/drivers/staging/iio/dds/ad9951.c

  1/*
  2 * Driver for ADI Direct Digital Synthesis ad9951
  3 *
  4 * Copyright (c) 2010 Analog Devices Inc.
  5 *
  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.
  9 *
 10 */
 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
 18#include "../iio.h"
 19#include "../sysfs.h"
 20
 21#define DRV_NAME "ad9951"
 22
 23#define CFR1 0x0
 24#define CFR2 0x1
 25
 26#define AUTO_OSK	(1)
 27#define OSKEN		(1 << 1)
 28#define LOAD_ARR	(1 << 2)
 29
 30#define AUTO_SYNC	(1 << 7)
 31
 32#define LSB_FST		(1)
 33#define SDIO_IPT	(1 << 1)
 34#define CLR_PHA		(1 << 2)
 35#define SINE_OPT	(1 << 4)
 36#define ACLR_PHA	(1 << 5)
 37
 38#define VCO_RANGE	(1 << 2)
 39
 40#define CRS_OPT		(1 << 1)
 41#define HMANU_SYNC	(1 << 2)
 42#define HSPD_SYNC	(1 << 3)
 43
 44/* Register format: 1 byte addr + value */
 45struct ad9951_config {
 46	u8 asf[3];
 47	u8 arr[2];
 48	u8 ftw0[5];
 49	u8 ftw1[3];
 50};
 51
 52struct ad9951_state {
 53	struct mutex lock;
 54	struct spi_device *sdev;
 55};
 56
 57static ssize_t ad9951_set_parameter(struct device *dev,
 58					struct device_attribute *attr,
 59					const char *buf,
 60					size_t len)
 61{
 62	struct spi_message msg;
 63	struct spi_transfer xfer;
 64	int ret;
 65	struct ad9951_config *config = (struct ad9951_config *)buf;
 66	struct iio_dev *idev = dev_get_drvdata(dev);
 67	struct ad9951_state *st = iio_priv(idev);
 68
 69	xfer.len = 3;
 70	xfer.tx_buf = &config->asf[0];
 71	mutex_lock(&st->lock);
 72
 73	spi_message_init(&msg);
 74	spi_message_add_tail(&xfer, &msg);
 75	ret = spi_sync(st->sdev, &msg);
 76	if (ret)
 77		goto error_ret;
 78
 79	xfer.len = 2;
 80	xfer.tx_buf = &config->arr[0];
 81
 82	spi_message_init(&msg);
 83	spi_message_add_tail(&xfer, &msg);
 84	ret = spi_sync(st->sdev, &msg);
 85	if (ret)
 86		goto error_ret;
 87
 88	xfer.len = 5;
 89	xfer.tx_buf = &config->ftw0[0];
 90
 91	spi_message_init(&msg);
 92	spi_message_add_tail(&xfer, &msg);
 93	ret = spi_sync(st->sdev, &msg);
 94	if (ret)
 95		goto error_ret;
 96
 97	xfer.len = 3;
 98	xfer.tx_buf = &config->ftw1[0];
 99
100	spi_message_init(&msg);
101	spi_message_add_tail(&xfer, &msg);
102	ret = spi_sync(st->sdev, &msg);
103	if (ret)
104		goto error_ret;
105error_ret:
106	mutex_unlock(&st->lock);
107
108	return ret ? ret : len;
109}
110
111static IIO_DEVICE_ATTR(dds, S_IWUSR, NULL, ad9951_set_parameter, 0);
112
113static void ad9951_init(struct ad9951_state *st)
114{
115	struct spi_message msg;
116	struct spi_transfer xfer;
117	int ret;
118	u8 cfr[5];
119
120	cfr[0] = CFR1;
121	cfr[1] = 0;
122	cfr[2] = LSB_FST | CLR_PHA | SINE_OPT | ACLR_PHA;
123	cfr[3] = AUTO_OSK | OSKEN | LOAD_ARR;
124	cfr[4] = 0;
125
126	mutex_lock(&st->lock);
127
128	xfer.len = 5;
129	xfer.tx_buf = &cfr;
130
131	spi_message_init(&msg);
132	spi_message_add_tail(&xfer, &msg);
133	ret = spi_sync(st->sdev, &msg);
134	if (ret)
135		goto error_ret;
136
137	cfr[0] = CFR2;
138	cfr[1] = VCO_RANGE;
139	cfr[2] = HSPD_SYNC;
140	cfr[3] = 0;
141
142	xfer.len = 4;
143	xfer.tx_buf = &cfr;
144
145	spi_message_init(&msg);
146	spi_message_add_tail(&xfer, &msg);
147	ret = spi_sync(st->sdev, &msg);
148	if (ret)
149		goto error_ret;
150
151error_ret:
152	mutex_unlock(&st->lock);
153
154
155
156}
157
158static struct attribute *ad9951_attributes[] = {
159	&iio_dev_attr_dds.dev_attr.attr,
160	NULL,
161};
162
163static const struct attribute_group ad9951_attribute_group = {
164	.name = DRV_NAME,
165	.attrs = ad9951_attributes,
166};
167
168static const struct iio_info ad9951_info = {
169	.attrs = &ad9951_attribute_group,
170	.driver_module = THIS_MODULE,
171};
172
173static int __devinit ad9951_probe(struct spi_device *spi)
174{
175	struct ad9951_state *st;
176	struct iio_dev *idev;
177	int ret = 0;
178
179	idev = iio_allocate_device(sizeof(*st));
180	if (idev == NULL) {
181		ret = -ENOMEM;
182		goto error_ret;
183	}
184	spi_set_drvdata(spi, idev);
185	st = iio_priv(idev);
186	mutex_init(&st->lock);
187	st->sdev = spi;
188
189	idev->dev.parent = &spi->dev;
190
191	idev->info = &ad9951_info;
192	idev->modes = INDIO_DIRECT_MODE;
193
194	ret = iio_device_register(idev);
195	if (ret)
196		goto error_free_dev;
197	spi->max_speed_hz = 2000000;
198	spi->mode = SPI_MODE_3;
199	spi->bits_per_word = 8;
200	spi_setup(spi);
201	ad9951_init(st);
202	return 0;
203
204error_free_dev:
205	iio_free_device(idev);
206
207error_ret:
208	return ret;
209}
210
211static int __devexit ad9951_remove(struct spi_device *spi)
212{
213	iio_device_unregister(spi_get_drvdata(spi));
214
215	return 0;
216}
217
218static struct spi_driver ad9951_driver = {
219	.driver = {
220		.name = DRV_NAME,
221		.owner = THIS_MODULE,
222	},
223	.probe = ad9951_probe,
224	.remove = __devexit_p(ad9951_remove),
225};
226
227static __init int ad9951_spi_init(void)
228{
229	return spi_register_driver(&ad9951_driver);
230}
231module_init(ad9951_spi_init);
232
233static __exit void ad9951_spi_exit(void)
234{
235	spi_unregister_driver(&ad9951_driver);
236}
237module_exit(ad9951_spi_exit);
238
239MODULE_AUTHOR("Cliff Cai");
240MODULE_DESCRIPTION("Analog Devices ad9951 driver");
241MODULE_LICENSE("GPL v2");