102 lines
		
	
	
	
		
			2.5 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			102 lines
		
	
	
	
		
			2.5 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
|   | /*
 | ||
|  |  *  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/init.h>
 | ||
|  | #include <linux/spi/spi.h>
 | ||
|  | 
 | ||
|  | #define DAC7512_DRV_NAME	"dac7512"
 | ||
|  | #define DRIVER_VERSION		"1.0"
 | ||
|  | 
 | ||
|  | 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; | ||
|  | 
 | ||
|  | 	if (strict_strtoul(buf, 10, &val) < 0) | ||
|  | 		return -EINVAL; | ||
|  | 
 | ||
|  | 	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 __devinit 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 __devexit dac7512_remove(struct spi_device *spi) | ||
|  | { | ||
|  | 	sysfs_remove_group(&spi->dev.kobj, &dac7512_attr_group); | ||
|  | 	return 0; | ||
|  | } | ||
|  | 
 | ||
|  | static struct spi_driver dac7512_driver = { | ||
|  | 	.driver = { | ||
|  | 		.name	= DAC7512_DRV_NAME, | ||
|  | 		.owner	= THIS_MODULE, | ||
|  | 	}, | ||
|  | 	.probe	= dac7512_probe, | ||
|  | 	.remove	= __devexit_p(dac7512_remove), | ||
|  | }; | ||
|  | 
 | ||
|  | static int __init dac7512_init(void) | ||
|  | { | ||
|  | 	return spi_register_driver(&dac7512_driver); | ||
|  | } | ||
|  | 
 | ||
|  | static void __exit dac7512_exit(void) | ||
|  | { | ||
|  | 	spi_unregister_driver(&dac7512_driver); | ||
|  | } | ||
|  | 
 | ||
|  | MODULE_AUTHOR("Daniel Mack <daniel@caiaq.de>"); | ||
|  | MODULE_DESCRIPTION("DAC7512 16-bit DAC"); | ||
|  | MODULE_LICENSE("GPL v2"); | ||
|  | MODULE_VERSION(DRIVER_VERSION); | ||
|  | 
 | ||
|  | module_init(dac7512_init); | ||
|  | module_exit(dac7512_exit); |