[linux-2.6-block.git] / drivers / leds / leds-pca955x.c

/*
 * Copyright 2007-2008 Extreme Engineering Solutions, Inc.
 *
 * Author: Nate Case <ncase@xes-inc.com>
 *
 * This file is subject to the terms and conditions of version 2 of
 * the GNU General Public License.  See the file COPYING in the main
 * directory of this archive for more details.
 *
 * 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/acpi.h>
#include <linux/ctype.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/gpio.h>
#include <linux/i2c.h>
#include <linux/leds.h>
#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/of.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,
	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,
	},
	[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 },
	{ "pca9553", pca9553 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, pca955x_id);

static const struct acpi_device_id pca955x_acpi_ids[] = {
	{ "PCA9550",  pca9550 },
	{ "PCA9551",  pca9551 },
	{ "PCA9552",  pca9552 },
	{ "PCA9553",  pca9553 },
	{ }
};
MODULE_DEVICE_TABLE(acpi, pca955x_acpi_ids);

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);
	int ret;

	ret = i2c_smbus_write_byte_data(client,
		pca95xx_num_input_regs(pca955x->chipdef->bits) + 2*n,
		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);
	int ret;

	ret = i2c_smbus_write_byte_data(client,
		pca95xx_num_input_regs(pca955x->chipdef->bits) + 1 + 2*n,
		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);
	int ret;

	ret = i2c_smbus_write_byte_data(client,
		pca95xx_num_input_regs(pca955x->chipdef->bits) + 4 + n,
		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);
	int ret;

	ret = i2c_smbus_read_byte_data(client,
		pca95xx_num_input_regs(pca955x->chipdef->bits) + 4 + 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_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 */

#if IS_ENABLED(CONFIG_OF)
static struct pca955x_platform_data *
pca955x_pdata_of_init(struct i2c_client *client, struct pca955x_chipdef *chip)
{
	struct device_node *np = client->dev.of_node;
	struct device_node *child;
	struct pca955x_platform_data *pdata;
	int count;

	count = of_get_child_count(np);
	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);

	for_each_child_of_node(np, child) {
		const char *name;
		u32 reg;
		int res;

		res = of_property_read_u32(child, "reg", &reg);
		if ((res != 0) || (reg >= chip->bits))
			continue;

		if (of_property_read_string(child, "label", &name))
			name = child->name;

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

		pdata->leds[reg].type = PCA955X_TYPE_LED;
		of_property_read_u32(child, "type", &pdata->leds[reg].type);
		of_property_read_string(child, "linux,default-trigger",
					&pdata->leds[reg].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 = "nxp,pca9553", .data = (void *)pca9553 },
	{},
};

MODULE_DEVICE_TABLE(of, of_pca955x_match);
#else
static struct pca955x_platform_data *
pca955x_pdata_of_init(struct i2c_client *client, struct pca955x_chipdef *chip)
{
	return ERR_PTR(-ENODEV);
}
#endif

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 i2c_adapter *adapter;
	int i, err;
	struct pca955x_platform_data *pdata;
	int ngpios = 0;

	if (id) {
		chip = &pca955x_chipdefs[id->driver_data];
	} else {
		const struct acpi_device_id *acpi_id;

		acpi_id = acpi_match_device(pca955x_acpi_ids, &client->dev);
		if (!acpi_id)
			return -ENODEV;
		chip = &pca955x_chipdefs[acpi_id->driver_data];
	}
	adapter = to_i2c_adapter(client->dev.parent);
	pdata = dev_get_platdata(&client->dev);
	if (!pdata) {
		pdata =	pca955x_pdata_of_init(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);

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

			pca955x_led->led_cdev.name = pca955x_led->name;
			pca955x_led->led_cdev.brightness_set_blocking =
				pca955x_led_set;

			err = devm_led_classdev_register(&client->dev,
							&pca955x_led->led_cdev);
			if (err)
				return err;

			/* Turn off LED */
			err = pca955x_led_set(&pca955x_led->led_cdev, 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",
		.acpi_match_table = ACPI_PTR(pca955x_acpi_ids),
		.of_match_table = of_match_ptr(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
f46e9203 NC	1	/*
	2	* Copyright 2007-2008 Extreme Engineering Solutions, Inc.
	3	*
	4	* Author: Nate Case <ncase@xes-inc.com>
	5	*
	6	* This file is subject to the terms and conditions of version 2 of
	7	* the GNU General Public License. See the file COPYING in the main
	8	* directory of this archive for more details.
	9	*
	10	* LED driver for various PCA955x I2C LED drivers
	11	*
	12	* Supported devices:
	13	*
	14	* Device Description 7-bit slave address
	15	* ------ ----------- -------------------
	16	* PCA9550 2-bit driver 0x60 .. 0x61
	17	* PCA9551 8-bit driver 0x60 .. 0x67
	18	* PCA9552 16-bit driver 0x60 .. 0x67
	19	* PCA9553/01 4-bit driver 0x62
	20	* PCA9553/02 4-bit driver 0x63
	21	*
	22	* Philips PCA955x LED driver chips follow a register map as shown below:
	23	*
	24	* Control Register Description
	25	* ---------------- -----------
	26	* 0x0 Input register 0
	27	* ..
	28	* NUM_INPUT_REGS - 1 Last Input register X
	29	*
	30	* NUM_INPUT_REGS Frequency prescaler 0
	31	* NUM_INPUT_REGS + 1 PWM register 0
	32	* NUM_INPUT_REGS + 2 Frequency prescaler 1
	33	* NUM_INPUT_REGS + 3 PWM register 1
	34	*
	35	* NUM_INPUT_REGS + 4 LED selector 0
	36	* NUM_INPUT_REGS + 4
	37	* + NUM_LED_REGS - 1 Last LED selector
	38	*
	39	* where NUM_INPUT_REGS and NUM_LED_REGS vary depending on how many
	40	* bits the chip supports.
	41	*/
	42
44b3e31d	43	#include <linux/acpi.h>
f46e9203	44	#include <linux/ctype.h>
ed1f4b96	45	#include <linux/delay.h>
f46e9203	46	#include <linux/err.h>
ed1f4b96	47	#include <linux/gpio.h>
f46e9203	48	#include <linux/i2c.h>
ed1f4b96 CLG	49	#include <linux/leds.h>
	50	#include <linux/module.h>
	51	#include <linux/of_device.h>
	52	#include <linux/of.h>
5a0e3ad6	53	#include <linux/slab.h>
ed1f4b96	54	#include <linux/string.h>
f46e9203	55
561099a1 CLG	56	#include <dt-bindings/leds/leds-pca955x.h>
561099a1 CLG	57
f46e9203 NC	58	/* LED select registers determine the source that drives LED outputs */
	59	#define PCA955X_LS_LED_ON 0x0 /* Output LOW */
	60	#define PCA955X_LS_LED_OFF 0x1 /* Output HI-Z */
	61	#define PCA955X_LS_BLINK0 0x2 /* Blink at PWM0 rate */
	62	#define PCA955X_LS_BLINK1 0x3 /* Blink at PWM1 rate */
	63
52ca7d0f AJ	64	#define PCA955X_GPIO_INPUT LED_OFF
	65	#define PCA955X_GPIO_HIGH LED_OFF
	66	#define PCA955X_GPIO_LOW LED_FULL
	67
f46e9203 NC	68	enum pca955x_type {
	69	pca9550,
	70	pca9551,
	71	pca9552,
	72	pca9553,
	73	};
	74
	75	struct pca955x_chipdef {
	76	int bits;
	77	u8 slv_addr; /* 7-bit slave address mask */
	78	int slv_addr_shift; /* Number of bits to ignore */
	79	};
	80
	81	static struct pca955x_chipdef pca955x_chipdefs[] = {
	82	[pca9550] = {
	83	.bits = 2,
	84	.slv_addr = /* 110000x */ 0x60,
	85	.slv_addr_shift = 1,
	86	},
	87	[pca9551] = {
	88	.bits = 8,
	89	.slv_addr = /* 1100xxx */ 0x60,
	90	.slv_addr_shift = 3,
	91	},
	92	[pca9552] = {
	93	.bits = 16,
	94	.slv_addr = /* 1100xxx */ 0x60,
	95	.slv_addr_shift = 3,
	96	},
	97	[pca9553] = {
	98	.bits = 4,
	99	.slv_addr = /* 110001x */ 0x62,
	100	.slv_addr_shift = 1,
	101	},
	102	};
	103
	104	static const struct i2c_device_id pca955x_id[] = {
	105	{ "pca9550", pca9550 },
	106	{ "pca9551", pca9551 },
	107	{ "pca9552", pca9552 },
	108	{ "pca9553", pca9553 },
	109	{ }
	110	};
	111	MODULE_DEVICE_TABLE(i2c, pca955x_id);
	112
44b3e31d TH	113	static const struct acpi_device_id pca955x_acpi_ids[] = {
	114	{ "PCA9550", pca9550 },
	115	{ "PCA9551", pca9551 },
	116	{ "PCA9552", pca9552 },
	117	{ "PCA9553", pca9553 },
	118	{ }
	119	};
	120	MODULE_DEVICE_TABLE(acpi, pca955x_acpi_ids);
	121
e7e11d8b AS	122	struct pca955x {
	123	struct mutex lock;
	124	struct pca955x_led *leds;
f46e9203 NC	125	struct pca955x_chipdef *chipdef;
f46e9203 NC	126	struct i2c_client *client;
561099a1 CLG	127	#ifdef CONFIG_LEDS_PCA955X_GPIO
	128	struct gpio_chip gpio;
	129	#endif
e7e11d8b AS	130	};
	131
	132	struct pca955x_led {
	133	struct pca955x *pca955x;
f46e9203 NC	134	struct led_classdev led_cdev;
	135	int led_num; /* 0 .. 15 potentially */
	136	char name[32];
561099a1	137	u32 type;
ed1f4b96 CLG	138	const char *default_trigger;
	139	};
	140
	141	struct pca955x_platform_data {
	142	struct pca955x_led *leds;
	143	int num_leds;
f46e9203 NC	144	};
	145
	146	/* 8 bits per input register */
	147	static inline int pca95xx_num_input_regs(int bits)
	148	{
	149	return (bits + 7) / 8;
	150	}
	151
	152	/* 4 bits per LED selector register */
	153	static inline int pca95xx_num_led_regs(int bits)
	154	{
	155	return (bits + 3) / 4;
	156	}
	157
	158	/*
	159	* Return an LED selector register value based on an existing one, with
	160	* the appropriate 2-bit state value set for the given LED number (0-3).
	161	*/
	162	static inline u8 pca955x_ledsel(u8 oldval, int led_num, int state)
	163	{
	164	return (oldval & (~(0x3 << (led_num << 1)))) \|
	165	((state & 0x3) << (led_num << 1));
	166	}
	167
	168	/*
	169	* Write to frequency prescaler register, used to program the
	170	* period of the PWM output. period = (PSCx + 1) / 38
	171	*/
1591caf2	172	static int pca955x_write_psc(struct i2c_client *client, int n, u8 val)
f46e9203	173	{
e7e11d8b	174	struct pca955x *pca955x = i2c_get_clientdata(client);
1591caf2	175	int ret;
f46e9203	176
1591caf2	177	ret = i2c_smbus_write_byte_data(client,
f46e9203 NC	178	pca95xx_num_input_regs(pca955x->chipdef->bits) + 2*n,
f46e9203 NC	179	val);
1591caf2 CLG	180	if (ret < 0)
	181	dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n",
	182	__func__, n, val, ret);
	183	return ret;
f46e9203 NC	184	}
	185
	186	/*
	187	* Write to PWM register, which determines the duty cycle of the
	188	* output. LED is OFF when the count is less than the value of this
	189	* register, and ON when it is greater. If PWMx == 0, LED is always OFF.
	190	*
	191	* Duty cycle is (256 - PWMx) / 256
	192	*/
1591caf2	193	static int pca955x_write_pwm(struct i2c_client *client, int n, u8 val)
f46e9203	194	{
e7e11d8b	195	struct pca955x *pca955x = i2c_get_clientdata(client);
1591caf2	196	int ret;
f46e9203	197
1591caf2	198	ret = i2c_smbus_write_byte_data(client,
f46e9203 NC	199	pca95xx_num_input_regs(pca955x->chipdef->bits) + 1 + 2*n,
f46e9203 NC	200	val);
1591caf2 CLG	201	if (ret < 0)
	202	dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n",
	203	__func__, n, val, ret);
	204	return ret;
f46e9203 NC	205	}
	206
	207	/*
	208	* Write to LED selector register, which determines the source that
	209	* drives the LED output.
	210	*/
1591caf2	211	static int pca955x_write_ls(struct i2c_client *client, int n, u8 val)
f46e9203	212	{
e7e11d8b	213	struct pca955x *pca955x = i2c_get_clientdata(client);
1591caf2	214	int ret;
f46e9203	215
1591caf2	216	ret = i2c_smbus_write_byte_data(client,
f46e9203 NC	217	pca95xx_num_input_regs(pca955x->chipdef->bits) + 4 + n,
f46e9203 NC	218	val);
1591caf2 CLG	219	if (ret < 0)
	220	dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n",
	221	__func__, n, val, ret);
	222	return ret;
f46e9203 NC	223	}
	224
	225	/*
	226	* Read the LED selector register, which determines the source that
	227	* drives the LED output.
	228	*/
1591caf2	229	static int pca955x_read_ls(struct i2c_client client, int n, u8 val)
f46e9203	230	{
e7e11d8b	231	struct pca955x *pca955x = i2c_get_clientdata(client);
1591caf2	232	int ret;
f46e9203	233
1591caf2	234	ret = i2c_smbus_read_byte_data(client,
f46e9203	235	pca95xx_num_input_regs(pca955x->chipdef->bits) + 4 + n);
1591caf2 CLG	236	if (ret < 0) {
	237	dev_err(&client->dev, "%s: reg 0x%x, err %d\n",
	238	__func__, n, ret);
	239	return ret;
	240	}
	241	*val = (u8)ret;
	242	return 0;
f46e9203 NC	243	}
f46e9203 NC	244
c3482b82 AL	245	static int pca955x_led_set(struct led_classdev *led_cdev,
c3482b82 AL	246	enum led_brightness value)
f46e9203	247	{
e7e11d8b AS	248	struct pca955x_led *pca955x_led;
e7e11d8b AS	249	struct pca955x *pca955x;
f46e9203 NC	250	u8 ls;
	251	int chip_ls; /* which LSx to use (0-3 potentially) */
	252	int ls_led; /* which set of bits within LSx to use (0-3) */
1591caf2	253	int ret;
f46e9203	254
c3482b82	255	pca955x_led = container_of(led_cdev, struct pca955x_led, led_cdev);
e7e11d8b AS	256	pca955x = pca955x_led->pca955x;
	257
	258	chip_ls = pca955x_led->led_num / 4;
	259	ls_led = pca955x_led->led_num % 4;
	260
	261	mutex_lock(&pca955x->lock);
f46e9203	262
1591caf2 CLG	263	ret = pca955x_read_ls(pca955x->client, chip_ls, &ls);
	264	if (ret)
	265	goto out;
f46e9203	266
c3482b82	267	switch (value) {
f46e9203 NC	268	case LED_FULL:
	269	ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_LED_ON);
	270	break;
	271	case LED_OFF:
	272	ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_LED_OFF);
	273	break;
	274	case LED_HALF:
	275	ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_BLINK0);
	276	break;
	277	default:
	278	/*
	279	* Use PWM1 for all other values. This has the unwanted
	280	* side effect of making all LEDs on the chip share the
	281	* same brightness level if set to a value other than
	282	* OFF, HALF, or FULL. But, this is probably better than
	283	* just turning off for all other values.
	284	*/
1591caf2 CLG	285	ret = pca955x_write_pwm(pca955x->client, 1, 255 - value);
	286	if (ret)
	287	goto out;
f46e9203 NC	288	ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_BLINK1);
	289	break;
	290	}
	291
1591caf2	292	ret = pca955x_write_ls(pca955x->client, chip_ls, ls);
e7e11d8b	293
1591caf2	294	out:
e7e11d8b	295	mutex_unlock(&pca955x->lock);
f46e9203	296
1591caf2	297	return ret;
f46e9203 NC	298	}
f46e9203 NC	299
561099a1 CLG	300	#ifdef CONFIG_LEDS_PCA955X_GPIO
	301	/*
	302	* Read the INPUT register, which contains the state of LEDs.
	303	*/
1591caf2	304	static int pca955x_read_input(struct i2c_client client, int n, u8 val)
561099a1	305	{
1591caf2 CLG	306	int ret = i2c_smbus_read_byte_data(client, n);
	307
	308	if (ret < 0) {
	309	dev_err(&client->dev, "%s: reg 0x%x, err %d\n",
	310	__func__, n, ret);
	311	return ret;
	312	}
	313	*val = (u8)ret;
	314	return 0;
	315
561099a1 CLG	316	}
	317
	318	static int pca955x_gpio_request_pin(struct gpio_chip *gc, unsigned int offset)
	319	{
	320	struct pca955x *pca955x = gpiochip_get_data(gc);
	321	struct pca955x_led *led = &pca955x->leds[offset];
	322
	323	if (led->type == PCA955X_TYPE_GPIO)
	324	return 0;
	325
	326	return -EBUSY;
	327	}
	328
1591caf2 CLG	329	static int pca955x_set_value(struct gpio_chip *gc, unsigned int offset,
1591caf2 CLG	330	int val)
561099a1 CLG	331	{
	332	struct pca955x *pca955x = gpiochip_get_data(gc);
	333	struct pca955x_led *led = &pca955x->leds[offset];
	334
	335	if (val)
52ca7d0f AJ	336	return pca955x_led_set(&led->led_cdev, PCA955X_GPIO_HIGH);
	337
	338	return pca955x_led_set(&led->led_cdev, PCA955X_GPIO_LOW);
1591caf2 CLG	339	}
	340
	341	static void pca955x_gpio_set_value(struct gpio_chip *gc, unsigned int offset,
	342	int val)
	343	{
	344	pca955x_set_value(gc, offset, val);
561099a1 CLG	345	}
	346
	347	static int pca955x_gpio_get_value(struct gpio_chip *gc, unsigned int offset)
	348	{
	349	struct pca955x *pca955x = gpiochip_get_data(gc);
	350	struct pca955x_led *led = &pca955x->leds[offset];
1591caf2 CLG	351	u8 reg = 0;
	352
	353	/* There is nothing we can do about errors */
	354	pca955x_read_input(pca955x->client, led->led_num / 8, &reg);
561099a1 CLG	355
	356	return !!(reg & (1 << (led->led_num % 8)));
	357	}
	358
	359	static int pca955x_gpio_direction_input(struct gpio_chip *gc,
	360	unsigned int offset)
	361	{
52ca7d0f AJ	362	struct pca955x *pca955x = gpiochip_get_data(gc);
	363	struct pca955x_led *led = &pca955x->leds[offset];
	364
	365	/* To use as input ensure pin is not driven. */
	366	return pca955x_led_set(&led->led_cdev, PCA955X_GPIO_INPUT);
561099a1 CLG	367	}
	368
	369	static int pca955x_gpio_direction_output(struct gpio_chip *gc,
	370	unsigned int offset, int val)
	371	{
1591caf2	372	return pca955x_set_value(gc, offset, val);
561099a1 CLG	373	}
	374	#endif /* CONFIG_LEDS_PCA955X_GPIO */
	375
ed1f4b96 CLG	376	#if IS_ENABLED(CONFIG_OF)
	377	static struct pca955x_platform_data *
	378	pca955x_pdata_of_init(struct i2c_client client, struct pca955x_chipdef chip)
	379	{
	380	struct device_node *np = client->dev.of_node;
	381	struct device_node *child;
	382	struct pca955x_platform_data *pdata;
	383	int count;
	384
	385	count = of_get_child_count(np);
	386	if (!count \|\| count > chip->bits)
	387	return ERR_PTR(-ENODEV);
	388
	389	pdata = devm_kzalloc(&client->dev, sizeof(*pdata), GFP_KERNEL);
	390	if (!pdata)
	391	return ERR_PTR(-ENOMEM);
	392
a86854d0 KC	393	pdata->leds = devm_kcalloc(&client->dev,
a86854d0 KC	394	chip->bits, sizeof(struct pca955x_led),
ed1f4b96 CLG	395	GFP_KERNEL);
	396	if (!pdata->leds)
	397	return ERR_PTR(-ENOMEM);
	398
	399	for_each_child_of_node(np, child) {
	400	const char *name;
	401	u32 reg;
	402	int res;
	403
	404	res = of_property_read_u32(child, "reg", &reg);
	405	if ((res != 0) \|\| (reg >= chip->bits))
	406	continue;
	407
	408	if (of_property_read_string(child, "label", &name))
	409	name = child->name;
	410
	411	snprintf(pdata->leds[reg].name, sizeof(pdata->leds[reg].name),
	412	"%s", name);
	413
561099a1 CLG	414	pdata->leds[reg].type = PCA955X_TYPE_LED;
561099a1 CLG	415	of_property_read_u32(child, "type", &pdata->leds[reg].type);
ed1f4b96 CLG	416	of_property_read_string(child, "linux,default-trigger",
	417	&pdata->leds[reg].default_trigger);
	418	}
	419
	420	pdata->num_leds = chip->bits;
	421
	422	return pdata;
	423	}
	424
	425	static const struct of_device_id of_pca955x_match[] = {
	426	{ .compatible = "nxp,pca9550", .data = (void *)pca9550 },
	427	{ .compatible = "nxp,pca9551", .data = (void *)pca9551 },
	428	{ .compatible = "nxp,pca9552", .data = (void *)pca9552 },
	429	{ .compatible = "nxp,pca9553", .data = (void *)pca9553 },
	430	{},
	431	};
	432
	433	MODULE_DEVICE_TABLE(of, of_pca955x_match);
	434	#else
	435	static struct pca955x_platform_data *
	436	pca955x_pdata_of_init(struct i2c_client client, struct pca955x_chipdef chip)
	437	{
	438	return ERR_PTR(-ENODEV);
	439	}
	440	#endif
	441
98ea1ea2	442	static int pca955x_probe(struct i2c_client *client,
f46e9203 NC	443	const struct i2c_device_id *id)
f46e9203 NC	444	{
e7e11d8b AS	445	struct pca955x *pca955x;
e7e11d8b AS	446	struct pca955x_led *pca955x_led;
f46e9203 NC	447	struct pca955x_chipdef *chip;
f46e9203 NC	448	struct i2c_adapter *adapter;
95bf14bf	449	int i, err;
ed1f4b96	450	struct pca955x_platform_data *pdata;
561099a1	451	int ngpios = 0;
f46e9203	452
44b3e31d TH	453	if (id) {
	454	chip = &pca955x_chipdefs[id->driver_data];
	455	} else {
	456	const struct acpi_device_id *acpi_id;
	457
	458	acpi_id = acpi_match_device(pca955x_acpi_ids, &client->dev);
	459	if (!acpi_id)
	460	return -ENODEV;
	461	chip = &pca955x_chipdefs[acpi_id->driver_data];
	462	}
f46e9203	463	adapter = to_i2c_adapter(client->dev.parent);
87aae1ea	464	pdata = dev_get_platdata(&client->dev);
ed1f4b96 CLG	465	if (!pdata) {
	466	pdata = pca955x_pdata_of_init(client, chip);
	467	if (IS_ERR(pdata))
	468	return PTR_ERR(pdata);
	469	}
f46e9203 NC	470
	471	/* Make sure the slave address / chip type combo given is possible */
	472	if ((client->addr & ~((1 << chip->slv_addr_shift) - 1)) !=
	473	chip->slv_addr) {
	474	dev_err(&client->dev, "invalid slave address %02x\n",
	475	client->addr);
	476	return -ENODEV;
	477	}
	478
b40b0c17	479	dev_info(&client->dev, "leds-pca955x: Using %s %d-bit LED driver at "
f46e9203	480	"slave address 0x%02x\n",
44b3e31d	481	client->name, chip->bits, client->addr);
f46e9203	482
aace34c0	483	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
f46e9203 NC	484	return -EIO;
f46e9203 NC	485
ed1f4b96 CLG	486	if (pdata->num_leds != chip->bits) {
	487	dev_err(&client->dev,
	488	"board info claims %d LEDs on a %d-bit chip\n",
	489	pdata->num_leds, chip->bits);
	490	return -ENODEV;
f46e9203 NC	491	}
f46e9203 NC	492
73759f6a	493	pca955x = devm_kzalloc(&client->dev, sizeof(*pca955x), GFP_KERNEL);
95bf14bf SW	494	if (!pca955x)
	495	return -ENOMEM;
	496
a86854d0 KC	497	pca955x->leds = devm_kcalloc(&client->dev,
a86854d0 KC	498	chip->bits, sizeof(*pca955x_led), GFP_KERNEL);
73759f6a BW	499	if (!pca955x->leds)
73759f6a BW	500	return -ENOMEM;
e7e11d8b	501
95bf14bf SW	502	i2c_set_clientdata(client, pca955x);
95bf14bf SW	503
e7e11d8b AS	504	mutex_init(&pca955x->lock);
	505	pca955x->client = client;
	506	pca955x->chipdef = chip;
	507
f46e9203	508	for (i = 0; i < chip->bits; i++) {
e7e11d8b AS	509	pca955x_led = &pca955x->leds[i];
	510	pca955x_led->led_num = i;
	511	pca955x_led->pca955x = pca955x;
561099a1 CLG	512	pca955x_led->type = pdata->leds[i].type;
	513
	514	switch (pca955x_led->type) {
	515	case PCA955X_TYPE_NONE:
	516	break;
	517	case PCA955X_TYPE_GPIO:
	518	ngpios++;
	519	break;
	520	case PCA955X_TYPE_LED:
	521	/*
	522	* Platform data can specify LED names and
	523	* default triggers
	524	*/
390c97dc JA	525	if (pdata->leds[i].name[0] == '\0')
	526	snprintf(pdata->leds[i].name,
	527	sizeof(pdata->leds[i].name), "%d", i);
	528
	529	snprintf(pca955x_led->name,
	530	sizeof(pca955x_led->name), "pca955x:%s",
	531	pdata->leds[i].name);
	532
f46e9203	533	if (pdata->leds[i].default_trigger)
e7e11d8b	534	pca955x_led->led_cdev.default_trigger =
f46e9203	535	pdata->leds[i].default_trigger;
f46e9203	536
561099a1 CLG	537	pca955x_led->led_cdev.name = pca955x_led->name;
	538	pca955x_led->led_cdev.brightness_set_blocking =
	539	pca955x_led_set;
f46e9203	540
561099a1 CLG	541	err = devm_led_classdev_register(&client->dev,
	542	&pca955x_led->led_cdev);
	543	if (err)
	544	return err;
f46e9203	545
561099a1	546	/* Turn off LED */
1591caf2 CLG	547	err = pca955x_led_set(&pca955x_led->led_cdev, LED_OFF);
	548	if (err)
	549	return err;
561099a1 CLG	550	}
561099a1 CLG	551	}
f46e9203 NC	552
f46e9203 NC	553	/* PWM0 is used for half brightness or 50% duty cycle */
1591caf2 CLG	554	err = pca955x_write_pwm(client, 0, 255 - LED_HALF);
	555	if (err)
	556	return err;
f46e9203 NC	557
f46e9203 NC	558	/* PWM1 is used for variable brightness, default to OFF */
1591caf2 CLG	559	err = pca955x_write_pwm(client, 1, 0);
	560	if (err)
	561	return err;
f46e9203 NC	562
f46e9203 NC	563	/* Set to fast frequency so we do not see flashing */
1591caf2 CLG	564	err = pca955x_write_psc(client, 0, 0);
	565	if (err)
	566	return err;
	567	err = pca955x_write_psc(client, 1, 0);
	568	if (err)
	569	return err;
f46e9203	570
561099a1 CLG	571	#ifdef CONFIG_LEDS_PCA955X_GPIO
	572	if (ngpios) {
	573	pca955x->gpio.label = "gpio-pca955x";
	574	pca955x->gpio.direction_input = pca955x_gpio_direction_input;
	575	pca955x->gpio.direction_output = pca955x_gpio_direction_output;
	576	pca955x->gpio.set = pca955x_gpio_set_value;
	577	pca955x->gpio.get = pca955x_gpio_get_value;
	578	pca955x->gpio.request = pca955x_gpio_request_pin;
	579	pca955x->gpio.can_sleep = 1;
	580	pca955x->gpio.base = -1;
	581	pca955x->gpio.ngpio = ngpios;
	582	pca955x->gpio.parent = &client->dev;
	583	pca955x->gpio.owner = THIS_MODULE;
	584
	585	err = devm_gpiochip_add_data(&client->dev, &pca955x->gpio,
	586	pca955x);
	587	if (err) {
	588	/* Use data->gpio.dev as a flag for freeing gpiochip */
	589	pca955x->gpio.parent = NULL;
	590	dev_warn(&client->dev, "could not add gpiochip\n");
	591	return err;
	592	}
	593	dev_info(&client->dev, "gpios %i...%i\n",
	594	pca955x->gpio.base, pca955x->gpio.base +
	595	pca955x->gpio.ngpio - 1);
	596	}
	597	#endif
	598
f46e9203	599	return 0;
f46e9203 NC	600	}
	601
	602	static struct i2c_driver pca955x_driver = {
	603	.driver = {
	604	.name = "leds-pca955x",
44b3e31d	605	.acpi_match_table = ACPI_PTR(pca955x_acpi_ids),
ed1f4b96	606	.of_match_table = of_match_ptr(of_pca955x_match),
f46e9203 NC	607	},
f46e9203 NC	608	.probe = pca955x_probe,
f46e9203 NC	609	.id_table = pca955x_id,
	610	};
	611
09a0d183	612	module_i2c_driver(pca955x_driver);
f46e9203 NC	613
	614	MODULE_AUTHOR("Nate Case <ncase@xes-inc.com>");
	615	MODULE_DESCRIPTION("PCA955x LED driver");
	616	MODULE_LICENSE("GPL v2");