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) || IS_ENABLED(CONFIG_HAVE_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 }; 80 81 struct pwm_device { 82 const char *label; 83 unsigned long flags; 84 unsigned int hwpwm; 85 unsigned int pwm; 86 struct pwm_chip *chip; 87 void *chip_data; 88 89 unsigned int period; /* in nanoseconds */ 90 }; 91 92 static inline void pwm_set_period(struct pwm_device *pwm, unsigned int period) 93 { 94 if (pwm) 95 pwm->period = period; 96 } 97 98 static inline unsigned int pwm_get_period(struct pwm_device *pwm) 99 { 100 return pwm ? pwm->period : 0; 101 } 102 103 /* 104 * pwm_set_polarity - configure the polarity of a PWM signal 105 */ 106 int pwm_set_polarity(struct pwm_device *pwm, enum pwm_polarity polarity); 107 108 /** 109 * struct pwm_ops - PWM controller operations 110 * @request: optional hook for requesting a PWM 111 * @free: optional hook for freeing a PWM 112 * @config: configure duty cycles and period length for this PWM 113 * @set_polarity: configure the polarity of this PWM 114 * @enable: enable PWM output toggling 115 * @disable: disable PWM output toggling 116 * @dbg_show: optional routine to show contents in debugfs 117 * @owner: helps prevent removal of modules exporting active PWMs 118 */ 119 struct pwm_ops { 120 int (*request)(struct pwm_chip *chip, 121 struct pwm_device *pwm); 122 void (*free)(struct pwm_chip *chip, 123 struct pwm_device *pwm); 124 int (*config)(struct pwm_chip *chip, 125 struct pwm_device *pwm, 126 int duty_ns, int period_ns); 127 int (*set_polarity)(struct pwm_chip *chip, 128 struct pwm_device *pwm, 129 enum pwm_polarity polarity); 130 int (*enable)(struct pwm_chip *chip, 131 struct pwm_device *pwm); 132 void (*disable)(struct pwm_chip *chip, 133 struct pwm_device *pwm); 134 #ifdef CONFIG_DEBUG_FS 135 void (*dbg_show)(struct pwm_chip *chip, 136 struct seq_file *s); 137 #endif 138 struct module *owner; 139 }; 140 141 /** 142 * struct pwm_chip - abstract a PWM controller 143 * @dev: device providing the PWMs 144 * @list: list node for internal use 145 * @ops: callbacks for this PWM controller 146 * @base: number of first PWM controlled by this chip 147 * @npwm: number of PWMs controlled by this chip 148 * @pwms: array of PWM devices allocated by the framework 149 * @can_sleep: must be true if the .config(), .enable() or .disable() 150 * operations may sleep 151 */ 152 struct pwm_chip { 153 struct device *dev; 154 struct list_head list; 155 const struct pwm_ops *ops; 156 int base; 157 unsigned int npwm; 158 159 struct pwm_device *pwms; 160 161 struct pwm_device * (*of_xlate)(struct pwm_chip *pc, 162 const struct of_phandle_args *args); 163 unsigned int of_pwm_n_cells; 164 bool can_sleep; 165 }; 166 167 #if IS_ENABLED(CONFIG_PWM) 168 int pwm_set_chip_data(struct pwm_device *pwm, void *data); 169 void *pwm_get_chip_data(struct pwm_device *pwm); 170 171 int pwmchip_add(struct pwm_chip *chip); 172 int pwmchip_remove(struct pwm_chip *chip); 173 struct pwm_device *pwm_request_from_chip(struct pwm_chip *chip, 174 unsigned int index, 175 const char *label); 176 177 struct pwm_device *of_pwm_xlate_with_flags(struct pwm_chip *pc, 178 const struct of_phandle_args *args); 179 180 struct pwm_device *pwm_get(struct device *dev, const char *con_id); 181 struct pwm_device *of_pwm_get(struct device_node *np, const char *con_id); 182 void pwm_put(struct pwm_device *pwm); 183 184 struct pwm_device *devm_pwm_get(struct device *dev, const char *con_id); 185 struct pwm_device *devm_of_pwm_get(struct device *dev, struct device_node *np, 186 const char *con_id); 187 void devm_pwm_put(struct device *dev, struct pwm_device *pwm); 188 189 bool pwm_can_sleep(struct pwm_device *pwm); 190 #else 191 static inline int pwm_set_chip_data(struct pwm_device *pwm, void *data) 192 { 193 return -EINVAL; 194 } 195 196 static inline void *pwm_get_chip_data(struct pwm_device *pwm) 197 { 198 return NULL; 199 } 200 201 static inline int pwmchip_add(struct pwm_chip *chip) 202 { 203 return -EINVAL; 204 } 205 206 static inline int pwmchip_remove(struct pwm_chip *chip) 207 { 208 return -EINVAL; 209 } 210 211 static inline struct pwm_device *pwm_request_from_chip(struct pwm_chip *chip, 212 unsigned int index, 213 const char *label) 214 { 215 return ERR_PTR(-ENODEV); 216 } 217 218 static inline struct pwm_device *pwm_get(struct device *dev, 219 const char *consumer) 220 { 221 return ERR_PTR(-ENODEV); 222 } 223 224 static inline struct pwm_device *of_pwm_get(struct device_node *np, 225 const char *con_id) 226 { 227 return ERR_PTR(-ENODEV); 228 } 229 230 static inline void pwm_put(struct pwm_device *pwm) 231 { 232 } 233 234 static inline struct pwm_device *devm_pwm_get(struct device *dev, 235 const char *consumer) 236 { 237 return ERR_PTR(-ENODEV); 238 } 239 240 static inline struct pwm_device *devm_of_pwm_get(struct device *dev, 241 struct device_node *np, 242 const char *con_id) 243 { 244 return ERR_PTR(-ENODEV); 245 } 246 247 static inline void devm_pwm_put(struct device *dev, struct pwm_device *pwm) 248 { 249 } 250 251 static inline bool pwm_can_sleep(struct pwm_device *pwm) 252 { 253 return false; 254 } 255 #endif 256 257 struct pwm_lookup { 258 struct list_head list; 259 const char *provider; 260 unsigned int index; 261 const char *dev_id; 262 const char *con_id; 263 }; 264 265 #define PWM_LOOKUP(_provider, _index, _dev_id, _con_id) \ 266 { \ 267 .provider = _provider, \ 268 .index = _index, \ 269 .dev_id = _dev_id, \ 270 .con_id = _con_id, \ 271 } 272 273 #if IS_ENABLED(CONFIG_PWM) 274 void pwm_add_table(struct pwm_lookup *table, size_t num); 275 #else 276 static inline void pwm_add_table(struct pwm_lookup *table, size_t num) 277 { 278 } 279 #endif 280 281 #endif /* __LINUX_PWM_H */ 282