Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 600 insertions, 0 deletions

diff --git a/drivers/pwm/pwm-pca9685.c b/drivers/pwm/pwm-pca9685.c
new file mode 100644
index 000000000..259fd5881
--- /dev/null
+++ b/drivers/pwm/pwm-pca9685.c
@@ -0,0 +1,600 @@
+/*
+ * 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>
+#include <linux/bitmap.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;
+	DECLARE_BITMAP(pwms_inuse, PCA9685_MAXCHAN + 1);
+#endif
+};
+
+static inline struct pca9685 *to_pca(struct pwm_chip *chip)
+{
+	return container_of(chip, struct pca9685, chip);
+}
+
+#if IS_ENABLED(CONFIG_GPIOLIB)
+static bool pca9685_pwm_test_and_set_inuse(struct pca9685 *pca, int pwm_idx)
+{
+	bool is_inuse;
+
+	mutex_lock(&pca->lock);
+	if (pwm_idx >= PCA9685_MAXCHAN) {
+		/*
+		 * "all LEDs" channel:
+		 * pretend already in use if any of the PWMs are requested
+		 */
+		if (!bitmap_empty(pca->pwms_inuse, PCA9685_MAXCHAN)) {
+			is_inuse = true;
+			goto out;
+		}
+	} else {
+		/*
+		 * regular channel:
+		 * pretend already in use if the "all LEDs" channel is requested
+		 */
+		if (test_bit(PCA9685_MAXCHAN, pca->pwms_inuse)) {
+			is_inuse = true;
+			goto out;
+		}
+	}
+	is_inuse = test_and_set_bit(pwm_idx, pca->pwms_inuse);
+out:
+	mutex_unlock(&pca->lock);
+	return is_inuse;
+}
+
+static void pca9685_pwm_clear_inuse(struct pca9685 *pca, int pwm_idx)
+{
+	mutex_lock(&pca->lock);
+	clear_bit(pwm_idx, pca->pwms_inuse);
+	mutex_unlock(&pca->lock);
+}
+
+static int pca9685_pwm_gpio_request(struct gpio_chip *gpio, unsigned int offset)
+{
+	struct pca9685 *pca = gpiochip_get_data(gpio);
+
+	if (pca9685_pwm_test_and_set_inuse(pca, offset))
+		return -EBUSY;
+	pm_runtime_get_sync(pca->chip.dev);
+	return 0;
+}
+
+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);
+
+	pca9685_pwm_gpio_set(gpio, offset, 0);
+	pm_runtime_put(pca->chip.dev);
+	pca9685_pwm_clear_inuse(pca, offset);
+}
+
+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_test_and_set_inuse(struct pca9685 *pca,
+						  int pwm_idx)
+{
+	return false;
+}
+
+static inline void
+pca9685_pwm_clear_inuse(struct pca9685 *pca, int pwm_idx)
+{
+}
+
+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_test_and_set_inuse(pca, pwm->hwpwm))
+		return -EBUSY;
+	pm_runtime_get_sync(chip->dev);
+
+	return 0;
+}
+
+static void pca9685_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct pca9685 *pca = to_pca(chip);
+
+	pca9685_pwm_disable(chip, pwm);
+	pm_runtime_put(chip->dev);
+	pca9685_pwm_clear_inuse(pca, pwm->hwpwm);
+}
+
+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");