_num,

  						brightness);

  		if (ret < 0)

  			return ret;

  
  		val = (ledout & ~mask) | (PCA963X_LED_PWM << shift);
  		ret = i2c_smbus_write_byte_data(client, ledout_addr, val);

  		break;
  	}

  	return ret;

  }

  static void pca963x_blink(struct pca963x_led *led)

  {

  	struct i2c_client *client = led->chip->client;
  	struct pca963x_chipdef *chipdef = led->chip->chipdef;

  	u8 ledout_addr, ledout, mask, val, mode2;
  	int shift;

  	ledout_addr = chipdef->ledout_base + (led->led_num / 4);
  	shift = 2 * (led->led_num % 4);

  	mask = 0x3 << shift;
  	mode2 = i2c_smbus_read_byte_data(client, PCA963X_MODE2);

  	i2c_smbus_write_byte_data(client, chipdef->grppwm, led->gdc);

  	i2c_smbus_write_byte_data(client, chipdef->grpfreq, led->gfrq);

  	if (!(mode2 & PCA963X_MODE2_DMBLNK))

  		i2c_smbus_write_byte_data(client, PCA963X_MODE2,
  					  mode2 | PCA963X_MODE2_DMBLNK);

  	mutex_lock(&led->chip->mutex);

  
  	ledout = i2c_smbus_read_byte_data(client, ledout_addr);
  	if ((ledout & mask) != (PCA963X_LED_GRP_PWM << shift)) {
  		val = (ledout & ~mask) | (PCA963X_LED_GRP_PWM << shift);
  		i2c_smbus_write_byte_data(client, ledout_addr, val);
  	}

  	mutex_unlock(&led->chip->mutex);

  }

  static int pca963x_power_state(struct pca963x_led *led)

  {

  	struct i2c_client *client = led->chip->client;
  	unsigned long *leds_on = &led->chip->leds_on;

  	unsigned long cached_leds = *leds_on;

  	if (led->led_cdev.brightness)
  		set_bit(led->led_num, leds_on);

  	else

  		clear_bit(led->led_num, leds_on);

  
  	if (!(*leds_on) != !cached_leds)

  		return i2c_smbus_write_byte_data(client, PCA963X_MODE1,
  						 *leds_on ? 0 : BIT(4));

  
  	return 0;
  }

  static int pca963x_led_set(struct led_classdev *led_cdev,

  			   enum led_brightness value)

  {

  	struct pca963x_led *led;

  	int ret;

  	led = container_of(led_cdev, struct pca963x_led, led_cdev);

  	mutex_lock(&led->chip->mutex);

  	ret = pca963x_brightness(led, value);

  	if (ret < 0)
  		goto unlock;

  	ret = pca963x_power_state(led);

  
  unlock:

  	mutex_unlock(&led->chip->mutex);

  	return ret;

  }

  static unsigned int pca963x_period_scale(struct pca963x_led *led,

  					 unsigned int val)

  {

  	unsigned int scaling = led->chip->chipdef->scaling;

  
  	return scaling ? DIV_ROUND_CLOSEST(val * scaling, 1000) : val;
  }

  static int pca963x_blink_set(struct led_classdev *led_cdev,

  			     unsigned long *delay_on, unsigned long *delay_off)

  {

  	unsigned long time_on, time_off, period;

  	struct pca963x_led *led;

  	u8 gdc, gfrq;

  	led = container_of(led_cdev, struct pca963x_led, led_cdev);

  
  	time_on = *delay_on;
  	time_off = *delay_off;
  
  	/* If both zero, pick reasonable defaults of 500ms each */
  	if (!time_on && !time_off) {
  		time_on = 500;
  		time_off = 500;
  	}

  	period = pca963x_period_scale(led, time_on + time_off);

  
  	/* If period not supported by hardware, default to someting sane. */

  	if ((period < PCA963X_BLINK_PERIOD_MIN) ||
  	    (period > PCA963X_BLINK_PERIOD_MAX)) {

  		time_on = 500;
  		time_off = 500;

  		period = pca963x_period_scale(led, 1000);

  	}
  
  	/*
  	 * From manual: duty cycle = (GDC / 256) ->
  	 *	(time_on / period) = (GDC / 256) ->
  	 *		GDC = ((time_on * 256) / period)
  	 */

  	gdc = (pca963x_period_scale(led, time_on) * 256) / period;

  
  	/*
  	 * From manual: period = ((GFRQ + 1) / 24) in seconds.
  	 * So, period (in ms) = (((GFRQ + 1) / 24) * 1000) ->
  	 *		GFRQ = ((period * 24 / 1000) - 1)
  	 */
  	gfrq = (period * 24 / 1000) - 1;

  	led->gdc = gdc;
  	led->gfrq = gfrq;

  	pca963x_blink(led);

  
  	*delay_on = time_on;
  	*delay_off = time_off;
  
  	return 0;
  }

  static int pca963x_register_leds(struct i2c_client *client,
  				 struct pca963x *chip)

  {

  	struct pca963x_chipdef *chipdef = chip->chipdef;
  	struct pca963x_led *led = chip->leds;
  	struct device *dev = &client->dev;

  	struct fwnode_handle *child;

  	bool hw_blink;
  	s32 mode2;
  	u32 reg;
  	int ret;

  	if (device_property_read_u32(dev, "nxp,period-scale",
  				     &chipdef->scaling))
  		chipdef->scaling = 1000;

  	hw_blink = device_property_read_bool(dev, "nxp,hw-blink");

  	mode2 = i2c_smbus_read_byte_data(client, PCA963X_MODE2);
  	if (mode2 < 0)
  		return mode2;

  	/* default to open-drain unless totem pole (push-pull) is specified */
  	if (device_property_read_bool(dev, "nxp,totem-pole"))
  		mode2 |= PCA963X_MODE2_OUTDRV;
  	else
  		mode2 &= ~PCA963X_MODE2_OUTDRV;

  	/* default to non-inverted output, unless inverted is specified */
  	if (device_property_read_bool(dev, "nxp,inverted-out"))
  		mode2 |= PCA963X_MODE2_INVRT;
  	else
  		mode2 &= ~PCA963X_MODE2_INVRT;

  	ret = i2c_smbus_write_byte_data(client, PCA963X_MODE2, mode2);
  	if (ret < 0)
  		return ret;

  	device_for_each_child_node(dev, child) {

  		struct led_init_data init_data = {};
  		char default_label[32];

  		ret = fwnode_property_read_u32(child, "reg", &reg);
  		if (ret || reg >= chipdef->n_leds) {
  			dev_err(dev, "Invalid 'reg' property for node %pfw
  ",
  				child);
  			ret = -EINVAL;
  			goto err;
  		}

  		led->led_num = reg;
  		led->chip = chip;

  		led->led_cdev.brightness_set_blocking = pca963x_led_set;
  		if (hw_blink)
  			led->led_cdev.blink_set = pca963x_blink_set;

  		init_data.fwnode = child;
  		/* for backwards compatibility */
  		init_data.devicename = "pca963x";
  		snprintf(default_label, sizeof(default_label), "%d:%.2x:%u",
  			 client->adapter->nr, client->addr, reg);
  		init_data.default_label = default_label;
  
  		ret = devm_led_classdev_register_ext(dev, &led->led_cdev,
  						     &init_data);

  		if (ret) {
  			dev_err(dev, "Failed to register LED for node %pfw
  ",
  				child);
  			goto err;
  		}

  		++led;
  	}

  	return 0;
  err:
  	fwnode_handle_put(child);
  	return ret;

  }

  static const struct of_device_id of_pca963x_match[] = {

  	{ .compatible = "nxp,pca9632", },
  	{ .compatible = "nxp,pca9633", },
  	{ .compatible = "nxp,pca9634", },

  	{ .compatible = "nxp,pca9635", },

  	{},
  };

  MODULE_DEVICE_TABLE(of, of_pca963x_match);

  static int pca963x_probe(struct i2c_client *client,

  			 const struct i2c_device_id *id)

  {

  	struct device *dev = &client->dev;

  	struct pca963x_chipdef *chipdef;

  	struct pca963x *chip;

  	int i, count;

  	chipdef = &pca963x_chipdefs[id->driver_data];

  	count = device_get_child_node_count(dev);
  	if (!count || count > chipdef->n_leds) {
  		dev_err(dev, "Node %pfw must define between 1 and %d LEDs
  ",
  			dev_fwnode(dev), chipdef->n_leds);

  		return -EINVAL;

  	}

  	chip = devm_kzalloc(dev, struct_size(chip, leds, count), GFP_KERNEL);

  	if (!chip)

  		return -ENOMEM;

  	i2c_set_clientdata(client, chip);

  	mutex_init(&chip->mutex);
  	chip->chipdef = chipdef;
  	chip->client = client;

  
  	/* Turn off LEDs by default*/

  	for (i = 0; i < chipdef->n_leds / 4; i++)
  		i2c_smbus_write_byte_data(client, chipdef->ledout_base + i, 0x00);

  	/* Disable LED all-call address, and power down initially */
  	i2c_smbus_write_byte_data(client, PCA963X_MODE1, BIT(4));

  	return pca963x_register_leds(client, chip);

  }

  static struct i2c_driver pca963x_driver = {

  	.driver = {

  		.name	= "leds-pca963x",

  		.of_match_table = of_pca963x_match,

  	},

  	.probe	= pca963x_probe,

  	.id_table = pca963x_id,

  };

  module_i2c_driver(pca963x_driver);

  
  MODULE_AUTHOR("Peter Meerwald <p.meerwald@bct-electronic.com>");

  MODULE_DESCRIPTION("PCA963X LED driver");

  MODULE_LICENSE("GPL v2");