[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);
	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 */

static struct pca955x_platform_data *
pca955x_get_pdata(struct i2c_client *client, struct pca955x_chipdef *chip)
{
	struct pca955x_platform_data *pdata;
	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;

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

		pdata->leds[reg].type = PCA955X_TYPE_LED;
		fwnode_property_read_u32(child, "type", &pdata->leds[reg].type);
		fwnode_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 = "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 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);

			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",
		.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);
1591caf2	169	int ret;
f46e9203	170
1591caf2	171	ret = i2c_smbus_write_byte_data(client,
f46e9203 NC	172	pca95xx_num_input_regs(pca955x->chipdef->bits) + 2*n,
f46e9203 NC	173	val);
1591caf2 CLG	174	if (ret < 0)
	175	dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n",
	176	__func__, n, val, ret);
	177	return ret;
f46e9203 NC	178	}
	179
	180	/*
	181	* Write to PWM register, which determines the duty cycle of the
	182	* output. LED is OFF when the count is less than the value of this
	183	* register, and ON when it is greater. If PWMx == 0, LED is always OFF.
	184	*
	185	* Duty cycle is (256 - PWMx) / 256
	186	*/
1591caf2	187	static int pca955x_write_pwm(struct i2c_client *client, int n, u8 val)
f46e9203	188	{
e7e11d8b	189	struct pca955x *pca955x = i2c_get_clientdata(client);
1591caf2	190	int ret;
f46e9203	191
1591caf2	192	ret = i2c_smbus_write_byte_data(client,
f46e9203 NC	193	pca95xx_num_input_regs(pca955x->chipdef->bits) + 1 + 2*n,
f46e9203 NC	194	val);
1591caf2 CLG	195	if (ret < 0)
	196	dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n",
	197	__func__, n, val, ret);
	198	return ret;
f46e9203 NC	199	}
	200
	201	/*
	202	* Write to LED selector register, which determines the source that
	203	* drives the LED output.
	204	*/
1591caf2	205	static int pca955x_write_ls(struct i2c_client *client, int n, u8 val)
f46e9203	206	{
e7e11d8b	207	struct pca955x *pca955x = i2c_get_clientdata(client);
1591caf2	208	int ret;
f46e9203	209
1591caf2	210	ret = i2c_smbus_write_byte_data(client,
f46e9203 NC	211	pca95xx_num_input_regs(pca955x->chipdef->bits) + 4 + n,
f46e9203 NC	212	val);
1591caf2 CLG	213	if (ret < 0)
	214	dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n",
	215	__func__, n, val, ret);
	216	return ret;
f46e9203 NC	217	}
	218
	219	/*
	220	* Read the LED selector register, which determines the source that
	221	* drives the LED output.
	222	*/
1591caf2	223	static int pca955x_read_ls(struct i2c_client client, int n, u8 val)
f46e9203	224	{
e7e11d8b	225	struct pca955x *pca955x = i2c_get_clientdata(client);
1591caf2	226	int ret;
f46e9203	227
1591caf2	228	ret = i2c_smbus_read_byte_data(client,
f46e9203	229	pca95xx_num_input_regs(pca955x->chipdef->bits) + 4 + n);
1591caf2 CLG	230	if (ret < 0) {
	231	dev_err(&client->dev, "%s: reg 0x%x, err %d\n",
	232	__func__, n, ret);
	233	return ret;
	234	}
	235	*val = (u8)ret;
	236	return 0;
f46e9203 NC	237	}
f46e9203 NC	238
c3482b82 AL	239	static int pca955x_led_set(struct led_classdev *led_cdev,
c3482b82 AL	240	enum led_brightness value)
f46e9203	241	{
e7e11d8b AS	242	struct pca955x_led *pca955x_led;
e7e11d8b AS	243	struct pca955x *pca955x;
f46e9203 NC	244	u8 ls;
	245	int chip_ls; /* which LSx to use (0-3 potentially) */
	246	int ls_led; /* which set of bits within LSx to use (0-3) */
1591caf2	247	int ret;
f46e9203	248
c3482b82	249	pca955x_led = container_of(led_cdev, struct pca955x_led, led_cdev);
e7e11d8b AS	250	pca955x = pca955x_led->pca955x;
	251
	252	chip_ls = pca955x_led->led_num / 4;
	253	ls_led = pca955x_led->led_num % 4;
	254
	255	mutex_lock(&pca955x->lock);
f46e9203	256
1591caf2 CLG	257	ret = pca955x_read_ls(pca955x->client, chip_ls, &ls);
	258	if (ret)
	259	goto out;
f46e9203	260
c3482b82	261	switch (value) {
f46e9203 NC	262	case LED_FULL:
	263	ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_LED_ON);
	264	break;
	265	case LED_OFF:
	266	ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_LED_OFF);
	267	break;
	268	case LED_HALF:
	269	ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_BLINK0);
	270	break;
	271	default:
	272	/*
	273	* Use PWM1 for all other values. This has the unwanted
	274	* side effect of making all LEDs on the chip share the
	275	* same brightness level if set to a value other than
	276	* OFF, HALF, or FULL. But, this is probably better than
	277	* just turning off for all other values.
	278	*/
1591caf2 CLG	279	ret = pca955x_write_pwm(pca955x->client, 1, 255 - value);
	280	if (ret)
	281	goto out;
f46e9203 NC	282	ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_BLINK1);
	283	break;
	284	}
	285
1591caf2	286	ret = pca955x_write_ls(pca955x->client, chip_ls, ls);
e7e11d8b	287
1591caf2	288	out:
e7e11d8b	289	mutex_unlock(&pca955x->lock);
f46e9203	290
1591caf2	291	return ret;
f46e9203 NC	292	}
f46e9203 NC	293
561099a1 CLG	294	#ifdef CONFIG_LEDS_PCA955X_GPIO
	295	/*
	296	* Read the INPUT register, which contains the state of LEDs.
	297	*/
1591caf2	298	static int pca955x_read_input(struct i2c_client client, int n, u8 val)
561099a1	299	{
1591caf2 CLG	300	int ret = i2c_smbus_read_byte_data(client, n);
	301
	302	if (ret < 0) {
	303	dev_err(&client->dev, "%s: reg 0x%x, err %d\n",
	304	__func__, n, ret);
	305	return ret;
	306	}
	307	*val = (u8)ret;
	308	return 0;
	309
561099a1 CLG	310	}
	311
	312	static int pca955x_gpio_request_pin(struct gpio_chip *gc, unsigned int offset)
	313	{
	314	struct pca955x *pca955x = gpiochip_get_data(gc);
	315	struct pca955x_led *led = &pca955x->leds[offset];
	316
	317	if (led->type == PCA955X_TYPE_GPIO)
	318	return 0;
	319
	320	return -EBUSY;
	321	}
	322
1591caf2 CLG	323	static int pca955x_set_value(struct gpio_chip *gc, unsigned int offset,
1591caf2 CLG	324	int val)
561099a1 CLG	325	{
	326	struct pca955x *pca955x = gpiochip_get_data(gc);
	327	struct pca955x_led *led = &pca955x->leds[offset];
	328
	329	if (val)
52ca7d0f AJ	330	return pca955x_led_set(&led->led_cdev, PCA955X_GPIO_HIGH);
	331
	332	return pca955x_led_set(&led->led_cdev, PCA955X_GPIO_LOW);
1591caf2 CLG	333	}
	334
	335	static void pca955x_gpio_set_value(struct gpio_chip *gc, unsigned int offset,
	336	int val)
	337	{
	338	pca955x_set_value(gc, offset, val);
561099a1 CLG	339	}
	340
	341	static int pca955x_gpio_get_value(struct gpio_chip *gc, unsigned int offset)
	342	{
	343	struct pca955x *pca955x = gpiochip_get_data(gc);
	344	struct pca955x_led *led = &pca955x->leds[offset];
1591caf2 CLG	345	u8 reg = 0;
	346
	347	/* There is nothing we can do about errors */
	348	pca955x_read_input(pca955x->client, led->led_num / 8, &reg);
561099a1 CLG	349
	350	return !!(reg & (1 << (led->led_num % 8)));
	351	}
	352
	353	static int pca955x_gpio_direction_input(struct gpio_chip *gc,
	354	unsigned int offset)
	355	{
52ca7d0f AJ	356	struct pca955x *pca955x = gpiochip_get_data(gc);
	357	struct pca955x_led *led = &pca955x->leds[offset];
	358
	359	/* To use as input ensure pin is not driven. */
	360	return pca955x_led_set(&led->led_cdev, PCA955X_GPIO_INPUT);
561099a1 CLG	361	}
	362
	363	static int pca955x_gpio_direction_output(struct gpio_chip *gc,
	364	unsigned int offset, int val)
	365	{
1591caf2	366	return pca955x_set_value(gc, offset, val);
561099a1 CLG	367	}
	368	#endif /* CONFIG_LEDS_PCA955X_GPIO */
	369
ed1f4b96	370	static struct pca955x_platform_data *
967f69de	371	pca955x_get_pdata(struct i2c_client client, struct pca955x_chipdef chip)
ed1f4b96	372	{
ed1f4b96	373	struct pca955x_platform_data *pdata;
967f69de	374	struct fwnode_handle *child;
ed1f4b96 CLG	375	int count;
ed1f4b96 CLG	376
967f69de	377	count = device_get_child_node_count(&client->dev);
ed1f4b96 CLG	378	if (!count \|\| count > chip->bits)
	379	return ERR_PTR(-ENODEV);
	380
	381	pdata = devm_kzalloc(&client->dev, sizeof(*pdata), GFP_KERNEL);
	382	if (!pdata)
	383	return ERR_PTR(-ENOMEM);
	384
a86854d0 KC	385	pdata->leds = devm_kcalloc(&client->dev,
a86854d0 KC	386	chip->bits, sizeof(struct pca955x_led),
ed1f4b96 CLG	387	GFP_KERNEL);
	388	if (!pdata->leds)
	389	return ERR_PTR(-ENOMEM);
	390
967f69de	391	device_for_each_child_node(&client->dev, child) {
ed1f4b96 CLG	392	const char *name;
	393	u32 reg;
	394	int res;
	395
967f69de	396	res = fwnode_property_read_u32(child, "reg", &reg);
ed1f4b96 CLG	397	if ((res != 0) \|\| (reg >= chip->bits))
	398	continue;
	399
967f69de AS	400	res = fwnode_property_read_string(child, "label", &name);
	401	if ((res != 0) && is_of_node(child))
	402	name = to_of_node(child)->name;
ed1f4b96 CLG	403
	404	snprintf(pdata->leds[reg].name, sizeof(pdata->leds[reg].name),
	405	"%s", name);
	406
561099a1	407	pdata->leds[reg].type = PCA955X_TYPE_LED;
967f69de AS	408	fwnode_property_read_u32(child, "type", &pdata->leds[reg].type);
967f69de AS	409	fwnode_property_read_string(child, "linux,default-trigger",
ed1f4b96 CLG	410	&pdata->leds[reg].default_trigger);
	411	}
	412
	413	pdata->num_leds = chip->bits;
	414
	415	return pdata;
	416	}
	417
	418	static const struct of_device_id of_pca955x_match[] = {
	419	{ .compatible = "nxp,pca9550", .data = (void *)pca9550 },
	420	{ .compatible = "nxp,pca9551", .data = (void *)pca9551 },
	421	{ .compatible = "nxp,pca9552", .data = (void *)pca9552 },
46de3adb	422	{ .compatible = "ibm,pca9552", .data = (void *)ibm_pca9552 },
ed1f4b96 CLG	423	{ .compatible = "nxp,pca9553", .data = (void *)pca9553 },
	424	{},
	425	};
ed1f4b96	426	MODULE_DEVICE_TABLE(of, of_pca955x_match);
ed1f4b96	427
98ea1ea2	428	static int pca955x_probe(struct i2c_client *client,
f46e9203 NC	429	const struct i2c_device_id *id)
f46e9203 NC	430	{
e7e11d8b AS	431	struct pca955x *pca955x;
e7e11d8b AS	432	struct pca955x_led *pca955x_led;
f46e9203 NC	433	struct pca955x_chipdef *chip;
f46e9203 NC	434	struct i2c_adapter *adapter;
95bf14bf	435	int i, err;
ed1f4b96	436	struct pca955x_platform_data *pdata;
561099a1	437	int ngpios = 0;
f46e9203	438
5b6cd445	439	chip = &pca955x_chipdefs[id->driver_data];
1c57d9bd	440	adapter = client->adapter;
87aae1ea	441	pdata = dev_get_platdata(&client->dev);
ed1f4b96	442	if (!pdata) {
967f69de	443	pdata = pca955x_get_pdata(client, chip);
ed1f4b96 CLG	444	if (IS_ERR(pdata))
	445	return PTR_ERR(pdata);
	446	}
f46e9203 NC	447
	448	/* Make sure the slave address / chip type combo given is possible */
	449	if ((client->addr & ~((1 << chip->slv_addr_shift) - 1)) !=
	450	chip->slv_addr) {
	451	dev_err(&client->dev, "invalid slave address %02x\n",
	452	client->addr);
	453	return -ENODEV;
	454	}
	455
b40b0c17	456	dev_info(&client->dev, "leds-pca955x: Using %s %d-bit LED driver at "
f46e9203	457	"slave address 0x%02x\n",
44b3e31d	458	client->name, chip->bits, client->addr);
f46e9203	459
aace34c0	460	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
f46e9203 NC	461	return -EIO;
f46e9203 NC	462
ed1f4b96 CLG	463	if (pdata->num_leds != chip->bits) {
	464	dev_err(&client->dev,
	465	"board info claims %d LEDs on a %d-bit chip\n",
	466	pdata->num_leds, chip->bits);
	467	return -ENODEV;
f46e9203 NC	468	}
f46e9203 NC	469
73759f6a	470	pca955x = devm_kzalloc(&client->dev, sizeof(*pca955x), GFP_KERNEL);
95bf14bf SW	471	if (!pca955x)
	472	return -ENOMEM;
	473
a86854d0 KC	474	pca955x->leds = devm_kcalloc(&client->dev,
a86854d0 KC	475	chip->bits, sizeof(*pca955x_led), GFP_KERNEL);
73759f6a BW	476	if (!pca955x->leds)
73759f6a BW	477	return -ENOMEM;
e7e11d8b	478
95bf14bf SW	479	i2c_set_clientdata(client, pca955x);
95bf14bf SW	480
e7e11d8b AS	481	mutex_init(&pca955x->lock);
	482	pca955x->client = client;
	483	pca955x->chipdef = chip;
	484
f46e9203	485	for (i = 0; i < chip->bits; i++) {
e7e11d8b AS	486	pca955x_led = &pca955x->leds[i];
	487	pca955x_led->led_num = i;
	488	pca955x_led->pca955x = pca955x;
561099a1 CLG	489	pca955x_led->type = pdata->leds[i].type;
	490
	491	switch (pca955x_led->type) {
	492	case PCA955X_TYPE_NONE:
	493	break;
	494	case PCA955X_TYPE_GPIO:
	495	ngpios++;
	496	break;
	497	case PCA955X_TYPE_LED:
	498	/*
	499	* Platform data can specify LED names and
	500	* default triggers
	501	*/
390c97dc JA	502	if (pdata->leds[i].name[0] == '\0')
	503	snprintf(pdata->leds[i].name,
	504	sizeof(pdata->leds[i].name), "%d", i);
	505
	506	snprintf(pca955x_led->name,
	507	sizeof(pca955x_led->name), "pca955x:%s",
	508	pdata->leds[i].name);
	509
f46e9203	510	if (pdata->leds[i].default_trigger)
e7e11d8b	511	pca955x_led->led_cdev.default_trigger =
f46e9203	512	pdata->leds[i].default_trigger;
f46e9203	513
561099a1 CLG	514	pca955x_led->led_cdev.name = pca955x_led->name;
	515	pca955x_led->led_cdev.brightness_set_blocking =
	516	pca955x_led_set;
f46e9203	517
561099a1 CLG	518	err = devm_led_classdev_register(&client->dev,
	519	&pca955x_led->led_cdev);
	520	if (err)
	521	return err;
f46e9203	522
561099a1	523	/* Turn off LED */
1591caf2 CLG	524	err = pca955x_led_set(&pca955x_led->led_cdev, LED_OFF);
	525	if (err)
	526	return err;
561099a1 CLG	527	}
561099a1 CLG	528	}
f46e9203 NC	529
f46e9203 NC	530	/* PWM0 is used for half brightness or 50% duty cycle */
1591caf2 CLG	531	err = pca955x_write_pwm(client, 0, 255 - LED_HALF);
	532	if (err)
	533	return err;
f46e9203 NC	534
f46e9203 NC	535	/* PWM1 is used for variable brightness, default to OFF */
1591caf2 CLG	536	err = pca955x_write_pwm(client, 1, 0);
	537	if (err)
	538	return err;
f46e9203 NC	539
f46e9203 NC	540	/* Set to fast frequency so we do not see flashing */
1591caf2 CLG	541	err = pca955x_write_psc(client, 0, 0);
	542	if (err)
	543	return err;
	544	err = pca955x_write_psc(client, 1, 0);
	545	if (err)
	546	return err;
f46e9203	547
561099a1 CLG	548	#ifdef CONFIG_LEDS_PCA955X_GPIO
	549	if (ngpios) {
	550	pca955x->gpio.label = "gpio-pca955x";
	551	pca955x->gpio.direction_input = pca955x_gpio_direction_input;
	552	pca955x->gpio.direction_output = pca955x_gpio_direction_output;
	553	pca955x->gpio.set = pca955x_gpio_set_value;
	554	pca955x->gpio.get = pca955x_gpio_get_value;
	555	pca955x->gpio.request = pca955x_gpio_request_pin;
	556	pca955x->gpio.can_sleep = 1;
	557	pca955x->gpio.base = -1;
	558	pca955x->gpio.ngpio = ngpios;
	559	pca955x->gpio.parent = &client->dev;
	560	pca955x->gpio.owner = THIS_MODULE;
	561
	562	err = devm_gpiochip_add_data(&client->dev, &pca955x->gpio,
	563	pca955x);
	564	if (err) {
	565	/* Use data->gpio.dev as a flag for freeing gpiochip */
	566	pca955x->gpio.parent = NULL;
	567	dev_warn(&client->dev, "could not add gpiochip\n");
	568	return err;
	569	}
	570	dev_info(&client->dev, "gpios %i...%i\n",
	571	pca955x->gpio.base, pca955x->gpio.base +
	572	pca955x->gpio.ngpio - 1);
	573	}
	574	#endif
	575
f46e9203	576	return 0;
f46e9203 NC	577	}
	578
	579	static struct i2c_driver pca955x_driver = {
	580	.driver = {
	581	.name = "leds-pca955x",
967f69de	582	.of_match_table = of_pca955x_match,
f46e9203 NC	583	},
f46e9203 NC	584	.probe = pca955x_probe,
f46e9203 NC	585	.id_table = pca955x_id,
	586	};
	587
09a0d183	588	module_i2c_driver(pca955x_driver);
f46e9203 NC	589
	590	MODULE_AUTHOR("Nate Case <ncase@xes-inc.com>");
	591	MODULE_DESCRIPTION("PCA955x LED driver");
	592	MODULE_LICENSE("GPL v2");