| 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 | |
| 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 | |
| 60 | static int twl_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, |
| 61 | u64 duty_ns, u64 period_ns) |
| 62 | { |
| 63 | int duty_cycle = DIV64_U64_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 | |
| 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 | |
| 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 | |
| 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 | |
| 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 | |
| 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 | |
| 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 int twl4030_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, |
| 283 | const struct pwm_state *state) |
| 284 | { |
| 285 | int err; |
| 286 | |
| 287 | if (state->polarity != PWM_POLARITY_NORMAL) |
| 288 | return -EINVAL; |
| 289 | |
| 290 | if (!state->enabled) { |
| 291 | if (pwm->state.enabled) |
| 292 | twl4030_pwm_disable(chip, pwm); |
| 293 | |
| 294 | return 0; |
| 295 | } |
| 296 | |
| 297 | err = twl_pwm_config(pwm->chip, pwm, state->duty_cycle, state->period); |
| 298 | if (err) |
| 299 | return err; |
| 300 | |
| 301 | if (!pwm->state.enabled) |
| 302 | err = twl4030_pwm_enable(chip, pwm); |
| 303 | |
| 304 | return err; |
| 305 | } |
| 306 | |
| 307 | static int twl6030_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, |
| 308 | const struct pwm_state *state) |
| 309 | { |
| 310 | int err; |
| 311 | |
| 312 | if (state->polarity != PWM_POLARITY_NORMAL) |
| 313 | return -EINVAL; |
| 314 | |
| 315 | if (!state->enabled) { |
| 316 | if (pwm->state.enabled) |
| 317 | twl6030_pwm_disable(chip, pwm); |
| 318 | |
| 319 | return 0; |
| 320 | } |
| 321 | |
| 322 | err = twl_pwm_config(pwm->chip, pwm, state->duty_cycle, state->period); |
| 323 | if (err) |
| 324 | return err; |
| 325 | |
| 326 | if (!pwm->state.enabled) |
| 327 | err = twl6030_pwm_enable(chip, pwm); |
| 328 | |
| 329 | return err; |
| 330 | } |
| 331 | |
| 332 | static const struct pwm_ops twl4030_pwm_ops = { |
| 333 | .apply = twl4030_pwm_apply, |
| 334 | .request = twl4030_pwm_request, |
| 335 | .free = twl4030_pwm_free, |
| 336 | .owner = THIS_MODULE, |
| 337 | }; |
| 338 | |
| 339 | static const struct pwm_ops twl6030_pwm_ops = { |
| 340 | .apply = twl6030_pwm_apply, |
| 341 | .owner = THIS_MODULE, |
| 342 | }; |
| 343 | |
| 344 | static int twl_pwm_probe(struct platform_device *pdev) |
| 345 | { |
| 346 | struct twl_pwm_chip *twl; |
| 347 | |
| 348 | twl = devm_kzalloc(&pdev->dev, sizeof(*twl), GFP_KERNEL); |
| 349 | if (!twl) |
| 350 | return -ENOMEM; |
| 351 | |
| 352 | if (twl_class_is_4030()) |
| 353 | twl->chip.ops = &twl4030_pwm_ops; |
| 354 | else |
| 355 | twl->chip.ops = &twl6030_pwm_ops; |
| 356 | |
| 357 | twl->chip.dev = &pdev->dev; |
| 358 | twl->chip.npwm = 2; |
| 359 | |
| 360 | mutex_init(&twl->mutex); |
| 361 | |
| 362 | return devm_pwmchip_add(&pdev->dev, &twl->chip); |
| 363 | } |
| 364 | |
| 365 | #ifdef CONFIG_OF |
| 366 | static const struct of_device_id twl_pwm_of_match[] = { |
| 367 | { .compatible = "ti,twl4030-pwm" }, |
| 368 | { .compatible = "ti,twl6030-pwm" }, |
| 369 | { }, |
| 370 | }; |
| 371 | MODULE_DEVICE_TABLE(of, twl_pwm_of_match); |
| 372 | #endif |
| 373 | |
| 374 | static struct platform_driver twl_pwm_driver = { |
| 375 | .driver = { |
| 376 | .name = "twl-pwm", |
| 377 | .of_match_table = of_match_ptr(twl_pwm_of_match), |
| 378 | }, |
| 379 | .probe = twl_pwm_probe, |
| 380 | }; |
| 381 | module_platform_driver(twl_pwm_driver); |
| 382 | |
| 383 | MODULE_AUTHOR("Peter Ujfalusi <peter.ujfalusi@ti.com>"); |
| 384 | MODULE_DESCRIPTION("PWM driver for TWL4030 and TWL6030"); |
| 385 | MODULE_ALIAS("platform:twl-pwm"); |
| 386 | MODULE_LICENSE("GPL"); |