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	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 /* SPDX-License-Identifier: GPL-2.0 */
 #ifndef __LINUX_PWM_H
 #define __LINUX_PWM_H
 
 #include <linux/err.h>
 #include <linux/mutex.h>
 #include <linux/of.h>
 
 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,
 };
 
 /**
  * struct pwm_args - board-dependent PWM arguments
  * @period: reference period
  * @polarity: reference polarity
  *
  * This structure describes board-dependent arguments attached to a PWM
  * device. These arguments are usually retrieved from the PWM lookup table or
  * device tree.
  *
  * Do not confuse this with the PWM state: PWM arguments represent the initial
  * configuration that users want to use on this PWM device rather than the
  * current PWM hardware state.
  */
 struct pwm_args {
     u64 period;
     enum pwm_polarity polarity;
 };
 
 enum {
     PWMF_REQUESTED = 1 << 0,
     PWMF_EXPORTED = 1 << 1,
 };
 
 /*
  * struct pwm_state - state of a PWM channel
  * @period: PWM period (in nanoseconds)
  * @duty_cycle: PWM duty cycle (in nanoseconds)
  * @polarity: PWM polarity
  * @enabled: PWM enabled status
  * @usage_power: If set, the PWM driver is only required to maintain the power
  *               output but has more freedom regarding signal form.
  *               If supported, the signal can be optimized, for example to
  *               improve EMI by phase shifting individual channels.
  */
 struct pwm_state {
     u64 period;
     u64 duty_cycle;
     enum pwm_polarity polarity;
     bool enabled;
     bool usage_power;
 };
 
 /**
  * struct pwm_device - PWM channel object
  * @label: name of the PWM device
  * @flags: flags associated with the PWM device
  * @hwpwm: per-chip relative index of the PWM device
  * @pwm: global index of the PWM device
  * @chip: PWM chip providing this PWM device
  * @chip_data: chip-private data associated with the PWM device
  * @args: PWM arguments
  * @state: last applied state
  * @last: last implemented state (for PWM_DEBUG)
  */
 struct pwm_device {
     const char *label;
     unsigned long flags;
     unsigned int hwpwm;
     unsigned int pwm;
     struct pwm_chip *chip;
     void *chip_data;
 
     struct pwm_args args;
     struct pwm_state state;
     struct pwm_state last;
 };
 
 /**
  * pwm_get_state() - retrieve the current PWM state
  * @pwm: PWM device
  * @state: state to fill with the current PWM state
  *
  * The returned PWM state represents the state that was applied by a previous call to
  * pwm_apply_state(). Drivers may have to slightly tweak that state before programming it to
  * hardware. If pwm_apply_state() was never called, this returns either the current hardware
  * state (if supported) or the default settings.
  */
 static inline void pwm_get_state(const struct pwm_device *pwm,
                  struct pwm_state *state)
 {
     *state = pwm->state;
 }
 
 static inline bool pwm_is_enabled(const struct pwm_device *pwm)
 {
     struct pwm_state state;
 
     pwm_get_state(pwm, &state);
 
     return state.enabled;
 }
 
 static inline void pwm_set_period(struct pwm_device *pwm, u64 period)
 {
     if (pwm)
         pwm->state.period = period;
 }
 
 static inline u64 pwm_get_period(const struct pwm_device *pwm)
 {
     struct pwm_state state;
 
     pwm_get_state(pwm, &state);
 
     return state.period;
 }
 
 static inline void pwm_set_duty_cycle(struct pwm_device *pwm, unsigned int duty)
 {
     if (pwm)
         pwm->state.duty_cycle = duty;
 }
 
 static inline u64 pwm_get_duty_cycle(const struct pwm_device *pwm)
 {
     struct pwm_state state;
 
     pwm_get_state(pwm, &state);
 
     return state.duty_cycle;
 }
 
 static inline enum pwm_polarity pwm_get_polarity(const struct pwm_device *pwm)
 {
     struct pwm_state state;
 
     pwm_get_state(pwm, &state);
 
     return state.polarity;
 }
 
 static inline void pwm_get_args(const struct pwm_device *pwm,
                 struct pwm_args *args)
 {
     *args = pwm->args;
 }
 
 /**
  * pwm_init_state() - prepare a new state to be applied with pwm_apply_state()
  * @pwm: PWM device
  * @state: state to fill with the prepared PWM state
  *
  * This functions prepares a state that can later be tweaked and applied
  * to the PWM device with pwm_apply_state(). This is a convenient function
  * that first retrieves the current PWM state and the replaces the period
  * and polarity fields with the reference values defined in pwm->args.
  * Once the function returns, you can adjust the ->enabled and ->duty_cycle
  * fields according to your needs before calling pwm_apply_state().
  *
  * ->duty_cycle is initially set to zero to avoid cases where the current
  * ->duty_cycle value exceed the pwm_args->period one, which would trigger
  * an error if the user calls pwm_apply_state() without adjusting ->duty_cycle
  * first.
  */
 static inline void pwm_init_state(const struct pwm_device *pwm,
                   struct pwm_state *state)
 {
     struct pwm_args args;
 
     /* First get the current state. */
     pwm_get_state(pwm, state);
 
     /* Then fill it with the reference config */
     pwm_get_args(pwm, &args);
 
     state->period = args.period;
     state->polarity = args.polarity;
     state->duty_cycle = 0;
     state->usage_power = false;
 }
 
 /**
  * pwm_get_relative_duty_cycle() - Get a relative duty cycle value
  * @state: PWM state to extract the duty cycle from
  * @scale: target scale of the relative duty cycle
  *
  * This functions converts the absolute duty cycle stored in @state (expressed
  * in nanosecond) into a value relative to the period.
  *
  * For example if you want to get the duty_cycle expressed in percent, call:
  *
  * pwm_get_state(pwm, &state);
  * duty = pwm_get_relative_duty_cycle(&state, 100);
  */
 static inline unsigned int
 pwm_get_relative_duty_cycle(const struct pwm_state *state, unsigned int scale)
 {
     if (!state->period)
         return 0;
 
     return DIV_ROUND_CLOSEST_ULL((u64)state->duty_cycle * scale,
                      state->period);
 }
 
 /**
  * pwm_set_relative_duty_cycle() - Set a relative duty cycle value
  * @state: PWM state to fill
  * @duty_cycle: relative duty cycle value
  * @scale: scale in which @duty_cycle is expressed
  *
  * This functions converts a relative into an absolute duty cycle (expressed
  * in nanoseconds), and puts the result in state->duty_cycle.
  *
  * For example if you want to configure a 50% duty cycle, call:
  *
  * pwm_init_state(pwm, &state);
  * pwm_set_relative_duty_cycle(&state, 50, 100);
  * pwm_apply_state(pwm, &state);
  *
  * This functions returns -EINVAL if @duty_cycle and/or @scale are
  * inconsistent (@scale == 0 or @duty_cycle > @scale).
  */
 static inline int
 pwm_set_relative_duty_cycle(struct pwm_state *state, unsigned int duty_cycle,
                 unsigned int scale)
 {
     if (!scale || duty_cycle > scale)
         return -EINVAL;
 
     state->duty_cycle = DIV_ROUND_CLOSEST_ULL((u64)duty_cycle *
                           state->period,
                           scale);
 
     return 0;
 }
 
 /**
  * struct pwm_capture - PWM capture data
  * @period: period of the PWM signal (in nanoseconds)
  * @duty_cycle: duty cycle of the PWM signal (in nanoseconds)
  */
 struct pwm_capture {
     unsigned int period;
     unsigned int duty_cycle;
 };
 
 /**
  * struct pwm_ops - PWM controller operations
  * @request: optional hook for requesting a PWM
  * @free: optional hook for freeing a PWM
  * @capture: capture and report PWM signal
  * @apply: atomically apply a new PWM config
  * @get_state: get the current PWM state. This function is only
  *         called once per PWM device when the PWM chip is
  *         registered.
  * @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 (*capture)(struct pwm_chip *chip, struct pwm_device *pwm,
                struct pwm_capture *result, unsigned long timeout);
     int (*apply)(struct pwm_chip *chip, struct pwm_device *pwm,
              const struct pwm_state *state);
     void (*get_state)(struct pwm_chip *chip, struct pwm_device *pwm,
               struct pwm_state *state);
     struct module *owner;
 };
 
 /**
  * struct pwm_chip - abstract a PWM controller
  * @dev: device providing the PWMs
  * @ops: callbacks for this PWM controller
  * @base: number of first PWM controlled by this chip
  * @npwm: number of PWMs controlled by this chip
  * @of_xlate: request a PWM device given a device tree PWM specifier
  * @of_pwm_n_cells: number of cells expected in the device tree PWM specifier
  * @list: list node for internal use
  * @pwms: array of PWM devices allocated by the framework
  */
 struct pwm_chip {
     struct device *dev;
     const struct pwm_ops *ops;
     int base;
     unsigned int npwm;
 
     struct pwm_device * (*of_xlate)(struct pwm_chip *pc,
                     const struct of_phandle_args *args);
     unsigned int of_pwm_n_cells;
 
     /* only used internally by the PWM framework */
     struct list_head list;
     struct pwm_device *pwms;
 };
 
 #if IS_ENABLED(CONFIG_PWM)
 /* PWM user APIs */
 struct pwm_device *pwm_request(int pwm_id, const char *label);
 void pwm_free(struct pwm_device *pwm);
 int pwm_apply_state(struct pwm_device *pwm, const struct pwm_state *state);
 int pwm_adjust_config(struct pwm_device *pwm);
 
 /**
  * pwm_config() - change a PWM device configuration
  * @pwm: PWM device
  * @duty_ns: "on" time (in nanoseconds)
  * @period_ns: duration (in nanoseconds) of one cycle
  *
  * Returns: 0 on success or a negative error code on failure.
  */
 static inline int pwm_config(struct pwm_device *pwm, int duty_ns,
                  int period_ns)
 {
     struct pwm_state state;
 
     if (!pwm)
         return -EINVAL;
 
     if (duty_ns < 0 || period_ns < 0)
         return -EINVAL;
 
     pwm_get_state(pwm, &state);
     if (state.duty_cycle == duty_ns && state.period == period_ns)
         return 0;
 
     state.duty_cycle = duty_ns;
     state.period = period_ns;
     return pwm_apply_state(pwm, &state);
 }
 
 /**
  * pwm_enable() - start a PWM output toggling
  * @pwm: PWM device
  *
  * Returns: 0 on success or a negative error code on failure.
  */
 static inline int pwm_enable(struct pwm_device *pwm)
 {
     struct pwm_state state;
 
     if (!pwm)
         return -EINVAL;
 
     pwm_get_state(pwm, &state);
     if (state.enabled)
         return 0;
 
     state.enabled = true;
     return pwm_apply_state(pwm, &state);
 }
 
 /**
  * pwm_disable() - stop a PWM output toggling
  * @pwm: PWM device
  */
 static inline void pwm_disable(struct pwm_device *pwm)
 {
     struct pwm_state state;
 
     if (!pwm)
         return;
 
     pwm_get_state(pwm, &state);
     if (!state.enabled)
         return;
 
     state.enabled = false;
     pwm_apply_state(pwm, &state);
 }
 
 /* PWM provider APIs */
 int pwm_capture(struct pwm_device *pwm, struct pwm_capture *result,
         unsigned long timeout);
 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);
 void pwmchip_remove(struct pwm_chip *chip);
 
 int devm_pwmchip_add(struct device *dev, 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 *of_pwm_single_xlate(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 *dev, 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);
 struct pwm_device *devm_fwnode_pwm_get(struct device *dev,
                        struct fwnode_handle *fwnode,
                        const char *con_id);
 #else
 static inline struct pwm_device *pwm_request(int pwm_id, const char *label)
 {
     might_sleep();
     return ERR_PTR(-ENODEV);
 }
 
 static inline void pwm_free(struct pwm_device *pwm)
 {
     might_sleep();
 }
 
 static inline int pwm_apply_state(struct pwm_device *pwm,
                   const struct pwm_state *state)
 {
     might_sleep();
     return -ENOTSUPP;
 }
 
 static inline int pwm_adjust_config(struct pwm_device *pwm)
 {
     return -ENOTSUPP;
 }
 
 static inline int pwm_config(struct pwm_device *pwm, int duty_ns,
                  int period_ns)
 {
     might_sleep();
     return -EINVAL;
 }
 
 static inline int pwm_capture(struct pwm_device *pwm,
                   struct pwm_capture *result,
                   unsigned long timeout)
 {
     return -EINVAL;
 }
 
 static inline int pwm_enable(struct pwm_device *pwm)
 {
     might_sleep();
     return -EINVAL;
 }
 
 static inline void pwm_disable(struct pwm_device *pwm)
 {
     might_sleep();
 }
 
 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)
 {
     might_sleep();
     return ERR_PTR(-ENODEV);
 }
 
 static inline struct pwm_device *pwm_get(struct device *dev,
                      const char *consumer)
 {
     might_sleep();
     return ERR_PTR(-ENODEV);
 }
 
 static inline struct pwm_device *of_pwm_get(struct device *dev,
                         struct device_node *np,
                         const char *con_id)
 {
     might_sleep();
     return ERR_PTR(-ENODEV);
 }
 
 static inline void pwm_put(struct pwm_device *pwm)
 {
     might_sleep();
 }
 
 static inline struct pwm_device *devm_pwm_get(struct device *dev,
                           const char *consumer)
 {
     might_sleep();
     return ERR_PTR(-ENODEV);
 }
 
 static inline struct pwm_device *devm_of_pwm_get(struct device *dev,
                          struct device_node *np,
                          const char *con_id)
 {
     might_sleep();
     return ERR_PTR(-ENODEV);
 }
 
 static inline struct pwm_device *
 devm_fwnode_pwm_get(struct device *dev, struct fwnode_handle *fwnode,
             const char *con_id)
 {
     might_sleep();
     return ERR_PTR(-ENODEV);
 }
 #endif
 
 static inline void pwm_apply_args(struct pwm_device *pwm)
 {
     struct pwm_state state = { };
 
     /*
      * PWM users calling pwm_apply_args() expect to have a fresh config
      * where the polarity and period are set according to pwm_args info.
      * The problem is, polarity can only be changed when the PWM is
      * disabled.
      *
      * PWM drivers supporting hardware readout may declare the PWM device
      * as enabled, and prevent polarity setting, which changes from the
      * existing behavior, where all PWM devices are declared as disabled
      * at startup (even if they are actually enabled), thus authorizing
      * polarity setting.
      *
      * To fulfill this requirement, we apply a new state which disables
      * the PWM device and set the reference period and polarity config.
      *
      * Note that PWM users requiring a smooth handover between the
      * bootloader and the kernel (like critical regulators controlled by
      * PWM devices) will have to switch to the atomic API and avoid calling
      * pwm_apply_args().
      */
 
     state.enabled = false;
     state.polarity = pwm->args.polarity;
     state.period = pwm->args.period;
     state.usage_power = false;
 
     pwm_apply_state(pwm, &state);
 }
 
 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;
     const char *module; /* optional, may be NULL */
 };
 
 #define PWM_LOOKUP_WITH_MODULE(_provider, _index, _dev_id, _con_id, \
                    _period, _polarity, _module)     \
     {                               \
         .provider = _provider,                  \
         .index = _index,                    \
         .dev_id = _dev_id,                  \
         .con_id = _con_id,                  \
         .period = _period,                  \
         .polarity = _polarity,                  \
         .module = _module,                  \
     }
 
 #define PWM_LOOKUP(_provider, _index, _dev_id, _con_id, _period, _polarity) \
     PWM_LOOKUP_WITH_MODULE(_provider, _index, _dev_id, _con_id, _period, \
                    _polarity, NULL)
 
 #if IS_ENABLED(CONFIG_PWM)
 void pwm_add_table(struct pwm_lookup *table, size_t num);
 void pwm_remove_table(struct pwm_lookup *table, size_t num);
 #else
 static inline void pwm_add_table(struct pwm_lookup *table, size_t num)
 {
 }
 
 static inline void pwm_remove_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 */

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