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