[linux-block.git] / drivers / leds / leds-pca955x.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright 2007-2008 Extreme Engineering Solutions, Inc.
 *
 * Author: Nate Case <ncase@xes-inc.com>
 *
 * LED driver for various PCA955x I2C LED drivers
 *
 * Supported devices:
 *
 *	Device		Description		7-bit slave address
 *	------		-----------		-------------------
 *	PCA9550		2-bit driver		0x60 .. 0x61
 *	PCA9551		8-bit driver		0x60 .. 0x67
 *	PCA9552		16-bit driver		0x60 .. 0x67
 *	PCA9553/01	4-bit driver		0x62
 *	PCA9553/02	4-bit driver		0x63
 *
 * Philips PCA955x LED driver chips follow a register map as shown below:
 *
 *	Control Register		Description
 *	----------------		-----------
 *	0x0				Input register 0
 *					..
 *	NUM_INPUT_REGS - 1		Last Input register X
 *
 *	NUM_INPUT_REGS			Frequency prescaler 0
 *	NUM_INPUT_REGS + 1		PWM register 0
 *	NUM_INPUT_REGS + 2		Frequency prescaler 1
 *	NUM_INPUT_REGS + 3		PWM register 1
 *
 *	NUM_INPUT_REGS + 4		LED selector 0
 *	NUM_INPUT_REGS + 4
 *	    + NUM_LED_REGS - 1		Last LED selector
 *
 *  where NUM_INPUT_REGS and NUM_LED_REGS vary depending on how many
 *  bits the chip supports.
 */

#include <linux/ctype.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/gpio/driver.h>
#include <linux/i2c.h>
#include <linux/leds.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/property.h>
#include <linux/slab.h>
#include <linux/string.h>

#include <dt-bindings/leds/leds-pca955x.h>

/* LED select registers determine the source that drives LED outputs */
#define PCA955X_LS_LED_ON	0x0	/* Output LOW */
#define PCA955X_LS_LED_OFF	0x1	/* Output HI-Z */
#define PCA955X_LS_BLINK0	0x2	/* Blink at PWM0 rate */
#define PCA955X_LS_BLINK1	0x3	/* Blink at PWM1 rate */

#define PCA955X_GPIO_INPUT	LED_OFF
#define PCA955X_GPIO_HIGH	LED_OFF
#define PCA955X_GPIO_LOW	LED_FULL

enum pca955x_type {
	pca9550,
	pca9551,
	pca9552,
	ibm_pca9552,
	pca9553,
};

struct pca955x_chipdef {
	int			bits;
	u8			slv_addr;	/* 7-bit slave address mask */
	int			slv_addr_shift;	/* Number of bits to ignore */
};

static struct pca955x_chipdef pca955x_chipdefs[] = {
	[pca9550] = {
		.bits		= 2,
		.slv_addr	= /* 110000x */ 0x60,
		.slv_addr_shift	= 1,
	},
	[pca9551] = {
		.bits		= 8,
		.slv_addr	= /* 1100xxx */ 0x60,
		.slv_addr_shift	= 3,
	},
	[pca9552] = {
		.bits		= 16,
		.slv_addr	= /* 1100xxx */ 0x60,
		.slv_addr_shift	= 3,
	},
	[ibm_pca9552] = {
		.bits		= 16,
		.slv_addr	= /* 0110xxx */ 0x30,
		.slv_addr_shift	= 3,
	},
	[pca9553] = {
		.bits		= 4,
		.slv_addr	= /* 110001x */ 0x62,
		.slv_addr_shift	= 1,
	},
};

static const struct i2c_device_id pca955x_id[] = {
	{ "pca9550", pca9550 },
	{ "pca9551", pca9551 },
	{ "pca9552", pca9552 },
	{ "ibm-pca9552", ibm_pca9552 },
	{ "pca9553", pca9553 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, pca955x_id);

struct pca955x {
	struct mutex lock;
	struct pca955x_led *leds;
	struct pca955x_chipdef	*chipdef;
	struct i2c_client	*client;
#ifdef CONFIG_LEDS_PCA955X_GPIO
	struct gpio_chip gpio;
#endif
};

struct pca955x_led {
	struct pca955x	*pca955x;
	struct led_classdev	led_cdev;
	int			led_num;	/* 0 .. 15 potentially */
	char			name[32];
	u32			type;
	const char		*default_trigger;
};

struct pca955x_platform_data {
	struct pca955x_led	*leds;
	int			num_leds;
};

/* 8 bits per input register */
static inline int pca95xx_num_input_regs(int bits)
{
	return (bits + 7) / 8;
}

/* 4 bits per LED selector register */
static inline int pca95xx_num_led_regs(int bits)
{
	return (bits + 3)  / 4;
}

/*
 * Return an LED selector register value based on an existing one, with
 * the appropriate 2-bit state value set for the given LED number (0-3).
 */
static inline u8 pca955x_ledsel(u8 oldval, int led_num, int state)
{
	return (oldval & (~(0x3 << (led_num << 1)))) |
		((state & 0x3) << (led_num << 1));
}

/*
 * Write to frequency prescaler register, used to program the
 * period of the PWM output.  period = (PSCx + 1) / 38
 */
static int pca955x_write_psc(struct i2c_client *client, int n, u8 val)
{
	struct pca955x *pca955x = i2c_get_clientdata(client);
	u8 cmd = pca95xx_num_input_regs(pca955x->chipdef->bits) + (2 * n);
	int ret;

	ret = i2c_smbus_write_byte_data(client, cmd, val);
	if (ret < 0)
		dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n",
			__func__, n, val, ret);
	return ret;
}

/*
 * Write to PWM register, which determines the duty cycle of the
 * output.  LED is OFF when the count is less than the value of this
 * register, and ON when it is greater.  If PWMx == 0, LED is always OFF.
 *
 * Duty cycle is (256 - PWMx) / 256
 */
static int pca955x_write_pwm(struct i2c_client *client, int n, u8 val)
{
	struct pca955x *pca955x = i2c_get_clientdata(client);
	u8 cmd = pca95xx_num_input_regs(pca955x->chipdef->bits) + 1 + (2 * n);
	int ret;

	ret = i2c_smbus_write_byte_data(client, cmd, val);
	if (ret < 0)
		dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n",
			__func__, n, val, ret);
	return ret;
}

/*
 * Write to LED selector register, which determines the source that
 * drives the LED output.
 */
static int pca955x_write_ls(struct i2c_client *client, int n, u8 val)
{
	struct pca955x *pca955x = i2c_get_clientdata(client);
	u8 cmd = pca95xx_num_input_regs(pca955x->chipdef->bits) + 4 + n;
	int ret;

	ret = i2c_smbus_write_byte_data(client, cmd, val);
	if (ret < 0)
		dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n",
			__func__, n, val, ret);
	return ret;
}

/*
 * Read the LED selector register, which determines the source that
 * drives the LED output.
 */
static int pca955x_read_ls(struct i2c_client *client, int n, u8 *val)
{
	struct pca955x *pca955x = i2c_get_clientdata(client);
	u8 cmd = pca95xx_num_input_regs(pca955x->chipdef->bits) + 4 + n;
	int ret;

	ret = i2c_smbus_read_byte_data(client, cmd);
	if (ret < 0) {
		dev_err(&client->dev, "%s: reg 0x%x, err %d\n",
			__func__, n, ret);
		return ret;
	}
	*val = (u8)ret;
	return 0;
}

static int pca955x_read_pwm(struct i2c_client *client, int n, u8 *val)
{
	struct pca955x *pca955x = i2c_get_clientdata(client);
	u8 cmd = pca95xx_num_input_regs(pca955x->chipdef->bits) + 1 + (2 * n);
	int ret;

	ret = i2c_smbus_read_byte_data(client, cmd);
	if (ret < 0) {
		dev_err(&client->dev, "%s: reg 0x%x, err %d\n",
			__func__, n, ret);
		return ret;
	}
	*val = (u8)ret;
	return 0;
}

static enum led_brightness pca955x_led_get(struct led_classdev *led_cdev)
{
	struct pca955x_led *pca955x_led = container_of(led_cdev,
						       struct pca955x_led,
						       led_cdev);
	struct pca955x *pca955x = pca955x_led->pca955x;
	u8 ls, pwm;
	int ret;

	ret = pca955x_read_ls(pca955x->client, pca955x_led->led_num / 4, &ls);
	if (ret)
		return ret;

	ls = (ls >> ((pca955x_led->led_num % 4) << 1)) & 0x3;
	switch (ls) {
	case PCA955X_LS_LED_ON:
		ret = LED_FULL;
		break;
	case PCA955X_LS_LED_OFF:
		ret = LED_OFF;
		break;
	case PCA955X_LS_BLINK0:
		ret = LED_HALF;
		break;
	case PCA955X_LS_BLINK1:
		ret = pca955x_read_pwm(pca955x->client, 1, &pwm);
		if (ret)
			return ret;
		ret = 255 - pwm;
		break;
	}

	return ret;
}

static int pca955x_led_set(struct led_classdev *led_cdev,
			    enum led_brightness value)
{
	struct pca955x_led *pca955x_led;
	struct pca955x *pca955x;
	u8 ls;
	int chip_ls;	/* which LSx to use (0-3 potentially) */
	int ls_led;	/* which set of bits within LSx to use (0-3) */
	int ret;

	pca955x_led = container_of(led_cdev, struct pca955x_led, led_cdev);
	pca955x = pca955x_led->pca955x;

	chip_ls = pca955x_led->led_num / 4;
	ls_led = pca955x_led->led_num % 4;

	mutex_lock(&pca955x->lock);

	ret = pca955x_read_ls(pca955x->client, chip_ls, &ls);
	if (ret)
		goto out;

	switch (value) {
	case LED_FULL:
		ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_LED_ON);
		break;
	case LED_OFF:
		ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_LED_OFF);
		break;
	case LED_HALF:
		ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_BLINK0);
		break;
	default:
		/*
		 * Use PWM1 for all other values.  This has the unwanted
		 * side effect of making all LEDs on the chip share the
		 * same brightness level if set to a value other than
		 * OFF, HALF, or FULL.  But, this is probably better than
		 * just turning off for all other values.
		 */
		ret = pca955x_write_pwm(pca955x->client, 1, 255 - value);
		if (ret)
			goto out;
		ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_BLINK1);
		break;
	}

	ret = pca955x_write_ls(pca955x->client, chip_ls, ls);

out:
	mutex_unlock(&pca955x->lock);

	return ret;
}

#ifdef CONFIG_LEDS_PCA955X_GPIO
/*
 * Read the INPUT register, which contains the state of LEDs.
 */
static int pca955x_read_input(struct i2c_client *client, int n, u8 *val)
{
	int ret = i2c_smbus_read_byte_data(client, n);

	if (ret < 0) {
		dev_err(&client->dev, "%s: reg 0x%x, err %d\n",
			__func__, n, ret);
		return ret;
	}
	*val = (u8)ret;
	return 0;

}

static int pca955x_gpio_request_pin(struct gpio_chip *gc, unsigned int offset)
{
	struct pca955x *pca955x = gpiochip_get_data(gc);
	struct pca955x_led *led = &pca955x->leds[offset];

	if (led->type == PCA955X_TYPE_GPIO)
		return 0;

	return -EBUSY;
}

static int pca955x_set_value(struct gpio_chip *gc, unsigned int offset,
			     int val)
{
	struct pca955x *pca955x = gpiochip_get_data(gc);
	struct pca955x_led *led = &pca955x->leds[offset];

	if (val)
		return pca955x_led_set(&led->led_cdev, PCA955X_GPIO_HIGH);

	return pca955x_led_set(&led->led_cdev, PCA955X_GPIO_LOW);
}

static void pca955x_gpio_set_value(struct gpio_chip *gc, unsigned int offset,
				   int val)
{
	pca955x_set_value(gc, offset, val);
}

static int pca955x_gpio_get_value(struct gpio_chip *gc, unsigned int offset)
{
	struct pca955x *pca955x = gpiochip_get_data(gc);
	struct pca955x_led *led = &pca955x->leds[offset];
	u8 reg = 0;

	/* There is nothing we can do about errors */
	pca955x_read_input(pca955x->client, led->led_num / 8, &reg);

	return !!(reg & (1 << (led->led_num % 8)));
}

static int pca955x_gpio_direction_input(struct gpio_chip *gc,
					unsigned int offset)
{
	struct pca955x *pca955x = gpiochip_get_data(gc);
	struct pca955x_led *led = &pca955x->leds[offset];

	/* To use as input ensure pin is not driven. */
	return pca955x_led_set(&led->led_cdev, PCA955X_GPIO_INPUT);
}

static int pca955x_gpio_direction_output(struct gpio_chip *gc,
					 unsigned int offset, int val)
{
	return pca955x_set_value(gc, offset, val);
}
#endif /* CONFIG_LEDS_PCA955X_GPIO */

static struct pca955x_platform_data *
pca955x_get_pdata(struct i2c_client *client, struct pca955x_chipdef *chip)
{
	struct pca955x_platform_data *pdata;
	struct pca955x_led *led;
	struct fwnode_handle *child;
	int count;

	count = device_get_child_node_count(&client->dev);
	if (!count || count > chip->bits)
		return ERR_PTR(-ENODEV);

	pdata = devm_kzalloc(&client->dev, sizeof(*pdata), GFP_KERNEL);
	if (!pdata)
		return ERR_PTR(-ENOMEM);

	pdata->leds = devm_kcalloc(&client->dev,
				   chip->bits, sizeof(struct pca955x_led),
				   GFP_KERNEL);
	if (!pdata->leds)
		return ERR_PTR(-ENOMEM);

	device_for_each_child_node(&client->dev, child) {
		const char *name;
		u32 reg;
		int res;

		res = fwnode_property_read_u32(child, "reg", &reg);
		if ((res != 0) || (reg >= chip->bits))
			continue;

		res = fwnode_property_read_string(child, "label", &name);
		if ((res != 0) && is_of_node(child))
			name = to_of_node(child)->name;

		led = &pdata->leds[reg];
		snprintf(led->name, sizeof(led->name), "%s", name);

		led->type = PCA955X_TYPE_LED;
		fwnode_property_read_u32(child, "type", &led->type);
		fwnode_property_read_string(child, "linux,default-trigger",
					    &led->default_trigger);
	}

	pdata->num_leds = chip->bits;

	return pdata;
}

static const struct of_device_id of_pca955x_match[] = {
	{ .compatible = "nxp,pca9550", .data = (void *)pca9550 },
	{ .compatible = "nxp,pca9551", .data = (void *)pca9551 },
	{ .compatible = "nxp,pca9552", .data = (void *)pca9552 },
	{ .compatible = "ibm,pca9552", .data = (void *)ibm_pca9552 },
	{ .compatible = "nxp,pca9553", .data = (void *)pca9553 },
	{},
};
MODULE_DEVICE_TABLE(of, of_pca955x_match);

static int pca955x_probe(struct i2c_client *client,
			 const struct i2c_device_id *id)
{
	struct pca955x *pca955x;
	struct pca955x_led *pca955x_led;
	struct pca955x_chipdef *chip;
	struct led_classdev *led;
	struct i2c_adapter *adapter;
	int i, err;
	struct pca955x_platform_data *pdata;
	int ngpios = 0;

	chip = &pca955x_chipdefs[id->driver_data];
	adapter = client->adapter;
	pdata = dev_get_platdata(&client->dev);
	if (!pdata) {
		pdata =	pca955x_get_pdata(client, chip);
		if (IS_ERR(pdata))
			return PTR_ERR(pdata);
	}

	/* Make sure the slave address / chip type combo given is possible */
	if ((client->addr & ~((1 << chip->slv_addr_shift) - 1)) !=
	    chip->slv_addr) {
		dev_err(&client->dev, "invalid slave address %02x\n",
			client->addr);
		return -ENODEV;
	}

	dev_info(&client->dev, "leds-pca955x: Using %s %d-bit LED driver at "
		 "slave address 0x%02x\n", client->name, chip->bits,
		 client->addr);

	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
		return -EIO;

	if (pdata->num_leds != chip->bits) {
		dev_err(&client->dev,
			"board info claims %d LEDs on a %d-bit chip\n",
			pdata->num_leds, chip->bits);
		return -ENODEV;
	}

	pca955x = devm_kzalloc(&client->dev, sizeof(*pca955x), GFP_KERNEL);
	if (!pca955x)
		return -ENOMEM;

	pca955x->leds = devm_kcalloc(&client->dev, chip->bits,
				     sizeof(*pca955x_led), GFP_KERNEL);
	if (!pca955x->leds)
		return -ENOMEM;

	i2c_set_clientdata(client, pca955x);

	mutex_init(&pca955x->lock);
	pca955x->client = client;
	pca955x->chipdef = chip;

	for (i = 0; i < chip->bits; i++) {
		pca955x_led = &pca955x->leds[i];
		pca955x_led->led_num = i;
		pca955x_led->pca955x = pca955x;
		pca955x_led->type = pdata->leds[i].type;

		switch (pca955x_led->type) {
		case PCA955X_TYPE_NONE:
			break;
		case PCA955X_TYPE_GPIO:
			ngpios++;
			break;
		case PCA955X_TYPE_LED:
			/*
			 * Platform data can specify LED names and
			 * default triggers
			 */
			if (pdata->leds[i].name[0] == '\0')
				snprintf(pdata->leds[i].name,
					 sizeof(pdata->leds[i].name), "%d", i);

			snprintf(pca955x_led->name, sizeof(pca955x_led->name),
				 "pca955x:%s", pdata->leds[i].name);

			led = &pca955x_led->led_cdev;
			if (pdata->leds[i].default_trigger)
				led->default_trigger =
					pdata->leds[i].default_trigger;

			led->name = pca955x_led->name;
			led->brightness_set_blocking = pca955x_led_set;
			led->brightness_get = pca955x_led_get;

			err = devm_led_classdev_register(&client->dev, led);
			if (err)
				return err;

			/* Turn off LED */
			err = pca955x_led_set(led, LED_OFF);
			if (err)
				return err;
		}
	}

	/* PWM0 is used for half brightness or 50% duty cycle */
	err = pca955x_write_pwm(client, 0, 255 - LED_HALF);
	if (err)
		return err;

	/* PWM1 is used for variable brightness, default to OFF */
	err = pca955x_write_pwm(client, 1, 0);
	if (err)
		return err;

	/* Set to fast frequency so we do not see flashing */
	err = pca955x_write_psc(client, 0, 0);
	if (err)
		return err;
	err = pca955x_write_psc(client, 1, 0);
	if (err)
		return err;

#ifdef CONFIG_LEDS_PCA955X_GPIO
	if (ngpios) {
		pca955x->gpio.label = "gpio-pca955x";
		pca955x->gpio.direction_input = pca955x_gpio_direction_input;
		pca955x->gpio.direction_output = pca955x_gpio_direction_output;
		pca955x->gpio.set = pca955x_gpio_set_value;
		pca955x->gpio.get = pca955x_gpio_get_value;
		pca955x->gpio.request = pca955x_gpio_request_pin;
		pca955x->gpio.can_sleep = 1;
		pca955x->gpio.base = -1;
		pca955x->gpio.ngpio = ngpios;
		pca955x->gpio.parent = &client->dev;
		pca955x->gpio.owner = THIS_MODULE;

		err = devm_gpiochip_add_data(&client->dev, &pca955x->gpio,
					     pca955x);
		if (err) {
			/* Use data->gpio.dev as a flag for freeing gpiochip */
			pca955x->gpio.parent = NULL;
			dev_warn(&client->dev, "could not add gpiochip\n");
			return err;
		}
		dev_info(&client->dev, "gpios %i...%i\n",
			 pca955x->gpio.base, pca955x->gpio.base +
			 pca955x->gpio.ngpio - 1);
	}
#endif

	return 0;
}

static struct i2c_driver pca955x_driver = {
	.driver = {
		.name	= "leds-pca955x",
		.of_match_table = of_pca955x_match,
	},
	.probe	= pca955x_probe,
	.id_table = pca955x_id,
};

module_i2c_driver(pca955x_driver);

MODULE_AUTHOR("Nate Case <ncase@xes-inc.com>");
MODULE_DESCRIPTION("PCA955x LED driver");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
36edc939	1	// SPDX-License-Identifier: GPL-2.0-only
f46e9203 NC	2	/*
	3	* Copyright 2007-2008 Extreme Engineering Solutions, Inc.
	4	*
	5	* Author: Nate Case <ncase@xes-inc.com>
	6	*
f46e9203 NC	7	* LED driver for various PCA955x I2C LED drivers
	8	*
	9	* Supported devices:
	10	*
	11	* Device Description 7-bit slave address
	12	* ------ ----------- -------------------
	13	* PCA9550 2-bit driver 0x60 .. 0x61
	14	* PCA9551 8-bit driver 0x60 .. 0x67
	15	* PCA9552 16-bit driver 0x60 .. 0x67
	16	* PCA9553/01 4-bit driver 0x62
	17	* PCA9553/02 4-bit driver 0x63
	18	*
	19	* Philips PCA955x LED driver chips follow a register map as shown below:
	20	*
	21	* Control Register Description
	22	* ---------------- -----------
	23	* 0x0 Input register 0
	24	* ..
	25	* NUM_INPUT_REGS - 1 Last Input register X
	26	*
	27	* NUM_INPUT_REGS Frequency prescaler 0
	28	* NUM_INPUT_REGS + 1 PWM register 0
	29	* NUM_INPUT_REGS + 2 Frequency prescaler 1
	30	* NUM_INPUT_REGS + 3 PWM register 1
	31	*
	32	* NUM_INPUT_REGS + 4 LED selector 0
	33	* NUM_INPUT_REGS + 4
	34	* + NUM_LED_REGS - 1 Last LED selector
	35	*
	36	* where NUM_INPUT_REGS and NUM_LED_REGS vary depending on how many
	37	* bits the chip supports.
	38	*/
	39
f46e9203	40	#include <linux/ctype.h>
ed1f4b96	41	#include <linux/delay.h>
f46e9203	42	#include <linux/err.h>
0987c7df	43	#include <linux/gpio/driver.h>
f46e9203	44	#include <linux/i2c.h>
ed1f4b96 CLG	45	#include <linux/leds.h>
ed1f4b96 CLG	46	#include <linux/module.h>
ed1f4b96	47	#include <linux/of.h>
967f69de	48	#include <linux/property.h>
5a0e3ad6	49	#include <linux/slab.h>
ed1f4b96	50	#include <linux/string.h>
f46e9203	51
561099a1 CLG	52	#include <dt-bindings/leds/leds-pca955x.h>
561099a1 CLG	53
f46e9203 NC	54	/* LED select registers determine the source that drives LED outputs */
	55	#define PCA955X_LS_LED_ON 0x0 /* Output LOW */
	56	#define PCA955X_LS_LED_OFF 0x1 /* Output HI-Z */
	57	#define PCA955X_LS_BLINK0 0x2 /* Blink at PWM0 rate */
	58	#define PCA955X_LS_BLINK1 0x3 /* Blink at PWM1 rate */
	59
52ca7d0f AJ	60	#define PCA955X_GPIO_INPUT LED_OFF
	61	#define PCA955X_GPIO_HIGH LED_OFF
	62	#define PCA955X_GPIO_LOW LED_FULL
	63
f46e9203 NC	64	enum pca955x_type {
	65	pca9550,
	66	pca9551,
	67	pca9552,
46de3adb	68	ibm_pca9552,
f46e9203 NC	69	pca9553,
	70	};
	71
	72	struct pca955x_chipdef {
	73	int bits;
	74	u8 slv_addr; /* 7-bit slave address mask */
	75	int slv_addr_shift; /* Number of bits to ignore */
	76	};
	77
	78	static struct pca955x_chipdef pca955x_chipdefs[] = {
	79	[pca9550] = {
	80	.bits = 2,
	81	.slv_addr = /* 110000x */ 0x60,
	82	.slv_addr_shift = 1,
	83	},
	84	[pca9551] = {
	85	.bits = 8,
	86	.slv_addr = /* 1100xxx */ 0x60,
	87	.slv_addr_shift = 3,
	88	},
	89	[pca9552] = {
	90	.bits = 16,
	91	.slv_addr = /* 1100xxx */ 0x60,
	92	.slv_addr_shift = 3,
	93	},
46de3adb EJ	94	[ibm_pca9552] = {
	95	.bits = 16,
	96	.slv_addr = /* 0110xxx */ 0x30,
	97	.slv_addr_shift = 3,
	98	},
f46e9203 NC	99	[pca9553] = {
	100	.bits = 4,
	101	.slv_addr = /* 110001x */ 0x62,
	102	.slv_addr_shift = 1,
	103	},
	104	};
	105
	106	static const struct i2c_device_id pca955x_id[] = {
	107	{ "pca9550", pca9550 },
	108	{ "pca9551", pca9551 },
	109	{ "pca9552", pca9552 },
46de3adb	110	{ "ibm-pca9552", ibm_pca9552 },
f46e9203 NC	111	{ "pca9553", pca9553 },
	112	{ }
	113	};
	114	MODULE_DEVICE_TABLE(i2c, pca955x_id);
	115
e7e11d8b AS	116	struct pca955x {
	117	struct mutex lock;
	118	struct pca955x_led *leds;
f46e9203 NC	119	struct pca955x_chipdef *chipdef;
f46e9203 NC	120	struct i2c_client *client;
561099a1 CLG	121	#ifdef CONFIG_LEDS_PCA955X_GPIO
	122	struct gpio_chip gpio;
	123	#endif
e7e11d8b AS	124	};
	125
	126	struct pca955x_led {
	127	struct pca955x *pca955x;
f46e9203 NC	128	struct led_classdev led_cdev;
	129	int led_num; /* 0 .. 15 potentially */
	130	char name[32];
561099a1	131	u32 type;
ed1f4b96 CLG	132	const char *default_trigger;
	133	};
	134
	135	struct pca955x_platform_data {
	136	struct pca955x_led *leds;
	137	int num_leds;
f46e9203 NC	138	};
	139
	140	/* 8 bits per input register */
	141	static inline int pca95xx_num_input_regs(int bits)
	142	{
	143	return (bits + 7) / 8;
	144	}
	145
	146	/* 4 bits per LED selector register */
	147	static inline int pca95xx_num_led_regs(int bits)
	148	{
	149	return (bits + 3) / 4;
	150	}
	151
	152	/*
	153	* Return an LED selector register value based on an existing one, with
	154	* the appropriate 2-bit state value set for the given LED number (0-3).
	155	*/
	156	static inline u8 pca955x_ledsel(u8 oldval, int led_num, int state)
	157	{
	158	return (oldval & (~(0x3 << (led_num << 1)))) \|
	159	((state & 0x3) << (led_num << 1));
	160	}
	161
	162	/*
	163	* Write to frequency prescaler register, used to program the
	164	* period of the PWM output. period = (PSCx + 1) / 38
	165	*/
1591caf2	166	static int pca955x_write_psc(struct i2c_client *client, int n, u8 val)
f46e9203	167	{
e7e11d8b	168	struct pca955x *pca955x = i2c_get_clientdata(client);
2420ae02	169	u8 cmd = pca95xx_num_input_regs(pca955x->chipdef->bits) + (2 * n);
1591caf2	170	int ret;
f46e9203	171
2420ae02	172	ret = i2c_smbus_write_byte_data(client, cmd, val);
1591caf2 CLG	173	if (ret < 0)
	174	dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n",
	175	__func__, n, val, ret);
	176	return ret;
f46e9203 NC	177	}
	178
	179	/*
	180	* Write to PWM register, which determines the duty cycle of the
	181	* output. LED is OFF when the count is less than the value of this
	182	* register, and ON when it is greater. If PWMx == 0, LED is always OFF.
	183	*
	184	* Duty cycle is (256 - PWMx) / 256
	185	*/
1591caf2	186	static int pca955x_write_pwm(struct i2c_client *client, int n, u8 val)
f46e9203	187	{
e7e11d8b	188	struct pca955x *pca955x = i2c_get_clientdata(client);
2420ae02	189	u8 cmd = pca95xx_num_input_regs(pca955x->chipdef->bits) + 1 + (2 * n);
1591caf2	190	int ret;
f46e9203	191
2420ae02	192	ret = i2c_smbus_write_byte_data(client, cmd, val);
1591caf2 CLG	193	if (ret < 0)
	194	dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n",
	195	__func__, n, val, ret);
	196	return ret;
f46e9203 NC	197	}
	198
	199	/*
	200	* Write to LED selector register, which determines the source that
	201	* drives the LED output.
	202	*/
1591caf2	203	static int pca955x_write_ls(struct i2c_client *client, int n, u8 val)
f46e9203	204	{
e7e11d8b	205	struct pca955x *pca955x = i2c_get_clientdata(client);
2420ae02	206	u8 cmd = pca95xx_num_input_regs(pca955x->chipdef->bits) + 4 + n;
1591caf2	207	int ret;
f46e9203	208
2420ae02	209	ret = i2c_smbus_write_byte_data(client, cmd, val);
1591caf2 CLG	210	if (ret < 0)
	211	dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n",
	212	__func__, n, val, ret);
	213	return ret;
f46e9203 NC	214	}
	215
	216	/*
	217	* Read the LED selector register, which determines the source that
	218	* drives the LED output.
	219	*/
1591caf2	220	static int pca955x_read_ls(struct i2c_client client, int n, u8 val)
f46e9203	221	{
e7e11d8b	222	struct pca955x *pca955x = i2c_get_clientdata(client);
2420ae02	223	u8 cmd = pca95xx_num_input_regs(pca955x->chipdef->bits) + 4 + n;
1591caf2	224	int ret;
f46e9203	225
2420ae02	226	ret = i2c_smbus_read_byte_data(client, cmd);
1591caf2 CLG	227	if (ret < 0) {
	228	dev_err(&client->dev, "%s: reg 0x%x, err %d\n",
	229	__func__, n, ret);
	230	return ret;
	231	}
	232	*val = (u8)ret;
	233	return 0;
f46e9203 NC	234	}
f46e9203 NC	235
7086625f EJ	236	static int pca955x_read_pwm(struct i2c_client client, int n, u8 val)
	237	{
	238	struct pca955x *pca955x = i2c_get_clientdata(client);
	239	u8 cmd = pca95xx_num_input_regs(pca955x->chipdef->bits) + 1 + (2 * n);
	240	int ret;
	241
	242	ret = i2c_smbus_read_byte_data(client, cmd);
	243	if (ret < 0) {
	244	dev_err(&client->dev, "%s: reg 0x%x, err %d\n",
	245	__func__, n, ret);
	246	return ret;
	247	}
	248	*val = (u8)ret;
	249	return 0;
	250	}
	251
	252	static enum led_brightness pca955x_led_get(struct led_classdev *led_cdev)
	253	{
	254	struct pca955x_led *pca955x_led = container_of(led_cdev,
	255	struct pca955x_led,
	256	led_cdev);
	257	struct pca955x *pca955x = pca955x_led->pca955x;
	258	u8 ls, pwm;
	259	int ret;
	260
	261	ret = pca955x_read_ls(pca955x->client, pca955x_led->led_num / 4, &ls);
	262	if (ret)
	263	return ret;
	264
	265	ls = (ls >> ((pca955x_led->led_num % 4) << 1)) & 0x3;
	266	switch (ls) {
	267	case PCA955X_LS_LED_ON:
	268	ret = LED_FULL;
	269	break;
	270	case PCA955X_LS_LED_OFF:
	271	ret = LED_OFF;
	272	break;
	273	case PCA955X_LS_BLINK0:
	274	ret = LED_HALF;
	275	break;
	276	case PCA955X_LS_BLINK1:
	277	ret = pca955x_read_pwm(pca955x->client, 1, &pwm);
	278	if (ret)
	279	return ret;
	280	ret = 255 - pwm;
	281	break;
	282	}
	283
	284	return ret;
	285	}
	286
c3482b82 AL	287	static int pca955x_led_set(struct led_classdev *led_cdev,
c3482b82 AL	288	enum led_brightness value)
f46e9203	289	{
e7e11d8b AS	290	struct pca955x_led *pca955x_led;
e7e11d8b AS	291	struct pca955x *pca955x;
f46e9203 NC	292	u8 ls;
	293	int chip_ls; /* which LSx to use (0-3 potentially) */
	294	int ls_led; /* which set of bits within LSx to use (0-3) */
1591caf2	295	int ret;
f46e9203	296
c3482b82	297	pca955x_led = container_of(led_cdev, struct pca955x_led, led_cdev);
e7e11d8b AS	298	pca955x = pca955x_led->pca955x;
	299
	300	chip_ls = pca955x_led->led_num / 4;
	301	ls_led = pca955x_led->led_num % 4;
	302
	303	mutex_lock(&pca955x->lock);
f46e9203	304
1591caf2 CLG	305	ret = pca955x_read_ls(pca955x->client, chip_ls, &ls);
	306	if (ret)
	307	goto out;
f46e9203	308
c3482b82	309	switch (value) {
f46e9203 NC	310	case LED_FULL:
	311	ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_LED_ON);
	312	break;
	313	case LED_OFF:
	314	ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_LED_OFF);
	315	break;
	316	case LED_HALF:
	317	ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_BLINK0);
	318	break;
	319	default:
	320	/*
	321	* Use PWM1 for all other values. This has the unwanted
	322	* side effect of making all LEDs on the chip share the
	323	* same brightness level if set to a value other than
	324	* OFF, HALF, or FULL. But, this is probably better than
	325	* just turning off for all other values.
	326	*/
1591caf2 CLG	327	ret = pca955x_write_pwm(pca955x->client, 1, 255 - value);
	328	if (ret)
	329	goto out;
f46e9203 NC	330	ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_BLINK1);
	331	break;
	332	}
	333
1591caf2	334	ret = pca955x_write_ls(pca955x->client, chip_ls, ls);
e7e11d8b	335
1591caf2	336	out:
e7e11d8b	337	mutex_unlock(&pca955x->lock);
f46e9203	338
1591caf2	339	return ret;
f46e9203 NC	340	}
f46e9203 NC	341
561099a1 CLG	342	#ifdef CONFIG_LEDS_PCA955X_GPIO
	343	/*
	344	* Read the INPUT register, which contains the state of LEDs.
	345	*/
1591caf2	346	static int pca955x_read_input(struct i2c_client client, int n, u8 val)
561099a1	347	{
1591caf2 CLG	348	int ret = i2c_smbus_read_byte_data(client, n);
	349
	350	if (ret < 0) {
	351	dev_err(&client->dev, "%s: reg 0x%x, err %d\n",
	352	__func__, n, ret);
	353	return ret;
	354	}
	355	*val = (u8)ret;
	356	return 0;
	357
561099a1 CLG	358	}
	359
	360	static int pca955x_gpio_request_pin(struct gpio_chip *gc, unsigned int offset)
	361	{
	362	struct pca955x *pca955x = gpiochip_get_data(gc);
	363	struct pca955x_led *led = &pca955x->leds[offset];
	364
	365	if (led->type == PCA955X_TYPE_GPIO)
	366	return 0;
	367
	368	return -EBUSY;
	369	}
	370
1591caf2 CLG	371	static int pca955x_set_value(struct gpio_chip *gc, unsigned int offset,
1591caf2 CLG	372	int val)
561099a1 CLG	373	{
	374	struct pca955x *pca955x = gpiochip_get_data(gc);
	375	struct pca955x_led *led = &pca955x->leds[offset];
	376
	377	if (val)
52ca7d0f AJ	378	return pca955x_led_set(&led->led_cdev, PCA955X_GPIO_HIGH);
	379
	380	return pca955x_led_set(&led->led_cdev, PCA955X_GPIO_LOW);
1591caf2 CLG	381	}
	382
	383	static void pca955x_gpio_set_value(struct gpio_chip *gc, unsigned int offset,
	384	int val)
	385	{
	386	pca955x_set_value(gc, offset, val);
561099a1 CLG	387	}
	388
	389	static int pca955x_gpio_get_value(struct gpio_chip *gc, unsigned int offset)
	390	{
	391	struct pca955x *pca955x = gpiochip_get_data(gc);
	392	struct pca955x_led *led = &pca955x->leds[offset];
1591caf2 CLG	393	u8 reg = 0;
	394
	395	/* There is nothing we can do about errors */
	396	pca955x_read_input(pca955x->client, led->led_num / 8, &reg);
561099a1 CLG	397
	398	return !!(reg & (1 << (led->led_num % 8)));
	399	}
	400
	401	static int pca955x_gpio_direction_input(struct gpio_chip *gc,
	402	unsigned int offset)
	403	{
52ca7d0f AJ	404	struct pca955x *pca955x = gpiochip_get_data(gc);
	405	struct pca955x_led *led = &pca955x->leds[offset];
	406
	407	/* To use as input ensure pin is not driven. */
	408	return pca955x_led_set(&led->led_cdev, PCA955X_GPIO_INPUT);
561099a1 CLG	409	}
	410
	411	static int pca955x_gpio_direction_output(struct gpio_chip *gc,
	412	unsigned int offset, int val)
	413	{
1591caf2	414	return pca955x_set_value(gc, offset, val);
561099a1 CLG	415	}
	416	#endif /* CONFIG_LEDS_PCA955X_GPIO */
	417
ed1f4b96	418	static struct pca955x_platform_data *
967f69de	419	pca955x_get_pdata(struct i2c_client client, struct pca955x_chipdef chip)
ed1f4b96	420	{
ed1f4b96	421	struct pca955x_platform_data *pdata;
2420ae02	422	struct pca955x_led *led;
967f69de	423	struct fwnode_handle *child;
ed1f4b96 CLG	424	int count;
ed1f4b96 CLG	425
967f69de	426	count = device_get_child_node_count(&client->dev);
ed1f4b96 CLG	427	if (!count \|\| count > chip->bits)
	428	return ERR_PTR(-ENODEV);
	429
	430	pdata = devm_kzalloc(&client->dev, sizeof(*pdata), GFP_KERNEL);
	431	if (!pdata)
	432	return ERR_PTR(-ENOMEM);
	433
a86854d0 KC	434	pdata->leds = devm_kcalloc(&client->dev,
a86854d0 KC	435	chip->bits, sizeof(struct pca955x_led),
ed1f4b96 CLG	436	GFP_KERNEL);
	437	if (!pdata->leds)
	438	return ERR_PTR(-ENOMEM);
	439
967f69de	440	device_for_each_child_node(&client->dev, child) {
ed1f4b96 CLG	441	const char *name;
	442	u32 reg;
	443	int res;
	444
967f69de	445	res = fwnode_property_read_u32(child, "reg", &reg);
ed1f4b96 CLG	446	if ((res != 0) \|\| (reg >= chip->bits))
	447	continue;
	448
967f69de AS	449	res = fwnode_property_read_string(child, "label", &name);
	450	if ((res != 0) && is_of_node(child))
	451	name = to_of_node(child)->name;
ed1f4b96	452
2420ae02 EJ	453	led = &pdata->leds[reg];
2420ae02 EJ	454	snprintf(led->name, sizeof(led->name), "%s", name);
ed1f4b96	455
2420ae02 EJ	456	led->type = PCA955X_TYPE_LED;
2420ae02 EJ	457	fwnode_property_read_u32(child, "type", &led->type);
967f69de	458	fwnode_property_read_string(child, "linux,default-trigger",
2420ae02	459	&led->default_trigger);
ed1f4b96 CLG	460	}
	461
	462	pdata->num_leds = chip->bits;
	463
	464	return pdata;
	465	}
	466
	467	static const struct of_device_id of_pca955x_match[] = {
	468	{ .compatible = "nxp,pca9550", .data = (void *)pca9550 },
	469	{ .compatible = "nxp,pca9551", .data = (void *)pca9551 },
	470	{ .compatible = "nxp,pca9552", .data = (void *)pca9552 },
46de3adb	471	{ .compatible = "ibm,pca9552", .data = (void *)ibm_pca9552 },
ed1f4b96 CLG	472	{ .compatible = "nxp,pca9553", .data = (void *)pca9553 },
	473	{},
	474	};
ed1f4b96	475	MODULE_DEVICE_TABLE(of, of_pca955x_match);
ed1f4b96	476
98ea1ea2	477	static int pca955x_probe(struct i2c_client *client,
2420ae02	478	const struct i2c_device_id *id)
f46e9203	479	{
e7e11d8b AS	480	struct pca955x *pca955x;
e7e11d8b AS	481	struct pca955x_led *pca955x_led;
f46e9203	482	struct pca955x_chipdef *chip;
2420ae02	483	struct led_classdev *led;
f46e9203	484	struct i2c_adapter *adapter;
95bf14bf	485	int i, err;
ed1f4b96	486	struct pca955x_platform_data *pdata;
561099a1	487	int ngpios = 0;
f46e9203	488
5b6cd445	489	chip = &pca955x_chipdefs[id->driver_data];
1c57d9bd	490	adapter = client->adapter;
87aae1ea	491	pdata = dev_get_platdata(&client->dev);
ed1f4b96	492	if (!pdata) {
967f69de	493	pdata = pca955x_get_pdata(client, chip);
ed1f4b96 CLG	494	if (IS_ERR(pdata))
	495	return PTR_ERR(pdata);
	496	}
f46e9203 NC	497
	498	/* Make sure the slave address / chip type combo given is possible */
	499	if ((client->addr & ~((1 << chip->slv_addr_shift) - 1)) !=
	500	chip->slv_addr) {
	501	dev_err(&client->dev, "invalid slave address %02x\n",
2420ae02	502	client->addr);
f46e9203 NC	503	return -ENODEV;
	504	}
	505
b40b0c17	506	dev_info(&client->dev, "leds-pca955x: Using %s %d-bit LED driver at "
2420ae02 EJ	507	"slave address 0x%02x\n", client->name, chip->bits,
2420ae02 EJ	508	client->addr);
f46e9203	509
aace34c0	510	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
f46e9203 NC	511	return -EIO;
f46e9203 NC	512
ed1f4b96 CLG	513	if (pdata->num_leds != chip->bits) {
	514	dev_err(&client->dev,
	515	"board info claims %d LEDs on a %d-bit chip\n",
	516	pdata->num_leds, chip->bits);
	517	return -ENODEV;
f46e9203 NC	518	}
f46e9203 NC	519
73759f6a	520	pca955x = devm_kzalloc(&client->dev, sizeof(*pca955x), GFP_KERNEL);
95bf14bf SW	521	if (!pca955x)
	522	return -ENOMEM;
	523
2420ae02 EJ	524	pca955x->leds = devm_kcalloc(&client->dev, chip->bits,
2420ae02 EJ	525	sizeof(*pca955x_led), GFP_KERNEL);
73759f6a BW	526	if (!pca955x->leds)
73759f6a BW	527	return -ENOMEM;
e7e11d8b	528
95bf14bf SW	529	i2c_set_clientdata(client, pca955x);
95bf14bf SW	530
e7e11d8b AS	531	mutex_init(&pca955x->lock);
	532	pca955x->client = client;
	533	pca955x->chipdef = chip;
	534
f46e9203	535	for (i = 0; i < chip->bits; i++) {
e7e11d8b AS	536	pca955x_led = &pca955x->leds[i];
	537	pca955x_led->led_num = i;
	538	pca955x_led->pca955x = pca955x;
561099a1 CLG	539	pca955x_led->type = pdata->leds[i].type;
	540
	541	switch (pca955x_led->type) {
	542	case PCA955X_TYPE_NONE:
	543	break;
	544	case PCA955X_TYPE_GPIO:
	545	ngpios++;
	546	break;
	547	case PCA955X_TYPE_LED:
	548	/*
	549	* Platform data can specify LED names and
	550	* default triggers
	551	*/
390c97dc JA	552	if (pdata->leds[i].name[0] == '\0')
390c97dc JA	553	snprintf(pdata->leds[i].name,
2420ae02	554	sizeof(pdata->leds[i].name), "%d", i);
390c97dc	555
2420ae02 EJ	556	snprintf(pca955x_led->name, sizeof(pca955x_led->name),
2420ae02 EJ	557	"pca955x:%s", pdata->leds[i].name);
390c97dc	558
2420ae02	559	led = &pca955x_led->led_cdev;
f46e9203	560	if (pdata->leds[i].default_trigger)
2420ae02	561	led->default_trigger =
f46e9203	562	pdata->leds[i].default_trigger;
f46e9203	563
2420ae02 EJ	564	led->name = pca955x_led->name;
2420ae02 EJ	565	led->brightness_set_blocking = pca955x_led_set;
7086625f	566	led->brightness_get = pca955x_led_get;
f46e9203	567
2420ae02	568	err = devm_led_classdev_register(&client->dev, led);
561099a1 CLG	569	if (err)
561099a1 CLG	570	return err;
f46e9203	571
561099a1	572	/* Turn off LED */
2420ae02	573	err = pca955x_led_set(led, LED_OFF);
1591caf2 CLG	574	if (err)
1591caf2 CLG	575	return err;
561099a1 CLG	576	}
561099a1 CLG	577	}
f46e9203 NC	578
f46e9203 NC	579	/* PWM0 is used for half brightness or 50% duty cycle */
1591caf2 CLG	580	err = pca955x_write_pwm(client, 0, 255 - LED_HALF);
	581	if (err)
	582	return err;
f46e9203 NC	583
f46e9203 NC	584	/* PWM1 is used for variable brightness, default to OFF */
1591caf2 CLG	585	err = pca955x_write_pwm(client, 1, 0);
	586	if (err)
	587	return err;
f46e9203 NC	588
f46e9203 NC	589	/* Set to fast frequency so we do not see flashing */
1591caf2 CLG	590	err = pca955x_write_psc(client, 0, 0);
	591	if (err)
	592	return err;
	593	err = pca955x_write_psc(client, 1, 0);
	594	if (err)
	595	return err;
f46e9203	596
561099a1 CLG	597	#ifdef CONFIG_LEDS_PCA955X_GPIO
	598	if (ngpios) {
	599	pca955x->gpio.label = "gpio-pca955x";
	600	pca955x->gpio.direction_input = pca955x_gpio_direction_input;
	601	pca955x->gpio.direction_output = pca955x_gpio_direction_output;
	602	pca955x->gpio.set = pca955x_gpio_set_value;
	603	pca955x->gpio.get = pca955x_gpio_get_value;
	604	pca955x->gpio.request = pca955x_gpio_request_pin;
	605	pca955x->gpio.can_sleep = 1;
	606	pca955x->gpio.base = -1;
	607	pca955x->gpio.ngpio = ngpios;
	608	pca955x->gpio.parent = &client->dev;
	609	pca955x->gpio.owner = THIS_MODULE;
	610
	611	err = devm_gpiochip_add_data(&client->dev, &pca955x->gpio,
	612	pca955x);
	613	if (err) {
	614	/* Use data->gpio.dev as a flag for freeing gpiochip */
	615	pca955x->gpio.parent = NULL;
	616	dev_warn(&client->dev, "could not add gpiochip\n");
	617	return err;
	618	}
	619	dev_info(&client->dev, "gpios %i...%i\n",
	620	pca955x->gpio.base, pca955x->gpio.base +
	621	pca955x->gpio.ngpio - 1);
	622	}
	623	#endif
	624
f46e9203	625	return 0;
f46e9203 NC	626	}
	627
	628	static struct i2c_driver pca955x_driver = {
	629	.driver = {
	630	.name = "leds-pca955x",
967f69de	631	.of_match_table = of_pca955x_match,
f46e9203 NC	632	},
f46e9203 NC	633	.probe = pca955x_probe,
f46e9203 NC	634	.id_table = pca955x_id,
	635	};
	636
09a0d183	637	module_i2c_driver(pca955x_driver);
f46e9203 NC	638
	639	MODULE_AUTHOR("Nate Case <ncase@xes-inc.com>");
	640	MODULE_DESCRIPTION("PCA955x LED driver");
	641	MODULE_LICENSE("GPL v2");