blob: fff7d0762c0cb10fd4afbc40d9ac6799e10dad31 [file] [log] [blame]
Lars-Peter Clausen8341dc02012-10-16 17:29:00 +01001/*
2 * AD5415, AD5426, AD5429, AD5432, AD5439, AD5443, AD5449 Digital to Analog
3 * Converter driver.
4 *
5 * Copyright 2012 Analog Devices Inc.
6 * Author: Lars-Peter Clausen <lars@metafoo.de>
7 *
8 * Licensed under the GPL-2.
9 */
10
11#include <linux/device.h>
12#include <linux/err.h>
13#include <linux/module.h>
14#include <linux/kernel.h>
15#include <linux/spi/spi.h>
16#include <linux/slab.h>
17#include <linux/sysfs.h>
18#include <linux/regulator/consumer.h>
19#include <asm/unaligned.h>
20
21#include <linux/iio/iio.h>
22#include <linux/iio/sysfs.h>
23
24#include <linux/platform_data/ad5449.h>
25
26#define AD5449_MAX_CHANNELS 2
27#define AD5449_MAX_VREFS 2
28
29#define AD5449_CMD_NOOP 0x0
30#define AD5449_CMD_LOAD_AND_UPDATE(x) (0x1 + (x) * 3)
31#define AD5449_CMD_READ(x) (0x2 + (x) * 3)
32#define AD5449_CMD_LOAD(x) (0x3 + (x) * 3)
33#define AD5449_CMD_CTRL 13
34
35#define AD5449_CTRL_SDO_OFFSET 10
36#define AD5449_CTRL_DAISY_CHAIN BIT(9)
37#define AD5449_CTRL_HCLR_TO_MIDSCALE BIT(8)
38#define AD5449_CTRL_SAMPLE_RISING BIT(7)
39
40/**
41 * struct ad5449_chip_info - chip specific information
42 * @channels: Channel specification
43 * @num_channels: Number of channels
44 * @has_ctrl: Chip has a control register
45 */
46struct ad5449_chip_info {
47 const struct iio_chan_spec *channels;
48 unsigned int num_channels;
49 bool has_ctrl;
50};
51
52/**
53 * struct ad5449 - driver instance specific data
54 * @spi: the SPI device for this driver instance
55 * @chip_info: chip model specific constants, available modes etc
56 * @vref_reg: vref supply regulators
57 * @has_sdo: whether the SDO line is connected
58 * @dac_cache: Cache for the DAC values
59 * @data: spi transfer buffers
60 */
61struct ad5449 {
62 struct spi_device *spi;
63 const struct ad5449_chip_info *chip_info;
64 struct regulator_bulk_data vref_reg[AD5449_MAX_VREFS];
65
66 bool has_sdo;
67 uint16_t dac_cache[AD5449_MAX_CHANNELS];
68
69 /*
70 * DMA (thus cache coherency maintenance) requires the
71 * transfer buffers to live in their own cache lines.
72 */
73 __be16 data[2] ____cacheline_aligned;
74};
75
76enum ad5449_type {
77 ID_AD5426,
78 ID_AD5429,
79 ID_AD5432,
80 ID_AD5439,
81 ID_AD5443,
82 ID_AD5449,
83};
84
85static int ad5449_write(struct iio_dev *indio_dev, unsigned int addr,
86 unsigned int val)
87{
88 struct ad5449 *st = iio_priv(indio_dev);
89 int ret;
90
91 mutex_lock(&indio_dev->mlock);
92 st->data[0] = cpu_to_be16((addr << 12) | val);
93 ret = spi_write(st->spi, st->data, 2);
94 mutex_unlock(&indio_dev->mlock);
95
96 return ret;
97}
98
99static int ad5449_read(struct iio_dev *indio_dev, unsigned int addr,
100 unsigned int *val)
101{
102 struct ad5449 *st = iio_priv(indio_dev);
103 int ret;
104 struct spi_message msg;
105 struct spi_transfer t[] = {
106 {
107 .tx_buf = &st->data[0],
108 .len = 2,
109 .cs_change = 1,
110 }, {
111 .tx_buf = &st->data[1],
112 .rx_buf = &st->data[1],
113 .len = 2,
114 },
115 };
116
117 spi_message_init(&msg);
118 spi_message_add_tail(&t[0], &msg);
119 spi_message_add_tail(&t[1], &msg);
120
121 mutex_lock(&indio_dev->mlock);
122 st->data[0] = cpu_to_be16(addr << 12);
123 st->data[1] = cpu_to_be16(AD5449_CMD_NOOP);
124
125 ret = spi_sync(st->spi, &msg);
126 if (ret < 0)
Dan Carpenter0c88d232012-10-24 08:13:00 +0100127 goto out_unlock;
Lars-Peter Clausen8341dc02012-10-16 17:29:00 +0100128
129 *val = be16_to_cpu(st->data[1]);
Lars-Peter Clausen8341dc02012-10-16 17:29:00 +0100130
Dan Carpenter0c88d232012-10-24 08:13:00 +0100131out_unlock:
132 mutex_unlock(&indio_dev->mlock);
133 return ret;
Lars-Peter Clausen8341dc02012-10-16 17:29:00 +0100134}
135
136static int ad5449_read_raw(struct iio_dev *indio_dev,
137 struct iio_chan_spec const *chan, int *val, int *val2, long info)
138{
139 struct ad5449 *st = iio_priv(indio_dev);
140 struct regulator_bulk_data *reg;
141 int scale_uv;
142 int ret;
143
144 switch (info) {
145 case IIO_CHAN_INFO_RAW:
146 if (st->has_sdo) {
147 ret = ad5449_read(indio_dev,
148 AD5449_CMD_READ(chan->address), val);
149 if (ret)
150 return ret;
151 *val &= 0xfff;
152 } else {
153 *val = st->dac_cache[chan->address];
154 }
155
156 return IIO_VAL_INT;
157 case IIO_CHAN_INFO_SCALE:
158 reg = &st->vref_reg[chan->channel];
159 scale_uv = regulator_get_voltage(reg->consumer);
160 if (scale_uv < 0)
161 return scale_uv;
162
163 *val = scale_uv / 1000;
164 *val2 = chan->scan_type.realbits;
165
166 return IIO_VAL_FRACTIONAL_LOG2;
167 default:
168 break;
169 }
170
171 return -EINVAL;
172}
173
174static int ad5449_write_raw(struct iio_dev *indio_dev,
175 struct iio_chan_spec const *chan, int val, int val2, long info)
176{
177 struct ad5449 *st = iio_priv(indio_dev);
178 int ret;
179
180 switch (info) {
181 case IIO_CHAN_INFO_RAW:
182 if (val < 0 || val >= (1 << chan->scan_type.realbits))
183 return -EINVAL;
184
185 ret = ad5449_write(indio_dev,
186 AD5449_CMD_LOAD_AND_UPDATE(chan->address),
187 val << chan->scan_type.shift);
188 if (ret == 0)
189 st->dac_cache[chan->address] = val;
190 break;
191 default:
192 ret = -EINVAL;
193 }
194
195 return ret;
196}
197
198static const struct iio_info ad5449_info = {
199 .read_raw = ad5449_read_raw,
200 .write_raw = ad5449_write_raw,
201 .driver_module = THIS_MODULE,
202};
203
204#define AD5449_CHANNEL(chan, bits) { \
205 .type = IIO_VOLTAGE, \
206 .indexed = 1, \
207 .output = 1, \
208 .channel = (chan), \
Jonathan Cameronf8c62712013-02-27 19:10:50 +0000209 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
210 BIT(IIO_CHAN_INFO_SCALE), \
Lars-Peter Clausen8341dc02012-10-16 17:29:00 +0100211 .address = (chan), \
212 .scan_type = IIO_ST('u', (bits), 16, 12 - (bits)), \
213}
214
215#define DECLARE_AD5449_CHANNELS(name, bits) \
216const struct iio_chan_spec name[] = { \
217 AD5449_CHANNEL(0, bits), \
218 AD5449_CHANNEL(1, bits), \
219}
220
221static DECLARE_AD5449_CHANNELS(ad5429_channels, 8);
222static DECLARE_AD5449_CHANNELS(ad5439_channels, 10);
223static DECLARE_AD5449_CHANNELS(ad5449_channels, 12);
224
225static const struct ad5449_chip_info ad5449_chip_info[] = {
226 [ID_AD5426] = {
227 .channels = ad5429_channels,
228 .num_channels = 1,
229 .has_ctrl = false,
230 },
231 [ID_AD5429] = {
232 .channels = ad5429_channels,
233 .num_channels = 2,
234 .has_ctrl = true,
235 },
236 [ID_AD5432] = {
237 .channels = ad5439_channels,
238 .num_channels = 1,
239 .has_ctrl = false,
240 },
241 [ID_AD5439] = {
242 .channels = ad5439_channels,
243 .num_channels = 2,
244 .has_ctrl = true,
245 },
246 [ID_AD5443] = {
247 .channels = ad5449_channels,
248 .num_channels = 1,
249 .has_ctrl = false,
250 },
251 [ID_AD5449] = {
252 .channels = ad5449_channels,
253 .num_channels = 2,
254 .has_ctrl = true,
255 },
256};
257
258static const char *ad5449_vref_name(struct ad5449 *st, int n)
259{
260 if (st->chip_info->num_channels == 1)
261 return "VREF";
262
263 if (n == 0)
264 return "VREFA";
265 else
266 return "VREFB";
267}
268
Greg Kroah-Hartmanfc526922012-12-21 13:21:43 -0800269static int ad5449_spi_probe(struct spi_device *spi)
Lars-Peter Clausen8341dc02012-10-16 17:29:00 +0100270{
271 struct ad5449_platform_data *pdata = spi->dev.platform_data;
272 const struct spi_device_id *id = spi_get_device_id(spi);
273 struct iio_dev *indio_dev;
274 struct ad5449 *st;
275 unsigned int i;
276 int ret;
277
Sachin Kamatcd5e5782013-08-19 12:38:00 +0100278 indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
Lars-Peter Clausen8341dc02012-10-16 17:29:00 +0100279 if (indio_dev == NULL)
280 return -ENOMEM;
281
282 st = iio_priv(indio_dev);
283 spi_set_drvdata(spi, indio_dev);
284
285 st->chip_info = &ad5449_chip_info[id->driver_data];
286 st->spi = spi;
287
288 for (i = 0; i < st->chip_info->num_channels; ++i)
289 st->vref_reg[i].supply = ad5449_vref_name(st, i);
290
Sachin Kamatcd5e5782013-08-19 12:38:00 +0100291 ret = devm_regulator_bulk_get(&spi->dev, st->chip_info->num_channels,
Lars-Peter Clausen8341dc02012-10-16 17:29:00 +0100292 st->vref_reg);
293 if (ret)
Sachin Kamatcd5e5782013-08-19 12:38:00 +0100294 return ret;
Lars-Peter Clausen8341dc02012-10-16 17:29:00 +0100295
296 ret = regulator_bulk_enable(st->chip_info->num_channels, st->vref_reg);
297 if (ret)
Sachin Kamatcd5e5782013-08-19 12:38:00 +0100298 return ret;
Lars-Peter Clausen8341dc02012-10-16 17:29:00 +0100299
300 indio_dev->dev.parent = &spi->dev;
301 indio_dev->name = id->name;
302 indio_dev->info = &ad5449_info;
303 indio_dev->modes = INDIO_DIRECT_MODE;
304 indio_dev->channels = st->chip_info->channels;
305 indio_dev->num_channels = st->chip_info->num_channels;
306
307 if (st->chip_info->has_ctrl) {
308 unsigned int ctrl = 0x00;
309 if (pdata) {
310 if (pdata->hardware_clear_to_midscale)
311 ctrl |= AD5449_CTRL_HCLR_TO_MIDSCALE;
312 ctrl |= pdata->sdo_mode << AD5449_CTRL_SDO_OFFSET;
313 st->has_sdo = pdata->sdo_mode != AD5449_SDO_DISABLED;
314 } else {
315 st->has_sdo = true;
316 }
317 ad5449_write(indio_dev, AD5449_CMD_CTRL, ctrl);
318 }
319
320 ret = iio_device_register(indio_dev);
321 if (ret)
322 goto error_disable_reg;
323
324 return 0;
325
326error_disable_reg:
327 regulator_bulk_disable(st->chip_info->num_channels, st->vref_reg);
Lars-Peter Clausen8341dc02012-10-16 17:29:00 +0100328
329 return ret;
330}
331
Greg Kroah-Hartmanfc526922012-12-21 13:21:43 -0800332static int ad5449_spi_remove(struct spi_device *spi)
Lars-Peter Clausen8341dc02012-10-16 17:29:00 +0100333{
334 struct iio_dev *indio_dev = spi_get_drvdata(spi);
335 struct ad5449 *st = iio_priv(indio_dev);
336
337 iio_device_unregister(indio_dev);
338
339 regulator_bulk_disable(st->chip_info->num_channels, st->vref_reg);
Lars-Peter Clausen8341dc02012-10-16 17:29:00 +0100340
341 return 0;
342}
343
344static const struct spi_device_id ad5449_spi_ids[] = {
345 { "ad5415", ID_AD5449 },
346 { "ad5426", ID_AD5426 },
347 { "ad5429", ID_AD5429 },
348 { "ad5432", ID_AD5432 },
349 { "ad5439", ID_AD5439 },
350 { "ad5443", ID_AD5443 },
351 { "ad5449", ID_AD5449 },
352 {}
353};
354MODULE_DEVICE_TABLE(spi, ad5449_spi_ids);
355
356static struct spi_driver ad5449_spi_driver = {
357 .driver = {
358 .name = "ad5449",
359 .owner = THIS_MODULE,
360 },
361 .probe = ad5449_spi_probe,
Greg Kroah-Hartmanfc526922012-12-21 13:21:43 -0800362 .remove = ad5449_spi_remove,
Lars-Peter Clausen8341dc02012-10-16 17:29:00 +0100363 .id_table = ad5449_spi_ids,
364};
365module_spi_driver(ad5449_spi_driver);
366
367MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
368MODULE_DESCRIPTION("Analog Devices AD5449 and similar DACs");
369MODULE_LICENSE("GPL v2");