linux-imx

/* linux/drivers/hwmon/s3c-hwmon.c

 *

 * Copyright (C) 2005, 2008, 2009 Simtec Electronics

 *  http://armlinux.simtec.co.uk/

 *  Ben Dooks <ben@simtec.co.uk>

 *

 * S3C24XX/S3C64XX ADC hwmon support

 *

 * This program is free software; you can redistribute it 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

*/

​

#include <linux/module.h>

#include <linux/slab.h>

#include <linux/io.h>

#include <linux/init.h>

#include <linux/err.h>

#include <linux/clk.h>

#include <linux/interrupt.h>

#include <linux/platform_device.h>

​

#include <linux/hwmon.h>

#include <linux/hwmon-sysfs.h>

​

#include <plat/adc.h>

#include <linux/platform_data/hwmon-s3c.h>

​

struct s3c_hwmon_attr {

    struct sensor_device_attribute  in;

    struct sensor_device_attribute  label;

    char                in_name[12];

    char                label_name[12];

};

​

/**

 * struct s3c_hwmon - ADC hwmon client information

 * @lock: Access lock to serialise the conversions.

 * @client: The client we registered with the S3C ADC core.

 * @hwmon_dev: The hwmon device we created.

 * @attr: The holders for the channel attributes.

*/

struct s3c_hwmon {

    struct mutex        lock;

    struct s3c_adc_client   *client;

    struct device       *hwmon_dev;

​

    struct s3c_hwmon_attr   attrs[8];

};

​

/**

 * s3c_hwmon_read_ch - read a value from a given adc channel.

 * @dev: The device.

 * @hwmon: Our state.

 * @channel: The channel we're reading from.

 *

 * Read a value from the @channel with the proper locking and sleep until

 * either the read completes or we timeout awaiting the ADC core to get

 * back to us.

 */

static int s3c_hwmon_read_ch(struct device *dev,

                 struct s3c_hwmon *hwmon, int channel)

{

    int ret;

​

    ret = mutex_lock_interruptible(&hwmon->lock);

    if (ret < 0)

        return ret;

​

    dev_dbg(dev, "reading channel %d\n", channel);

​

    ret = s3c_adc_read(hwmon->client, channel);

    mutex_unlock(&hwmon->lock);

​

    return ret;

}

​

#ifdef CONFIG_SENSORS_S3C_RAW

/**

 * s3c_hwmon_show_raw - show a conversion from the raw channel number.

 * @dev: The device that the attribute belongs to.

 * @attr: The attribute being read.

 * @buf: The result buffer.