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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Driver for TWL4030/6030 Generic Pulse Width Modulator4 *5 * Copyright (C) 2012 Texas Instruments6 * 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, PWM119 * TWL6030 also have two PWMs named in the TRM as PWM1, PWM220 */21 22#define TWL_PWM_MAX 0x7f23 24/* Registers, bits and macro for TWL4030 */25#define TWL4030_GPBR1_REG 0x0c26#define TWL4030_PMBR1_REG 0x0d27 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 0x9242 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 48struct twl_pwm_chip {49 struct mutex mutex;50 u8 twl6030_toggle3;51 u8 twl4030_pwm_mux;52};53 54static inline struct twl_pwm_chip *to_twl(struct pwm_chip *chip)55{56 return pwmchip_get_drvdata(chip);57}58 59static 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 175 * When on cycle == off cycle the PWM will be always on76 */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 93static 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 118out:119 mutex_unlock(&twl->mutex);120 return ret;121}122 123static 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 148out:149 mutex_unlock(&twl->mutex);150}151 152static 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 185out:186 mutex_unlock(&twl->mutex);187 return ret;188}189 190static 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 else199 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 216out:217 mutex_unlock(&twl->mutex);218}219 220static 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;238out:239 mutex_unlock(&twl->mutex);240 return ret;241}242 243static 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;277out:278 mutex_unlock(&twl->mutex);279}280 281static 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 306static 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 331static const struct pwm_ops twl4030_pwm_ops = {332 .apply = twl4030_pwm_apply,333 .request = twl4030_pwm_request,334 .free = twl4030_pwm_free,335};336 337static const struct pwm_ops twl6030_pwm_ops = {338 .apply = twl6030_pwm_apply,339};340 341static 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 else354 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_OF362static const struct of_device_id twl_pwm_of_match[] = {363 { .compatible = "ti,twl4030-pwm" },364 { .compatible = "ti,twl6030-pwm" },365 { },366};367MODULE_DEVICE_TABLE(of, twl_pwm_of_match);368#endif369 370static 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};377module_platform_driver(twl_pwm_driver);378 379MODULE_AUTHOR("Peter Ujfalusi <peter.ujfalusi@ti.com>");380MODULE_DESCRIPTION("PWM driver for TWL4030 and TWL6030");381MODULE_ALIAS("platform:twl-pwm");382MODULE_LICENSE("GPL");383