1#ifndef __LINUX_PWM_H 2#define __LINUX_PWM_H 3 4#include <linux/err.h> 5#include <linux/of.h> 6 7struct pwm_device; 8struct seq_file; 9 10#if IS_ENABLED(CONFIG_PWM) 11/* 12 * pwm_request - request a PWM device 13 */ 14struct pwm_device *pwm_request(int pwm_id, const char *label); 15 16/* 17 * pwm_free - free a PWM device 18 */ 19void pwm_free(struct pwm_device *pwm); 20 21/* 22 * pwm_config - change a PWM device configuration 23 */ 24int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns); 25 26/* 27 * pwm_enable - start a PWM output toggling 28 */ 29int pwm_enable(struct pwm_device *pwm); 30 31/* 32 * pwm_disable - stop a PWM output toggling 33 */ 34void pwm_disable(struct pwm_device *pwm); 35#else 36static inline struct pwm_device *pwm_request(int pwm_id, const char *label) 37{ 38 return ERR_PTR(-ENODEV); 39} 40 41static inline void pwm_free(struct pwm_device *pwm) 42{ 43} 44 45static inline int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns) 46{ 47 return -EINVAL; 48} 49 50static inline int pwm_enable(struct pwm_device *pwm) 51{ 52 return -EINVAL; 53} 54 55static inline void pwm_disable(struct pwm_device *pwm) 56{ 57} 58#endif 59 60struct 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 */ 71enum pwm_polarity { 72 PWM_POLARITY_NORMAL, 73 PWM_POLARITY_INVERSED, 74}; 75 76enum { 77 PWMF_REQUESTED = 1 << 0, 78 PWMF_ENABLED = 1 << 1, 79 PWMF_EXPORTED = 1 << 2, 80}; 81 82struct 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 95static inline void pwm_set_period(struct pwm_device *pwm, unsigned int period) 96{ 97 if (pwm) 98 pwm->period = period; 99} 100 101static inline unsigned int pwm_get_period(struct pwm_device *pwm) 102{ 103 return pwm ? pwm->period : 0; 104} 105 106static inline void pwm_set_duty_cycle(struct pwm_device *pwm, unsigned int duty) 107{ 108 if (pwm) 109 pwm->duty_cycle = duty; 110} 111 112static 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 */ 120int 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 */ 133struct 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 */ 166struct 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) 182int pwm_set_chip_data(struct pwm_device *pwm, void *data); 183void *pwm_get_chip_data(struct pwm_device *pwm); 184 185int pwmchip_add(struct pwm_chip *chip); 186int pwmchip_remove(struct pwm_chip *chip); 187struct pwm_device *pwm_request_from_chip(struct pwm_chip *chip, 188 unsigned int index, 189 const char *label); 190 191struct pwm_device *of_pwm_xlate_with_flags(struct pwm_chip *pc, 192 const struct of_phandle_args *args); 193 194struct pwm_device *pwm_get(struct device *dev, const char *con_id); 195struct pwm_device *of_pwm_get(struct device_node *np, const char *con_id); 196void pwm_put(struct pwm_device *pwm); 197 198struct pwm_device *devm_pwm_get(struct device *dev, const char *con_id); 199struct pwm_device *devm_of_pwm_get(struct device *dev, struct device_node *np, 200 const char *con_id); 201void devm_pwm_put(struct device *dev, struct pwm_device *pwm); 202 203bool pwm_can_sleep(struct pwm_device *pwm); 204#else 205static inline int pwm_set_chip_data(struct pwm_device *pwm, void *data) 206{ 207 return -EINVAL; 208} 209 210static inline void *pwm_get_chip_data(struct pwm_device *pwm) 211{ 212 return NULL; 213} 214 215static inline int pwmchip_add(struct pwm_chip *chip) 216{ 217 return -EINVAL; 218} 219 220static inline int pwmchip_remove(struct pwm_chip *chip) 221{ 222 return -EINVAL; 223} 224 225static inline struct pwm_device *pwm_request_from_chip(struct pwm_chip *chip, 226 unsigned int index, 227 const char *label) 228{ 229 return ERR_PTR(-ENODEV); 230} 231 232static inline struct pwm_device *pwm_get(struct device *dev, 233 const char *consumer) 234{ 235 return ERR_PTR(-ENODEV); 236} 237 238static inline struct pwm_device *of_pwm_get(struct device_node *np, 239 const char *con_id) 240{ 241 return ERR_PTR(-ENODEV); 242} 243 244static inline void pwm_put(struct pwm_device *pwm) 245{ 246} 247 248static inline struct pwm_device *devm_pwm_get(struct device *dev, 249 const char *consumer) 250{ 251 return ERR_PTR(-ENODEV); 252} 253 254static inline struct pwm_device *devm_of_pwm_get(struct device *dev, 255 struct device_node *np, 256 const char *con_id) 257{ 258 return ERR_PTR(-ENODEV); 259} 260 261static inline void devm_pwm_put(struct device *dev, struct pwm_device *pwm) 262{ 263} 264 265static inline bool pwm_can_sleep(struct pwm_device *pwm) 266{ 267 return false; 268} 269#endif 270 271struct pwm_lookup { 272 struct list_head list; 273 const char *provider; 274 unsigned int index; 275 const char *dev_id; 276 const char *con_id; 277 unsigned int period; 278 enum pwm_polarity polarity; 279}; 280 281#define PWM_LOOKUP(_provider, _index, _dev_id, _con_id, _period, _polarity) \ 282 { \ 283 .provider = _provider, \ 284 .index = _index, \ 285 .dev_id = _dev_id, \ 286 .con_id = _con_id, \ 287 .period = _period, \ 288 .polarity = _polarity \ 289 } 290 291#if IS_ENABLED(CONFIG_PWM) 292void pwm_add_table(struct pwm_lookup *table, size_t num); 293#else 294static inline void pwm_add_table(struct pwm_lookup *table, size_t num) 295{ 296} 297#endif 298 299#ifdef CONFIG_PWM_SYSFS 300void pwmchip_sysfs_export(struct pwm_chip *chip); 301void pwmchip_sysfs_unexport(struct pwm_chip *chip); 302#else 303static inline void pwmchip_sysfs_export(struct pwm_chip *chip) 304{ 305} 306 307static inline void pwmchip_sysfs_unexport(struct pwm_chip *chip) 308{ 309} 310#endif /* CONFIG_PWM_SYSFS */ 311 312#endif /* __LINUX_PWM_H */ 313