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9#include <linux/interrupt.h>
10#include <linux/fs.h>
11#include <linux/device.h>
12#include <linux/module.h>
13#include <linux/kernel.h>
14#include <linux/spi/spi.h>
15#include <linux/slab.h>
16#include <linux/sysfs.h>
17#include <linux/regulator/consumer.h>
18
19#include <linux/iio/iio.h>
20#include <linux/iio/sysfs.h>
21
22#define AD5686_DAC_CHANNELS 4
23
24#define AD5686_ADDR(x) ((x) << 16)
25#define AD5686_CMD(x) ((x) << 20)
26
27#define AD5686_ADDR_DAC(chan) (0x1 << (chan))
28#define AD5686_ADDR_ALL_DAC 0xF
29
30#define AD5686_CMD_NOOP 0x0
31#define AD5686_CMD_WRITE_INPUT_N 0x1
32#define AD5686_CMD_UPDATE_DAC_N 0x2
33#define AD5686_CMD_WRITE_INPUT_N_UPDATE_N 0x3
34#define AD5686_CMD_POWERDOWN_DAC 0x4
35#define AD5686_CMD_LDAC_MASK 0x5
36#define AD5686_CMD_RESET 0x6
37#define AD5686_CMD_INTERNAL_REFER_SETUP 0x7
38#define AD5686_CMD_DAISY_CHAIN_ENABLE 0x8
39#define AD5686_CMD_READBACK_ENABLE 0x9
40
41#define AD5686_LDAC_PWRDN_NONE 0x0
42#define AD5686_LDAC_PWRDN_1K 0x1
43#define AD5686_LDAC_PWRDN_100K 0x2
44#define AD5686_LDAC_PWRDN_3STATE 0x3
45
46
47
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50
51
52struct ad5686_chip_info {
53 u16 int_vref_mv;
54 struct iio_chan_spec channel[AD5686_DAC_CHANNELS];
55};
56
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66
67
68struct ad5686_state {
69 struct spi_device *spi;
70 const struct ad5686_chip_info *chip_info;
71 struct regulator *reg;
72 unsigned short vref_mv;
73 unsigned pwr_down_mask;
74 unsigned pwr_down_mode;
75
76
77
78
79
80 union {
81 __be32 d32;
82 u8 d8[4];
83 } data[3] ____cacheline_aligned;
84};
85
86
87
88
89
90enum ad5686_supported_device_ids {
91 ID_AD5684,
92 ID_AD5685,
93 ID_AD5686,
94};
95static int ad5686_spi_write(struct ad5686_state *st,
96 u8 cmd, u8 addr, u16 val, u8 shift)
97{
98 val <<= shift;
99
100 st->data[0].d32 = cpu_to_be32(AD5686_CMD(cmd) |
101 AD5686_ADDR(addr) |
102 val);
103
104 return spi_write(st->spi, &st->data[0].d8[1], 3);
105}
106
107static int ad5686_spi_read(struct ad5686_state *st, u8 addr)
108{
109 struct spi_transfer t[] = {
110 {
111 .tx_buf = &st->data[0].d8[1],
112 .len = 3,
113 .cs_change = 1,
114 }, {
115 .tx_buf = &st->data[1].d8[1],
116 .rx_buf = &st->data[2].d8[1],
117 .len = 3,
118 },
119 };
120 int ret;
121
122 st->data[0].d32 = cpu_to_be32(AD5686_CMD(AD5686_CMD_READBACK_ENABLE) |
123 AD5686_ADDR(addr));
124 st->data[1].d32 = cpu_to_be32(AD5686_CMD(AD5686_CMD_NOOP));
125
126 ret = spi_sync_transfer(st->spi, t, ARRAY_SIZE(t));
127 if (ret < 0)
128 return ret;
129
130 return be32_to_cpu(st->data[2].d32);
131}
132
133static const char * const ad5686_powerdown_modes[] = {
134 "1kohm_to_gnd",
135 "100kohm_to_gnd",
136 "three_state"
137};
138
139static int ad5686_get_powerdown_mode(struct iio_dev *indio_dev,
140 const struct iio_chan_spec *chan)
141{
142 struct ad5686_state *st = iio_priv(indio_dev);
143
144 return ((st->pwr_down_mode >> (chan->channel * 2)) & 0x3) - 1;
145}
146
147static int ad5686_set_powerdown_mode(struct iio_dev *indio_dev,
148 const struct iio_chan_spec *chan, unsigned int mode)
149{
150 struct ad5686_state *st = iio_priv(indio_dev);
151
152 st->pwr_down_mode &= ~(0x3 << (chan->channel * 2));
153 st->pwr_down_mode |= ((mode + 1) << (chan->channel * 2));
154
155 return 0;
156}
157
158static const struct iio_enum ad5686_powerdown_mode_enum = {
159 .items = ad5686_powerdown_modes,
160 .num_items = ARRAY_SIZE(ad5686_powerdown_modes),
161 .get = ad5686_get_powerdown_mode,
162 .set = ad5686_set_powerdown_mode,
163};
164
165static ssize_t ad5686_read_dac_powerdown(struct iio_dev *indio_dev,
166 uintptr_t private, const struct iio_chan_spec *chan, char *buf)
167{
168 struct ad5686_state *st = iio_priv(indio_dev);
169
170 return sprintf(buf, "%d\n", !!(st->pwr_down_mask &
171 (0x3 << (chan->channel * 2))));
172}
173
174static ssize_t ad5686_write_dac_powerdown(struct iio_dev *indio_dev,
175 uintptr_t private, const struct iio_chan_spec *chan, const char *buf,
176 size_t len)
177{
178 bool readin;
179 int ret;
180 struct ad5686_state *st = iio_priv(indio_dev);
181
182 ret = strtobool(buf, &readin);
183 if (ret)
184 return ret;
185
186 if (readin)
187 st->pwr_down_mask |= (0x3 << (chan->channel * 2));
188 else
189 st->pwr_down_mask &= ~(0x3 << (chan->channel * 2));
190
191 ret = ad5686_spi_write(st, AD5686_CMD_POWERDOWN_DAC, 0,
192 st->pwr_down_mask & st->pwr_down_mode, 0);
193
194 return ret ? ret : len;
195}
196
197static int ad5686_read_raw(struct iio_dev *indio_dev,
198 struct iio_chan_spec const *chan,
199 int *val,
200 int *val2,
201 long m)
202{
203 struct ad5686_state *st = iio_priv(indio_dev);
204 int ret;
205
206 switch (m) {
207 case IIO_CHAN_INFO_RAW:
208 mutex_lock(&indio_dev->mlock);
209 ret = ad5686_spi_read(st, chan->address);
210 mutex_unlock(&indio_dev->mlock);
211 if (ret < 0)
212 return ret;
213 *val = ret;
214 return IIO_VAL_INT;
215 case IIO_CHAN_INFO_SCALE:
216 *val = st->vref_mv;
217 *val2 = chan->scan_type.realbits;
218 return IIO_VAL_FRACTIONAL_LOG2;
219 }
220 return -EINVAL;
221}
222
223static int ad5686_write_raw(struct iio_dev *indio_dev,
224 struct iio_chan_spec const *chan,
225 int val,
226 int val2,
227 long mask)
228{
229 struct ad5686_state *st = iio_priv(indio_dev);
230 int ret;
231
232 switch (mask) {
233 case IIO_CHAN_INFO_RAW:
234 if (val > (1 << chan->scan_type.realbits) || val < 0)
235 return -EINVAL;
236
237 mutex_lock(&indio_dev->mlock);
238 ret = ad5686_spi_write(st,
239 AD5686_CMD_WRITE_INPUT_N_UPDATE_N,
240 chan->address,
241 val,
242 chan->scan_type.shift);
243 mutex_unlock(&indio_dev->mlock);
244 break;
245 default:
246 ret = -EINVAL;
247 }
248
249 return ret;
250}
251
252static const struct iio_info ad5686_info = {
253 .read_raw = ad5686_read_raw,
254 .write_raw = ad5686_write_raw,
255 .driver_module = THIS_MODULE,
256};
257
258static const struct iio_chan_spec_ext_info ad5686_ext_info[] = {
259 {
260 .name = "powerdown",
261 .read = ad5686_read_dac_powerdown,
262 .write = ad5686_write_dac_powerdown,
263 .shared = IIO_SEPARATE,
264 },
265 IIO_ENUM("powerdown_mode", IIO_SEPARATE, &ad5686_powerdown_mode_enum),
266 IIO_ENUM_AVAILABLE("powerdown_mode", &ad5686_powerdown_mode_enum),
267 { },
268};
269
270#define AD5868_CHANNEL(chan, bits, _shift) { \
271 .type = IIO_VOLTAGE, \
272 .indexed = 1, \
273 .output = 1, \
274 .channel = chan, \
275 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
276 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),\
277 .address = AD5686_ADDR_DAC(chan), \
278 .scan_type = { \
279 .sign = 'u', \
280 .realbits = (bits), \
281 .storagebits = 16, \
282 .shift = (_shift), \
283 }, \
284 .ext_info = ad5686_ext_info, \
285}
286
287static const struct ad5686_chip_info ad5686_chip_info_tbl[] = {
288 [ID_AD5684] = {
289 .channel[0] = AD5868_CHANNEL(0, 12, 4),
290 .channel[1] = AD5868_CHANNEL(1, 12, 4),
291 .channel[2] = AD5868_CHANNEL(2, 12, 4),
292 .channel[3] = AD5868_CHANNEL(3, 12, 4),
293 .int_vref_mv = 2500,
294 },
295 [ID_AD5685] = {
296 .channel[0] = AD5868_CHANNEL(0, 14, 2),
297 .channel[1] = AD5868_CHANNEL(1, 14, 2),
298 .channel[2] = AD5868_CHANNEL(2, 14, 2),
299 .channel[3] = AD5868_CHANNEL(3, 14, 2),
300 .int_vref_mv = 2500,
301 },
302 [ID_AD5686] = {
303 .channel[0] = AD5868_CHANNEL(0, 16, 0),
304 .channel[1] = AD5868_CHANNEL(1, 16, 0),
305 .channel[2] = AD5868_CHANNEL(2, 16, 0),
306 .channel[3] = AD5868_CHANNEL(3, 16, 0),
307 .int_vref_mv = 2500,
308 },
309};
310
311
312static int ad5686_probe(struct spi_device *spi)
313{
314 struct ad5686_state *st;
315 struct iio_dev *indio_dev;
316 int ret, voltage_uv = 0;
317
318 indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
319 if (indio_dev == NULL)
320 return -ENOMEM;
321
322 st = iio_priv(indio_dev);
323 spi_set_drvdata(spi, indio_dev);
324
325 st->reg = devm_regulator_get_optional(&spi->dev, "vcc");
326 if (!IS_ERR(st->reg)) {
327 ret = regulator_enable(st->reg);
328 if (ret)
329 return ret;
330
331 ret = regulator_get_voltage(st->reg);
332 if (ret < 0)
333 goto error_disable_reg;
334
335 voltage_uv = ret;
336 }
337
338 st->chip_info =
339 &ad5686_chip_info_tbl[spi_get_device_id(spi)->driver_data];
340
341 if (voltage_uv)
342 st->vref_mv = voltage_uv / 1000;
343 else
344 st->vref_mv = st->chip_info->int_vref_mv;
345
346 st->spi = spi;
347
348
349 st->pwr_down_mode = 0x55;
350
351 indio_dev->dev.parent = &spi->dev;
352 indio_dev->name = spi_get_device_id(spi)->name;
353 indio_dev->info = &ad5686_info;
354 indio_dev->modes = INDIO_DIRECT_MODE;
355 indio_dev->channels = st->chip_info->channel;
356 indio_dev->num_channels = AD5686_DAC_CHANNELS;
357
358 ret = ad5686_spi_write(st, AD5686_CMD_INTERNAL_REFER_SETUP, 0,
359 !!voltage_uv, 0);
360 if (ret)
361 goto error_disable_reg;
362
363 ret = iio_device_register(indio_dev);
364 if (ret)
365 goto error_disable_reg;
366
367 return 0;
368
369error_disable_reg:
370 if (!IS_ERR(st->reg))
371 regulator_disable(st->reg);
372 return ret;
373}
374
375static int ad5686_remove(struct spi_device *spi)
376{
377 struct iio_dev *indio_dev = spi_get_drvdata(spi);
378 struct ad5686_state *st = iio_priv(indio_dev);
379
380 iio_device_unregister(indio_dev);
381 if (!IS_ERR(st->reg))
382 regulator_disable(st->reg);
383
384 return 0;
385}
386
387static const struct spi_device_id ad5686_id[] = {
388 {"ad5684", ID_AD5684},
389 {"ad5685", ID_AD5685},
390 {"ad5686", ID_AD5686},
391 {}
392};
393MODULE_DEVICE_TABLE(spi, ad5686_id);
394
395static struct spi_driver ad5686_driver = {
396 .driver = {
397 .name = "ad5686",
398 },
399 .probe = ad5686_probe,
400 .remove = ad5686_remove,
401 .id_table = ad5686_id,
402};
403module_spi_driver(ad5686_driver);
404
405MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
406MODULE_DESCRIPTION("Analog Devices AD5686/85/84 DAC");
407MODULE_LICENSE("GPL v2");
408
