1 #ifndef __LINUX_PWM_H 2 #define __LINUX_PWM_H 3 4 #include <linux/err.h> 5 #include <linux/of.h> 6 7 struct pwm_device; 8 struct seq_file; 9 10 #if IS_ENABLED(CONFIG_PWM) 11 /* 12 * pwm_request - request a PWM device 13 */ 14 struct pwm_device *pwm_request(int pwm_id, const char *label); 15 16 /* 17 * pwm_free - free a PWM device 18 */ 19 void pwm_free(struct pwm_device *pwm); 20 21 /* 22 * pwm_config - change a PWM device configuration 23 */ 24 int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns); 25 26 /* 27 * pwm_enable - start a PWM output toggling 28 */ 29 int pwm_enable(struct pwm_device *pwm); 30 31 /* 32 * pwm_disable - stop a PWM output toggling 33 */ 34 void pwm_disable(struct pwm_device *pwm); 35 #else 36 static inline struct pwm_device *pwm_request(int pwm_id, const char *label) 37 { 38 return ERR_PTR(-ENODEV); 39 } 40 41 static inline void pwm_free(struct pwm_device *pwm) 42 { 43 } 44 45 static inline int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns) 46 { 47 return -EINVAL; 48 } 49 50 static inline int pwm_enable(struct pwm_device *pwm) 51 { 52 return -EINVAL; 53 } 54 55 static inline void pwm_disable(struct pwm_device *pwm) 56 { 57 } 58 #endif 59 60 struct pwm_chip; 61 62 /** 63 * enum pwm_polarity - polarity of a PWM signal 64 * @PWM_POLARITY_NORMAL: a high signal for the duration of the duty- 65 * cycle, followed by a low signal for the remainder of the pulse 66 * period 67 * @PWM_POLARITY_INVERSED: a low signal for the duration of the duty- 68 * cycle, followed by a high signal for the remainder of the pulse 69 * period 70 */ 71 enum pwm_polarity { 72 PWM_POLARITY_NORMAL, 73 PWM_POLARITY_INVERSED, 74 }; 75 76 enum { 77 PWMF_REQUESTED = 1 << 0, 78 PWMF_ENABLED = 1 << 1, 79 PWMF_EXPORTED = 1 << 2, 80 }; 81 82 struct pwm_device { 83 const char *label; 84 unsigned long flags; 85 unsigned int hwpwm; 86 unsigned int pwm; 87 struct pwm_chip *chip; 88 void *chip_data; 89 90 unsigned int period; /* in nanoseconds */ 91 unsigned int duty_cycle; /* in nanoseconds */ 92 enum pwm_polarity polarity; 93 }; 94 95 static inline void pwm_set_period(struct pwm_device *pwm, unsigned int period) 96 { 97 if (pwm) 98 pwm->period = period; 99 } 100 101 static inline unsigned int pwm_get_period(struct pwm_device *pwm) 102 { 103 return pwm ? pwm->period : 0; 104 } 105 106 static inline void pwm_set_duty_cycle(struct pwm_device *pwm, unsigned int duty) 107 { 108 if (pwm) 109 pwm->duty_cycle = duty; 110 } 111 112 static inline unsigned int pwm_get_duty_cycle(struct pwm_device *pwm) 113 { 114 return pwm ? pwm->duty_cycle : 0; 115 } 116 117 /* 118 * pwm_set_polarity - configure the polarity of a PWM signal 119 */ 120 int pwm_set_polarity(struct pwm_device *pwm, enum pwm_polarity polarity); 121 122 /** 123 * struct pwm_ops - PWM controller operations 124 * @request: optional hook for requesting a PWM 125 * @free: optional hook for freeing a PWM 126 * @config: configure duty cycles and period length for this PWM 127 * @set_polarity: configure the polarity of this PWM 128 * @enable: enable PWM output toggling 129 * @disable: disable PWM output toggling 130 * @dbg_show: optional routine to show contents in debugfs 131 * @owner: helps prevent removal of modules exporting active PWMs 132 */ 133 struct pwm_ops { 134 int (*request)(struct pwm_chip *chip, 135 struct pwm_device *pwm); 136 void (*free)(struct pwm_chip *chip, 137 struct pwm_device *pwm); 138 int (*config)(struct pwm_chip *chip, 139 struct pwm_device *pwm, 140 int duty_ns, int period_ns); 141 int (*set_polarity)(struct pwm_chip *chip, 142 struct pwm_device *pwm, 143 enum pwm_polarity polarity); 144 int (*enable)(struct pwm_chip *chip, 145 struct pwm_device *pwm); 146 void (*disable)(struct pwm_chip *chip, 147 struct pwm_device *pwm); 148 #ifdef CONFIG_DEBUG_FS 149 void (*dbg_show)(struct pwm_chip *chip, 150 struct seq_file *s); 151 #endif 152 struct module *owner; 153 }; 154 155 /** 156 * struct pwm_chip - abstract a PWM controller 157 * @dev: device providing the PWMs 158 * @list: list node for internal use 159 * @ops: callbacks for this PWM controller 160 * @base: number of first PWM controlled by this chip 161 * @npwm: number of PWMs controlled by this chip 162 * @pwms: array of PWM devices allocated by the framework 163 * @can_sleep: must be true if the .config(), .enable() or .disable() 164 * operations may sleep 165 */ 166 struct pwm_chip { 167 struct device *dev; 168 struct list_head list; 169 const struct pwm_ops *ops; 170 int base; 171 unsigned int npwm; 172 173 struct pwm_device *pwms; 174 175 struct pwm_device * (*of_xlate)(struct pwm_chip *pc, 176 const struct of_phandle_args *args); 177 unsigned int of_pwm_n_cells; 178 bool can_sleep; 179 }; 180 181 #if IS_ENABLED(CONFIG_PWM) 182 int pwm_set_chip_data(struct pwm_device *pwm, void *data); 183 void *pwm_get_chip_data(struct pwm_device *pwm); 184 185 int pwmchip_add_with_polarity(struct pwm_chip *chip, 186 enum pwm_polarity polarity); 187 int pwmchip_add(struct pwm_chip *chip); 188 int pwmchip_remove(struct pwm_chip *chip); 189 struct pwm_device *pwm_request_from_chip(struct pwm_chip *chip, 190 unsigned int index, 191 const char *label); 192 193 struct pwm_device *of_pwm_xlate_with_flags(struct pwm_chip *pc, 194 const struct of_phandle_args *args); 195 196 struct pwm_device *pwm_get(struct device *dev, const char *con_id); 197 struct pwm_device *of_pwm_get(struct device_node *np, const char *con_id); 198 void pwm_put(struct pwm_device *pwm); 199 200 struct pwm_device *devm_pwm_get(struct device *dev, const char *con_id); 201 struct pwm_device *devm_of_pwm_get(struct device *dev, struct device_node *np, 202 const char *con_id); 203 void devm_pwm_put(struct device *dev, struct pwm_device *pwm); 204 205 bool pwm_can_sleep(struct pwm_device *pwm); 206 #else 207 static inline int pwm_set_chip_data(struct pwm_device *pwm, void *data) 208 { 209 return -EINVAL; 210 } 211 212 static inline void *pwm_get_chip_data(struct pwm_device *pwm) 213 { 214 return NULL; 215 } 216 217 static inline int pwmchip_add(struct pwm_chip *chip) 218 { 219 return -EINVAL; 220 } 221 222 static inline int pwmchip_add_inversed(struct pwm_chip *chip) 223 { 224 return -EINVAL; 225 } 226 227 static inline int pwmchip_remove(struct pwm_chip *chip) 228 { 229 return -EINVAL; 230 } 231 232 static inline struct pwm_device *pwm_request_from_chip(struct pwm_chip *chip, 233 unsigned int index, 234 const char *label) 235 { 236 return ERR_PTR(-ENODEV); 237 } 238 239 static inline struct pwm_device *pwm_get(struct device *dev, 240 const char *consumer) 241 { 242 return ERR_PTR(-ENODEV); 243 } 244 245 static inline struct pwm_device *of_pwm_get(struct device_node *np, 246 const char *con_id) 247 { 248 return ERR_PTR(-ENODEV); 249 } 250 251 static inline void pwm_put(struct pwm_device *pwm) 252 { 253 } 254 255 static inline struct pwm_device *devm_pwm_get(struct device *dev, 256 const char *consumer) 257 { 258 return ERR_PTR(-ENODEV); 259 } 260 261 static inline struct pwm_device *devm_of_pwm_get(struct device *dev, 262 struct device_node *np, 263 const char *con_id) 264 { 265 return ERR_PTR(-ENODEV); 266 } 267 268 static inline void devm_pwm_put(struct device *dev, struct pwm_device *pwm) 269 { 270 } 271 272 static inline bool pwm_can_sleep(struct pwm_device *pwm) 273 { 274 return false; 275 } 276 #endif 277 278 struct pwm_lookup { 279 struct list_head list; 280 const char *provider; 281 unsigned int index; 282 const char *dev_id; 283 const char *con_id; 284 unsigned int period; 285 enum pwm_polarity polarity; 286 }; 287 288 #define PWM_LOOKUP(_provider, _index, _dev_id, _con_id, _period, _polarity) \ 289 { \ 290 .provider = _provider, \ 291 .index = _index, \ 292 .dev_id = _dev_id, \ 293 .con_id = _con_id, \ 294 .period = _period, \ 295 .polarity = _polarity \ 296 } 297 298 #if IS_ENABLED(CONFIG_PWM) 299 void pwm_add_table(struct pwm_lookup *table, size_t num); 300 void pwm_remove_table(struct pwm_lookup *table, size_t num); 301 #else 302 static inline void pwm_add_table(struct pwm_lookup *table, size_t num) 303 { 304 } 305 306 static inline void pwm_remove_table(struct pwm_lookup *table, size_t num) 307 { 308 } 309 #endif 310 311 #ifdef CONFIG_PWM_SYSFS 312 void pwmchip_sysfs_export(struct pwm_chip *chip); 313 void pwmchip_sysfs_unexport(struct pwm_chip *chip); 314 #else 315 static inline void pwmchip_sysfs_export(struct pwm_chip *chip) 316 { 317 } 318 319 static inline void pwmchip_sysfs_unexport(struct pwm_chip *chip) 320 { 321 } 322 #endif /* CONFIG_PWM_SYSFS */ 323 324 #endif /* __LINUX_PWM_H */ 325