2 * Driver for ADI Direct Digital Synthesis ad9850
4 * Copyright (c) 2010-2010 Analog Devices Inc.
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
11 #include <linux/types.h>
12 #include <linux/mutex.h>
13 #include <linux/device.h>
14 #include <linux/spi/spi.h>
15 #include <linux/slab.h>
16 #include <linux/sysfs.h>
17 #include <linux/module.h>
22 #define DRV_NAME "ad9850"
24 #define value_mask (u16)0xf000
27 /* Register format: 4 bits addr + 12 bits value */
28 struct ad9850_config {
34 struct spi_device *sdev;
37 static ssize_t ad9850_set_parameter(struct device *dev,
38 struct device_attribute *attr,
42 struct spi_message msg;
43 struct spi_transfer xfer;
45 struct ad9850_config *config = (struct ad9850_config *)buf;
46 struct iio_dev *idev = dev_get_drvdata(dev);
47 struct ad9850_state *st = iio_priv(idev);
51 mutex_lock(&st->lock);
53 spi_message_init(&msg);
54 spi_message_add_tail(&xfer, &msg);
55 ret = spi_sync(st->sdev, &msg);
59 mutex_unlock(&st->lock);
61 return ret ? ret : len;
64 static IIO_DEVICE_ATTR(dds, S_IWUSR, NULL, ad9850_set_parameter, 0);
66 static struct attribute *ad9850_attributes[] = {
67 &iio_dev_attr_dds.dev_attr.attr,
71 static const struct attribute_group ad9850_attribute_group = {
72 .attrs = ad9850_attributes,
75 static const struct iio_info ad9850_info = {
76 .attrs = &ad9850_attribute_group,
77 .driver_module = THIS_MODULE,
80 static int __devinit ad9850_probe(struct spi_device *spi)
82 struct ad9850_state *st;
86 idev = iio_allocate_device(sizeof(*st));
91 spi_set_drvdata(spi, idev);
93 mutex_init(&st->lock);
96 idev->dev.parent = &spi->dev;
97 idev->info = &ad9850_info;
98 idev->modes = INDIO_DIRECT_MODE;
100 ret = iio_device_register(idev);
103 spi->max_speed_hz = 2000000;
104 spi->mode = SPI_MODE_3;
105 spi->bits_per_word = 16;
111 iio_free_device(idev);
116 static int __devexit ad9850_remove(struct spi_device *spi)
118 iio_device_unregister(spi_get_drvdata(spi));
119 iio_free_device(spi_get_drvdata(spi));
124 static struct spi_driver ad9850_driver = {
127 .owner = THIS_MODULE,
129 .probe = ad9850_probe,
130 .remove = __devexit_p(ad9850_remove),
133 static __init int ad9850_spi_init(void)
135 return spi_register_driver(&ad9850_driver);
137 module_init(ad9850_spi_init);
139 static __exit void ad9850_spi_exit(void)
141 spi_unregister_driver(&ad9850_driver);
143 module_exit(ad9850_spi_exit);
145 MODULE_AUTHOR("Cliff Cai");
146 MODULE_DESCRIPTION("Analog Devices ad9850 driver");
147 MODULE_LICENSE("GPL v2");
148 MODULE_ALIAS("spi:" DRV_NAME);