1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Driver for TWL4030/6030 Generic Pulse Width Modulator
4 *
5 * Copyright (C) 2012 Texas Instruments
6 * Author: Peter Ujfalusi <peter.ujfalusi@ti.com>
7 */
8
9 #include <linux/module.h>
10 #include <linux/of.h>
11 #include <linux/platform_device.h>
12 #include <linux/pwm.h>
13 #include <linux/mfd/twl.h>
14 #include <linux/slab.h>
15
16 /*
17 * This driver handles the PWMs of TWL4030 and TWL6030.
18 * The TRM names for the PWMs on TWL4030 are: PWM0, PWM1
19 * TWL6030 also have two PWMs named in the TRM as PWM1, PWM2
20 */
21
22 #define TWL_PWM_MAX 0x7f
23
24 /* Registers, bits and macro for TWL4030 */
25 #define TWL4030_GPBR1_REG 0x0c
26 #define TWL4030_PMBR1_REG 0x0d
27
28 /* GPBR1 register bits */
29 #define TWL4030_PWMXCLK_ENABLE (1 << 0)
30 #define TWL4030_PWMX_ENABLE (1 << 2)
31 #define TWL4030_PWMX_BITS (TWL4030_PWMX_ENABLE | TWL4030_PWMXCLK_ENABLE)
32 #define TWL4030_PWM_TOGGLE(pwm, x) ((x) << (pwm))
33
34 /* PMBR1 register bits */
35 #define TWL4030_GPIO6_PWM0_MUTE_MASK (0x03 << 2)
36 #define TWL4030_GPIO6_PWM0_MUTE_PWM0 (0x01 << 2)
37 #define TWL4030_GPIO7_VIBRASYNC_PWM1_MASK (0x03 << 4)
38 #define TWL4030_GPIO7_VIBRASYNC_PWM1_PWM1 (0x03 << 4)
39
40 /* Register, bits and macro for TWL6030 */
41 #define TWL6030_TOGGLE3_REG 0x92
42
43 #define TWL6030_PWMXR (1 << 0)
44 #define TWL6030_PWMXS (1 << 1)
45 #define TWL6030_PWMXEN (1 << 2)
46 #define TWL6030_PWM_TOGGLE(pwm, x) ((x) << (pwm * 3))
47
48 struct twl_pwm_chip {
49 struct mutex mutex;
50 u8 twl6030_toggle3;
51 u8 twl4030_pwm_mux;
52 };
53
to_twl(struct pwm_chip * chip)54 static inline struct twl_pwm_chip *to_twl(struct pwm_chip *chip)
55 {
56 return pwmchip_get_drvdata(chip);
57 }
58
twl_pwm_config(struct pwm_chip * chip,struct pwm_device * pwm,u64 duty_ns,u64 period_ns)59 static int twl_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
60 u64 duty_ns, u64 period_ns)
61 {
62 int duty_cycle = DIV64_U64_ROUND_UP(duty_ns * TWL_PWM_MAX, period_ns) + 1;
63 u8 pwm_config[2] = { 1, 0 };
64 int base, ret;
65
66 /*
67 * To configure the duty period:
68 * On-cycle is set to 1 (the minimum allowed value)
69 * The off time of 0 is not configurable, so the mapping is:
70 * 0 -> off cycle = 2,
71 * 1 -> off cycle = 2,
72 * 2 -> off cycle = 3,
73 * 126 - > off cycle 127,
74 * 127 - > off cycle 1
75 * When on cycle == off cycle the PWM will be always on
76 */
77 if (duty_cycle == 1)
78 duty_cycle = 2;
79 else if (duty_cycle > TWL_PWM_MAX)
80 duty_cycle = 1;
81
82 base = pwm->hwpwm * 3;
83
84 pwm_config[1] = duty_cycle;
85
86 ret = twl_i2c_write(TWL_MODULE_PWM, pwm_config, base, 2);
87 if (ret < 0)
88 dev_err(pwmchip_parent(chip), "%s: Failed to configure PWM\n", pwm->label);
89
90 return ret;
91 }
92
twl4030_pwm_enable(struct pwm_chip * chip,struct pwm_device * pwm)93 static int twl4030_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
94 {
95 struct twl_pwm_chip *twl = to_twl(chip);
96 int ret;
97 u8 val;
98
99 mutex_lock(&twl->mutex);
100 ret = twl_i2c_read_u8(TWL4030_MODULE_INTBR, &val, TWL4030_GPBR1_REG);
101 if (ret < 0) {
102 dev_err(pwmchip_parent(chip), "%s: Failed to read GPBR1\n", pwm->label);
103 goto out;
104 }
105
106 val |= TWL4030_PWM_TOGGLE(pwm->hwpwm, TWL4030_PWMXCLK_ENABLE);
107
108 ret = twl_i2c_write_u8(TWL4030_MODULE_INTBR, val, TWL4030_GPBR1_REG);
109 if (ret < 0)
110 dev_err(pwmchip_parent(chip), "%s: Failed to enable PWM\n", pwm->label);
111
112 val |= TWL4030_PWM_TOGGLE(pwm->hwpwm, TWL4030_PWMX_ENABLE);
113
114 ret = twl_i2c_write_u8(TWL4030_MODULE_INTBR, val, TWL4030_GPBR1_REG);
115 if (ret < 0)
116 dev_err(pwmchip_parent(chip), "%s: Failed to enable PWM\n", pwm->label);
117
118 out:
119 mutex_unlock(&twl->mutex);
120 return ret;
121 }
122
twl4030_pwm_disable(struct pwm_chip * chip,struct pwm_device * pwm)123 static void twl4030_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
124 {
125 struct twl_pwm_chip *twl = to_twl(chip);
126 int ret;
127 u8 val;
128
129 mutex_lock(&twl->mutex);
130 ret = twl_i2c_read_u8(TWL4030_MODULE_INTBR, &val, TWL4030_GPBR1_REG);
131 if (ret < 0) {
132 dev_err(pwmchip_parent(chip), "%s: Failed to read GPBR1\n", pwm->label);
133 goto out;
134 }
135
136 val &= ~TWL4030_PWM_TOGGLE(pwm->hwpwm, TWL4030_PWMX_ENABLE);
137
138 ret = twl_i2c_write_u8(TWL4030_MODULE_INTBR, val, TWL4030_GPBR1_REG);
139 if (ret < 0)
140 dev_err(pwmchip_parent(chip), "%s: Failed to disable PWM\n", pwm->label);
141
142 val &= ~TWL4030_PWM_TOGGLE(pwm->hwpwm, TWL4030_PWMXCLK_ENABLE);
143
144 ret = twl_i2c_write_u8(TWL4030_MODULE_INTBR, val, TWL4030_GPBR1_REG);
145 if (ret < 0)
146 dev_err(pwmchip_parent(chip), "%s: Failed to disable PWM\n", pwm->label);
147
148 out:
149 mutex_unlock(&twl->mutex);
150 }
151
twl4030_pwm_request(struct pwm_chip * chip,struct pwm_device * pwm)152 static int twl4030_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
153 {
154 struct twl_pwm_chip *twl = to_twl(chip);
155 int ret;
156 u8 val, mask, bits;
157
158 if (pwm->hwpwm == 1) {
159 mask = TWL4030_GPIO7_VIBRASYNC_PWM1_MASK;
160 bits = TWL4030_GPIO7_VIBRASYNC_PWM1_PWM1;
161 } else {
162 mask = TWL4030_GPIO6_PWM0_MUTE_MASK;
163 bits = TWL4030_GPIO6_PWM0_MUTE_PWM0;
164 }
165
166 mutex_lock(&twl->mutex);
167 ret = twl_i2c_read_u8(TWL4030_MODULE_INTBR, &val, TWL4030_PMBR1_REG);
168 if (ret < 0) {
169 dev_err(pwmchip_parent(chip), "%s: Failed to read PMBR1\n", pwm->label);
170 goto out;
171 }
172
173 /* Save the current MUX configuration for the PWM */
174 twl->twl4030_pwm_mux &= ~mask;
175 twl->twl4030_pwm_mux |= (val & mask);
176
177 /* Select PWM functionality */
178 val &= ~mask;
179 val |= bits;
180
181 ret = twl_i2c_write_u8(TWL4030_MODULE_INTBR, val, TWL4030_PMBR1_REG);
182 if (ret < 0)
183 dev_err(pwmchip_parent(chip), "%s: Failed to request PWM\n", pwm->label);
184
185 out:
186 mutex_unlock(&twl->mutex);
187 return ret;
188 }
189
twl4030_pwm_free(struct pwm_chip * chip,struct pwm_device * pwm)190 static void twl4030_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
191 {
192 struct twl_pwm_chip *twl = to_twl(chip);
193 int ret;
194 u8 val, mask;
195
196 if (pwm->hwpwm == 1)
197 mask = TWL4030_GPIO7_VIBRASYNC_PWM1_MASK;
198 else
199 mask = TWL4030_GPIO6_PWM0_MUTE_MASK;
200
201 mutex_lock(&twl->mutex);
202 ret = twl_i2c_read_u8(TWL4030_MODULE_INTBR, &val, TWL4030_PMBR1_REG);
203 if (ret < 0) {
204 dev_err(pwmchip_parent(chip), "%s: Failed to read PMBR1\n", pwm->label);
205 goto out;
206 }
207
208 /* Restore the MUX configuration for the PWM */
209 val &= ~mask;
210 val |= (twl->twl4030_pwm_mux & mask);
211
212 ret = twl_i2c_write_u8(TWL4030_MODULE_INTBR, val, TWL4030_PMBR1_REG);
213 if (ret < 0)
214 dev_err(pwmchip_parent(chip), "%s: Failed to free PWM\n", pwm->label);
215
216 out:
217 mutex_unlock(&twl->mutex);
218 }
219
twl6030_pwm_enable(struct pwm_chip * chip,struct pwm_device * pwm)220 static int twl6030_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
221 {
222 struct twl_pwm_chip *twl = to_twl(chip);
223 int ret;
224 u8 val;
225
226 mutex_lock(&twl->mutex);
227 val = twl->twl6030_toggle3;
228 val |= TWL6030_PWM_TOGGLE(pwm->hwpwm, TWL6030_PWMXS | TWL6030_PWMXEN);
229 val &= ~TWL6030_PWM_TOGGLE(pwm->hwpwm, TWL6030_PWMXR);
230
231 ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, TWL6030_TOGGLE3_REG);
232 if (ret < 0) {
233 dev_err(pwmchip_parent(chip), "%s: Failed to enable PWM\n", pwm->label);
234 goto out;
235 }
236
237 twl->twl6030_toggle3 = val;
238 out:
239 mutex_unlock(&twl->mutex);
240 return ret;
241 }
242
twl6030_pwm_disable(struct pwm_chip * chip,struct pwm_device * pwm)243 static void twl6030_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
244 {
245 struct twl_pwm_chip *twl = to_twl(chip);
246 int ret;
247 u8 val;
248
249 mutex_lock(&twl->mutex);
250 val = twl->twl6030_toggle3;
251 val |= TWL6030_PWM_TOGGLE(pwm->hwpwm, TWL6030_PWMXR);
252 val &= ~TWL6030_PWM_TOGGLE(pwm->hwpwm, TWL6030_PWMXS | TWL6030_PWMXEN);
253
254 ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, TWL6030_TOGGLE3_REG);
255 if (ret < 0) {
256 dev_err(pwmchip_parent(chip), "%s: Failed to disable PWM\n", pwm->label);
257 goto out;
258 }
259
260 val |= TWL6030_PWM_TOGGLE(pwm->hwpwm, TWL6030_PWMXEN);
261
262 ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, TWL6030_TOGGLE3_REG);
263 if (ret < 0) {
264 dev_err(pwmchip_parent(chip), "%s: Failed to disable PWM\n", pwm->label);
265 goto out;
266 }
267
268 val &= ~TWL6030_PWM_TOGGLE(pwm->hwpwm, TWL6030_PWMXEN);
269
270 ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, TWL6030_TOGGLE3_REG);
271 if (ret < 0) {
272 dev_err(pwmchip_parent(chip), "%s: Failed to disable PWM\n", pwm->label);
273 goto out;
274 }
275
276 twl->twl6030_toggle3 = val;
277 out:
278 mutex_unlock(&twl->mutex);
279 }
280
twl4030_pwm_apply(struct pwm_chip * chip,struct pwm_device * pwm,const struct pwm_state * state)281 static int twl4030_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
282 const struct pwm_state *state)
283 {
284 int err;
285
286 if (state->polarity != PWM_POLARITY_NORMAL)
287 return -EINVAL;
288
289 if (!state->enabled) {
290 if (pwm->state.enabled)
291 twl4030_pwm_disable(chip, pwm);
292
293 return 0;
294 }
295
296 err = twl_pwm_config(chip, pwm, state->duty_cycle, state->period);
297 if (err)
298 return err;
299
300 if (!pwm->state.enabled)
301 err = twl4030_pwm_enable(chip, pwm);
302
303 return err;
304 }
305
twl6030_pwm_apply(struct pwm_chip * chip,struct pwm_device * pwm,const struct pwm_state * state)306 static int twl6030_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
307 const struct pwm_state *state)
308 {
309 int err;
310
311 if (state->polarity != PWM_POLARITY_NORMAL)
312 return -EINVAL;
313
314 if (!state->enabled) {
315 if (pwm->state.enabled)
316 twl6030_pwm_disable(chip, pwm);
317
318 return 0;
319 }
320
321 err = twl_pwm_config(chip, pwm, state->duty_cycle, state->period);
322 if (err)
323 return err;
324
325 if (!pwm->state.enabled)
326 err = twl6030_pwm_enable(chip, pwm);
327
328 return err;
329 }
330
331 static const struct pwm_ops twl4030_pwm_ops = {
332 .apply = twl4030_pwm_apply,
333 .request = twl4030_pwm_request,
334 .free = twl4030_pwm_free,
335 };
336
337 static const struct pwm_ops twl6030_pwm_ops = {
338 .apply = twl6030_pwm_apply,
339 };
340
twl_pwm_probe(struct platform_device * pdev)341 static int twl_pwm_probe(struct platform_device *pdev)
342 {
343 struct pwm_chip *chip;
344 struct twl_pwm_chip *twl;
345
346 chip = devm_pwmchip_alloc(&pdev->dev, 2, sizeof(*twl));
347 if (IS_ERR(chip))
348 return PTR_ERR(chip);
349 twl = to_twl(chip);
350
351 if (twl_class_is_4030())
352 chip->ops = &twl4030_pwm_ops;
353 else
354 chip->ops = &twl6030_pwm_ops;
355
356 mutex_init(&twl->mutex);
357
358 return devm_pwmchip_add(&pdev->dev, chip);
359 }
360
361 #ifdef CONFIG_OF
362 static const struct of_device_id twl_pwm_of_match[] = {
363 { .compatible = "ti,twl4030-pwm" },
364 { .compatible = "ti,twl6030-pwm" },
365 { },
366 };
367 MODULE_DEVICE_TABLE(of, twl_pwm_of_match);
368 #endif
369
370 static struct platform_driver twl_pwm_driver = {
371 .driver = {
372 .name = "twl-pwm",
373 .of_match_table = of_match_ptr(twl_pwm_of_match),
374 },
375 .probe = twl_pwm_probe,
376 };
377 module_platform_driver(twl_pwm_driver);
378
379 MODULE_AUTHOR("Peter Ujfalusi <peter.ujfalusi@ti.com>");
380 MODULE_DESCRIPTION("PWM driver for TWL4030 and TWL6030");
381 MODULE_ALIAS("platform:twl-pwm");
382 MODULE_LICENSE("GPL");
383