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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
42
43
44
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
54
55
56
57
58
59
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
71
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_transfer t[] = {
105 {
106 .tx_buf = &st->data[0],
107 .len = 2,
108 .cs_change = 1,
109 }, {
110 .tx_buf = &st->data[1],
111 .rx_buf = &st->data[1],
112 .len = 2,
113 },
114 };
115
116 mutex_lock(&indio_dev->mlock);
117 st->data[0] = cpu_to_be16(addr << 12);
118 st->data[1] = cpu_to_be16(AD5449_CMD_NOOP);
119
120 ret = spi_sync_transfer(st->spi, t, ARRAY_SIZE(t));
121 if (ret < 0)
122 goto out_unlock;
123
124 *val = be16_to_cpu(st->data[1]);
125
126out_unlock:
127 mutex_unlock(&indio_dev->mlock);
128 return ret;
129}
130
131static int ad5449_read_raw(struct iio_dev *indio_dev,
132 struct iio_chan_spec const *chan, int *val, int *val2, long info)
133{
134 struct ad5449 *st = iio_priv(indio_dev);
135 struct regulator_bulk_data *reg;
136 int scale_uv;
137 int ret;
138
139 switch (info) {
140 case IIO_CHAN_INFO_RAW:
141 if (st->has_sdo) {
142 ret = ad5449_read(indio_dev,
143 AD5449_CMD_READ(chan->address), val);
144 if (ret)
145 return ret;
146 *val &= 0xfff;
147 } else {
148 *val = st->dac_cache[chan->address];
149 }
150
151 return IIO_VAL_INT;
152 case IIO_CHAN_INFO_SCALE:
153 reg = &st->vref_reg[chan->channel];
154 scale_uv = regulator_get_voltage(reg->consumer);
155 if (scale_uv < 0)
156 return scale_uv;
157
158 *val = scale_uv / 1000;
159 *val2 = chan->scan_type.realbits;
160
161 return IIO_VAL_FRACTIONAL_LOG2;
162 default:
163 break;
164 }
165
166 return -EINVAL;
167}
168
169static int ad5449_write_raw(struct iio_dev *indio_dev,
170 struct iio_chan_spec const *chan, int val, int val2, long info)
171{
172 struct ad5449 *st = iio_priv(indio_dev);
173 int ret;
174
175 switch (info) {
176 case IIO_CHAN_INFO_RAW:
177 if (val < 0 || val >= (1 << chan->scan_type.realbits))
178 return -EINVAL;
179
180 ret = ad5449_write(indio_dev,
181 AD5449_CMD_LOAD_AND_UPDATE(chan->address),
182 val << chan->scan_type.shift);
183 if (ret == 0)
184 st->dac_cache[chan->address] = val;
185 break;
186 default:
187 ret = -EINVAL;
188 }
189
190 return ret;
191}
192
193static const struct iio_info ad5449_info = {
194 .read_raw = ad5449_read_raw,
195 .write_raw = ad5449_write_raw,
196 .driver_module = THIS_MODULE,
197};
198
199#define AD5449_CHANNEL(chan, bits) { \
200 .type = IIO_VOLTAGE, \
201 .indexed = 1, \
202 .output = 1, \
203 .channel = (chan), \
204 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
205 BIT(IIO_CHAN_INFO_SCALE), \
206 .address = (chan), \
207 .scan_type = { \
208 .sign = 'u', \
209 .realbits = (bits), \
210 .storagebits = 16, \
211 .shift = 12 - (bits), \
212 }, \
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
269static int ad5449_spi_probe(struct spi_device *spi)
270{
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
278 indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
279 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
291 ret = devm_regulator_bulk_get(&spi->dev, st->chip_info->num_channels,
292 st->vref_reg);
293 if (ret)
294 return ret;
295
296 ret = regulator_bulk_enable(st->chip_info->num_channels, st->vref_reg);
297 if (ret)
298 return ret;
299
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);
328
329 return ret;
330}
331
332static int ad5449_spi_remove(struct spi_device *spi)
333{
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);
340
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,
362 .remove = ad5449_spi_remove,
363 .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");
370
