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 pwm_chip chip;
50 struct mutex mutex;
51 u8 twl6030_toggle3;
52 u8 twl4030_pwm_mux;
53 };
54
to_twl(struct pwm_chip * chip)55 static inline struct twl_pwm_chip *to_twl(struct pwm_chip *chip)
56 {
57 return container_of(chip, struct twl_pwm_chip, chip);
58 }
59
twl_pwm_config(struct pwm_chip * chip,struct pwm_device * pwm,int duty_ns,int period_ns)60 static int twl_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
61 int duty_ns, int period_ns)
62 {
63 int duty_cycle = DIV_ROUND_UP(duty_ns * TWL_PWM_MAX, period_ns) + 1;
64 u8 pwm_config[2] = { 1, 0 };
65 int base, ret;
66
67 /*
68 * To configure the duty period:
69 * On-cycle is set to 1 (the minimum allowed value)
70 * The off time of 0 is not configurable, so the mapping is:
71 * 0 -> off cycle = 2,
72 * 1 -> off cycle = 2,
73 * 2 -> off cycle = 3,
74 * 126 - > off cycle 127,
75 * 127 - > off cycle 1
76 * When on cycle == off cycle the PWM will be always on
77 */
78 if (duty_cycle == 1)
79 duty_cycle = 2;
80 else if (duty_cycle > TWL_PWM_MAX)
81 duty_cycle = 1;
82
83 base = pwm->hwpwm * 3;
84
85 pwm_config[1] = duty_cycle;
86
87 ret = twl_i2c_write(TWL_MODULE_PWM, pwm_config, base, 2);
88 if (ret < 0)
89 dev_err(chip->dev, "%s: Failed to configure PWM\n", pwm->label);
90
91 return ret;
92 }
93
twl4030_pwm_enable(struct pwm_chip * chip,struct pwm_device * pwm)94 static int twl4030_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
95 {
96 struct twl_pwm_chip *twl = to_twl(chip);
97 int ret;
98 u8 val;
99
100 mutex_lock(&twl->mutex);
101 ret = twl_i2c_read_u8(TWL4030_MODULE_INTBR, &val, TWL4030_GPBR1_REG);
102 if (ret < 0) {
103 dev_err(chip->dev, "%s: Failed to read GPBR1\n", pwm->label);
104 goto out;
105 }
106
107 val |= TWL4030_PWM_TOGGLE(pwm->hwpwm, TWL4030_PWMXCLK_ENABLE);
108
109 ret = twl_i2c_write_u8(TWL4030_MODULE_INTBR, val, TWL4030_GPBR1_REG);
110 if (ret < 0)
111 dev_err(chip->dev, "%s: Failed to enable PWM\n", pwm->label);
112
113 val |= TWL4030_PWM_TOGGLE(pwm->hwpwm, TWL4030_PWMX_ENABLE);
114
115 ret = twl_i2c_write_u8(TWL4030_MODULE_INTBR, val, TWL4030_GPBR1_REG);
116 if (ret < 0)
117 dev_err(chip->dev, "%s: Failed to enable PWM\n", pwm->label);
118
119 out:
120 mutex_unlock(&twl->mutex);
121 return ret;
122 }
123
twl4030_pwm_disable(struct pwm_chip * chip,struct pwm_device * pwm)124 static void twl4030_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
125 {
126 struct twl_pwm_chip *twl = to_twl(chip);
127 int ret;
128 u8 val;
129
130 mutex_lock(&twl->mutex);
131 ret = twl_i2c_read_u8(TWL4030_MODULE_INTBR, &val, TWL4030_GPBR1_REG);
132 if (ret < 0) {
133 dev_err(chip->dev, "%s: Failed to read GPBR1\n", pwm->label);
134 goto out;
135 }
136
137 val &= ~TWL4030_PWM_TOGGLE(pwm->hwpwm, TWL4030_PWMX_ENABLE);
138
139 ret = twl_i2c_write_u8(TWL4030_MODULE_INTBR, val, TWL4030_GPBR1_REG);
140 if (ret < 0)
141 dev_err(chip->dev, "%s: Failed to disable PWM\n", pwm->label);
142
143 val &= ~TWL4030_PWM_TOGGLE(pwm->hwpwm, TWL4030_PWMXCLK_ENABLE);
144
145 ret = twl_i2c_write_u8(TWL4030_MODULE_INTBR, val, TWL4030_GPBR1_REG);
146 if (ret < 0)
147 dev_err(chip->dev, "%s: Failed to disable PWM\n", pwm->label);
148
149 out:
150 mutex_unlock(&twl->mutex);
151 }
152
twl4030_pwm_request(struct pwm_chip * chip,struct pwm_device * pwm)153 static int twl4030_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
154 {
155 struct twl_pwm_chip *twl = to_twl(chip);
156 int ret;
157 u8 val, mask, bits;
158
159 if (pwm->hwpwm == 1) {
160 mask = TWL4030_GPIO7_VIBRASYNC_PWM1_MASK;
161 bits = TWL4030_GPIO7_VIBRASYNC_PWM1_PWM1;
162 } else {
163 mask = TWL4030_GPIO6_PWM0_MUTE_MASK;
164 bits = TWL4030_GPIO6_PWM0_MUTE_PWM0;
165 }
166
167 mutex_lock(&twl->mutex);
168 ret = twl_i2c_read_u8(TWL4030_MODULE_INTBR, &val, TWL4030_PMBR1_REG);
169 if (ret < 0) {
170 dev_err(chip->dev, "%s: Failed to read PMBR1\n", pwm->label);
171 goto out;
172 }
173
174 /* Save the current MUX configuration for the PWM */
175 twl->twl4030_pwm_mux &= ~mask;
176 twl->twl4030_pwm_mux |= (val & mask);
177
178 /* Select PWM functionality */
179 val &= ~mask;
180 val |= bits;
181
182 ret = twl_i2c_write_u8(TWL4030_MODULE_INTBR, val, TWL4030_PMBR1_REG);
183 if (ret < 0)
184 dev_err(chip->dev, "%s: Failed to request PWM\n", pwm->label);
185
186 out:
187 mutex_unlock(&twl->mutex);
188 return ret;
189 }
190
twl4030_pwm_free(struct pwm_chip * chip,struct pwm_device * pwm)191 static void twl4030_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
192 {
193 struct twl_pwm_chip *twl = to_twl(chip);
194 int ret;
195 u8 val, mask;
196
197 if (pwm->hwpwm == 1)
198 mask = TWL4030_GPIO7_VIBRASYNC_PWM1_MASK;
199 else
200 mask = TWL4030_GPIO6_PWM0_MUTE_MASK;
201
202 mutex_lock(&twl->mutex);
203 ret = twl_i2c_read_u8(TWL4030_MODULE_INTBR, &val, TWL4030_PMBR1_REG);
204 if (ret < 0) {
205 dev_err(chip->dev, "%s: Failed to read PMBR1\n", pwm->label);
206 goto out;
207 }
208
209 /* Restore the MUX configuration for the PWM */
210 val &= ~mask;
211 val |= (twl->twl4030_pwm_mux & mask);
212
213 ret = twl_i2c_write_u8(TWL4030_MODULE_INTBR, val, TWL4030_PMBR1_REG);
214 if (ret < 0)
215 dev_err(chip->dev, "%s: Failed to free PWM\n", pwm->label);
216
217 out:
218 mutex_unlock(&twl->mutex);
219 }
220
twl6030_pwm_enable(struct pwm_chip * chip,struct pwm_device * pwm)221 static int twl6030_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
222 {
223 struct twl_pwm_chip *twl = to_twl(chip);
224 int ret;
225 u8 val;
226
227 mutex_lock(&twl->mutex);
228 val = twl->twl6030_toggle3;
229 val |= TWL6030_PWM_TOGGLE(pwm->hwpwm, TWL6030_PWMXS | TWL6030_PWMXEN);
230 val &= ~TWL6030_PWM_TOGGLE(pwm->hwpwm, TWL6030_PWMXR);
231
232 ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, TWL6030_TOGGLE3_REG);
233 if (ret < 0) {
234 dev_err(chip->dev, "%s: Failed to enable PWM\n", pwm->label);
235 goto out;
236 }
237
238 twl->twl6030_toggle3 = val;
239 out:
240 mutex_unlock(&twl->mutex);
241 return ret;
242 }
243
twl6030_pwm_disable(struct pwm_chip * chip,struct pwm_device * pwm)244 static void twl6030_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
245 {
246 struct twl_pwm_chip *twl = to_twl(chip);
247 int ret;
248 u8 val;
249
250 mutex_lock(&twl->mutex);
251 val = twl->twl6030_toggle3;
252 val |= TWL6030_PWM_TOGGLE(pwm->hwpwm, TWL6030_PWMXR);
253 val &= ~TWL6030_PWM_TOGGLE(pwm->hwpwm, TWL6030_PWMXS | TWL6030_PWMXEN);
254
255 ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, TWL6030_TOGGLE3_REG);
256 if (ret < 0) {
257 dev_err(chip->dev, "%s: Failed to disable PWM\n", pwm->label);
258 goto out;
259 }
260
261 val |= TWL6030_PWM_TOGGLE(pwm->hwpwm, TWL6030_PWMXEN);
262
263 ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, TWL6030_TOGGLE3_REG);
264 if (ret < 0) {
265 dev_err(chip->dev, "%s: Failed to disable PWM\n", pwm->label);
266 goto out;
267 }
268
269 val &= ~TWL6030_PWM_TOGGLE(pwm->hwpwm, TWL6030_PWMXEN);
270
271 ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, val, TWL6030_TOGGLE3_REG);
272 if (ret < 0) {
273 dev_err(chip->dev, "%s: Failed to disable PWM\n", pwm->label);
274 goto out;
275 }
276
277 twl->twl6030_toggle3 = val;
278 out:
279 mutex_unlock(&twl->mutex);
280 }
281
282 static const struct pwm_ops twl4030_pwm_ops = {
283 .config = twl_pwm_config,
284 .enable = twl4030_pwm_enable,
285 .disable = twl4030_pwm_disable,
286 .request = twl4030_pwm_request,
287 .free = twl4030_pwm_free,
288 .owner = THIS_MODULE,
289 };
290
291 static const struct pwm_ops twl6030_pwm_ops = {
292 .config = twl_pwm_config,
293 .enable = twl6030_pwm_enable,
294 .disable = twl6030_pwm_disable,
295 .owner = THIS_MODULE,
296 };
297
twl_pwm_probe(struct platform_device * pdev)298 static int twl_pwm_probe(struct platform_device *pdev)
299 {
300 struct twl_pwm_chip *twl;
301
302 twl = devm_kzalloc(&pdev->dev, sizeof(*twl), GFP_KERNEL);
303 if (!twl)
304 return -ENOMEM;
305
306 if (twl_class_is_4030())
307 twl->chip.ops = &twl4030_pwm_ops;
308 else
309 twl->chip.ops = &twl6030_pwm_ops;
310
311 twl->chip.dev = &pdev->dev;
312 twl->chip.npwm = 2;
313
314 mutex_init(&twl->mutex);
315
316 return devm_pwmchip_add(&pdev->dev, &twl->chip);
317 }
318
319 #ifdef CONFIG_OF
320 static const struct of_device_id twl_pwm_of_match[] = {
321 { .compatible = "ti,twl4030-pwm" },
322 { .compatible = "ti,twl6030-pwm" },
323 { },
324 };
325 MODULE_DEVICE_TABLE(of, twl_pwm_of_match);
326 #endif
327
328 static struct platform_driver twl_pwm_driver = {
329 .driver = {
330 .name = "twl-pwm",
331 .of_match_table = of_match_ptr(twl_pwm_of_match),
332 },
333 .probe = twl_pwm_probe,
334 };
335 module_platform_driver(twl_pwm_driver);
336
337 MODULE_AUTHOR("Peter Ujfalusi <peter.ujfalusi@ti.com>");
338 MODULE_DESCRIPTION("PWM driver for TWL4030 and TWL6030");
339 MODULE_ALIAS("platform:twl-pwm");
340 MODULE_LICENSE("GPL");
341