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

/*
 * 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
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published by
 * the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#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];
	pwm_set_chip_data(pwm, NULL);
	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
88b613e6 ST	1	/*
	2	* Driver for PCA9685 16-channel 12-bit PWM LED controller
	3	*
	4	* Copyright (C) 2013 Steffen Trumtrar <s.trumtrar@pengutronix.de>
01ec8472	5	* Copyright (C) 2015 Clemens Gruber <clemens.gruber@pqgruber.com>
88b613e6 ST	6	*
	7	* based on the pwm-twl-led.c driver
	8	*
	9	* This program is free software; you can redistribute it and/or modify it
	10	* under the terms of the GNU General Public License version 2 as published by
	11	* the Free Software Foundation.
	12	*
	13	* This program is distributed in the hope that it will be useful, but WITHOUT
	14	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	15	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	16	* more details.
	17	*
	18	* You should have received a copy of the GNU General Public License along with
	19	* this program. If not, see <http://www.gnu.org/licenses/>.
	20	*/
	21
912b8439	22	#include <linux/acpi.h>
bccec89f	23	#include <linux/gpio/driver.h>
88b613e6 ST	24	#include <linux/i2c.h>
88b613e6 ST	25	#include <linux/module.h>
bccec89f	26	#include <linux/mutex.h>
88b613e6	27	#include <linux/platform_device.h>
912b8439	28	#include <linux/property.h>
88b613e6 ST	29	#include <linux/pwm.h>
	30	#include <linux/regmap.h>
	31	#include <linux/slab.h>
01ec8472	32	#include <linux/delay.h>
c40c461e	33	#include <linux/pm_runtime.h>
01ec8472 CG	34
	35	/*
	36	* Because the PCA9685 has only one prescaler per chip, changing the period of
	37	* one channel affects the period of all 16 PWM outputs!
	38	* However, the ratio between each configured duty cycle and the chip-wide
	39	* period remains constant, because the OFF time is set in proportion to the
	40	* counter range.
	41	*/
88b613e6 ST	42
	43	#define PCA9685_MODE1 0x00
	44	#define PCA9685_MODE2 0x01
	45	#define PCA9685_SUBADDR1 0x02
	46	#define PCA9685_SUBADDR2 0x03
	47	#define PCA9685_SUBADDR3 0x04
	48	#define PCA9685_ALLCALLADDR 0x05
	49	#define PCA9685_LEDX_ON_L 0x06
	50	#define PCA9685_LEDX_ON_H 0x07
	51	#define PCA9685_LEDX_OFF_L 0x08
	52	#define PCA9685_LEDX_OFF_H 0x09
	53
	54	#define PCA9685_ALL_LED_ON_L 0xFA
	55	#define PCA9685_ALL_LED_ON_H 0xFB
	56	#define PCA9685_ALL_LED_OFF_L 0xFC
	57	#define PCA9685_ALL_LED_OFF_H 0xFD
	58	#define PCA9685_PRESCALE 0xFE
	59
01ec8472 CG	60	#define PCA9685_PRESCALE_MIN 0x03 /* => max. frequency of 1526 Hz */
	61	#define PCA9685_PRESCALE_MAX 0xFF /* => min. frequency of 24 Hz */
	62
	63	#define PCA9685_COUNTER_RANGE 4096
	64	#define PCA9685_DEFAULT_PERIOD 5000000 /* Default period_ns = 1/200 Hz */
	65	#define PCA9685_OSC_CLOCK_MHZ 25 /* Internal oscillator with 25 MHz */
	66
88b613e6 ST	67	#define PCA9685_NUMREGS 0xFF
	68	#define PCA9685_MAXCHAN 0x10
	69
	70	#define LED_FULL (1 << 4)
	71	#define MODE1_SLEEP (1 << 4)
	72	#define MODE2_INVRT (1 << 4)
	73	#define MODE2_OUTDRV (1 << 2)
	74
	75	#define LED_N_ON_H(N) (PCA9685_LEDX_ON_H + (4 * (N)))
	76	#define LED_N_ON_L(N) (PCA9685_LEDX_ON_L + (4 * (N)))
	77	#define LED_N_OFF_H(N) (PCA9685_LEDX_OFF_H + (4 * (N)))
	78	#define LED_N_OFF_L(N) (PCA9685_LEDX_OFF_L + (4 * (N)))
	79
	80	struct pca9685 {
	81	struct pwm_chip chip;
	82	struct regmap *regmap;
01ec8472 CG	83	int duty_ns;
01ec8472 CG	84	int period_ns;
bccec89f MW	85	#if IS_ENABLED(CONFIG_GPIOLIB)
	86	struct mutex lock;
	87	struct gpio_chip gpio;
	88	#endif
88b613e6 ST	89	};
	90
	91	static inline struct pca9685 to_pca(struct pwm_chip chip)
	92	{
	93	return container_of(chip, struct pca9685, chip);
	94	}
	95
bccec89f MW	96	#if IS_ENABLED(CONFIG_GPIOLIB)
	97	static int pca9685_pwm_gpio_request(struct gpio_chip *gpio, unsigned int offset)
	98	{
	99	struct pca9685 *pca = gpiochip_get_data(gpio);
	100	struct pwm_device *pwm;
	101
	102	mutex_lock(&pca->lock);
	103
	104	pwm = &pca->chip.pwms[offset];
	105
	106	if (pwm->flags & (PWMF_REQUESTED \| PWMF_EXPORTED)) {
	107	mutex_unlock(&pca->lock);
	108	return -EBUSY;
	109	}
	110
	111	pwm_set_chip_data(pwm, (void *)1);
	112
	113	mutex_unlock(&pca->lock);
c40c461e	114	pm_runtime_get_sync(pca->chip.dev);
bccec89f MW	115	return 0;
	116	}
	117
bccec89f MW	118	static bool pca9685_pwm_is_gpio(struct pca9685 pca, struct pwm_device pwm)
	119	{
	120	bool is_gpio = false;
	121
	122	mutex_lock(&pca->lock);
	123
	124	if (pwm->hwpwm >= PCA9685_MAXCHAN) {
	125	unsigned int i;
	126
	127	/*
	128	* Check if any of the GPIOs are requested and in that case
	129	* prevent using the "all LEDs" channel.
	130	*/
	131	for (i = 0; i < pca->gpio.ngpio; i++)
	132	if (gpiochip_is_requested(&pca->gpio, i)) {
	133	is_gpio = true;
	134	break;
	135	}
	136	} else if (pwm_get_chip_data(pwm)) {
	137	is_gpio = true;
	138	}
	139
	140	mutex_unlock(&pca->lock);
	141	return is_gpio;
	142	}
	143
	144	static int pca9685_pwm_gpio_get(struct gpio_chip *gpio, unsigned int offset)
	145	{
	146	struct pca9685 *pca = gpiochip_get_data(gpio);
	147	struct pwm_device *pwm = &pca->chip.pwms[offset];
	148	unsigned int value;
	149
	150	regmap_read(pca->regmap, LED_N_ON_H(pwm->hwpwm), &value);
	151
	152	return value & LED_FULL;
	153	}
	154
	155	static void pca9685_pwm_gpio_set(struct gpio_chip *gpio, unsigned int offset,
	156	int value)
	157	{
	158	struct pca9685 *pca = gpiochip_get_data(gpio);
	159	struct pwm_device *pwm = &pca->chip.pwms[offset];
	160	unsigned int on = value ? LED_FULL : 0;
	161
	162	/* Clear both OFF registers */
	163	regmap_write(pca->regmap, LED_N_OFF_L(pwm->hwpwm), 0);
	164	regmap_write(pca->regmap, LED_N_OFF_H(pwm->hwpwm), 0);
	165
	166	/* Set the full ON bit */
	167	regmap_write(pca->regmap, LED_N_ON_H(pwm->hwpwm), on);
	168	}
	169
c40c461e SVA	170	static void pca9685_pwm_gpio_free(struct gpio_chip *gpio, unsigned int offset)
	171	{
	172	struct pca9685 *pca = gpiochip_get_data(gpio);
	173	struct pwm_device *pwm;
	174
	175	pca9685_pwm_gpio_set(gpio, offset, 0);
	176	pm_runtime_put(pca->chip.dev);
	177	mutex_lock(&pca->lock);
	178	pwm = &pca->chip.pwms[offset];
	179	pwm_set_chip_data(pwm, NULL);
	180	mutex_unlock(&pca->lock);
	181	}
	182
bccec89f MW	183	static int pca9685_pwm_gpio_get_direction(struct gpio_chip *chip,
	184	unsigned int offset)
	185	{
	186	/* Always out */
	187	return 0;
	188	}
	189
	190	static int pca9685_pwm_gpio_direction_input(struct gpio_chip *gpio,
	191	unsigned int offset)
	192	{
	193	return -EINVAL;
	194	}
	195
	196	static int pca9685_pwm_gpio_direction_output(struct gpio_chip *gpio,
	197	unsigned int offset, int value)
	198	{
	199	pca9685_pwm_gpio_set(gpio, offset, value);
	200
	201	return 0;
	202	}
	203
	204	/*
	205	* The PCA9685 has a bit for turning the PWM output full off or on. Some
	206	* boards like Intel Galileo actually uses these as normal GPIOs so we
	207	* expose a GPIO chip here which can exclusively take over the underlying
	208	* PWM channel.
	209	*/
	210	static int pca9685_pwm_gpio_probe(struct pca9685 *pca)
	211	{
	212	struct device *dev = pca->chip.dev;
	213
	214	mutex_init(&pca->lock);
	215
	216	pca->gpio.label = dev_name(dev);
	217	pca->gpio.parent = dev;
	218	pca->gpio.request = pca9685_pwm_gpio_request;
	219	pca->gpio.free = pca9685_pwm_gpio_free;
	220	pca->gpio.get_direction = pca9685_pwm_gpio_get_direction;
	221	pca->gpio.direction_input = pca9685_pwm_gpio_direction_input;
	222	pca->gpio.direction_output = pca9685_pwm_gpio_direction_output;
	223	pca->gpio.get = pca9685_pwm_gpio_get;
	224	pca->gpio.set = pca9685_pwm_gpio_set;
	225	pca->gpio.base = -1;
	226	pca->gpio.ngpio = PCA9685_MAXCHAN;
	227	pca->gpio.can_sleep = true;
	228
	229	return devm_gpiochip_add_data(dev, &pca->gpio, pca);
	230	}
	231	#else
	232	static inline bool pca9685_pwm_is_gpio(struct pca9685 *pca,
	233	struct pwm_device *pwm)
	234	{
	235	return false;
	236	}
	237
	238	static inline int pca9685_pwm_gpio_probe(struct pca9685 *pca)
	239	{
	240	return 0;
	241	}
	242	#endif
	243
0829326a	244	static void pca9685_set_sleep_mode(struct pca9685 *pca, bool enable)
c40c461e SVA	245	{
c40c461e SVA	246	regmap_update_bits(pca->regmap, PCA9685_MODE1,
0829326a SVA	247	MODE1_SLEEP, enable ? MODE1_SLEEP : 0);
0829326a SVA	248	if (!enable) {
c40c461e SVA	249	/* Wait 500us for the oscillator to be back up */
	250	udelay(500);
	251	}
	252	}
	253
88b613e6 ST	254	static int pca9685_pwm_config(struct pwm_chip chip, struct pwm_device pwm,
	255	int duty_ns, int period_ns)
	256	{
	257	struct pca9685 *pca = to_pca(chip);
	258	unsigned long long duty;
	259	unsigned int reg;
01ec8472 CG	260	int prescale;
	261
	262	if (period_ns != pca->period_ns) {
	263	prescale = DIV_ROUND_CLOSEST(PCA9685_OSC_CLOCK_MHZ * period_ns,
	264	PCA9685_COUNTER_RANGE * 1000) - 1;
	265
	266	if (prescale >= PCA9685_PRESCALE_MIN &&
	267	prescale <= PCA9685_PRESCALE_MAX) {
c40c461e SVA	268	/*
	269	* putting the chip briefly into SLEEP mode
	270	* at this point won't interfere with the
	271	* pm_runtime framework, because the pm_runtime
	272	* state is guaranteed active here.
	273	*/
01ec8472	274	/* Put chip into sleep mode */
0829326a	275	pca9685_set_sleep_mode(pca, true);
01ec8472 CG	276
	277	/* Change the chip-wide output frequency */
	278	regmap_write(pca->regmap, PCA9685_PRESCALE, prescale);
	279
	280	/* Wake the chip up */
0829326a	281	pca9685_set_sleep_mode(pca, false);
01ec8472 CG	282
01ec8472 CG	283	pca->period_ns = period_ns;
01ec8472 CG	284	} else {
	285	dev_err(chip->dev,
	286	"prescaler not set: period out of bounds!\n");
	287	return -EINVAL;
	288	}
	289	}
	290
	291	pca->duty_ns = duty_ns;
88b613e6 ST	292
	293	if (duty_ns < 1) {
	294	if (pwm->hwpwm >= PCA9685_MAXCHAN)
	295	reg = PCA9685_ALL_LED_OFF_H;
	296	else
	297	reg = LED_N_OFF_H(pwm->hwpwm);
	298
	299	regmap_write(pca->regmap, reg, LED_FULL);
	300
	301	return 0;
	302	}
	303
	304	if (duty_ns == period_ns) {
4a627b52 CG	305	/* Clear both OFF registers */
	306	if (pwm->hwpwm >= PCA9685_MAXCHAN)
	307	reg = PCA9685_ALL_LED_OFF_L;
	308	else
	309	reg = LED_N_OFF_L(pwm->hwpwm);
	310
	311	regmap_write(pca->regmap, reg, 0x0);
	312
	313	if (pwm->hwpwm >= PCA9685_MAXCHAN)
	314	reg = PCA9685_ALL_LED_OFF_H;
	315	else
	316	reg = LED_N_OFF_H(pwm->hwpwm);
	317
	318	regmap_write(pca->regmap, reg, 0x0);
	319
	320	/* Set the full ON bit */
88b613e6 ST	321	if (pwm->hwpwm >= PCA9685_MAXCHAN)
	322	reg = PCA9685_ALL_LED_ON_H;
	323	else
	324	reg = LED_N_ON_H(pwm->hwpwm);
	325
	326	regmap_write(pca->regmap, reg, LED_FULL);
	327
	328	return 0;
	329	}
	330
01ec8472	331	duty = PCA9685_COUNTER_RANGE * (unsigned long long)duty_ns;
88b613e6 ST	332	duty = DIV_ROUND_UP_ULL(duty, period_ns);
	333
	334	if (pwm->hwpwm >= PCA9685_MAXCHAN)
	335	reg = PCA9685_ALL_LED_OFF_L;
	336	else
	337	reg = LED_N_OFF_L(pwm->hwpwm);
	338
	339	regmap_write(pca->regmap, reg, (int)duty & 0xff);
	340
	341	if (pwm->hwpwm >= PCA9685_MAXCHAN)
	342	reg = PCA9685_ALL_LED_OFF_H;
	343	else
	344	reg = LED_N_OFF_H(pwm->hwpwm);
	345
	346	regmap_write(pca->regmap, reg, ((int)duty >> 8) & 0xf);
	347
4a627b52 CG	348	/* Clear the full ON bit, otherwise the set OFF time has no effect */
	349	if (pwm->hwpwm >= PCA9685_MAXCHAN)
	350	reg = PCA9685_ALL_LED_ON_H;
	351	else
	352	reg = LED_N_ON_H(pwm->hwpwm);
	353
	354	regmap_write(pca->regmap, reg, 0);
	355
88b613e6 ST	356	return 0;
	357	}
	358
	359	static int pca9685_pwm_enable(struct pwm_chip chip, struct pwm_device pwm)
	360	{
	361	struct pca9685 *pca = to_pca(chip);
	362	unsigned int reg;
	363
	364	/*
	365	* The PWM subsystem does not support a pre-delay.
	366	* So, set the ON-timeout to 0
	367	*/
	368	if (pwm->hwpwm >= PCA9685_MAXCHAN)
	369	reg = PCA9685_ALL_LED_ON_L;
	370	else
	371	reg = LED_N_ON_L(pwm->hwpwm);
	372
	373	regmap_write(pca->regmap, reg, 0);
	374
	375	if (pwm->hwpwm >= PCA9685_MAXCHAN)
	376	reg = PCA9685_ALL_LED_ON_H;
	377	else
	378	reg = LED_N_ON_H(pwm->hwpwm);
	379
	380	regmap_write(pca->regmap, reg, 0);
	381
	382	/*
	383	* Clear the full-off bit.
	384	* It has precedence over the others and must be off.
	385	*/
	386	if (pwm->hwpwm >= PCA9685_MAXCHAN)
	387	reg = PCA9685_ALL_LED_OFF_H;
	388	else
	389	reg = LED_N_OFF_H(pwm->hwpwm);
	390
	391	regmap_update_bits(pca->regmap, reg, LED_FULL, 0x0);
	392
	393	return 0;
	394	}
	395
	396	static void pca9685_pwm_disable(struct pwm_chip chip, struct pwm_device pwm)
	397	{
	398	struct pca9685 *pca = to_pca(chip);
	399	unsigned int reg;
	400
	401	if (pwm->hwpwm >= PCA9685_MAXCHAN)
	402	reg = PCA9685_ALL_LED_OFF_H;
	403	else
	404	reg = LED_N_OFF_H(pwm->hwpwm);
	405
	406	regmap_write(pca->regmap, reg, LED_FULL);
	407
	408	/* Clear the LED_OFF counter. */
	409	if (pwm->hwpwm >= PCA9685_MAXCHAN)
	410	reg = PCA9685_ALL_LED_OFF_L;
	411	else
	412	reg = LED_N_OFF_L(pwm->hwpwm);
	413
	414	regmap_write(pca->regmap, reg, 0x0);
	415	}
	416
	417	static int pca9685_pwm_request(struct pwm_chip chip, struct pwm_device pwm)
	418	{
	419	struct pca9685 *pca = to_pca(chip);
420
bccec89f MW	421	if (pca9685_pwm_is_gpio(pca, pwm))
bccec89f MW	422	return -EBUSY;
c40c461e	423	pm_runtime_get_sync(chip->dev);
88b613e6 ST	424
	425	return 0;
	426	}
	427
	428	static void pca9685_pwm_free(struct pwm_chip chip, struct pwm_device pwm)
	429	{
c40c461e SVA	430	pca9685_pwm_disable(chip, pwm);
c40c461e SVA	431	pm_runtime_put(chip->dev);
88b613e6 ST	432	}
	433
	434	static const struct pwm_ops pca9685_pwm_ops = {
	435	.enable = pca9685_pwm_enable,
	436	.disable = pca9685_pwm_disable,
	437	.config = pca9685_pwm_config,
	438	.request = pca9685_pwm_request,
	439	.free = pca9685_pwm_free,
3dd0a909	440	.owner = THIS_MODULE,
88b613e6 ST	441	};
88b613e6 ST	442
c456fbb2	443	static const struct regmap_config pca9685_regmap_i2c_config = {
88b613e6 ST	444	.reg_bits = 8,
	445	.val_bits = 8,
	446	.max_register = PCA9685_NUMREGS,
	447	.cache_type = REGCACHE_NONE,
	448	};
	449
	450	static int pca9685_pwm_probe(struct i2c_client *client,
	451	const struct i2c_device_id *id)
	452	{
88b613e6 ST	453	struct pca9685 *pca;
	454	int ret;
	455	int mode2;
	456
	457	pca = devm_kzalloc(&client->dev, sizeof(*pca), GFP_KERNEL);
	458	if (!pca)
	459	return -ENOMEM;
	460
	461	pca->regmap = devm_regmap_init_i2c(client, &pca9685_regmap_i2c_config);
	462	if (IS_ERR(pca->regmap)) {
	463	ret = PTR_ERR(pca->regmap);
	464	dev_err(&client->dev, "Failed to initialize register map: %d\n",
	465	ret);
	466	return ret;
	467	}
01ec8472 CG	468	pca->duty_ns = 0;
01ec8472 CG	469	pca->period_ns = PCA9685_DEFAULT_PERIOD;
88b613e6 ST	470
	471	i2c_set_clientdata(client, pca);
	472
	473	regmap_read(pca->regmap, PCA9685_MODE2, &mode2);
	474
912b8439	475	if (device_property_read_bool(&client->dev, "invert"))
88b613e6 ST	476	mode2 \|= MODE2_INVRT;
	477	else
	478	mode2 &= ~MODE2_INVRT;
	479
912b8439	480	if (device_property_read_bool(&client->dev, "open-drain"))
88b613e6 ST	481	mode2 &= ~MODE2_OUTDRV;
	482	else
	483	mode2 \|= MODE2_OUTDRV;
	484
	485	regmap_write(pca->regmap, PCA9685_MODE2, mode2);
	486
	487	/* clear all "full off" bits */
	488	regmap_write(pca->regmap, PCA9685_ALL_LED_OFF_L, 0);
	489	regmap_write(pca->regmap, PCA9685_ALL_LED_OFF_H, 0);
	490
	491	pca->chip.ops = &pca9685_pwm_ops;
	492	/* add an extra channel for ALL_LED */
	493	pca->chip.npwm = PCA9685_MAXCHAN + 1;
	494
	495	pca->chip.dev = &client->dev;
	496	pca->chip.base = -1;
88b613e6	497
bccec89f MW	498	ret = pwmchip_add(&pca->chip);
	499	if (ret < 0)
	500	return ret;
	501
	502	ret = pca9685_pwm_gpio_probe(pca);
c40c461e	503	if (ret < 0) {
bccec89f	504	pwmchip_remove(&pca->chip);
c40c461e SVA	505	return ret;
	506	}
	507
	508	/* the chip comes out of power-up in the active state */
	509	pm_runtime_set_active(&client->dev);
	510	/*
	511	* enable will put the chip into suspend, which is what we
	512	* want as all outputs are disabled at this point
	513	*/
	514	pm_runtime_enable(&client->dev);
bccec89f	515
c40c461e	516	return 0;
88b613e6 ST	517	}
	518
	519	static int pca9685_pwm_remove(struct i2c_client *client)
	520	{
	521	struct pca9685 *pca = i2c_get_clientdata(client);
c40c461e	522	int ret;
88b613e6	523
c40c461e SVA	524	ret = pwmchip_remove(&pca->chip);
	525	if (ret)
	526	return ret;
	527	pm_runtime_disable(&client->dev);
	528	return 0;
	529	}
88b613e6	530
c40c461e SVA	531	#ifdef CONFIG_PM
	532	static int pca9685_pwm_runtime_suspend(struct device *dev)
	533	{
	534	struct i2c_client *client = to_i2c_client(dev);
	535	struct pca9685 *pca = i2c_get_clientdata(client);
	536
0829326a	537	pca9685_set_sleep_mode(pca, true);
c40c461e	538	return 0;
88b613e6 ST	539	}
88b613e6 ST	540
c40c461e SVA	541	static int pca9685_pwm_runtime_resume(struct device *dev)
	542	{
	543	struct i2c_client *client = to_i2c_client(dev);
	544	struct pca9685 *pca = i2c_get_clientdata(client);
	545
0829326a	546	pca9685_set_sleep_mode(pca, false);
c40c461e SVA	547	return 0;
	548	}
	549	#endif
	550
88b613e6 ST	551	static const struct i2c_device_id pca9685_id[] = {
	552	{ "pca9685", 0 },
	553	{ /* sentinel */ },
	554	};
	555	MODULE_DEVICE_TABLE(i2c, pca9685_id);
	556
912b8439 AS	557	#ifdef CONFIG_ACPI
	558	static const struct acpi_device_id pca9685_acpi_ids[] = {
	559	{ "INT3492", 0 },
	560	{ /* sentinel */ },
	561	};
	562	MODULE_DEVICE_TABLE(acpi, pca9685_acpi_ids);
	563	#endif
	564
	565	#ifdef CONFIG_OF
88b613e6 ST	566	static const struct of_device_id pca9685_dt_ids[] = {
	567	{ .compatible = "nxp,pca9685-pwm", },
	568	{ /* sentinel */ }
	569	};
	570	MODULE_DEVICE_TABLE(of, pca9685_dt_ids);
912b8439	571	#endif
88b613e6	572
c40c461e SVA	573	static const struct dev_pm_ops pca9685_pwm_pm = {
	574	SET_RUNTIME_PM_OPS(pca9685_pwm_runtime_suspend,
	575	pca9685_pwm_runtime_resume, NULL)
	576	};
	577
88b613e6 ST	578	static struct i2c_driver pca9685_i2c_driver = {
	579	.driver = {
	580	.name = "pca9685-pwm",
912b8439 AS	581	.acpi_match_table = ACPI_PTR(pca9685_acpi_ids),
912b8439 AS	582	.of_match_table = of_match_ptr(pca9685_dt_ids),
c40c461e	583	.pm = &pca9685_pwm_pm,
88b613e6 ST	584	},
	585	.probe = pca9685_pwm_probe,
	586	.remove = pca9685_pwm_remove,
	587	.id_table = pca9685_id,
	588	};
	589
	590	module_i2c_driver(pca9685_i2c_driver);
	591
	592	MODULE_AUTHOR("Steffen Trumtrar <s.trumtrar@pengutronix.de>");
	593	MODULE_DESCRIPTION("PWM driver for PCA9685");
	594	MODULE_LICENSE("GPL");