_pwm.c

/*
 * File      : _pwm.c
 * This file is part of RT-Thread RTOS
 * COPYRIGHT (C) 2018, RT-Thread Development Team
 *
 *  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.
 *
 *  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.,
 *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Change Logs:
 * Date           Author       Notes
 * 2018-05-07     aozima       the first version
 */

#include <string.h>

#include <rtthread.h>
#include <rtdevice.h>


static rt_err_t _pwm_control(rt_device_t dev, int cmd, void *args)
{
    rt_err_t result = RT_EOK;
    struct rt_device_pwm *pwm = (struct rt_device_pwm *)dev;

    if (pwm->ops->control)
    {
        result = pwm->ops->control(pwm, cmd, args);
    }

    return result;
}


/*
pos: channel
void *buffer: rt_uint32_t pulse[size]
size : number of pulse, only set to sizeof(rt_uint32_t).
*/
static rt_size_t _pwm_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
{
    rt_err_t result = RT_EOK;
    struct rt_device_pwm *pwm = (struct rt_device_pwm *)dev;
    rt_uint32_t *pulse = (rt_uint32_t *)buffer;
    struct rt_pwm_configuration configuration = {0};

    configuration.channel = pos;

    if (pwm->ops->control)
    {
        result = pwm->ops->control(pwm, PWM_CMD_GET,  &configuration);
        if (result != RT_EOK)
        {
            return 0;
        }

        *pulse = configuration.pulse;
    }

    return size;
}

/*
pos: channel
void *buffer: rt_uint32_t pulse[size]
size : number of pulse, only set to sizeof(rt_uint32_t).
*/
static rt_size_t _pwm_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
{
    rt_err_t result = RT_EOK;
    struct rt_device_pwm *pwm = (struct rt_device_pwm *)dev;
    rt_uint32_t *pulse = (rt_uint32_t *)buffer;
    struct rt_pwm_configuration configuration = {0};

    configuration.channel = pos;

    if (pwm->ops->control)
    {
        result = pwm->ops->control(pwm, PWM_CMD_GET, &configuration);
        if (result != RT_EOK)
        {
            return 0;
        }

        configuration.pulse = *pulse;

        result = pwm->ops->control(pwm, PWM_CMD_SET, &configuration);
        if (result != RT_EOK)
        {
            return 0;
        }

    }

    return size;
}

rt_err_t rt_device_pwm_register(struct rt_device_pwm *device, const char *name, const struct rt_pwm_ops *ops, const void *user_data)
{
    rt_err_t result = RT_EOK;

    memset(device, 0, sizeof(struct rt_device_pwm));

    device->parent.type         = RT_Device_Class_Miscellaneous;

    device->parent.init         = RT_NULL;
    device->parent.open         = RT_NULL;
    device->parent.close        = RT_NULL;
    device->parent.read         = _pwm_read;
    device->parent.write        = _pwm_write;
    device->parent.control      = _pwm_control;

    device->ops                 = ops;
    device->parent.user_data    = (void *)user_data;

    result = rt_device_register(&device->parent, name, RT_DEVICE_FLAG_RDWR);

    return result;
}

rt_err_t rt_pwm_enable(int channel)
{
    rt_err_t result = RT_EOK;
    struct rt_device *device = rt_device_find("pwm");
    struct rt_pwm_configuration configuration = {0};

    if (!device)
    {
        return -RT_EIO;
    }

    configuration.channel = channel;
    result = rt_device_control(device, PWM_CMD_ENABLE, &configuration);

    return result;
}

rt_err_t rt_pwm_set(int channel, rt_uint32_t period, rt_uint32_t pulse)
{
    rt_err_t result = RT_EOK;
    struct rt_device *device = rt_device_find("pwm");
    struct rt_pwm_configuration configuration = {0};

    if (!device)
    {
        return -RT_EIO;
    }

    configuration.channel = channel;
    configuration.period = period;
    configuration.pulse = pulse;
    result = rt_device_control(device, PWM_CMD_SET, &configuration);

    return result;
}


#ifdef RT_USING_FINSH
#include <finsh.h>

FINSH_FUNCTION_EXPORT_ALIAS(rt_pwm_enable, pwm_enable, enable pwm by channel.);
FINSH_FUNCTION_EXPORT_ALIAS(rt_pwm_set, pwm_set, set pwm.);

#ifdef FINSH_USING_MSH
static int pwm_enable(int argc, char **argv)
{
    int result = 0;

    if (argc != 2)
    {
        rt_kprintf("Usage: pwm_enable 1\n");
        result = -RT_ERROR;
        goto _exit;
    }

    result = rt_pwm_enable(atoi(argv[1]));

_exit:
    return result;
}
MSH_CMD_EXPORT(pwm_enable, pwm_enable 1);

static int pwm_set(int argc, char **argv)
{
    int result = 0;

    if (argc != 4)
    {
        rt_kprintf("Usage: pwm_set 1 100 50\n");
        result = -RT_ERROR;
        goto _exit;
    }

    result = rt_pwm_set(atoi(argv[1]), atoi(argv[2]), atoi(argv[3]));

_exit:
    return result;
}
MSH_CMD_EXPORT(pwm_set, pwm_set 1 100 50);

#endif /* FINSH_USING_MSH */


#endif /* RT_USING_FINSH */