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1/*
2 * Driver for PCA9685 16-channel 12-bit PWM LED controller
3 *
4 * Copyright (C) 2013 Steffen Trumtrar <s.trumtrar@pengutronix.de>
5 * Copyright (C) 2015 Clemens Gruber <clemens.gruber@pqgruber.com>
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
22#include <linux/acpi.h>
23#include <linux/i2c.h>
24#include <linux/module.h>
25#include <linux/platform_device.h>
26#include <linux/property.h>
27#include <linux/pwm.h>
28#include <linux/regmap.h>
29#include <linux/slab.h>
30#include <linux/delay.h>
31
32/*
33 * Because the PCA9685 has only one prescaler per chip, changing the period of
34 * one channel affects the period of all 16 PWM outputs!
35 * However, the ratio between each configured duty cycle and the chip-wide
36 * period remains constant, because the OFF time is set in proportion to the
37 * counter range.
38 */
39
40#define PCA9685_MODE1 0x00
41#define PCA9685_MODE2 0x01
42#define PCA9685_SUBADDR1 0x02
43#define PCA9685_SUBADDR2 0x03
44#define PCA9685_SUBADDR3 0x04
45#define PCA9685_ALLCALLADDR 0x05
46#define PCA9685_LEDX_ON_L 0x06
47#define PCA9685_LEDX_ON_H 0x07
48#define PCA9685_LEDX_OFF_L 0x08
49#define PCA9685_LEDX_OFF_H 0x09
50
51#define PCA9685_ALL_LED_ON_L 0xFA
52#define PCA9685_ALL_LED_ON_H 0xFB
53#define PCA9685_ALL_LED_OFF_L 0xFC
54#define PCA9685_ALL_LED_OFF_H 0xFD
55#define PCA9685_PRESCALE 0xFE
56
57#define PCA9685_PRESCALE_MIN 0x03 /* => max. frequency of 1526 Hz */
58#define PCA9685_PRESCALE_MAX 0xFF /* => min. frequency of 24 Hz */
59
60#define PCA9685_COUNTER_RANGE 4096
61#define PCA9685_DEFAULT_PERIOD 5000000 /* Default period_ns = 1/200 Hz */
62#define PCA9685_OSC_CLOCK_MHZ 25 /* Internal oscillator with 25 MHz */
63
64#define PCA9685_NUMREGS 0xFF
65#define PCA9685_MAXCHAN 0x10
66
67#define LED_FULL (1 << 4)
68#define MODE1_RESTART (1 << 7)
69#define MODE1_SLEEP (1 << 4)
70#define MODE2_INVRT (1 << 4)
71#define MODE2_OUTDRV (1 << 2)
72
73#define LED_N_ON_H(N) (PCA9685_LEDX_ON_H + (4 * (N)))
74#define LED_N_ON_L(N) (PCA9685_LEDX_ON_L + (4 * (N)))
75#define LED_N_OFF_H(N) (PCA9685_LEDX_OFF_H + (4 * (N)))
76#define LED_N_OFF_L(N) (PCA9685_LEDX_OFF_L + (4 * (N)))
77
78struct pca9685 {
79 struct pwm_chip chip;
80 struct regmap *regmap;
81 int active_cnt;
82 int duty_ns;
83 int period_ns;
84};
85
86static inline struct pca9685 *to_pca(struct pwm_chip *chip)
87{
88 return container_of(chip, struct pca9685, chip);
89}
90
91static int pca9685_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
92 int duty_ns, int period_ns)
93{
94 struct pca9685 *pca = to_pca(chip);
95 unsigned long long duty;
96 unsigned int reg;
97 int prescale;
98
99 if (period_ns != pca->period_ns) {
100 prescale = DIV_ROUND_CLOSEST(PCA9685_OSC_CLOCK_MHZ * period_ns,
101 PCA9685_COUNTER_RANGE * 1000) - 1;
102
103 if (prescale >= PCA9685_PRESCALE_MIN &&
104 prescale <= PCA9685_PRESCALE_MAX) {
105 /* Put chip into sleep mode */
106 regmap_update_bits(pca->regmap, PCA9685_MODE1,
107 MODE1_SLEEP, MODE1_SLEEP);
108
109 /* Change the chip-wide output frequency */
110 regmap_write(pca->regmap, PCA9685_PRESCALE, prescale);
111
112 /* Wake the chip up */
113 regmap_update_bits(pca->regmap, PCA9685_MODE1,
114 MODE1_SLEEP, 0x0);
115
116 /* Wait 500us for the oscillator to be back up */
117 udelay(500);
118
119 pca->period_ns = period_ns;
120
121 /*
122 * If the duty cycle did not change, restart PWM with
123 * the same duty cycle to period ratio and return.
124 */
125 if (duty_ns == pca->duty_ns) {
126 regmap_update_bits(pca->regmap, PCA9685_MODE1,
127 MODE1_RESTART, 0x1);
128 return 0;
129 }
130 } else {
131 dev_err(chip->dev,
132 "prescaler not set: period out of bounds!\n");
133 return -EINVAL;
134 }
135 }
136
137 pca->duty_ns = duty_ns;
138
139 if (duty_ns < 1) {
140 if (pwm->hwpwm >= PCA9685_MAXCHAN)
141 reg = PCA9685_ALL_LED_OFF_H;
142 else
143 reg = LED_N_OFF_H(pwm->hwpwm);
144
145 regmap_write(pca->regmap, reg, LED_FULL);
146
147 return 0;
148 }
149
150 if (duty_ns == period_ns) {
151 /* Clear both OFF registers */
152 if (pwm->hwpwm >= PCA9685_MAXCHAN)
153 reg = PCA9685_ALL_LED_OFF_L;
154 else
155 reg = LED_N_OFF_L(pwm->hwpwm);
156
157 regmap_write(pca->regmap, reg, 0x0);
158
159 if (pwm->hwpwm >= PCA9685_MAXCHAN)
160 reg = PCA9685_ALL_LED_OFF_H;
161 else
162 reg = LED_N_OFF_H(pwm->hwpwm);
163
164 regmap_write(pca->regmap, reg, 0x0);
165
166 /* Set the full ON bit */
167 if (pwm->hwpwm >= PCA9685_MAXCHAN)
168 reg = PCA9685_ALL_LED_ON_H;
169 else
170 reg = LED_N_ON_H(pwm->hwpwm);
171
172 regmap_write(pca->regmap, reg, LED_FULL);
173
174 return 0;
175 }
176
177 duty = PCA9685_COUNTER_RANGE * (unsigned long long)duty_ns;
178 duty = DIV_ROUND_UP_ULL(duty, period_ns);
179
180 if (pwm->hwpwm >= PCA9685_MAXCHAN)
181 reg = PCA9685_ALL_LED_OFF_L;
182 else
183 reg = LED_N_OFF_L(pwm->hwpwm);
184
185 regmap_write(pca->regmap, reg, (int)duty & 0xff);
186
187 if (pwm->hwpwm >= PCA9685_MAXCHAN)
188 reg = PCA9685_ALL_LED_OFF_H;
189 else
190 reg = LED_N_OFF_H(pwm->hwpwm);
191
192 regmap_write(pca->regmap, reg, ((int)duty >> 8) & 0xf);
193
194 /* Clear the full ON bit, otherwise the set OFF time has no effect */
195 if (pwm->hwpwm >= PCA9685_MAXCHAN)
196 reg = PCA9685_ALL_LED_ON_H;
197 else
198 reg = LED_N_ON_H(pwm->hwpwm);
199
200 regmap_write(pca->regmap, reg, 0);
201
202 return 0;
203}
204
205static int pca9685_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
206{
207 struct pca9685 *pca = to_pca(chip);
208 unsigned int reg;
209
210 /*
211 * The PWM subsystem does not support a pre-delay.
212 * So, set the ON-timeout to 0
213 */
214 if (pwm->hwpwm >= PCA9685_MAXCHAN)
215 reg = PCA9685_ALL_LED_ON_L;
216 else
217 reg = LED_N_ON_L(pwm->hwpwm);
218
219 regmap_write(pca->regmap, reg, 0);
220
221 if (pwm->hwpwm >= PCA9685_MAXCHAN)
222 reg = PCA9685_ALL_LED_ON_H;
223 else
224 reg = LED_N_ON_H(pwm->hwpwm);
225
226 regmap_write(pca->regmap, reg, 0);
227
228 /*
229 * Clear the full-off bit.
230 * It has precedence over the others and must be off.
231 */
232 if (pwm->hwpwm >= PCA9685_MAXCHAN)
233 reg = PCA9685_ALL_LED_OFF_H;
234 else
235 reg = LED_N_OFF_H(pwm->hwpwm);
236
237 regmap_update_bits(pca->regmap, reg, LED_FULL, 0x0);
238
239 return 0;
240}
241
242static void pca9685_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
243{
244 struct pca9685 *pca = to_pca(chip);
245 unsigned int reg;
246
247 if (pwm->hwpwm >= PCA9685_MAXCHAN)
248 reg = PCA9685_ALL_LED_OFF_H;
249 else
250 reg = LED_N_OFF_H(pwm->hwpwm);
251
252 regmap_write(pca->regmap, reg, LED_FULL);
253
254 /* Clear the LED_OFF counter. */
255 if (pwm->hwpwm >= PCA9685_MAXCHAN)
256 reg = PCA9685_ALL_LED_OFF_L;
257 else
258 reg = LED_N_OFF_L(pwm->hwpwm);
259
260 regmap_write(pca->regmap, reg, 0x0);
261}
262
263static int pca9685_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
264{
265 struct pca9685 *pca = to_pca(chip);
266
267 if (pca->active_cnt++ == 0)
268 return regmap_update_bits(pca->regmap, PCA9685_MODE1,
269 MODE1_SLEEP, 0x0);
270
271 return 0;
272}
273
274static void pca9685_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
275{
276 struct pca9685 *pca = to_pca(chip);
277
278 if (--pca->active_cnt == 0)
279 regmap_update_bits(pca->regmap, PCA9685_MODE1, MODE1_SLEEP,
280 MODE1_SLEEP);
281}
282
283static const struct pwm_ops pca9685_pwm_ops = {
284 .enable = pca9685_pwm_enable,
285 .disable = pca9685_pwm_disable,
286 .config = pca9685_pwm_config,
287 .request = pca9685_pwm_request,
288 .free = pca9685_pwm_free,
289 .owner = THIS_MODULE,
290};
291
292static const struct regmap_config pca9685_regmap_i2c_config = {
293 .reg_bits = 8,
294 .val_bits = 8,
295 .max_register = PCA9685_NUMREGS,
296 .cache_type = REGCACHE_NONE,
297};
298
299static int pca9685_pwm_probe(struct i2c_client *client,
300 const struct i2c_device_id *id)
301{
302 struct pca9685 *pca;
303 int ret;
304 int mode2;
305
306 pca = devm_kzalloc(&client->dev, sizeof(*pca), GFP_KERNEL);
307 if (!pca)
308 return -ENOMEM;
309
310 pca->regmap = devm_regmap_init_i2c(client, &pca9685_regmap_i2c_config);
311 if (IS_ERR(pca->regmap)) {
312 ret = PTR_ERR(pca->regmap);
313 dev_err(&client->dev, "Failed to initialize register map: %d\n",
314 ret);
315 return ret;
316 }
317 pca->duty_ns = 0;
318 pca->period_ns = PCA9685_DEFAULT_PERIOD;
319
320 i2c_set_clientdata(client, pca);
321
322 regmap_read(pca->regmap, PCA9685_MODE2, &mode2);
323
324 if (device_property_read_bool(&client->dev, "invert"))
325 mode2 |= MODE2_INVRT;
326 else
327 mode2 &= ~MODE2_INVRT;
328
329 if (device_property_read_bool(&client->dev, "open-drain"))
330 mode2 &= ~MODE2_OUTDRV;
331 else
332 mode2 |= MODE2_OUTDRV;
333
334 regmap_write(pca->regmap, PCA9685_MODE2, mode2);
335
336 /* clear all "full off" bits */
337 regmap_write(pca->regmap, PCA9685_ALL_LED_OFF_L, 0);
338 regmap_write(pca->regmap, PCA9685_ALL_LED_OFF_H, 0);
339
340 pca->chip.ops = &pca9685_pwm_ops;
341 /* add an extra channel for ALL_LED */
342 pca->chip.npwm = PCA9685_MAXCHAN + 1;
343
344 pca->chip.dev = &client->dev;
345 pca->chip.base = -1;
346 pca->chip.can_sleep = true;
347
348 return pwmchip_add(&pca->chip);
349}
350
351static int pca9685_pwm_remove(struct i2c_client *client)
352{
353 struct pca9685 *pca = i2c_get_clientdata(client);
354
355 regmap_update_bits(pca->regmap, PCA9685_MODE1, MODE1_SLEEP,
356 MODE1_SLEEP);
357
358 return pwmchip_remove(&pca->chip);
359}
360
361static const struct i2c_device_id pca9685_id[] = {
362 { "pca9685", 0 },
363 { /* sentinel */ },
364};
365MODULE_DEVICE_TABLE(i2c, pca9685_id);
366
367#ifdef CONFIG_ACPI
368static const struct acpi_device_id pca9685_acpi_ids[] = {
369 { "INT3492", 0 },
370 { /* sentinel */ },
371};
372MODULE_DEVICE_TABLE(acpi, pca9685_acpi_ids);
373#endif
374
375#ifdef CONFIG_OF
376static const struct of_device_id pca9685_dt_ids[] = {
377 { .compatible = "nxp,pca9685-pwm", },
378 { /* sentinel */ }
379};
380MODULE_DEVICE_TABLE(of, pca9685_dt_ids);
381#endif
382
383static struct i2c_driver pca9685_i2c_driver = {
384 .driver = {
385 .name = "pca9685-pwm",
386 .acpi_match_table = ACPI_PTR(pca9685_acpi_ids),
387 .of_match_table = of_match_ptr(pca9685_dt_ids),
388 },
389 .probe = pca9685_pwm_probe,
390 .remove = pca9685_pwm_remove,
391 .id_table = pca9685_id,
392};
393
394module_i2c_driver(pca9685_i2c_driver);
395
396MODULE_AUTHOR("Steffen Trumtrar <s.trumtrar@pengutronix.de>");
397MODULE_DESCRIPTION("PWM driver for PCA9685");
398MODULE_LICENSE("GPL");
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Driver for PCA9685 16-channel 12-bit PWM LED controller
4 *
5 * Copyright (C) 2013 Steffen Trumtrar <s.trumtrar@pengutronix.de>
6 * Copyright (C) 2015 Clemens Gruber <clemens.gruber@pqgruber.com>
7 *
8 * based on the pwm-twl-led.c driver
9 */
10
11#include <linux/acpi.h>
12#include <linux/gpio/driver.h>
13#include <linux/i2c.h>
14#include <linux/module.h>
15#include <linux/mutex.h>
16#include <linux/platform_device.h>
17#include <linux/property.h>
18#include <linux/pwm.h>
19#include <linux/regmap.h>
20#include <linux/slab.h>
21#include <linux/delay.h>
22#include <linux/pm_runtime.h>
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 */
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
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
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
69struct pca9685 {
70 struct pwm_chip chip;
71 struct regmap *regmap;
72 int duty_ns;
73 int period_ns;
74#if IS_ENABLED(CONFIG_GPIOLIB)
75 struct mutex lock;
76 struct gpio_chip gpio;
77#endif
78};
79
80static inline struct pca9685 *to_pca(struct pwm_chip *chip)
81{
82 return container_of(chip, struct pca9685, chip);
83}
84
85#if IS_ENABLED(CONFIG_GPIOLIB)
86static 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);
103 pm_runtime_get_sync(pca->chip.dev);
104 return 0;
105}
106
107static 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
133static 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
144static 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
159static 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];
168 mutex_unlock(&pca->lock);
169}
170
171static int pca9685_pwm_gpio_get_direction(struct gpio_chip *chip,
172 unsigned int offset)
173{
174 /* Always out */
175 return 0;
176}
177
178static int pca9685_pwm_gpio_direction_input(struct gpio_chip *gpio,
179 unsigned int offset)
180{
181 return -EINVAL;
182}
183
184static 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 */
198static 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
220static inline bool pca9685_pwm_is_gpio(struct pca9685 *pca,
221 struct pwm_device *pwm)
222{
223 return false;
224}
225
226static inline int pca9685_pwm_gpio_probe(struct pca9685 *pca)
227{
228 return 0;
229}
230#endif
231
232static void pca9685_set_sleep_mode(struct pca9685 *pca, bool enable)
233{
234 regmap_update_bits(pca->regmap, PCA9685_MODE1,
235 MODE1_SLEEP, enable ? MODE1_SLEEP : 0);
236 if (!enable) {
237 /* Wait 500us for the oscillator to be back up */
238 udelay(500);
239 }
240}
241
242static 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;
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) {
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 */
262 /* Put chip into sleep mode */
263 pca9685_set_sleep_mode(pca, true);
264
265 /* Change the chip-wide output frequency */
266 regmap_write(pca->regmap, PCA9685_PRESCALE, prescale);
267
268 /* Wake the chip up */
269 pca9685_set_sleep_mode(pca, false);
270
271 pca->period_ns = period_ns;
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;
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) {
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 */
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
319 duty = PCA9685_COUNTER_RANGE * (unsigned long long)duty_ns;
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
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
344 return 0;
345}
346
347static 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
384static 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
405static int pca9685_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
406{
407 struct pca9685 *pca = to_pca(chip);
408
409 if (pca9685_pwm_is_gpio(pca, pwm))
410 return -EBUSY;
411 pm_runtime_get_sync(chip->dev);
412
413 return 0;
414}
415
416static void pca9685_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
417{
418 pca9685_pwm_disable(chip, pwm);
419 pm_runtime_put(chip->dev);
420}
421
422static 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,
428 .owner = THIS_MODULE,
429};
430
431static const struct regmap_config pca9685_regmap_i2c_config = {
432 .reg_bits = 8,
433 .val_bits = 8,
434 .max_register = PCA9685_NUMREGS,
435 .cache_type = REGCACHE_NONE,
436};
437
438static int pca9685_pwm_probe(struct i2c_client *client,
439 const struct i2c_device_id *id)
440{
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 }
456 pca->duty_ns = 0;
457 pca->period_ns = PCA9685_DEFAULT_PERIOD;
458
459 i2c_set_clientdata(client, pca);
460
461 regmap_read(pca->regmap, PCA9685_MODE2, &mode2);
462
463 if (device_property_read_bool(&client->dev, "invert"))
464 mode2 |= MODE2_INVRT;
465 else
466 mode2 &= ~MODE2_INVRT;
467
468 if (device_property_read_bool(&client->dev, "open-drain"))
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;
485
486 ret = pwmchip_add(&pca->chip);
487 if (ret < 0)
488 return ret;
489
490 ret = pca9685_pwm_gpio_probe(pca);
491 if (ret < 0) {
492 pwmchip_remove(&pca->chip);
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);
503
504 return 0;
505}
506
507static int pca9685_pwm_remove(struct i2c_client *client)
508{
509 struct pca9685 *pca = i2c_get_clientdata(client);
510 int ret;
511
512 ret = pwmchip_remove(&pca->chip);
513 if (ret)
514 return ret;
515 pm_runtime_disable(&client->dev);
516 return 0;
517}
518
519#ifdef CONFIG_PM
520static 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
525 pca9685_set_sleep_mode(pca, true);
526 return 0;
527}
528
529static 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
534 pca9685_set_sleep_mode(pca, false);
535 return 0;
536}
537#endif
538
539static const struct i2c_device_id pca9685_id[] = {
540 { "pca9685", 0 },
541 { /* sentinel */ },
542};
543MODULE_DEVICE_TABLE(i2c, pca9685_id);
544
545#ifdef CONFIG_ACPI
546static const struct acpi_device_id pca9685_acpi_ids[] = {
547 { "INT3492", 0 },
548 { /* sentinel */ },
549};
550MODULE_DEVICE_TABLE(acpi, pca9685_acpi_ids);
551#endif
552
553#ifdef CONFIG_OF
554static const struct of_device_id pca9685_dt_ids[] = {
555 { .compatible = "nxp,pca9685-pwm", },
556 { /* sentinel */ }
557};
558MODULE_DEVICE_TABLE(of, pca9685_dt_ids);
559#endif
560
561static 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
566static struct i2c_driver pca9685_i2c_driver = {
567 .driver = {
568 .name = "pca9685-pwm",
569 .acpi_match_table = ACPI_PTR(pca9685_acpi_ids),
570 .of_match_table = of_match_ptr(pca9685_dt_ids),
571 .pm = &pca9685_pwm_pm,
572 },
573 .probe = pca9685_pwm_probe,
574 .remove = pca9685_pwm_remove,
575 .id_table = pca9685_id,
576};
577
578module_i2c_driver(pca9685_i2c_driver);
579
580MODULE_AUTHOR("Steffen Trumtrar <s.trumtrar@pengutronix.de>");
581MODULE_DESCRIPTION("PWM driver for PCA9685");
582MODULE_LICENSE("GPL");