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/*
* Driver for ADI Direct Digital Synthesis ad9850
*
* Copyright (c) 2010-2010 Analog Devices Inc.
*
* 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.
*
*/
#include <linux/types.h>
#include <linux/mutex.h>
#include <linux/device.h>
#include <linux/spi/spi.h>
#include <linux/slab.h>
#include <linux/sysfs.h>
#include <linux/module.h>
#include "../iio.h"
#include "../sysfs.h"
#define DRV_NAME "ad9850"
#define value_mask (u16)0xf000
#define addr_shift 12
/* Register format: 4 bits addr + 12 bits value */
struct ad9850_config {
u8 control[5];
};
struct ad9850_state {
struct mutex lock;
struct spi_device *sdev;
};
static ssize_t ad9850_set_parameter(struct device *dev,
struct device_attribute *attr,
const char *buf,
size_t len)
{
struct spi_message msg;
struct spi_transfer xfer;
int ret;
struct ad9850_config *config = (struct ad9850_config *)buf;
struct iio_dev *idev = dev_get_drvdata(dev);
struct ad9850_state *st = iio_priv(idev);
xfer.len = len;
xfer.tx_buf = config;
mutex_lock(&st->lock);
spi_message_init(&msg);
spi_message_add_tail(&xfer, &msg);
ret = spi_sync(st->sdev, &msg);
if (ret)
goto error_ret;
error_ret:
mutex_unlock(&st->lock);
return ret ? ret : len;
}
static IIO_DEVICE_ATTR(dds, S_IWUSR, NULL, ad9850_set_parameter, 0);
static struct attribute *ad9850_attributes[] = {
&iio_dev_attr_dds.dev_attr.attr,
NULL,
};
static const struct attribute_group ad9850_attribute_group = {
.attrs = ad9850_attributes,
};
static const struct iio_info ad9850_info = {
.attrs = &ad9850_attribute_group,
.driver_module = THIS_MODULE,
};
static int __devinit ad9850_probe(struct spi_device *spi)
{
struct ad9850_state *st;
struct iio_dev *idev;
int ret = 0;
idev = iio_allocate_device(sizeof(*st));
if (idev == NULL) {
ret = -ENOMEM;
goto error_ret;
}
spi_set_drvdata(spi, idev);
st = iio_priv(idev);
mutex_init(&st->lock);
st->sdev = spi;
idev->dev.parent = &spi->dev;
idev->info = &ad9850_info;
idev->modes = INDIO_DIRECT_MODE;
ret = iio_device_register(idev);
if (ret)
goto error_free_dev;
spi->max_speed_hz = 2000000;
spi->mode = SPI_MODE_3;
spi->bits_per_word = 16;
spi_setup(spi);
return 0;
error_free_dev:
iio_free_device(idev);
error_ret:
return ret;
}
static int __devexit ad9850_remove(struct spi_device *spi)
{
iio_device_unregister(spi_get_drvdata(spi));
return 0;
}
static struct spi_driver ad9850_driver = {
.driver = {
.name = DRV_NAME,
.owner = THIS_MODULE,
},
.probe = ad9850_probe,
.remove = __devexit_p(ad9850_remove),
};
static __init int ad9850_spi_init(void)
{
return spi_register_driver(&ad9850_driver);
}
module_init(ad9850_spi_init);
static __exit void ad9850_spi_exit(void)
{
spi_unregister_driver(&ad9850_driver);
}
module_exit(ad9850_spi_exit);
MODULE_AUTHOR("Cliff Cai");
MODULE_DESCRIPTION("Analog Devices ad9850 driver");
MODULE_LICENSE("GPL v2");
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