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/dac081c081.pdf
17 * https://www.ti.com/lit/ds/symlink/dac121c081.pdf
18 */
19
20 #include <linux/iio/iio.h>
21 #include <linux/i2c.h>
22 #include <linux/module.h>
23 #include <linux/mod_devicetable.h>
24 #include <linux/property.h>
25 #include <linux/regulator/consumer.h>
26
27 enum chip_id {
28 single_8bit, single_10bit, single_12bit,
29 quad_8bit, quad_10bit, quad_12bit
30 };
31
32 struct dac5571_spec {
33 u8 num_channels;
34 u8 resolution;
35 };
36
37 static const struct dac5571_spec dac5571_spec[] = {
38 [single_8bit] = {.num_channels = 1, .resolution = 8},
39 [single_10bit] = {.num_channels = 1, .resolution = 10},
40 [single_12bit] = {.num_channels = 1, .resolution = 12},
41 [quad_8bit] = {.num_channels = 4, .resolution = 8},
42 [quad_10bit] = {.num_channels = 4, .resolution = 10},
43 [quad_12bit] = {.num_channels = 4, .resolution = 12},
44 };
45
46 struct dac5571_data {
47 struct i2c_client *client;
48 int id;
49 struct mutex lock;
50 struct regulator *vref;
51 u16 val[4];
52 bool powerdown[4];
53 u8 powerdown_mode[4];
54 struct dac5571_spec const *spec;
55 int (*dac5571_cmd)(struct dac5571_data *data, int channel, u16 val);
56 int (*dac5571_pwrdwn)(struct dac5571_data *data, int channel, u8 pwrdwn);
57 u8 buf[3] __aligned(IIO_DMA_MINALIGN);
58 };
59
60 #define DAC5571_POWERDOWN(mode) ((mode) + 1)
61 #define DAC5571_POWERDOWN_FLAG BIT(0)
62 #define DAC5571_CHANNEL_SELECT 1
63 #define DAC5571_LOADMODE_DIRECT BIT(4)
64 #define DAC5571_SINGLE_PWRDWN_BITS 4
65 #define DAC5571_QUAD_PWRDWN_BITS 6
66
dac5571_cmd_single(struct dac5571_data * data,int channel,u16 val)67 static int dac5571_cmd_single(struct dac5571_data *data, int channel, u16 val)
68 {
69 unsigned int shift;
70
71 shift = 12 - data->spec->resolution;
72 data->buf[1] = val << shift;
73 data->buf[0] = val >> (8 - shift);
74
75 if (i2c_master_send(data->client, data->buf, 2) != 2)
76 return -EIO;
77
78 return 0;
79 }
80
dac5571_cmd_quad(struct dac5571_data * data,int channel,u16 val)81 static int dac5571_cmd_quad(struct dac5571_data *data, int channel, u16 val)
82 {
83 unsigned int shift;
84
85 shift = 16 - data->spec->resolution;
86 data->buf[2] = val << shift;
87 data->buf[1] = (val >> (8 - shift));
88 data->buf[0] = (channel << DAC5571_CHANNEL_SELECT) |
89 DAC5571_LOADMODE_DIRECT;
90
91 if (i2c_master_send(data->client, data->buf, 3) != 3)
92 return -EIO;
93
94 return 0;
95 }
96
dac5571_pwrdwn_single(struct dac5571_data * data,int channel,u8 pwrdwn)97 static int dac5571_pwrdwn_single(struct dac5571_data *data, int channel, u8 pwrdwn)
98 {
99 data->buf[1] = 0;
100 data->buf[0] = pwrdwn << DAC5571_SINGLE_PWRDWN_BITS;
101
102 if (i2c_master_send(data->client, data->buf, 2) != 2)
103 return -EIO;
104
105 return 0;
106 }
107
dac5571_pwrdwn_quad(struct dac5571_data * data,int channel,u8 pwrdwn)108 static int dac5571_pwrdwn_quad(struct dac5571_data *data, int channel, u8 pwrdwn)
109 {
110 data->buf[2] = 0;
111 data->buf[1] = pwrdwn << DAC5571_QUAD_PWRDWN_BITS;
112 data->buf[0] = (channel << DAC5571_CHANNEL_SELECT) |
113 DAC5571_LOADMODE_DIRECT | DAC5571_POWERDOWN_FLAG;
114
115 if (i2c_master_send(data->client, data->buf, 3) != 3)
116 return -EIO;
117
118 return 0;
119 }
120
121 static const char *const dac5571_powerdown_modes[] = {
122 "1kohm_to_gnd", "100kohm_to_gnd", "three_state",
123 };
124
dac5571_get_powerdown_mode(struct iio_dev * indio_dev,const struct iio_chan_spec * chan)125 static int dac5571_get_powerdown_mode(struct iio_dev *indio_dev,
126 const struct iio_chan_spec *chan)
127 {
128 struct dac5571_data *data = iio_priv(indio_dev);
129
130 return data->powerdown_mode[chan->channel];
131 }
132
dac5571_set_powerdown_mode(struct iio_dev * indio_dev,const struct iio_chan_spec * chan,unsigned int mode)133 static int dac5571_set_powerdown_mode(struct iio_dev *indio_dev,
134 const struct iio_chan_spec *chan,
135 unsigned int mode)
136 {
137 struct dac5571_data *data = iio_priv(indio_dev);
138 int ret = 0;
139
140 if (data->powerdown_mode[chan->channel] == mode)
141 return 0;
142
143 mutex_lock(&data->lock);
144 if (data->powerdown[chan->channel]) {
145 ret = data->dac5571_pwrdwn(data, chan->channel,
146 DAC5571_POWERDOWN(mode));
147 if (ret)
148 goto out;
149 }
150 data->powerdown_mode[chan->channel] = mode;
151
152 out:
153 mutex_unlock(&data->lock);
154
155 return ret;
156 }
157
158 static const struct iio_enum dac5571_powerdown_mode = {
159 .items = dac5571_powerdown_modes,
160 .num_items = ARRAY_SIZE(dac5571_powerdown_modes),
161 .get = dac5571_get_powerdown_mode,
162 .set = dac5571_set_powerdown_mode,
163 };
164
dac5571_read_powerdown(struct iio_dev * indio_dev,uintptr_t private,const struct iio_chan_spec * chan,char * buf)165 static ssize_t dac5571_read_powerdown(struct iio_dev *indio_dev,
166 uintptr_t private,
167 const struct iio_chan_spec *chan,
168 char *buf)
169 {
170 struct dac5571_data *data = iio_priv(indio_dev);
171
172 return sysfs_emit(buf, "%d\n", data->powerdown[chan->channel]);
173 }
174
dac5571_write_powerdown(struct iio_dev * indio_dev,uintptr_t private,const struct iio_chan_spec * chan,const char * buf,size_t len)175 static ssize_t dac5571_write_powerdown(struct iio_dev *indio_dev,
176 uintptr_t private,
177 const struct iio_chan_spec *chan,
178 const char *buf, size_t len)
179 {
180 struct dac5571_data *data = iio_priv(indio_dev);
181 bool powerdown;
182 int ret;
183
184 ret = kstrtobool(buf, &powerdown);
185 if (ret)
186 return ret;
187
188 if (data->powerdown[chan->channel] == powerdown)
189 return len;
190
191 mutex_lock(&data->lock);
192 if (powerdown)
193 ret = data->dac5571_pwrdwn(data, chan->channel,
194 DAC5571_POWERDOWN(data->powerdown_mode[chan->channel]));
195 else
196 ret = data->dac5571_cmd(data, chan->channel,
197 data->val[chan->channel]);
198 if (ret)
199 goto out;
200
201 data->powerdown[chan->channel] = powerdown;
202
203 out:
204 mutex_unlock(&data->lock);
205
206 return ret ? ret : len;
207 }
208
209
210 static const struct iio_chan_spec_ext_info dac5571_ext_info[] = {
211 {
212 .name = "powerdown",
213 .read = dac5571_read_powerdown,
214 .write = dac5571_write_powerdown,
215 .shared = IIO_SEPARATE,
216 },
217 IIO_ENUM("powerdown_mode", IIO_SEPARATE, &dac5571_powerdown_mode),
218 IIO_ENUM_AVAILABLE("powerdown_mode", IIO_SHARED_BY_TYPE, &dac5571_powerdown_mode),
219 {},
220 };
221
222 #define dac5571_CHANNEL(chan, name) { \
223 .type = IIO_VOLTAGE, \
224 .channel = (chan), \
225 .address = (chan), \
226 .indexed = true, \
227 .output = true, \
228 .datasheet_name = name, \
229 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
230 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
231 .ext_info = dac5571_ext_info, \
232 }
233
234 static const struct iio_chan_spec dac5571_channels[] = {
235 dac5571_CHANNEL(0, "A"),
236 dac5571_CHANNEL(1, "B"),
237 dac5571_CHANNEL(2, "C"),
238 dac5571_CHANNEL(3, "D"),
239 };
240
dac5571_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)241 static int dac5571_read_raw(struct iio_dev *indio_dev,
242 struct iio_chan_spec const *chan,
243 int *val, int *val2, long mask)
244 {
245 struct dac5571_data *data = iio_priv(indio_dev);
246 int ret;
247
248 switch (mask) {
249 case IIO_CHAN_INFO_RAW:
250 *val = data->val[chan->channel];
251 return IIO_VAL_INT;
252
253 case IIO_CHAN_INFO_SCALE:
254 ret = regulator_get_voltage(data->vref);
255 if (ret < 0)
256 return ret;
257
258 *val = ret / 1000;
259 *val2 = data->spec->resolution;
260 return IIO_VAL_FRACTIONAL_LOG2;
261
262 default:
263 return -EINVAL;
264 }
265 }
266
dac5571_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)267 static int dac5571_write_raw(struct iio_dev *indio_dev,
268 struct iio_chan_spec const *chan,
269 int val, int val2, long mask)
270 {
271 struct dac5571_data *data = iio_priv(indio_dev);
272 int ret;
273
274 switch (mask) {
275 case IIO_CHAN_INFO_RAW:
276 if (data->val[chan->channel] == val)
277 return 0;
278
279 if (val >= (1 << data->spec->resolution) || val < 0)
280 return -EINVAL;
281
282 if (data->powerdown[chan->channel])
283 return -EBUSY;
284
285 mutex_lock(&data->lock);
286 ret = data->dac5571_cmd(data, chan->channel, val);
287 if (ret == 0)
288 data->val[chan->channel] = val;
289 mutex_unlock(&data->lock);
290 return ret;
291
292 default:
293 return -EINVAL;
294 }
295 }
296
dac5571_write_raw_get_fmt(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,long mask)297 static int dac5571_write_raw_get_fmt(struct iio_dev *indio_dev,
298 struct iio_chan_spec const *chan,
299 long mask)
300 {
301 return IIO_VAL_INT;
302 }
303
304 static const struct iio_info dac5571_info = {
305 .read_raw = dac5571_read_raw,
306 .write_raw = dac5571_write_raw,
307 .write_raw_get_fmt = dac5571_write_raw_get_fmt,
308 };
309
dac5571_probe(struct i2c_client * client)310 static int dac5571_probe(struct i2c_client *client)
311 {
312 const struct i2c_device_id *id = i2c_client_get_device_id(client);
313 struct device *dev = &client->dev;
314 const struct dac5571_spec *spec;
315 struct dac5571_data *data;
316 struct iio_dev *indio_dev;
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 spec = i2c_get_match_data(client);
333
334 indio_dev->num_channels = spec->num_channels;
335 data->spec = spec;
336
337 data->vref = devm_regulator_get(dev, "vref");
338 if (IS_ERR(data->vref))
339 return PTR_ERR(data->vref);
340
341 ret = regulator_enable(data->vref);
342 if (ret < 0)
343 return ret;
344
345 mutex_init(&data->lock);
346
347 switch (spec->num_channels) {
348 case 1:
349 data->dac5571_cmd = dac5571_cmd_single;
350 data->dac5571_pwrdwn = dac5571_pwrdwn_single;
351 break;
352 case 4:
353 data->dac5571_cmd = dac5571_cmd_quad;
354 data->dac5571_pwrdwn = dac5571_pwrdwn_quad;
355 break;
356 default:
357 ret = -EINVAL;
358 goto err;
359 }
360
361 for (i = 0; i < spec->num_channels; i++) {
362 ret = data->dac5571_cmd(data, i, 0);
363 if (ret) {
364 dev_err(dev, "failed to initialize channel %d to 0\n", i);
365 goto err;
366 }
367 }
368
369 ret = iio_device_register(indio_dev);
370 if (ret)
371 goto err;
372
373 return 0;
374
375 err:
376 regulator_disable(data->vref);
377 return ret;
378 }
379
dac5571_remove(struct i2c_client * i2c)380 static void dac5571_remove(struct i2c_client *i2c)
381 {
382 struct iio_dev *indio_dev = i2c_get_clientdata(i2c);
383 struct dac5571_data *data = iio_priv(indio_dev);
384
385 iio_device_unregister(indio_dev);
386 regulator_disable(data->vref);
387 }
388
389 static const struct of_device_id dac5571_of_id[] = {
390 {.compatible = "ti,dac081c081", .data = &dac5571_spec[single_8bit] },
391 {.compatible = "ti,dac121c081", .data = &dac5571_spec[single_12bit] },
392 {.compatible = "ti,dac5571", .data = &dac5571_spec[single_8bit] },
393 {.compatible = "ti,dac6571", .data = &dac5571_spec[single_10bit] },
394 {.compatible = "ti,dac7571", .data = &dac5571_spec[single_12bit] },
395 {.compatible = "ti,dac5574", .data = &dac5571_spec[quad_8bit] },
396 {.compatible = "ti,dac6574", .data = &dac5571_spec[quad_10bit] },
397 {.compatible = "ti,dac7574", .data = &dac5571_spec[quad_12bit] },
398 {.compatible = "ti,dac5573", .data = &dac5571_spec[quad_8bit] },
399 {.compatible = "ti,dac6573", .data = &dac5571_spec[quad_10bit] },
400 {.compatible = "ti,dac7573", .data = &dac5571_spec[quad_12bit] },
401 {}
402 };
403 MODULE_DEVICE_TABLE(of, dac5571_of_id);
404
405 static const struct i2c_device_id dac5571_id[] = {
406 {"dac081c081", (kernel_ulong_t)&dac5571_spec[single_8bit] },
407 {"dac121c081", (kernel_ulong_t)&dac5571_spec[single_12bit] },
408 {"dac5571", (kernel_ulong_t)&dac5571_spec[single_8bit] },
409 {"dac6571", (kernel_ulong_t)&dac5571_spec[single_10bit] },
410 {"dac7571", (kernel_ulong_t)&dac5571_spec[single_12bit] },
411 {"dac5574", (kernel_ulong_t)&dac5571_spec[quad_8bit] },
412 {"dac6574", (kernel_ulong_t)&dac5571_spec[quad_10bit] },
413 {"dac7574", (kernel_ulong_t)&dac5571_spec[quad_12bit] },
414 {"dac5573", (kernel_ulong_t)&dac5571_spec[quad_8bit] },
415 {"dac6573", (kernel_ulong_t)&dac5571_spec[quad_10bit] },
416 {"dac7573", (kernel_ulong_t)&dac5571_spec[quad_12bit] },
417 {}
418 };
419 MODULE_DEVICE_TABLE(i2c, dac5571_id);
420
421 static struct i2c_driver dac5571_driver = {
422 .driver = {
423 .name = "ti-dac5571",
424 .of_match_table = dac5571_of_id,
425 },
426 .probe = dac5571_probe,
427 .remove = dac5571_remove,
428 .id_table = dac5571_id,
429 };
430 module_i2c_driver(dac5571_driver);
431
432 MODULE_AUTHOR("Sean Nyekjaer <sean@geanix.dk>");
433 MODULE_DESCRIPTION("Texas Instruments 8/10/12-bit 1/4-channel DAC driver");
434 MODULE_LICENSE("GPL v2");
435