#ifndef __LINUX_PWM_H #define __LINUX_PWM_H #include #include struct pwm_device; struct seq_file; #if IS_ENABLED(CONFIG_PWM) /* * pwm_request - request a PWM device */ struct pwm_device *pwm_request(int pwm_id, const char *label); /* * pwm_free - free a PWM device */ void pwm_free(struct pwm_device *pwm); /* * pwm_config - change a PWM device configuration */ int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns); /* * pwm_enable - start a PWM output toggling */ int pwm_enable(struct pwm_device *pwm); /* * pwm_disable - stop a PWM output toggling */ void pwm_disable(struct pwm_device *pwm); #else static inline struct pwm_device *pwm_request(int pwm_id, const char *label) { return ERR_PTR(-ENODEV); } static inline void pwm_free(struct pwm_device *pwm) { } static inline int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns) { return -EINVAL; } static inline int pwm_enable(struct pwm_device *pwm) { return -EINVAL; } static inline void pwm_disable(struct pwm_device *pwm) { } #endif struct pwm_chip; /** * enum pwm_polarity - polarity of a PWM signal * @PWM_POLARITY_NORMAL: a high signal for the duration of the duty- * cycle, followed by a low signal for the remainder of the pulse * period * @PWM_POLARITY_INVERSED: a low signal for the duration of the duty- * cycle, followed by a high signal for the remainder of the pulse * period */ enum pwm_polarity { PWM_POLARITY_NORMAL, PWM_POLARITY_INVERSED, }; enum { PWMF_REQUESTED = 1 << 0, PWMF_ENABLED = 1 << 1, PWMF_EXPORTED = 1 << 2, }; struct pwm_device { const char *label; unsigned long flags; unsigned int hwpwm; unsigned int pwm; struct pwm_chip *chip; void *chip_data; unsigned int period; /* in nanoseconds */ unsigned int duty_cycle; /* in nanoseconds */ enum pwm_polarity polarity; }; static inline void pwm_set_period(struct pwm_device *pwm, unsigned int period) { if (pwm) pwm->period = period; } static inline unsigned int pwm_get_period(struct pwm_device *pwm) { return pwm ? pwm->period : 0; } static inline void pwm_set_duty_cycle(struct pwm_device *pwm, unsigned int duty) { if (pwm) pwm->duty_cycle = duty; } static inline unsigned int pwm_get_duty_cycle(struct pwm_device *pwm) { return pwm ? pwm->duty_cycle : 0; } /* * pwm_set_polarity - configure the polarity of a PWM signal */ int pwm_set_polarity(struct pwm_device *pwm, enum pwm_polarity polarity); /** * struct pwm_ops - PWM controller operations * @request: optional hook for requesting a PWM * @free: optional hook for freeing a PWM * @config: configure duty cycles and period length for this PWM * @set_polarity: configure the polarity of this PWM * @enable: enable PWM output toggling * @disable: disable PWM output toggling * @dbg_show: optional routine to show contents in debugfs * @owner: helps prevent removal of modules exporting active PWMs */ struct pwm_ops { int (*request)(struct pwm_chip *chip, struct pwm_device *pwm); void (*free)(struct pwm_chip *chip, struct pwm_device *pwm); int (*config)(struct pwm_chip *chip, struct pwm_device *pwm, int duty_ns, int period_ns); int (*set_polarity)(struct pwm_chip *chip, struct pwm_device *pwm, enum pwm_polarity polarity); int (*enable)(struct pwm_chip *chip, struct pwm_device *pwm); void (*disable)(struct pwm_chip *chip, struct pwm_device *pwm); #ifdef CONFIG_DEBUG_FS void (*dbg_show)(struct pwm_chip *chip, struct seq_file *s); #endif struct module *owner; }; /** * struct pwm_chip - abstract a PWM controller * @dev: device providing the PWMs * @list: list node for internal use * @ops: callbacks for this PWM controller * @base: number of first PWM controlled by this chip * @npwm: number of PWMs controlled by this chip * @pwms: array of PWM devices allocated by the framework * @can_sleep: must be true if the .config(), .enable() or .disable() * operations may sleep */ struct pwm_chip { struct device *dev; struct list_head list; const struct pwm_ops *ops; int base; unsigned int npwm; struct pwm_device *pwms; struct pwm_device * (*of_xlate)(struct pwm_chip *pc, const struct of_phandle_args *args); unsigned int of_pwm_n_cells; bool can_sleep; }; #if IS_ENABLED(CONFIG_PWM) int pwm_set_chip_data(struct pwm_device *pwm, void *data); void *pwm_get_chip_data(struct pwm_device *pwm); int pwmchip_add(struct pwm_chip *chip); int pwmchip_remove(struct pwm_chip *chip); struct pwm_device *pwm_request_from_chip(struct pwm_chip *chip, unsigned int index, const char *label); struct pwm_device *of_pwm_xlate_with_flags(struct pwm_chip *pc, const struct of_phandle_args *args); struct pwm_device *pwm_get(struct device *dev, const char *con_id); struct pwm_device *of_pwm_get(struct device_node *np, const char *con_id); void pwm_put(struct pwm_device *pwm); struct pwm_device *devm_pwm_get(struct device *dev, const char *con_id); struct pwm_device *devm_of_pwm_get(struct device *dev, struct device_node *np, const char *con_id); void devm_pwm_put(struct device *dev, struct pwm_device *pwm); bool pwm_can_sleep(struct pwm_device *pwm); #else static inline int pwm_set_chip_data(struct pwm_device *pwm, void *data) { return -EINVAL; } static inline void *pwm_get_chip_data(struct pwm_device *pwm) { return NULL; } static inline int pwmchip_add(struct pwm_chip *chip) { return -EINVAL; } static inline int pwmchip_remove(struct pwm_chip *chip) { return -EINVAL; } static inline struct pwm_device *pwm_request_from_chip(struct pwm_chip *chip, unsigned int index, const char *label) { return ERR_PTR(-ENODEV); } static inline struct pwm_device *pwm_get(struct device *dev, const char *consumer) { return ERR_PTR(-ENODEV); } static inline struct pwm_device *of_pwm_get(struct device_node *np, const char *con_id) { return ERR_PTR(-ENODEV); } static inline void pwm_put(struct pwm_device *pwm) { } static inline struct pwm_device *devm_pwm_get(struct device *dev, const char *consumer) { return ERR_PTR(-ENODEV); } static inline struct pwm_device *devm_of_pwm_get(struct device *dev, struct device_node *np, const char *con_id) { return ERR_PTR(-ENODEV); } static inline void devm_pwm_put(struct device *dev, struct pwm_device *pwm) { } static inline bool pwm_can_sleep(struct pwm_device *pwm) { return false; } #endif struct pwm_lookup { struct list_head list; const char *provider; unsigned int index; const char *dev_id; const char *con_id; unsigned int period; enum pwm_polarity polarity; }; #define PWM_LOOKUP(_provider, _index, _dev_id, _con_id, _period, _polarity) \ { \ .provider = _provider, \ .index = _index, \ .dev_id = _dev_id, \ .con_id = _con_id, \ .period = _period, \ .polarity = _polarity \ } #if IS_ENABLED(CONFIG_PWM) void pwm_add_table(struct pwm_lookup *table, size_t num); #else static inline void pwm_add_table(struct pwm_lookup *table, size_t num) { } #endif #ifdef CONFIG_PWM_SYSFS void pwmchip_sysfs_export(struct pwm_chip *chip); void pwmchip_sysfs_unexport(struct pwm_chip *chip); #else static inline void pwmchip_sysfs_export(struct pwm_chip *chip) { } static inline void pwmchip_sysfs_unexport(struct pwm_chip *chip) { } #endif /* CONFIG_PWM_SYSFS */ #endif /* __LINUX_PWM_H */