[linux-2.6-block.git] / drivers / pwm / pwm-pca9685.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Driver for PCA9685 16-channel 12-bit PWM LED controller
 *
 * Copyright (C) 2013 Steffen Trumtrar <s.trumtrar@pengutronix.de>
 * Copyright (C) 2015 Clemens Gruber <clemens.gruber@pqgruber.com>
 *
 * based on the pwm-twl-led.c driver
 */

#include <linux/acpi.h>
#include <linux/gpio/driver.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/platform_device.h>
#include <linux/property.h>
#include <linux/pwm.h>
#include <linux/regmap.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/pm_runtime.h>

/*
 * Because the PCA9685 has only one prescaler per chip, changing the period of
 * one channel affects the period of all 16 PWM outputs!
 * However, the ratio between each configured duty cycle and the chip-wide
 * period remains constant, because the OFF time is set in proportion to the
 * counter range.
 */

#define PCA9685_MODE1		0x00
#define PCA9685_MODE2		0x01
#define PCA9685_SUBADDR1	0x02
#define PCA9685_SUBADDR2	0x03
#define PCA9685_SUBADDR3	0x04
#define PCA9685_ALLCALLADDR	0x05
#define PCA9685_LEDX_ON_L	0x06
#define PCA9685_LEDX_ON_H	0x07
#define PCA9685_LEDX_OFF_L	0x08
#define PCA9685_LEDX_OFF_H	0x09

#define PCA9685_ALL_LED_ON_L	0xFA
#define PCA9685_ALL_LED_ON_H	0xFB
#define PCA9685_ALL_LED_OFF_L	0xFC
#define PCA9685_ALL_LED_OFF_H	0xFD
#define PCA9685_PRESCALE	0xFE

#define PCA9685_PRESCALE_MIN	0x03	/* => max. frequency of 1526 Hz */
#define PCA9685_PRESCALE_MAX	0xFF	/* => min. frequency of 24 Hz */

#define PCA9685_COUNTER_RANGE	4096
#define PCA9685_DEFAULT_PERIOD	5000000	/* Default period_ns = 1/200 Hz */
#define PCA9685_OSC_CLOCK_MHZ	25	/* Internal oscillator with 25 MHz */

#define PCA9685_NUMREGS		0xFF
#define PCA9685_MAXCHAN		0x10

#define LED_FULL		(1 << 4)
#define MODE1_SLEEP		(1 << 4)
#define MODE2_INVRT		(1 << 4)
#define MODE2_OUTDRV		(1 << 2)

#define LED_N_ON_H(N)	(PCA9685_LEDX_ON_H + (4 * (N)))
#define LED_N_ON_L(N)	(PCA9685_LEDX_ON_L + (4 * (N)))
#define LED_N_OFF_H(N)	(PCA9685_LEDX_OFF_H + (4 * (N)))
#define LED_N_OFF_L(N)	(PCA9685_LEDX_OFF_L + (4 * (N)))

struct pca9685 {
	struct pwm_chip chip;
	struct regmap *regmap;
	int duty_ns;
	int period_ns;
#if IS_ENABLED(CONFIG_GPIOLIB)
	struct mutex lock;
	struct gpio_chip gpio;
#endif
};

static inline struct pca9685 *to_pca(struct pwm_chip *chip)
{
	return container_of(chip, struct pca9685, chip);
}

#if IS_ENABLED(CONFIG_GPIOLIB)
static int pca9685_pwm_gpio_request(struct gpio_chip *gpio, unsigned int offset)
{
	struct pca9685 *pca = gpiochip_get_data(gpio);
	struct pwm_device *pwm;

	mutex_lock(&pca->lock);

	pwm = &pca->chip.pwms[offset];

	if (pwm->flags & (PWMF_REQUESTED | PWMF_EXPORTED)) {
		mutex_unlock(&pca->lock);
		return -EBUSY;
	}

	pwm_set_chip_data(pwm, (void *)1);

	mutex_unlock(&pca->lock);
	pm_runtime_get_sync(pca->chip.dev);
	return 0;
}

static bool pca9685_pwm_is_gpio(struct pca9685 *pca, struct pwm_device *pwm)
{
	bool is_gpio = false;

	mutex_lock(&pca->lock);

	if (pwm->hwpwm >= PCA9685_MAXCHAN) {
		unsigned int i;

		/*
		 * Check if any of the GPIOs are requested and in that case
		 * prevent using the "all LEDs" channel.
		 */
		for (i = 0; i < pca->gpio.ngpio; i++)
			if (gpiochip_is_requested(&pca->gpio, i)) {
				is_gpio = true;
				break;
			}
	} else if (pwm_get_chip_data(pwm)) {
		is_gpio = true;
	}

	mutex_unlock(&pca->lock);
	return is_gpio;
}

static int pca9685_pwm_gpio_get(struct gpio_chip *gpio, unsigned int offset)
{
	struct pca9685 *pca = gpiochip_get_data(gpio);
	struct pwm_device *pwm = &pca->chip.pwms[offset];
	unsigned int value;

	regmap_read(pca->regmap, LED_N_ON_H(pwm->hwpwm), &value);

	return value & LED_FULL;
}

static void pca9685_pwm_gpio_set(struct gpio_chip *gpio, unsigned int offset,
				 int value)
{
	struct pca9685 *pca = gpiochip_get_data(gpio);
	struct pwm_device *pwm = &pca->chip.pwms[offset];
	unsigned int on = value ? LED_FULL : 0;

	/* Clear both OFF registers */
	regmap_write(pca->regmap, LED_N_OFF_L(pwm->hwpwm), 0);
	regmap_write(pca->regmap, LED_N_OFF_H(pwm->hwpwm), 0);

	/* Set the full ON bit */
	regmap_write(pca->regmap, LED_N_ON_H(pwm->hwpwm), on);
}

static void pca9685_pwm_gpio_free(struct gpio_chip *gpio, unsigned int offset)
{
	struct pca9685 *pca = gpiochip_get_data(gpio);
	struct pwm_device *pwm;

	pca9685_pwm_gpio_set(gpio, offset, 0);
	pm_runtime_put(pca->chip.dev);
	mutex_lock(&pca->lock);
	pwm = &pca->chip.pwms[offset];
	mutex_unlock(&pca->lock);
}

static int pca9685_pwm_gpio_get_direction(struct gpio_chip *chip,
					  unsigned int offset)
{
	/* Always out */
	return 0;
}

static int pca9685_pwm_gpio_direction_input(struct gpio_chip *gpio,
					    unsigned int offset)
{
	return -EINVAL;
}

static int pca9685_pwm_gpio_direction_output(struct gpio_chip *gpio,
					     unsigned int offset, int value)
{
	pca9685_pwm_gpio_set(gpio, offset, value);

	return 0;
}

/*
 * The PCA9685 has a bit for turning the PWM output full off or on. Some
 * boards like Intel Galileo actually uses these as normal GPIOs so we
 * expose a GPIO chip here which can exclusively take over the underlying
 * PWM channel.
 */
static int pca9685_pwm_gpio_probe(struct pca9685 *pca)
{
	struct device *dev = pca->chip.dev;

	mutex_init(&pca->lock);

	pca->gpio.label = dev_name(dev);
	pca->gpio.parent = dev;
	pca->gpio.request = pca9685_pwm_gpio_request;
	pca->gpio.free = pca9685_pwm_gpio_free;
	pca->gpio.get_direction = pca9685_pwm_gpio_get_direction;
	pca->gpio.direction_input = pca9685_pwm_gpio_direction_input;
	pca->gpio.direction_output = pca9685_pwm_gpio_direction_output;
	pca->gpio.get = pca9685_pwm_gpio_get;
	pca->gpio.set = pca9685_pwm_gpio_set;
	pca->gpio.base = -1;
	pca->gpio.ngpio = PCA9685_MAXCHAN;
	pca->gpio.can_sleep = true;

	return devm_gpiochip_add_data(dev, &pca->gpio, pca);
}
#else
static inline bool pca9685_pwm_is_gpio(struct pca9685 *pca,
				       struct pwm_device *pwm)
{
	return false;
}

static inline int pca9685_pwm_gpio_probe(struct pca9685 *pca)
{
	return 0;
}
#endif

static void pca9685_set_sleep_mode(struct pca9685 *pca, bool enable)
{
	regmap_update_bits(pca->regmap, PCA9685_MODE1,
			   MODE1_SLEEP, enable ? MODE1_SLEEP : 0);
	if (!enable) {
		/* Wait 500us for the oscillator to be back up */
		udelay(500);
	}
}

static int pca9685_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
			      int duty_ns, int period_ns)
{
	struct pca9685 *pca = to_pca(chip);
	unsigned long long duty;
	unsigned int reg;
	int prescale;

	if (period_ns != pca->period_ns) {
		prescale = DIV_ROUND_CLOSEST(PCA9685_OSC_CLOCK_MHZ * period_ns,
					     PCA9685_COUNTER_RANGE * 1000) - 1;

		if (prescale >= PCA9685_PRESCALE_MIN &&
			prescale <= PCA9685_PRESCALE_MAX) {
			/*
			 * putting the chip briefly into SLEEP mode
			 * at this point won't interfere with the
			 * pm_runtime framework, because the pm_runtime
			 * state is guaranteed active here.
			 */
			/* Put chip into sleep mode */
			pca9685_set_sleep_mode(pca, true);

			/* Change the chip-wide output frequency */
			regmap_write(pca->regmap, PCA9685_PRESCALE, prescale);

			/* Wake the chip up */
			pca9685_set_sleep_mode(pca, false);

			pca->period_ns = period_ns;
		} else {
			dev_err(chip->dev,
				"prescaler not set: period out of bounds!\n");
			return -EINVAL;
		}
	}

	pca->duty_ns = duty_ns;

	if (duty_ns < 1) {
		if (pwm->hwpwm >= PCA9685_MAXCHAN)
			reg = PCA9685_ALL_LED_OFF_H;
		else
			reg = LED_N_OFF_H(pwm->hwpwm);

		regmap_write(pca->regmap, reg, LED_FULL);

		return 0;
	}

	if (duty_ns == period_ns) {
		/* Clear both OFF registers */
		if (pwm->hwpwm >= PCA9685_MAXCHAN)
			reg = PCA9685_ALL_LED_OFF_L;
		else
			reg = LED_N_OFF_L(pwm->hwpwm);

		regmap_write(pca->regmap, reg, 0x0);

		if (pwm->hwpwm >= PCA9685_MAXCHAN)
			reg = PCA9685_ALL_LED_OFF_H;
		else
			reg = LED_N_OFF_H(pwm->hwpwm);

		regmap_write(pca->regmap, reg, 0x0);

		/* Set the full ON bit */
		if (pwm->hwpwm >= PCA9685_MAXCHAN)
			reg = PCA9685_ALL_LED_ON_H;
		else
			reg = LED_N_ON_H(pwm->hwpwm);

		regmap_write(pca->regmap, reg, LED_FULL);

		return 0;
	}

	duty = PCA9685_COUNTER_RANGE * (unsigned long long)duty_ns;
	duty = DIV_ROUND_UP_ULL(duty, period_ns);

	if (pwm->hwpwm >= PCA9685_MAXCHAN)
		reg = PCA9685_ALL_LED_OFF_L;
	else
		reg = LED_N_OFF_L(pwm->hwpwm);

	regmap_write(pca->regmap, reg, (int)duty & 0xff);

	if (pwm->hwpwm >= PCA9685_MAXCHAN)
		reg = PCA9685_ALL_LED_OFF_H;
	else
		reg = LED_N_OFF_H(pwm->hwpwm);

	regmap_write(pca->regmap, reg, ((int)duty >> 8) & 0xf);

	/* Clear the full ON bit, otherwise the set OFF time has no effect */
	if (pwm->hwpwm >= PCA9685_MAXCHAN)
		reg = PCA9685_ALL_LED_ON_H;
	else
		reg = LED_N_ON_H(pwm->hwpwm);

	regmap_write(pca->regmap, reg, 0);

	return 0;
}

static int pca9685_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
{
	struct pca9685 *pca = to_pca(chip);
	unsigned int reg;

	/*
	 * The PWM subsystem does not support a pre-delay.
	 * So, set the ON-timeout to 0
	 */
	if (pwm->hwpwm >= PCA9685_MAXCHAN)
		reg = PCA9685_ALL_LED_ON_L;
	else
		reg = LED_N_ON_L(pwm->hwpwm);

	regmap_write(pca->regmap, reg, 0);

	if (pwm->hwpwm >= PCA9685_MAXCHAN)
		reg = PCA9685_ALL_LED_ON_H;
	else
		reg = LED_N_ON_H(pwm->hwpwm);

	regmap_write(pca->regmap, reg, 0);

	/*
	 * Clear the full-off bit.
	 * It has precedence over the others and must be off.
	 */
	if (pwm->hwpwm >= PCA9685_MAXCHAN)
		reg = PCA9685_ALL_LED_OFF_H;
	else
		reg = LED_N_OFF_H(pwm->hwpwm);

	regmap_update_bits(pca->regmap, reg, LED_FULL, 0x0);

	return 0;
}

static void pca9685_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
{
	struct pca9685 *pca = to_pca(chip);
	unsigned int reg;

	if (pwm->hwpwm >= PCA9685_MAXCHAN)
		reg = PCA9685_ALL_LED_OFF_H;
	else
		reg = LED_N_OFF_H(pwm->hwpwm);

	regmap_write(pca->regmap, reg, LED_FULL);

	/* Clear the LED_OFF counter. */
	if (pwm->hwpwm >= PCA9685_MAXCHAN)
		reg = PCA9685_ALL_LED_OFF_L;
	else
		reg = LED_N_OFF_L(pwm->hwpwm);

	regmap_write(pca->regmap, reg, 0x0);
}

static int pca9685_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
{
	struct pca9685 *pca = to_pca(chip);

	if (pca9685_pwm_is_gpio(pca, pwm))
		return -EBUSY;
	pm_runtime_get_sync(chip->dev);

	return 0;
}

static void pca9685_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
{
	pca9685_pwm_disable(chip, pwm);
	pm_runtime_put(chip->dev);
}

static const struct pwm_ops pca9685_pwm_ops = {
	.enable = pca9685_pwm_enable,
	.disable = pca9685_pwm_disable,
	.config = pca9685_pwm_config,
	.request = pca9685_pwm_request,
	.free = pca9685_pwm_free,
	.owner = THIS_MODULE,
};

static const struct regmap_config pca9685_regmap_i2c_config = {
	.reg_bits = 8,
	.val_bits = 8,
	.max_register = PCA9685_NUMREGS,
	.cache_type = REGCACHE_NONE,
};

static int pca9685_pwm_probe(struct i2c_client *client,
				const struct i2c_device_id *id)
{
	struct pca9685 *pca;
	int ret;
	int mode2;

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

	pca->regmap = devm_regmap_init_i2c(client, &pca9685_regmap_i2c_config);
	if (IS_ERR(pca->regmap)) {
		ret = PTR_ERR(pca->regmap);
		dev_err(&client->dev, "Failed to initialize register map: %d\n",
			ret);
		return ret;
	}
	pca->duty_ns = 0;
	pca->period_ns = PCA9685_DEFAULT_PERIOD;

	i2c_set_clientdata(client, pca);

	regmap_read(pca->regmap, PCA9685_MODE2, &mode2);

	if (device_property_read_bool(&client->dev, "invert"))
		mode2 |= MODE2_INVRT;
	else
		mode2 &= ~MODE2_INVRT;

	if (device_property_read_bool(&client->dev, "open-drain"))
		mode2 &= ~MODE2_OUTDRV;
	else
		mode2 |= MODE2_OUTDRV;

	regmap_write(pca->regmap, PCA9685_MODE2, mode2);

	/* clear all "full off" bits */
	regmap_write(pca->regmap, PCA9685_ALL_LED_OFF_L, 0);
	regmap_write(pca->regmap, PCA9685_ALL_LED_OFF_H, 0);

	pca->chip.ops = &pca9685_pwm_ops;
	/* add an extra channel for ALL_LED */
	pca->chip.npwm = PCA9685_MAXCHAN + 1;

	pca->chip.dev = &client->dev;
	pca->chip.base = -1;

	ret = pwmchip_add(&pca->chip);
	if (ret < 0)
		return ret;

	ret = pca9685_pwm_gpio_probe(pca);
	if (ret < 0) {
		pwmchip_remove(&pca->chip);
		return ret;
	}

	/* the chip comes out of power-up in the active state */
	pm_runtime_set_active(&client->dev);
	/*
	 * enable will put the chip into suspend, which is what we
	 * want as all outputs are disabled at this point
	 */
	pm_runtime_enable(&client->dev);

	return 0;
}

static int pca9685_pwm_remove(struct i2c_client *client)
{
	struct pca9685 *pca = i2c_get_clientdata(client);
	int ret;

	ret = pwmchip_remove(&pca->chip);
	if (ret)
		return ret;
	pm_runtime_disable(&client->dev);
	return 0;
}

#ifdef CONFIG_PM
static int pca9685_pwm_runtime_suspend(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct pca9685 *pca = i2c_get_clientdata(client);

	pca9685_set_sleep_mode(pca, true);
	return 0;
}

static int pca9685_pwm_runtime_resume(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct pca9685 *pca = i2c_get_clientdata(client);

	pca9685_set_sleep_mode(pca, false);
	return 0;
}
#endif

static const struct i2c_device_id pca9685_id[] = {
	{ "pca9685", 0 },
	{ /* sentinel */ },
};
MODULE_DEVICE_TABLE(i2c, pca9685_id);

#ifdef CONFIG_ACPI
static const struct acpi_device_id pca9685_acpi_ids[] = {
	{ "INT3492", 0 },
	{ /* sentinel */ },
};
MODULE_DEVICE_TABLE(acpi, pca9685_acpi_ids);
#endif

#ifdef CONFIG_OF
static const struct of_device_id pca9685_dt_ids[] = {
	{ .compatible = "nxp,pca9685-pwm", },
	{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, pca9685_dt_ids);
#endif

static const struct dev_pm_ops pca9685_pwm_pm = {
	SET_RUNTIME_PM_OPS(pca9685_pwm_runtime_suspend,
			   pca9685_pwm_runtime_resume, NULL)
};

static struct i2c_driver pca9685_i2c_driver = {
	.driver = {
		.name = "pca9685-pwm",
		.acpi_match_table = ACPI_PTR(pca9685_acpi_ids),
		.of_match_table = of_match_ptr(pca9685_dt_ids),
		.pm = &pca9685_pwm_pm,
	},
	.probe = pca9685_pwm_probe,
	.remove = pca9685_pwm_remove,
	.id_table = pca9685_id,
};

module_i2c_driver(pca9685_i2c_driver);

MODULE_AUTHOR("Steffen Trumtrar <s.trumtrar@pengutronix.de>");
MODULE_DESCRIPTION("PWM driver for PCA9685");
MODULE_LICENSE("GPL");
Commit	Line	Data
caab277b	1	// SPDX-License-Identifier: GPL-2.0-only
88b613e6 ST	2	/*
	3	* Driver for PCA9685 16-channel 12-bit PWM LED controller
	4	*
	5	* Copyright (C) 2013 Steffen Trumtrar <s.trumtrar@pengutronix.de>
01ec8472	6	* Copyright (C) 2015 Clemens Gruber <clemens.gruber@pqgruber.com>
88b613e6 ST	7	*
88b613e6 ST	8	* based on the pwm-twl-led.c driver
88b613e6 ST	9	*/
88b613e6 ST	10
912b8439	11	#include <linux/acpi.h>
bccec89f	12	#include <linux/gpio/driver.h>
88b613e6 ST	13	#include <linux/i2c.h>
88b613e6 ST	14	#include <linux/module.h>
bccec89f	15	#include <linux/mutex.h>
88b613e6	16	#include <linux/platform_device.h>
912b8439	17	#include <linux/property.h>
88b613e6 ST	18	#include <linux/pwm.h>
	19	#include <linux/regmap.h>
	20	#include <linux/slab.h>
01ec8472	21	#include <linux/delay.h>
c40c461e	22	#include <linux/pm_runtime.h>
01ec8472 CG	23
	24	/*
	25	* Because the PCA9685 has only one prescaler per chip, changing the period of
	26	* one channel affects the period of all 16 PWM outputs!
	27	* However, the ratio between each configured duty cycle and the chip-wide
	28	* period remains constant, because the OFF time is set in proportion to the
	29	* counter range.
	30	*/
88b613e6 ST	31
	32	#define PCA9685_MODE1 0x00
	33	#define PCA9685_MODE2 0x01
	34	#define PCA9685_SUBADDR1 0x02
	35	#define PCA9685_SUBADDR2 0x03
	36	#define PCA9685_SUBADDR3 0x04
	37	#define PCA9685_ALLCALLADDR 0x05
	38	#define PCA9685_LEDX_ON_L 0x06
	39	#define PCA9685_LEDX_ON_H 0x07
	40	#define PCA9685_LEDX_OFF_L 0x08
	41	#define PCA9685_LEDX_OFF_H 0x09
	42
	43	#define PCA9685_ALL_LED_ON_L 0xFA
	44	#define PCA9685_ALL_LED_ON_H 0xFB
	45	#define PCA9685_ALL_LED_OFF_L 0xFC
	46	#define PCA9685_ALL_LED_OFF_H 0xFD
	47	#define PCA9685_PRESCALE 0xFE
	48
01ec8472 CG	49	#define PCA9685_PRESCALE_MIN 0x03 /* => max. frequency of 1526 Hz */
	50	#define PCA9685_PRESCALE_MAX 0xFF /* => min. frequency of 24 Hz */
	51
	52	#define PCA9685_COUNTER_RANGE 4096
	53	#define PCA9685_DEFAULT_PERIOD 5000000 /* Default period_ns = 1/200 Hz */
	54	#define PCA9685_OSC_CLOCK_MHZ 25 /* Internal oscillator with 25 MHz */
	55
88b613e6 ST	56	#define PCA9685_NUMREGS 0xFF
	57	#define PCA9685_MAXCHAN 0x10
	58
	59	#define LED_FULL (1 << 4)
	60	#define MODE1_SLEEP (1 << 4)
	61	#define MODE2_INVRT (1 << 4)
	62	#define MODE2_OUTDRV (1 << 2)
	63
	64	#define LED_N_ON_H(N) (PCA9685_LEDX_ON_H + (4 * (N)))
	65	#define LED_N_ON_L(N) (PCA9685_LEDX_ON_L + (4 * (N)))
	66	#define LED_N_OFF_H(N) (PCA9685_LEDX_OFF_H + (4 * (N)))
	67	#define LED_N_OFF_L(N) (PCA9685_LEDX_OFF_L + (4 * (N)))
	68
	69	struct pca9685 {
	70	struct pwm_chip chip;
	71	struct regmap *regmap;
01ec8472 CG	72	int duty_ns;
01ec8472 CG	73	int period_ns;
bccec89f MW	74	#if IS_ENABLED(CONFIG_GPIOLIB)
	75	struct mutex lock;
	76	struct gpio_chip gpio;
	77	#endif
88b613e6 ST	78	};
	79
	80	static inline struct pca9685 to_pca(struct pwm_chip chip)
	81	{
	82	return container_of(chip, struct pca9685, chip);
	83	}
	84
bccec89f MW	85	#if IS_ENABLED(CONFIG_GPIOLIB)
	86	static int pca9685_pwm_gpio_request(struct gpio_chip *gpio, unsigned int offset)
	87	{
	88	struct pca9685 *pca = gpiochip_get_data(gpio);
	89	struct pwm_device *pwm;
	90
	91	mutex_lock(&pca->lock);
	92
	93	pwm = &pca->chip.pwms[offset];
	94
	95	if (pwm->flags & (PWMF_REQUESTED \| PWMF_EXPORTED)) {
	96	mutex_unlock(&pca->lock);
	97	return -EBUSY;
	98	}
	99
	100	pwm_set_chip_data(pwm, (void *)1);
	101
	102	mutex_unlock(&pca->lock);
c40c461e	103	pm_runtime_get_sync(pca->chip.dev);
bccec89f MW	104	return 0;
	105	}
	106
bccec89f MW	107	static bool pca9685_pwm_is_gpio(struct pca9685 pca, struct pwm_device pwm)
	108	{
	109	bool is_gpio = false;
	110
	111	mutex_lock(&pca->lock);
	112
	113	if (pwm->hwpwm >= PCA9685_MAXCHAN) {
	114	unsigned int i;
	115
	116	/*
	117	* Check if any of the GPIOs are requested and in that case
	118	* prevent using the "all LEDs" channel.
	119	*/
	120	for (i = 0; i < pca->gpio.ngpio; i++)
	121	if (gpiochip_is_requested(&pca->gpio, i)) {
	122	is_gpio = true;
	123	break;
	124	}
	125	} else if (pwm_get_chip_data(pwm)) {
	126	is_gpio = true;
	127	}
	128
	129	mutex_unlock(&pca->lock);
	130	return is_gpio;
	131	}
	132
	133	static int pca9685_pwm_gpio_get(struct gpio_chip *gpio, unsigned int offset)
	134	{
	135	struct pca9685 *pca = gpiochip_get_data(gpio);
	136	struct pwm_device *pwm = &pca->chip.pwms[offset];
	137	unsigned int value;
	138
	139	regmap_read(pca->regmap, LED_N_ON_H(pwm->hwpwm), &value);
	140
	141	return value & LED_FULL;
	142	}
	143
	144	static void pca9685_pwm_gpio_set(struct gpio_chip *gpio, unsigned int offset,
	145	int value)
	146	{
	147	struct pca9685 *pca = gpiochip_get_data(gpio);
	148	struct pwm_device *pwm = &pca->chip.pwms[offset];
	149	unsigned int on = value ? LED_FULL : 0;
	150
	151	/* Clear both OFF registers */
	152	regmap_write(pca->regmap, LED_N_OFF_L(pwm->hwpwm), 0);
	153	regmap_write(pca->regmap, LED_N_OFF_H(pwm->hwpwm), 0);
	154
	155	/* Set the full ON bit */
	156	regmap_write(pca->regmap, LED_N_ON_H(pwm->hwpwm), on);
	157	}
	158
c40c461e SVA	159	static void pca9685_pwm_gpio_free(struct gpio_chip *gpio, unsigned int offset)
	160	{
	161	struct pca9685 *pca = gpiochip_get_data(gpio);
	162	struct pwm_device *pwm;
	163
	164	pca9685_pwm_gpio_set(gpio, offset, 0);
	165	pm_runtime_put(pca->chip.dev);
	166	mutex_lock(&pca->lock);
	167	pwm = &pca->chip.pwms[offset];
c40c461e SVA	168	mutex_unlock(&pca->lock);
	169	}
	170
bccec89f MW	171	static int pca9685_pwm_gpio_get_direction(struct gpio_chip *chip,
	172	unsigned int offset)
	173	{
	174	/* Always out */
	175	return 0;
	176	}
	177
	178	static int pca9685_pwm_gpio_direction_input(struct gpio_chip *gpio,
	179	unsigned int offset)
	180	{
	181	return -EINVAL;
	182	}
	183
	184	static int pca9685_pwm_gpio_direction_output(struct gpio_chip *gpio,
	185	unsigned int offset, int value)
	186	{
	187	pca9685_pwm_gpio_set(gpio, offset, value);
	188
	189	return 0;
	190	}
	191
	192	/*
	193	* The PCA9685 has a bit for turning the PWM output full off or on. Some
	194	* boards like Intel Galileo actually uses these as normal GPIOs so we
	195	* expose a GPIO chip here which can exclusively take over the underlying
	196	* PWM channel.
	197	*/
	198	static int pca9685_pwm_gpio_probe(struct pca9685 *pca)
	199	{
	200	struct device *dev = pca->chip.dev;
	201
	202	mutex_init(&pca->lock);
	203
	204	pca->gpio.label = dev_name(dev);
	205	pca->gpio.parent = dev;
	206	pca->gpio.request = pca9685_pwm_gpio_request;
	207	pca->gpio.free = pca9685_pwm_gpio_free;
	208	pca->gpio.get_direction = pca9685_pwm_gpio_get_direction;
	209	pca->gpio.direction_input = pca9685_pwm_gpio_direction_input;
	210	pca->gpio.direction_output = pca9685_pwm_gpio_direction_output;
	211	pca->gpio.get = pca9685_pwm_gpio_get;
	212	pca->gpio.set = pca9685_pwm_gpio_set;
	213	pca->gpio.base = -1;
	214	pca->gpio.ngpio = PCA9685_MAXCHAN;
	215	pca->gpio.can_sleep = true;
	216
	217	return devm_gpiochip_add_data(dev, &pca->gpio, pca);
	218	}
	219	#else
	220	static inline bool pca9685_pwm_is_gpio(struct pca9685 *pca,
	221	struct pwm_device *pwm)
	222	{
	223	return false;
	224	}
	225
	226	static inline int pca9685_pwm_gpio_probe(struct pca9685 *pca)
	227	{
	228	return 0;
	229	}
	230	#endif
	231
0829326a	232	static void pca9685_set_sleep_mode(struct pca9685 *pca, bool enable)
c40c461e SVA	233	{
c40c461e SVA	234	regmap_update_bits(pca->regmap, PCA9685_MODE1,
0829326a SVA	235	MODE1_SLEEP, enable ? MODE1_SLEEP : 0);
0829326a SVA	236	if (!enable) {
c40c461e SVA	237	/* Wait 500us for the oscillator to be back up */
	238	udelay(500);
	239	}
	240	}
	241
88b613e6 ST	242	static int pca9685_pwm_config(struct pwm_chip chip, struct pwm_device pwm,
	243	int duty_ns, int period_ns)
	244	{
	245	struct pca9685 *pca = to_pca(chip);
	246	unsigned long long duty;
	247	unsigned int reg;
01ec8472 CG	248	int prescale;
	249
	250	if (period_ns != pca->period_ns) {
	251	prescale = DIV_ROUND_CLOSEST(PCA9685_OSC_CLOCK_MHZ * period_ns,
	252	PCA9685_COUNTER_RANGE * 1000) - 1;
	253
	254	if (prescale >= PCA9685_PRESCALE_MIN &&
	255	prescale <= PCA9685_PRESCALE_MAX) {
c40c461e SVA	256	/*
	257	* putting the chip briefly into SLEEP mode
	258	* at this point won't interfere with the
	259	* pm_runtime framework, because the pm_runtime
	260	* state is guaranteed active here.
	261	*/
01ec8472	262	/* Put chip into sleep mode */
0829326a	263	pca9685_set_sleep_mode(pca, true);
01ec8472 CG	264
	265	/* Change the chip-wide output frequency */
	266	regmap_write(pca->regmap, PCA9685_PRESCALE, prescale);
	267
	268	/* Wake the chip up */
0829326a	269	pca9685_set_sleep_mode(pca, false);
01ec8472 CG	270
01ec8472 CG	271	pca->period_ns = period_ns;
01ec8472 CG	272	} else {
	273	dev_err(chip->dev,
	274	"prescaler not set: period out of bounds!\n");
	275	return -EINVAL;
	276	}
	277	}
	278
	279	pca->duty_ns = duty_ns;
88b613e6 ST	280
	281	if (duty_ns < 1) {
	282	if (pwm->hwpwm >= PCA9685_MAXCHAN)
	283	reg = PCA9685_ALL_LED_OFF_H;
	284	else
	285	reg = LED_N_OFF_H(pwm->hwpwm);
	286
	287	regmap_write(pca->regmap, reg, LED_FULL);
	288
	289	return 0;
	290	}
	291
	292	if (duty_ns == period_ns) {
4a627b52 CG	293	/* Clear both OFF registers */
	294	if (pwm->hwpwm >= PCA9685_MAXCHAN)
	295	reg = PCA9685_ALL_LED_OFF_L;
	296	else
	297	reg = LED_N_OFF_L(pwm->hwpwm);
	298
	299	regmap_write(pca->regmap, reg, 0x0);
	300
	301	if (pwm->hwpwm >= PCA9685_MAXCHAN)
	302	reg = PCA9685_ALL_LED_OFF_H;
	303	else
	304	reg = LED_N_OFF_H(pwm->hwpwm);
	305
	306	regmap_write(pca->regmap, reg, 0x0);
	307
	308	/* Set the full ON bit */
88b613e6 ST	309	if (pwm->hwpwm >= PCA9685_MAXCHAN)
	310	reg = PCA9685_ALL_LED_ON_H;
	311	else
	312	reg = LED_N_ON_H(pwm->hwpwm);
	313
	314	regmap_write(pca->regmap, reg, LED_FULL);
	315
	316	return 0;
	317	}
	318
01ec8472	319	duty = PCA9685_COUNTER_RANGE * (unsigned long long)duty_ns;
88b613e6 ST	320	duty = DIV_ROUND_UP_ULL(duty, period_ns);
	321
	322	if (pwm->hwpwm >= PCA9685_MAXCHAN)
	323	reg = PCA9685_ALL_LED_OFF_L;
	324	else
	325	reg = LED_N_OFF_L(pwm->hwpwm);
	326
	327	regmap_write(pca->regmap, reg, (int)duty & 0xff);
	328
	329	if (pwm->hwpwm >= PCA9685_MAXCHAN)
	330	reg = PCA9685_ALL_LED_OFF_H;
	331	else
	332	reg = LED_N_OFF_H(pwm->hwpwm);
	333
	334	regmap_write(pca->regmap, reg, ((int)duty >> 8) & 0xf);
	335
4a627b52 CG	336	/* Clear the full ON bit, otherwise the set OFF time has no effect */
	337	if (pwm->hwpwm >= PCA9685_MAXCHAN)
	338	reg = PCA9685_ALL_LED_ON_H;
	339	else
	340	reg = LED_N_ON_H(pwm->hwpwm);
	341
	342	regmap_write(pca->regmap, reg, 0);
	343
88b613e6 ST	344	return 0;
	345	}
	346
	347	static int pca9685_pwm_enable(struct pwm_chip chip, struct pwm_device pwm)
	348	{
	349	struct pca9685 *pca = to_pca(chip);
	350	unsigned int reg;
	351
	352	/*
	353	* The PWM subsystem does not support a pre-delay.
	354	* So, set the ON-timeout to 0
	355	*/
	356	if (pwm->hwpwm >= PCA9685_MAXCHAN)
	357	reg = PCA9685_ALL_LED_ON_L;
	358	else
	359	reg = LED_N_ON_L(pwm->hwpwm);
	360
	361	regmap_write(pca->regmap, reg, 0);
	362
	363	if (pwm->hwpwm >= PCA9685_MAXCHAN)
	364	reg = PCA9685_ALL_LED_ON_H;
	365	else
	366	reg = LED_N_ON_H(pwm->hwpwm);
	367
	368	regmap_write(pca->regmap, reg, 0);
	369
	370	/*
	371	* Clear the full-off bit.
	372	* It has precedence over the others and must be off.
	373	*/
	374	if (pwm->hwpwm >= PCA9685_MAXCHAN)
	375	reg = PCA9685_ALL_LED_OFF_H;
	376	else
	377	reg = LED_N_OFF_H(pwm->hwpwm);
	378
	379	regmap_update_bits(pca->regmap, reg, LED_FULL, 0x0);
	380
	381	return 0;
	382	}
	383
	384	static void pca9685_pwm_disable(struct pwm_chip chip, struct pwm_device pwm)
	385	{
	386	struct pca9685 *pca = to_pca(chip);
	387	unsigned int reg;
	388
	389	if (pwm->hwpwm >= PCA9685_MAXCHAN)
	390	reg = PCA9685_ALL_LED_OFF_H;
	391	else
	392	reg = LED_N_OFF_H(pwm->hwpwm);
	393
	394	regmap_write(pca->regmap, reg, LED_FULL);
	395
	396	/* Clear the LED_OFF counter. */
	397	if (pwm->hwpwm >= PCA9685_MAXCHAN)
	398	reg = PCA9685_ALL_LED_OFF_L;
	399	else
	400	reg = LED_N_OFF_L(pwm->hwpwm);
	401
	402	regmap_write(pca->regmap, reg, 0x0);
	403	}
	404
	405	static int pca9685_pwm_request(struct pwm_chip chip, struct pwm_device pwm)
	406	{
	407	struct pca9685 *pca = to_pca(chip);
408
bccec89f MW	409	if (pca9685_pwm_is_gpio(pca, pwm))
bccec89f MW	410	return -EBUSY;
c40c461e	411	pm_runtime_get_sync(chip->dev);
88b613e6 ST	412
	413	return 0;
	414	}
	415
	416	static void pca9685_pwm_free(struct pwm_chip chip, struct pwm_device pwm)
	417	{
c40c461e SVA	418	pca9685_pwm_disable(chip, pwm);
c40c461e SVA	419	pm_runtime_put(chip->dev);
88b613e6 ST	420	}
	421
	422	static const struct pwm_ops pca9685_pwm_ops = {
	423	.enable = pca9685_pwm_enable,
	424	.disable = pca9685_pwm_disable,
	425	.config = pca9685_pwm_config,
	426	.request = pca9685_pwm_request,
	427	.free = pca9685_pwm_free,
3dd0a909	428	.owner = THIS_MODULE,
88b613e6 ST	429	};
88b613e6 ST	430
c456fbb2	431	static const struct regmap_config pca9685_regmap_i2c_config = {
88b613e6 ST	432	.reg_bits = 8,
	433	.val_bits = 8,
	434	.max_register = PCA9685_NUMREGS,
	435	.cache_type = REGCACHE_NONE,
	436	};
	437
	438	static int pca9685_pwm_probe(struct i2c_client *client,
	439	const struct i2c_device_id *id)
	440	{
88b613e6 ST	441	struct pca9685 *pca;
	442	int ret;
	443	int mode2;
	444
	445	pca = devm_kzalloc(&client->dev, sizeof(*pca), GFP_KERNEL);
	446	if (!pca)
	447	return -ENOMEM;
	448
	449	pca->regmap = devm_regmap_init_i2c(client, &pca9685_regmap_i2c_config);
	450	if (IS_ERR(pca->regmap)) {
	451	ret = PTR_ERR(pca->regmap);
	452	dev_err(&client->dev, "Failed to initialize register map: %d\n",
	453	ret);
	454	return ret;
	455	}
01ec8472 CG	456	pca->duty_ns = 0;
01ec8472 CG	457	pca->period_ns = PCA9685_DEFAULT_PERIOD;
88b613e6 ST	458
	459	i2c_set_clientdata(client, pca);
	460
	461	regmap_read(pca->regmap, PCA9685_MODE2, &mode2);
	462
912b8439	463	if (device_property_read_bool(&client->dev, "invert"))
88b613e6 ST	464	mode2 \|= MODE2_INVRT;
	465	else
	466	mode2 &= ~MODE2_INVRT;
	467
912b8439	468	if (device_property_read_bool(&client->dev, "open-drain"))
88b613e6 ST	469	mode2 &= ~MODE2_OUTDRV;
	470	else
	471	mode2 \|= MODE2_OUTDRV;
	472
	473	regmap_write(pca->regmap, PCA9685_MODE2, mode2);
	474
	475	/* clear all "full off" bits */
	476	regmap_write(pca->regmap, PCA9685_ALL_LED_OFF_L, 0);
	477	regmap_write(pca->regmap, PCA9685_ALL_LED_OFF_H, 0);
	478
	479	pca->chip.ops = &pca9685_pwm_ops;
	480	/* add an extra channel for ALL_LED */
	481	pca->chip.npwm = PCA9685_MAXCHAN + 1;
	482
	483	pca->chip.dev = &client->dev;
	484	pca->chip.base = -1;
88b613e6	485
bccec89f MW	486	ret = pwmchip_add(&pca->chip);
	487	if (ret < 0)
	488	return ret;
	489
	490	ret = pca9685_pwm_gpio_probe(pca);
c40c461e	491	if (ret < 0) {
bccec89f	492	pwmchip_remove(&pca->chip);
c40c461e SVA	493	return ret;
	494	}
	495
	496	/* the chip comes out of power-up in the active state */
	497	pm_runtime_set_active(&client->dev);
	498	/*
	499	* enable will put the chip into suspend, which is what we
	500	* want as all outputs are disabled at this point
	501	*/
	502	pm_runtime_enable(&client->dev);
bccec89f	503
c40c461e	504	return 0;
88b613e6 ST	505	}
	506
	507	static int pca9685_pwm_remove(struct i2c_client *client)
	508	{
	509	struct pca9685 *pca = i2c_get_clientdata(client);
c40c461e	510	int ret;
88b613e6	511
c40c461e SVA	512	ret = pwmchip_remove(&pca->chip);
	513	if (ret)
	514	return ret;
	515	pm_runtime_disable(&client->dev);
	516	return 0;
	517	}
88b613e6	518
c40c461e SVA	519	#ifdef CONFIG_PM
	520	static int pca9685_pwm_runtime_suspend(struct device *dev)
	521	{
	522	struct i2c_client *client = to_i2c_client(dev);
	523	struct pca9685 *pca = i2c_get_clientdata(client);
	524
0829326a	525	pca9685_set_sleep_mode(pca, true);
c40c461e	526	return 0;
88b613e6 ST	527	}
88b613e6 ST	528
c40c461e SVA	529	static int pca9685_pwm_runtime_resume(struct device *dev)
	530	{
	531	struct i2c_client *client = to_i2c_client(dev);
	532	struct pca9685 *pca = i2c_get_clientdata(client);
	533
0829326a	534	pca9685_set_sleep_mode(pca, false);
c40c461e SVA	535	return 0;
	536	}
	537	#endif
	538
88b613e6 ST	539	static const struct i2c_device_id pca9685_id[] = {
	540	{ "pca9685", 0 },
	541	{ /* sentinel */ },
	542	};
	543	MODULE_DEVICE_TABLE(i2c, pca9685_id);
	544
912b8439 AS	545	#ifdef CONFIG_ACPI
	546	static const struct acpi_device_id pca9685_acpi_ids[] = {
	547	{ "INT3492", 0 },
	548	{ /* sentinel */ },
	549	};
	550	MODULE_DEVICE_TABLE(acpi, pca9685_acpi_ids);
	551	#endif
	552
	553	#ifdef CONFIG_OF
88b613e6 ST	554	static const struct of_device_id pca9685_dt_ids[] = {
	555	{ .compatible = "nxp,pca9685-pwm", },
	556	{ /* sentinel */ }
	557	};
	558	MODULE_DEVICE_TABLE(of, pca9685_dt_ids);
912b8439	559	#endif
88b613e6	560
c40c461e SVA	561	static const struct dev_pm_ops pca9685_pwm_pm = {
	562	SET_RUNTIME_PM_OPS(pca9685_pwm_runtime_suspend,
	563	pca9685_pwm_runtime_resume, NULL)
	564	};
	565
88b613e6 ST	566	static struct i2c_driver pca9685_i2c_driver = {
	567	.driver = {
	568	.name = "pca9685-pwm",
912b8439 AS	569	.acpi_match_table = ACPI_PTR(pca9685_acpi_ids),
912b8439 AS	570	.of_match_table = of_match_ptr(pca9685_dt_ids),
c40c461e	571	.pm = &pca9685_pwm_pm,
88b613e6 ST	572	},
	573	.probe = pca9685_pwm_probe,
	574	.remove = pca9685_pwm_remove,
	575	.id_table = pca9685_id,
	576	};
	577
	578	module_i2c_driver(pca9685_i2c_driver);
	579
	580	MODULE_AUTHOR("Steffen Trumtrar <s.trumtrar@pengutronix.de>");
	581	MODULE_DESCRIPTION("PWM driver for PCA9685");
	582	MODULE_LICENSE("GPL");