ti_dac7512.c
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/*
* dac7512.c - Linux kernel module for
* Texas Instruments DAC7512
*
* Copyright (c) 2009 Daniel Mack <daniel@caiaq.de>
*
* 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., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/module.h>
#include <linux/spi/spi.h>
#include <linux/of.h>
static ssize_t dac7512_store_val(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct spi_device *spi = to_spi_device(dev);
unsigned char tmp[2];
unsigned long val;
int ret;
ret = kstrtoul(buf, 10, &val);
if (ret)
return ret;
tmp[0] = val >> 8;
tmp[1] = val & 0xff;
spi_write(spi, tmp, sizeof(tmp));
return count;
}
static DEVICE_ATTR(value, S_IWUSR, NULL, dac7512_store_val);
static struct attribute *dac7512_attributes[] = {
&dev_attr_value.attr,
NULL
};
static const struct attribute_group dac7512_attr_group = {
.attrs = dac7512_attributes,
};
static int dac7512_probe(struct spi_device *spi)
{
int ret;
spi->bits_per_word = 8;
spi->mode = SPI_MODE_0;
ret = spi_setup(spi);
if (ret < 0)
return ret;
return sysfs_create_group(&spi->dev.kobj, &dac7512_attr_group);
}
static int dac7512_remove(struct spi_device *spi)
{
sysfs_remove_group(&spi->dev.kobj, &dac7512_attr_group);
return 0;
}
static const struct spi_device_id dac7512_id_table[] = {
{ "dac7512", 0 },
{ }
};
MODULE_DEVICE_TABLE(spi, dac7512_id_table);
#ifdef CONFIG_OF
static const struct of_device_id dac7512_of_match[] = {
{ .compatible = "ti,dac7512", },
{ }
};
MODULE_DEVICE_TABLE(of, dac7512_of_match);
#endif
static struct spi_driver dac7512_driver = {
.driver = {
.name = "dac7512",
.of_match_table = of_match_ptr(dac7512_of_match),
},
.probe = dac7512_probe,
.remove = dac7512_remove,
.id_table = dac7512_id_table,
};
module_spi_driver(dac7512_driver);
MODULE_AUTHOR("Daniel Mack <daniel@caiaq.de>");
MODULE_DESCRIPTION("DAC7512 16-bit DAC");
MODULE_LICENSE("GPL v2");