linux-imx

/*

 *  Copyright (C) 2010, Lars-Peter Clausen <lars@metafoo.de>

 *  JZ4740 platform PWM support

 *

 *  This program is free software; you can redistribute it and/or modify it

 *  under  the terms of the GNU General  Public License as published by the

 *  Free Software Foundation;  either version 2 of the License, or (at your

 *  option) any later version.

 *

 *  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.,

 *  675 Mass Ave, Cambridge, MA 02139, USA.

 *

 */

​

#include <linux/clk.h>

#include <linux/err.h>

#include <linux/gpio.h>

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/of_device.h>

#include <linux/platform_device.h>

#include <linux/pwm.h>

​

#include <asm/mach-jz4740/timer.h>

​

#define NUM_PWM 8

​

struct jz4740_pwm_chip {

    struct pwm_chip chip;

    struct clk *clk;

};

​

static inline struct jz4740_pwm_chip *to_jz4740(struct pwm_chip *chip)

{

    return container_of(chip, struct jz4740_pwm_chip, chip);

}

​

static int jz4740_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)

{

    /*

     * Timers 0 and 1 are used for system tasks, so they are unavailable

     * for use as PWMs.

     */

    if (pwm->hwpwm < 2)

        return -EBUSY;

​

    jz4740_timer_start(pwm->hwpwm);

​

    return 0;

}

​

static void jz4740_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)

{

    jz4740_timer_set_ctrl(pwm->hwpwm, 0);

​

    jz4740_timer_stop(pwm->hwpwm);

}

​

static int jz4740_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)

{

    uint32_t ctrl = jz4740_timer_get_ctrl(pwm->pwm);

​