/*
 * include/linux/pwm.h
 *
 * Copyright (C) 2008 Bill Gatliff < bgat@billgatliff.com>
 *
 * This program is free software; you may redistribute and/or modify
 * it under the terms of the GNU General Public License version 2, as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
 * USA
 */
#ifndef __LINUX_PWM_H
#define __LINUX_PWM_H

enum {
	PWM_CONFIG_DUTY_TICKS = BIT(0),
	PWM_CONFIG_PERIOD_TICKS = BIT(1),
	PWM_CONFIG_POLARITY = BIT(2),
	PWM_CONFIG_START = BIT(3),
	PWM_CONFIG_STOP = BIT(4),

	PWM_CONFIG_HANDLER = BIT(5),

	PWM_CONFIG_DUTY_NS = BIT(6),
	PWM_CONFIG_DUTY_PERCENT = BIT(7),
	PWM_CONFIG_PERIOD_NS = BIT(8),
};

struct pwm_channel;
struct work_struct;

typedef int (*pwm_handler_t)(struct pwm_channel *p, void *data);
typedef void (*pwm_callback_t)(struct pwm_channel *p);

struct pwm_channel_config {
	int config_mask;
	unsigned long duty_ticks;
	unsigned long period_ticks;
	int polarity;

	pwm_handler_t handler;

	unsigned long duty_ns;
	unsigned long period_ns;
	int duty_percent;
};

struct pwm_device {
	struct list_head list;
	spinlock_t list_lock;
	struct device *dev;
	struct module *owner;
	struct pwm_channel *channels;

	const char *bus_id;
	int nchan;

	int	(*request)	(struct pwm_channel *p);
	void	(*free)		(struct pwm_channel *p);
	int	(*config)	(struct pwm_channel *p,
				 struct pwm_channel_config *c);
	int	(*config_nosleep)(struct pwm_channel *p,
				  struct pwm_channel_config *c);
	int	(*synchronize)	(struct pwm_channel *p,
				 struct pwm_channel *to_p);
	int	(*unsynchronize)(struct pwm_channel *p,
				 struct pwm_channel *from_p);
	int	(*set_callback)	(struct pwm_channel *p,
				 pwm_callback_t callback);
};

int pwm_register(struct pwm_device *pwm);
int pwm_unregister(struct pwm_device *pwm);

enum {
	FLAG_REQUESTED = 0,
	FLAG_STOP = 1,
};

struct pwm_channel {
	struct list_head list;
	struct pwm_device *pwm;
	const char *requester;
	pid_t pid;
	int chan;
	unsigned long flags;
	unsigned long tick_hz;

	spinlock_t lock;
	struct completion complete;

	pwm_callback_t callback;

	struct work_struct handler_work;
	pwm_handler_t handler;
	void *handler_data;

	int active_high;
	unsigned long period_ticks;
	unsigned long duty_ticks;
};

struct gpio_pwm_platform_data {
	int gpio;
};

struct pwm_channel *
pwm_request(const char *bus_id, int chan,
	    const char *requester);

void pwm_free(struct pwm_channel *pwm);

int pwm_config_nosleep(struct pwm_channel *pwm,
		       struct pwm_channel_config *c);

int pwm_config(struct pwm_channel *pwm,
	       struct pwm_channel_config *c);

unsigned long pwm_ns_to_ticks(struct pwm_channel *pwm,
			      unsigned long nsecs);

unsigned long pwm_ticks_to_ns(struct pwm_channel *pwm,
			      unsigned long ticks);

int pwm_set_period_ns(struct pwm_channel *pwm,
		      unsigned long period_ns);

unsigned long int pwm_get_period_ns(struct pwm_channel *pwm);

int pwm_set_duty_ns(struct pwm_channel *pwm,
		    unsigned long duty_ns);

int pwm_set_duty_percent(struct pwm_channel *pwm,
			 int percent);

unsigned long pwm_get_duty_ns(struct pwm_channel *pwm);

int pwm_set_polarity(struct pwm_channel *pwm,
		     int active_high);

int pwm_start(struct pwm_channel *pwm);

int pwm_stop(struct pwm_channel *pwm);

int pwm_set_handler(struct pwm_channel *pwm,
		    pwm_handler_t handler,
		    void *data);

int pwm_synchronize(struct pwm_channel *p,
		    struct pwm_channel *to_p);


int pwm_unsynchronize(struct pwm_channel *p,
		      struct pwm_channel *from_p);


#endif /* __LINUX_PWM_H */