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