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/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 struct mutex lock;
48 struct regulator *vref;
49 u16 val[4];
50 bool powerdown[4];
51 u8 powerdown_mode[4];
52 struct dac5571_spec const *spec;
53 int (*dac5571_cmd)(struct dac5571_data *data, int channel, u16 val);
54 int (*dac5571_pwrdwn)(struct dac5571_data *data, int channel, u8 pwrdwn);
55 u8 buf[3] __aligned(IIO_DMA_MINALIGN);
56 };
57
58 #define DAC5571_POWERDOWN(mode) ((mode) + 1)
59 #define DAC5571_POWERDOWN_FLAG BIT(0)
60 #define DAC5571_CHANNEL_SELECT 1
61 #define DAC5571_LOADMODE_DIRECT BIT(4)
62 #define DAC5571_SINGLE_PWRDWN_BITS 4
63 #define DAC5571_QUAD_PWRDWN_BITS 6
64
dac5571_cmd_single(struct dac5571_data * data,int channel,u16 val)65 static int dac5571_cmd_single(struct dac5571_data *data, int channel, u16 val)
66 {
67 unsigned int shift;
68
69 shift = 12 - data->spec->resolution;
70 data->buf[1] = val << shift;
71 data->buf[0] = val >> (8 - shift);
72
73 if (i2c_master_send(data->client, data->buf, 2) != 2)
74 return -EIO;
75
76 return 0;
77 }
78
dac5571_cmd_quad(struct dac5571_data * data,int channel,u16 val)79 static int dac5571_cmd_quad(struct dac5571_data *data, int channel, u16 val)
80 {
81 unsigned int shift;
82
83 shift = 16 - data->spec->resolution;
84 data->buf[2] = val << shift;
85 data->buf[1] = (val >> (8 - shift));
86 data->buf[0] = (channel << DAC5571_CHANNEL_SELECT) |
87 DAC5571_LOADMODE_DIRECT;
88
89 if (i2c_master_send(data->client, data->buf, 3) != 3)
90 return -EIO;
91
92 return 0;
93 }
94
dac5571_pwrdwn_single(struct dac5571_data * data,int channel,u8 pwrdwn)95 static int dac5571_pwrdwn_single(struct dac5571_data *data, int channel, u8 pwrdwn)
96 {
97 data->buf[1] = 0;
98 data->buf[0] = pwrdwn << DAC5571_SINGLE_PWRDWN_BITS;
99
100 if (i2c_master_send(data->client, data->buf, 2) != 2)
101 return -EIO;
102
103 return 0;
104 }
105
dac5571_pwrdwn_quad(struct dac5571_data * data,int channel,u8 pwrdwn)106 static int dac5571_pwrdwn_quad(struct dac5571_data *data, int channel, u8 pwrdwn)
107 {
108 data->buf[2] = 0;
109 data->buf[1] = pwrdwn << DAC5571_QUAD_PWRDWN_BITS;
110 data->buf[0] = (channel << DAC5571_CHANNEL_SELECT) |
111 DAC5571_LOADMODE_DIRECT | DAC5571_POWERDOWN_FLAG;
112
113 if (i2c_master_send(data->client, data->buf, 3) != 3)
114 return -EIO;
115
116 return 0;
117 }
118
119 static const char *const dac5571_powerdown_modes[] = {
120 "1kohm_to_gnd", "100kohm_to_gnd", "three_state",
121 };
122
dac5571_get_powerdown_mode(struct iio_dev * indio_dev,const struct iio_chan_spec * chan)123 static int dac5571_get_powerdown_mode(struct iio_dev *indio_dev,
124 const struct iio_chan_spec *chan)
125 {
126 struct dac5571_data *data = iio_priv(indio_dev);
127
128 return data->powerdown_mode[chan->channel];
129 }
130
dac5571_set_powerdown_mode(struct iio_dev * indio_dev,const struct iio_chan_spec * chan,unsigned int mode)131 static int dac5571_set_powerdown_mode(struct iio_dev *indio_dev,
132 const struct iio_chan_spec *chan,
133 unsigned int mode)
134 {
135 struct dac5571_data *data = iio_priv(indio_dev);
136 int ret = 0;
137
138 if (data->powerdown_mode[chan->channel] == mode)
139 return 0;
140
141 mutex_lock(&data->lock);
142 if (data->powerdown[chan->channel]) {
143 ret = data->dac5571_pwrdwn(data, chan->channel,
144 DAC5571_POWERDOWN(mode));
145 if (ret)
146 goto out;
147 }
148 data->powerdown_mode[chan->channel] = mode;
149
150 out:
151 mutex_unlock(&data->lock);
152
153 return ret;
154 }
155
156 static const struct iio_enum dac5571_powerdown_mode = {
157 .items = dac5571_powerdown_modes,
158 .num_items = ARRAY_SIZE(dac5571_powerdown_modes),
159 .get = dac5571_get_powerdown_mode,
160 .set = dac5571_set_powerdown_mode,
161 };
162
dac5571_read_powerdown(struct iio_dev * indio_dev,uintptr_t private,const struct iio_chan_spec * chan,char * buf)163 static ssize_t dac5571_read_powerdown(struct iio_dev *indio_dev,
164 uintptr_t private,
165 const struct iio_chan_spec *chan,
166 char *buf)
167 {
168 struct dac5571_data *data = iio_priv(indio_dev);
169
170 return sysfs_emit(buf, "%d\n", data->powerdown[chan->channel]);
171 }
172
dac5571_write_powerdown(struct iio_dev * indio_dev,uintptr_t private,const struct iio_chan_spec * chan,const char * buf,size_t len)173 static ssize_t dac5571_write_powerdown(struct iio_dev *indio_dev,
174 uintptr_t private,
175 const struct iio_chan_spec *chan,
176 const char *buf, size_t len)
177 {
178 struct dac5571_data *data = iio_priv(indio_dev);
179 bool powerdown;
180 int ret;
181
182 ret = kstrtobool(buf, &powerdown);
183 if (ret)
184 return ret;
185
186 if (data->powerdown[chan->channel] == powerdown)
187 return len;
188
189 mutex_lock(&data->lock);
190 if (powerdown)
191 ret = data->dac5571_pwrdwn(data, chan->channel,
192 DAC5571_POWERDOWN(data->powerdown_mode[chan->channel]));
193 else
194 ret = data->dac5571_cmd(data, chan->channel,
195 data->val[chan->channel]);
196 if (ret)
197 goto out;
198
199 data->powerdown[chan->channel] = powerdown;
200
201 out:
202 mutex_unlock(&data->lock);
203
204 return ret ? ret : len;
205 }
206
207
208 static const struct iio_chan_spec_ext_info dac5571_ext_info[] = {
209 {
210 .name = "powerdown",
211 .read = dac5571_read_powerdown,
212 .write = dac5571_write_powerdown,
213 .shared = IIO_SEPARATE,
214 },
215 IIO_ENUM("powerdown_mode", IIO_SEPARATE, &dac5571_powerdown_mode),
216 IIO_ENUM_AVAILABLE("powerdown_mode", IIO_SHARED_BY_TYPE, &dac5571_powerdown_mode),
217 { }
218 };
219
220 #define dac5571_CHANNEL(chan, name) { \
221 .type = IIO_VOLTAGE, \
222 .channel = (chan), \
223 .address = (chan), \
224 .indexed = true, \
225 .output = true, \
226 .datasheet_name = name, \
227 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
228 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
229 .ext_info = dac5571_ext_info, \
230 }
231
232 static const struct iio_chan_spec dac5571_channels[] = {
233 dac5571_CHANNEL(0, "A"),
234 dac5571_CHANNEL(1, "B"),
235 dac5571_CHANNEL(2, "C"),
236 dac5571_CHANNEL(3, "D"),
237 };
238
dac5571_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)239 static int dac5571_read_raw(struct iio_dev *indio_dev,
240 struct iio_chan_spec const *chan,
241 int *val, int *val2, long mask)
242 {
243 struct dac5571_data *data = iio_priv(indio_dev);
244 int ret;
245
246 switch (mask) {
247 case IIO_CHAN_INFO_RAW:
248 *val = data->val[chan->channel];
249 return IIO_VAL_INT;
250
251 case IIO_CHAN_INFO_SCALE:
252 ret = regulator_get_voltage(data->vref);
253 if (ret < 0)
254 return ret;
255
256 *val = ret / 1000;
257 *val2 = data->spec->resolution;
258 return IIO_VAL_FRACTIONAL_LOG2;
259
260 default:
261 return -EINVAL;
262 }
263 }
264
dac5571_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)265 static int dac5571_write_raw(struct iio_dev *indio_dev,
266 struct iio_chan_spec const *chan,
267 int val, int val2, long mask)
268 {
269 struct dac5571_data *data = iio_priv(indio_dev);
270 int ret;
271
272 switch (mask) {
273 case IIO_CHAN_INFO_RAW:
274 if (data->val[chan->channel] == val)
275 return 0;
276
277 if (val >= (1 << data->spec->resolution) || val < 0)
278 return -EINVAL;
279
280 if (data->powerdown[chan->channel])
281 return -EBUSY;
282
283 mutex_lock(&data->lock);
284 ret = data->dac5571_cmd(data, chan->channel, val);
285 if (ret == 0)
286 data->val[chan->channel] = val;
287 mutex_unlock(&data->lock);
288 return ret;
289
290 default:
291 return -EINVAL;
292 }
293 }
294
dac5571_write_raw_get_fmt(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,long mask)295 static int dac5571_write_raw_get_fmt(struct iio_dev *indio_dev,
296 struct iio_chan_spec const *chan,
297 long mask)
298 {
299 return IIO_VAL_INT;
300 }
301
302 static const struct iio_info dac5571_info = {
303 .read_raw = dac5571_read_raw,
304 .write_raw = dac5571_write_raw,
305 .write_raw_get_fmt = dac5571_write_raw_get_fmt,
306 };
307
dac5571_probe(struct i2c_client * client)308 static int dac5571_probe(struct i2c_client *client)
309 {
310 const struct i2c_device_id *id = i2c_client_get_device_id(client);
311 struct device *dev = &client->dev;
312 const struct dac5571_spec *spec;
313 struct dac5571_data *data;
314 struct iio_dev *indio_dev;
315 int ret, i;
316
317 indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
318 if (!indio_dev)
319 return -ENOMEM;
320
321 data = iio_priv(indio_dev);
322 i2c_set_clientdata(client, indio_dev);
323 data->client = client;
324
325 indio_dev->info = &dac5571_info;
326 indio_dev->name = id->name;
327 indio_dev->modes = INDIO_DIRECT_MODE;
328 indio_dev->channels = dac5571_channels;
329
330 spec = i2c_get_match_data(client);
331
332 indio_dev->num_channels = spec->num_channels;
333 data->spec = spec;
334
335 data->vref = devm_regulator_get(dev, "vref");
336 if (IS_ERR(data->vref))
337 return PTR_ERR(data->vref);
338
339 ret = regulator_enable(data->vref);
340 if (ret < 0)
341 return ret;
342
343 mutex_init(&data->lock);
344
345 switch (spec->num_channels) {
346 case 1:
347 data->dac5571_cmd = dac5571_cmd_single;
348 data->dac5571_pwrdwn = dac5571_pwrdwn_single;
349 break;
350 case 4:
351 data->dac5571_cmd = dac5571_cmd_quad;
352 data->dac5571_pwrdwn = dac5571_pwrdwn_quad;
353 break;
354 default:
355 ret = -EINVAL;
356 goto err;
357 }
358
359 for (i = 0; i < spec->num_channels; i++) {
360 ret = data->dac5571_cmd(data, i, 0);
361 if (ret) {
362 dev_err(dev, "failed to initialize channel %d to 0\n", i);
363 goto err;
364 }
365 }
366
367 ret = iio_device_register(indio_dev);
368 if (ret)
369 goto err;
370
371 return 0;
372
373 err:
374 regulator_disable(data->vref);
375 return ret;
376 }
377
dac5571_remove(struct i2c_client * i2c)378 static void dac5571_remove(struct i2c_client *i2c)
379 {
380 struct iio_dev *indio_dev = i2c_get_clientdata(i2c);
381 struct dac5571_data *data = iio_priv(indio_dev);
382
383 iio_device_unregister(indio_dev);
384 regulator_disable(data->vref);
385 }
386
387 static const struct of_device_id dac5571_of_id[] = {
388 {.compatible = "ti,dac081c081", .data = &dac5571_spec[single_8bit] },
389 {.compatible = "ti,dac121c081", .data = &dac5571_spec[single_12bit] },
390 {.compatible = "ti,dac5571", .data = &dac5571_spec[single_8bit] },
391 {.compatible = "ti,dac6571", .data = &dac5571_spec[single_10bit] },
392 {.compatible = "ti,dac7571", .data = &dac5571_spec[single_12bit] },
393 {.compatible = "ti,dac5574", .data = &dac5571_spec[quad_8bit] },
394 {.compatible = "ti,dac6574", .data = &dac5571_spec[quad_10bit] },
395 {.compatible = "ti,dac7574", .data = &dac5571_spec[quad_12bit] },
396 {.compatible = "ti,dac5573", .data = &dac5571_spec[quad_8bit] },
397 {.compatible = "ti,dac6573", .data = &dac5571_spec[quad_10bit] },
398 {.compatible = "ti,dac7573", .data = &dac5571_spec[quad_12bit] },
399 { }
400 };
401 MODULE_DEVICE_TABLE(of, dac5571_of_id);
402
403 static const struct i2c_device_id dac5571_id[] = {
404 { .name = "dac081c081", .driver_data = (kernel_ulong_t)&dac5571_spec[single_8bit] },
405 { .name = "dac121c081", .driver_data = (kernel_ulong_t)&dac5571_spec[single_12bit] },
406 { .name = "dac5571", .driver_data = (kernel_ulong_t)&dac5571_spec[single_8bit] },
407 { .name = "dac6571", .driver_data = (kernel_ulong_t)&dac5571_spec[single_10bit] },
408 { .name = "dac7571", .driver_data = (kernel_ulong_t)&dac5571_spec[single_12bit] },
409 { .name = "dac5574", .driver_data = (kernel_ulong_t)&dac5571_spec[quad_8bit] },
410 { .name = "dac6574", .driver_data = (kernel_ulong_t)&dac5571_spec[quad_10bit] },
411 { .name = "dac7574", .driver_data = (kernel_ulong_t)&dac5571_spec[quad_12bit] },
412 { .name = "dac5573", .driver_data = (kernel_ulong_t)&dac5571_spec[quad_8bit] },
413 { .name = "dac6573", .driver_data = (kernel_ulong_t)&dac5571_spec[quad_10bit] },
414 { .name = "dac7573", .driver_data = (kernel_ulong_t)&dac5571_spec[quad_12bit] },
415 { }
416 };
417 MODULE_DEVICE_TABLE(i2c, dac5571_id);
418
419 static struct i2c_driver dac5571_driver = {
420 .driver = {
421 .name = "ti-dac5571",
422 .of_match_table = dac5571_of_id,
423 },
424 .probe = dac5571_probe,
425 .remove = dac5571_remove,
426 .id_table = dac5571_id,
427 };
428 module_i2c_driver(dac5571_driver);
429
430 MODULE_AUTHOR("Sean Nyekjaer <sean@geanix.dk>");
431 MODULE_DESCRIPTION("Texas Instruments 8/10/12-bit 1/4-channel DAC driver");
432 MODULE_LICENSE("GPL v2");
433