1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * ti-dac5571.c - Texas Instruments 8/10/12-bit 1/4-channel DAC driver
4 *
5 * Copyright (C) 2018 Prevas A/S
6 *
7 * https://www.ti.com/lit/ds/symlink/dac5571.pdf
8 * https://www.ti.com/lit/ds/symlink/dac6571.pdf
9 * https://www.ti.com/lit/ds/symlink/dac7571.pdf
10 * https://www.ti.com/lit/ds/symlink/dac5574.pdf
11 * https://www.ti.com/lit/ds/symlink/dac6574.pdf
12 * https://www.ti.com/lit/ds/symlink/dac7574.pdf
13 * https://www.ti.com/lit/ds/symlink/dac5573.pdf
14 * https://www.ti.com/lit/ds/symlink/dac6573.pdf
15 * https://www.ti.com/lit/ds/symlink/dac7573.pdf
16 * https://www.ti.com/lit/ds/symlink/dac121c081.pdf
17 */
18
19 #include <linux/iio/iio.h>
20 #include <linux/i2c.h>
21 #include <linux/module.h>
22 #include <linux/mod_devicetable.h>
23 #include <linux/property.h>
24 #include <linux/regulator/consumer.h>
25
26 enum chip_id {
27 single_8bit, single_10bit, single_12bit,
28 quad_8bit, quad_10bit, quad_12bit
29 };
30
31 struct dac5571_spec {
32 u8 num_channels;
33 u8 resolution;
34 };
35
36 static const struct dac5571_spec dac5571_spec[] = {
37 [single_8bit] = {.num_channels = 1, .resolution = 8},
38 [single_10bit] = {.num_channels = 1, .resolution = 10},
39 [single_12bit] = {.num_channels = 1, .resolution = 12},
40 [quad_8bit] = {.num_channels = 4, .resolution = 8},
41 [quad_10bit] = {.num_channels = 4, .resolution = 10},
42 [quad_12bit] = {.num_channels = 4, .resolution = 12},
43 };
44
45 struct dac5571_data {
46 struct i2c_client *client;
47 int id;
48 struct mutex lock;
49 struct regulator *vref;
50 u16 val[4];
51 bool powerdown[4];
52 u8 powerdown_mode[4];
53 struct dac5571_spec const *spec;
54 int (*dac5571_cmd)(struct dac5571_data *data, int channel, u16 val);
55 int (*dac5571_pwrdwn)(struct dac5571_data *data, int channel, u8 pwrdwn);
56 u8 buf[3] __aligned(IIO_DMA_MINALIGN);
57 };
58
59 #define DAC5571_POWERDOWN(mode) ((mode) + 1)
60 #define DAC5571_POWERDOWN_FLAG BIT(0)
61 #define DAC5571_CHANNEL_SELECT 1
62 #define DAC5571_LOADMODE_DIRECT BIT(4)
63 #define DAC5571_SINGLE_PWRDWN_BITS 4
64 #define DAC5571_QUAD_PWRDWN_BITS 6
65
dac5571_cmd_single(struct dac5571_data * data,int channel,u16 val)66 static int dac5571_cmd_single(struct dac5571_data *data, int channel, u16 val)
67 {
68 unsigned int shift;
69
70 shift = 12 - data->spec->resolution;
71 data->buf[1] = val << shift;
72 data->buf[0] = val >> (8 - shift);
73
74 if (i2c_master_send(data->client, data->buf, 2) != 2)
75 return -EIO;
76
77 return 0;
78 }
79
dac5571_cmd_quad(struct dac5571_data * data,int channel,u16 val)80 static int dac5571_cmd_quad(struct dac5571_data *data, int channel, u16 val)
81 {
82 unsigned int shift;
83
84 shift = 16 - data->spec->resolution;
85 data->buf[2] = val << shift;
86 data->buf[1] = (val >> (8 - shift));
87 data->buf[0] = (channel << DAC5571_CHANNEL_SELECT) |
88 DAC5571_LOADMODE_DIRECT;
89
90 if (i2c_master_send(data->client, data->buf, 3) != 3)
91 return -EIO;
92
93 return 0;
94 }
95
dac5571_pwrdwn_single(struct dac5571_data * data,int channel,u8 pwrdwn)96 static int dac5571_pwrdwn_single(struct dac5571_data *data, int channel, u8 pwrdwn)
97 {
98 data->buf[1] = 0;
99 data->buf[0] = pwrdwn << DAC5571_SINGLE_PWRDWN_BITS;
100
101 if (i2c_master_send(data->client, data->buf, 2) != 2)
102 return -EIO;
103
104 return 0;
105 }
106
dac5571_pwrdwn_quad(struct dac5571_data * data,int channel,u8 pwrdwn)107 static int dac5571_pwrdwn_quad(struct dac5571_data *data, int channel, u8 pwrdwn)
108 {
109 data->buf[2] = 0;
110 data->buf[1] = pwrdwn << DAC5571_QUAD_PWRDWN_BITS;
111 data->buf[0] = (channel << DAC5571_CHANNEL_SELECT) |
112 DAC5571_LOADMODE_DIRECT | DAC5571_POWERDOWN_FLAG;
113
114 if (i2c_master_send(data->client, data->buf, 3) != 3)
115 return -EIO;
116
117 return 0;
118 }
119
120 static const char *const dac5571_powerdown_modes[] = {
121 "1kohm_to_gnd", "100kohm_to_gnd", "three_state",
122 };
123
dac5571_get_powerdown_mode(struct iio_dev * indio_dev,const struct iio_chan_spec * chan)124 static int dac5571_get_powerdown_mode(struct iio_dev *indio_dev,
125 const struct iio_chan_spec *chan)
126 {
127 struct dac5571_data *data = iio_priv(indio_dev);
128
129 return data->powerdown_mode[chan->channel];
130 }
131
dac5571_set_powerdown_mode(struct iio_dev * indio_dev,const struct iio_chan_spec * chan,unsigned int mode)132 static int dac5571_set_powerdown_mode(struct iio_dev *indio_dev,
133 const struct iio_chan_spec *chan,
134 unsigned int mode)
135 {
136 struct dac5571_data *data = iio_priv(indio_dev);
137 int ret = 0;
138
139 if (data->powerdown_mode[chan->channel] == mode)
140 return 0;
141
142 mutex_lock(&data->lock);
143 if (data->powerdown[chan->channel]) {
144 ret = data->dac5571_pwrdwn(data, chan->channel,
145 DAC5571_POWERDOWN(mode));
146 if (ret)
147 goto out;
148 }
149 data->powerdown_mode[chan->channel] = mode;
150
151 out:
152 mutex_unlock(&data->lock);
153
154 return ret;
155 }
156
157 static const struct iio_enum dac5571_powerdown_mode = {
158 .items = dac5571_powerdown_modes,
159 .num_items = ARRAY_SIZE(dac5571_powerdown_modes),
160 .get = dac5571_get_powerdown_mode,
161 .set = dac5571_set_powerdown_mode,
162 };
163
dac5571_read_powerdown(struct iio_dev * indio_dev,uintptr_t private,const struct iio_chan_spec * chan,char * buf)164 static ssize_t dac5571_read_powerdown(struct iio_dev *indio_dev,
165 uintptr_t private,
166 const struct iio_chan_spec *chan,
167 char *buf)
168 {
169 struct dac5571_data *data = iio_priv(indio_dev);
170
171 return sysfs_emit(buf, "%d\n", data->powerdown[chan->channel]);
172 }
173
dac5571_write_powerdown(struct iio_dev * indio_dev,uintptr_t private,const struct iio_chan_spec * chan,const char * buf,size_t len)174 static ssize_t dac5571_write_powerdown(struct iio_dev *indio_dev,
175 uintptr_t private,
176 const struct iio_chan_spec *chan,
177 const char *buf, size_t len)
178 {
179 struct dac5571_data *data = iio_priv(indio_dev);
180 bool powerdown;
181 int ret;
182
183 ret = kstrtobool(buf, &powerdown);
184 if (ret)
185 return ret;
186
187 if (data->powerdown[chan->channel] == powerdown)
188 return len;
189
190 mutex_lock(&data->lock);
191 if (powerdown)
192 ret = data->dac5571_pwrdwn(data, chan->channel,
193 DAC5571_POWERDOWN(data->powerdown_mode[chan->channel]));
194 else
195 ret = data->dac5571_cmd(data, chan->channel,
196 data->val[chan->channel]);
197 if (ret)
198 goto out;
199
200 data->powerdown[chan->channel] = powerdown;
201
202 out:
203 mutex_unlock(&data->lock);
204
205 return ret ? ret : len;
206 }
207
208
209 static const struct iio_chan_spec_ext_info dac5571_ext_info[] = {
210 {
211 .name = "powerdown",
212 .read = dac5571_read_powerdown,
213 .write = dac5571_write_powerdown,
214 .shared = IIO_SEPARATE,
215 },
216 IIO_ENUM("powerdown_mode", IIO_SEPARATE, &dac5571_powerdown_mode),
217 IIO_ENUM_AVAILABLE("powerdown_mode", IIO_SHARED_BY_TYPE, &dac5571_powerdown_mode),
218 {},
219 };
220
221 #define dac5571_CHANNEL(chan, name) { \
222 .type = IIO_VOLTAGE, \
223 .channel = (chan), \
224 .address = (chan), \
225 .indexed = true, \
226 .output = true, \
227 .datasheet_name = name, \
228 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
229 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
230 .ext_info = dac5571_ext_info, \
231 }
232
233 static const struct iio_chan_spec dac5571_channels[] = {
234 dac5571_CHANNEL(0, "A"),
235 dac5571_CHANNEL(1, "B"),
236 dac5571_CHANNEL(2, "C"),
237 dac5571_CHANNEL(3, "D"),
238 };
239
dac5571_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)240 static int dac5571_read_raw(struct iio_dev *indio_dev,
241 struct iio_chan_spec const *chan,
242 int *val, int *val2, long mask)
243 {
244 struct dac5571_data *data = iio_priv(indio_dev);
245 int ret;
246
247 switch (mask) {
248 case IIO_CHAN_INFO_RAW:
249 *val = data->val[chan->channel];
250 return IIO_VAL_INT;
251
252 case IIO_CHAN_INFO_SCALE:
253 ret = regulator_get_voltage(data->vref);
254 if (ret < 0)
255 return ret;
256
257 *val = ret / 1000;
258 *val2 = data->spec->resolution;
259 return IIO_VAL_FRACTIONAL_LOG2;
260
261 default:
262 return -EINVAL;
263 }
264 }
265
dac5571_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)266 static int dac5571_write_raw(struct iio_dev *indio_dev,
267 struct iio_chan_spec const *chan,
268 int val, int val2, long mask)
269 {
270 struct dac5571_data *data = iio_priv(indio_dev);
271 int ret;
272
273 switch (mask) {
274 case IIO_CHAN_INFO_RAW:
275 if (data->val[chan->channel] == val)
276 return 0;
277
278 if (val >= (1 << data->spec->resolution) || val < 0)
279 return -EINVAL;
280
281 if (data->powerdown[chan->channel])
282 return -EBUSY;
283
284 mutex_lock(&data->lock);
285 ret = data->dac5571_cmd(data, chan->channel, val);
286 if (ret == 0)
287 data->val[chan->channel] = val;
288 mutex_unlock(&data->lock);
289 return ret;
290
291 default:
292 return -EINVAL;
293 }
294 }
295
dac5571_write_raw_get_fmt(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,long mask)296 static int dac5571_write_raw_get_fmt(struct iio_dev *indio_dev,
297 struct iio_chan_spec const *chan,
298 long mask)
299 {
300 return IIO_VAL_INT;
301 }
302
303 static const struct iio_info dac5571_info = {
304 .read_raw = dac5571_read_raw,
305 .write_raw = dac5571_write_raw,
306 .write_raw_get_fmt = dac5571_write_raw_get_fmt,
307 };
308
dac5571_probe(struct i2c_client * client)309 static int dac5571_probe(struct i2c_client *client)
310 {
311 const struct i2c_device_id *id = i2c_client_get_device_id(client);
312 struct device *dev = &client->dev;
313 const struct dac5571_spec *spec;
314 struct dac5571_data *data;
315 struct iio_dev *indio_dev;
316 enum chip_id chip_id;
317 int ret, i;
318
319 indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
320 if (!indio_dev)
321 return -ENOMEM;
322
323 data = iio_priv(indio_dev);
324 i2c_set_clientdata(client, indio_dev);
325 data->client = client;
326
327 indio_dev->info = &dac5571_info;
328 indio_dev->name = id->name;
329 indio_dev->modes = INDIO_DIRECT_MODE;
330 indio_dev->channels = dac5571_channels;
331
332 if (dev_fwnode(dev))
333 chip_id = (uintptr_t)device_get_match_data(dev);
334 else
335 chip_id = id->driver_data;
336
337 spec = &dac5571_spec[chip_id];
338
339 indio_dev->num_channels = spec->num_channels;
340 data->spec = spec;
341
342 data->vref = devm_regulator_get(dev, "vref");
343 if (IS_ERR(data->vref))
344 return PTR_ERR(data->vref);
345
346 ret = regulator_enable(data->vref);
347 if (ret < 0)
348 return ret;
349
350 mutex_init(&data->lock);
351
352 switch (spec->num_channels) {
353 case 1:
354 data->dac5571_cmd = dac5571_cmd_single;
355 data->dac5571_pwrdwn = dac5571_pwrdwn_single;
356 break;
357 case 4:
358 data->dac5571_cmd = dac5571_cmd_quad;
359 data->dac5571_pwrdwn = dac5571_pwrdwn_quad;
360 break;
361 default:
362 ret = -EINVAL;
363 goto err;
364 }
365
366 for (i = 0; i < spec->num_channels; i++) {
367 ret = data->dac5571_cmd(data, i, 0);
368 if (ret) {
369 dev_err(dev, "failed to initialize channel %d to 0\n", i);
370 goto err;
371 }
372 }
373
374 ret = iio_device_register(indio_dev);
375 if (ret)
376 goto err;
377
378 return 0;
379
380 err:
381 regulator_disable(data->vref);
382 return ret;
383 }
384
dac5571_remove(struct i2c_client * i2c)385 static void dac5571_remove(struct i2c_client *i2c)
386 {
387 struct iio_dev *indio_dev = i2c_get_clientdata(i2c);
388 struct dac5571_data *data = iio_priv(indio_dev);
389
390 iio_device_unregister(indio_dev);
391 regulator_disable(data->vref);
392 }
393
394 static const struct of_device_id dac5571_of_id[] = {
395 {.compatible = "ti,dac5571", .data = (void *)single_8bit},
396 {.compatible = "ti,dac6571", .data = (void *)single_10bit},
397 {.compatible = "ti,dac7571", .data = (void *)single_12bit},
398 {.compatible = "ti,dac5574", .data = (void *)quad_8bit},
399 {.compatible = "ti,dac6574", .data = (void *)quad_10bit},
400 {.compatible = "ti,dac7574", .data = (void *)quad_12bit},
401 {.compatible = "ti,dac5573", .data = (void *)quad_8bit},
402 {.compatible = "ti,dac6573", .data = (void *)quad_10bit},
403 {.compatible = "ti,dac7573", .data = (void *)quad_12bit},
404 {.compatible = "ti,dac121c081", .data = (void *)single_12bit},
405 {}
406 };
407 MODULE_DEVICE_TABLE(of, dac5571_of_id);
408
409 static const struct i2c_device_id dac5571_id[] = {
410 {"dac5571", single_8bit},
411 {"dac6571", single_10bit},
412 {"dac7571", single_12bit},
413 {"dac5574", quad_8bit},
414 {"dac6574", quad_10bit},
415 {"dac7574", quad_12bit},
416 {"dac5573", quad_8bit},
417 {"dac6573", quad_10bit},
418 {"dac7573", quad_12bit},
419 {"dac121c081", single_12bit},
420 {}
421 };
422 MODULE_DEVICE_TABLE(i2c, dac5571_id);
423
424 static struct i2c_driver dac5571_driver = {
425 .driver = {
426 .name = "ti-dac5571",
427 .of_match_table = dac5571_of_id,
428 },
429 .probe = dac5571_probe,
430 .remove = dac5571_remove,
431 .id_table = dac5571_id,
432 };
433 module_i2c_driver(dac5571_driver);
434
435 MODULE_AUTHOR("Sean Nyekjaer <sean@geanix.dk>");
436 MODULE_DESCRIPTION("Texas Instruments 8/10/12-bit 1/4-channel DAC driver");
437 MODULE_LICENSE("GPL v2");
438