1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * AD7606 SPI ADC driver
4 *
5 * Copyright 2011 Analog Devices Inc.
6 */
7
8 #include <linux/err.h>
9 #include <linux/module.h>
10 #include <linux/spi/spi.h>
11 #include <linux/types.h>
12
13 #include <linux/iio/iio.h>
14 #include "ad7606.h"
15
16 #define MAX_SPI_FREQ_HZ 23500000 /* VDRIVE above 4.75 V */
17
18 #define AD7616_CONFIGURATION_REGISTER 0x02
19 #define AD7616_OS_MASK GENMASK(4, 2)
20 #define AD7616_BURST_MODE BIT(6)
21 #define AD7616_SEQEN_MODE BIT(5)
22 #define AD7616_RANGE_CH_A_ADDR_OFF 0x04
23 #define AD7616_RANGE_CH_B_ADDR_OFF 0x06
24 /*
25 * Range of channels from a group are stored in 2 registers.
26 * 0, 1, 2, 3 in a register followed by 4, 5, 6, 7 in second register.
27 * For channels from second group(8-15) the order is the same, only with
28 * an offset of 2 for register address.
29 */
30 #define AD7616_RANGE_CH_ADDR(ch) ((ch) >> 2)
31 /* The range of the channel is stored in 2 bits */
32 #define AD7616_RANGE_CH_MSK(ch) (0b11 << (((ch) & 0b11) * 2))
33 #define AD7616_RANGE_CH_MODE(ch, mode) ((mode) << ((((ch) & 0b11)) * 2))
34
35 #define AD7606_CONFIGURATION_REGISTER 0x02
36 #define AD7606_SINGLE_DOUT 0x00
37
38 /*
39 * Range for AD7606B channels are stored in registers starting with address 0x3.
40 * Each register stores range for 2 channels(4 bits per channel).
41 */
42 #define AD7606_RANGE_CH_MSK(ch) (GENMASK(3, 0) << (4 * ((ch) & 0x1)))
43 #define AD7606_RANGE_CH_MODE(ch, mode) \
44 ((GENMASK(3, 0) & mode) << (4 * ((ch) & 0x1)))
45 #define AD7606_RANGE_CH_ADDR(ch) (0x03 + ((ch) >> 1))
46 #define AD7606_OS_MODE 0x08
47
48 static const struct iio_chan_spec ad7616_sw_channels[] = {
49 IIO_CHAN_SOFT_TIMESTAMP(16),
50 AD7616_CHANNEL(0),
51 AD7616_CHANNEL(1),
52 AD7616_CHANNEL(2),
53 AD7616_CHANNEL(3),
54 AD7616_CHANNEL(4),
55 AD7616_CHANNEL(5),
56 AD7616_CHANNEL(6),
57 AD7616_CHANNEL(7),
58 AD7616_CHANNEL(8),
59 AD7616_CHANNEL(9),
60 AD7616_CHANNEL(10),
61 AD7616_CHANNEL(11),
62 AD7616_CHANNEL(12),
63 AD7616_CHANNEL(13),
64 AD7616_CHANNEL(14),
65 AD7616_CHANNEL(15),
66 };
67
68 static const struct iio_chan_spec ad7606b_sw_channels[] = {
69 IIO_CHAN_SOFT_TIMESTAMP(8),
70 AD7606_SW_CHANNEL(0, 16),
71 AD7606_SW_CHANNEL(1, 16),
72 AD7606_SW_CHANNEL(2, 16),
73 AD7606_SW_CHANNEL(3, 16),
74 AD7606_SW_CHANNEL(4, 16),
75 AD7606_SW_CHANNEL(5, 16),
76 AD7606_SW_CHANNEL(6, 16),
77 AD7606_SW_CHANNEL(7, 16),
78 };
79
80 static const struct iio_chan_spec ad7606c_18_sw_channels[] = {
81 IIO_CHAN_SOFT_TIMESTAMP(8),
82 AD7606_SW_CHANNEL(0, 18),
83 AD7606_SW_CHANNEL(1, 18),
84 AD7606_SW_CHANNEL(2, 18),
85 AD7606_SW_CHANNEL(3, 18),
86 AD7606_SW_CHANNEL(4, 18),
87 AD7606_SW_CHANNEL(5, 18),
88 AD7606_SW_CHANNEL(6, 18),
89 AD7606_SW_CHANNEL(7, 18),
90 };
91
92 static const unsigned int ad7606B_oversampling_avail[9] = {
93 1, 2, 4, 8, 16, 32, 64, 128, 256
94 };
95
ad7616_spi_rd_wr_cmd(int addr,char isWriteOp)96 static u16 ad7616_spi_rd_wr_cmd(int addr, char isWriteOp)
97 {
98 /*
99 * The address of register consist of one w/r bit
100 * 6 bits of address followed by one reserved bit.
101 */
102 return ((addr & 0x7F) << 1) | ((isWriteOp & 0x1) << 7);
103 }
104
ad7606B_spi_rd_wr_cmd(int addr,char is_write_op)105 static u16 ad7606B_spi_rd_wr_cmd(int addr, char is_write_op)
106 {
107 /*
108 * The address of register consists of one bit which
109 * specifies a read command placed in bit 6, followed by
110 * 6 bits of address.
111 */
112 return (addr & 0x3F) | (((~is_write_op) & 0x1) << 6);
113 }
114
ad7606_spi_read_block(struct device * dev,int count,void * buf)115 static int ad7606_spi_read_block(struct device *dev,
116 int count, void *buf)
117 {
118 struct spi_device *spi = to_spi_device(dev);
119 int i, ret;
120 unsigned short *data = buf;
121 __be16 *bdata = buf;
122
123 ret = spi_read(spi, buf, count * 2);
124 if (ret < 0) {
125 dev_err(&spi->dev, "SPI read error\n");
126 return ret;
127 }
128
129 for (i = 0; i < count; i++)
130 data[i] = be16_to_cpu(bdata[i]);
131
132 return 0;
133 }
134
ad7606_spi_read_block14to16(struct device * dev,int count,void * buf)135 static int ad7606_spi_read_block14to16(struct device *dev,
136 int count, void *buf)
137 {
138 struct spi_device *spi = to_spi_device(dev);
139 struct spi_transfer xfer = {
140 .bits_per_word = 14,
141 .len = count * sizeof(u16),
142 .rx_buf = buf,
143 };
144
145 return spi_sync_transfer(spi, &xfer, 1);
146 }
147
ad7606_spi_read_block18to32(struct device * dev,int count,void * buf)148 static int ad7606_spi_read_block18to32(struct device *dev,
149 int count, void *buf)
150 {
151 struct spi_device *spi = to_spi_device(dev);
152 struct spi_transfer xfer = {
153 .bits_per_word = 18,
154 .len = count * sizeof(u32),
155 .rx_buf = buf,
156 };
157
158 return spi_sync_transfer(spi, &xfer, 1);
159 }
160
ad7606_spi_reg_read(struct ad7606_state * st,unsigned int addr)161 static int ad7606_spi_reg_read(struct ad7606_state *st, unsigned int addr)
162 {
163 struct spi_device *spi = to_spi_device(st->dev);
164 struct spi_transfer t[] = {
165 {
166 .tx_buf = &st->d16[0],
167 .len = 2,
168 .cs_change = 0,
169 }, {
170 .rx_buf = &st->d16[1],
171 .len = 2,
172 },
173 };
174 int ret;
175
176 st->d16[0] = cpu_to_be16(st->bops->rd_wr_cmd(addr, 0) << 8);
177
178 ret = spi_sync_transfer(spi, t, ARRAY_SIZE(t));
179 if (ret < 0)
180 return ret;
181
182 return be16_to_cpu(st->d16[1]);
183 }
184
ad7606_spi_reg_write(struct ad7606_state * st,unsigned int addr,unsigned int val)185 static int ad7606_spi_reg_write(struct ad7606_state *st,
186 unsigned int addr,
187 unsigned int val)
188 {
189 struct spi_device *spi = to_spi_device(st->dev);
190
191 st->d16[0] = cpu_to_be16((st->bops->rd_wr_cmd(addr, 1) << 8) |
192 (val & 0x1FF));
193
194 return spi_write(spi, &st->d16[0], sizeof(st->d16[0]));
195 }
196
ad7606_spi_write_mask(struct ad7606_state * st,unsigned int addr,unsigned long mask,unsigned int val)197 static int ad7606_spi_write_mask(struct ad7606_state *st,
198 unsigned int addr,
199 unsigned long mask,
200 unsigned int val)
201 {
202 int readval;
203
204 readval = st->bops->reg_read(st, addr);
205 if (readval < 0)
206 return readval;
207
208 readval &= ~mask;
209 readval |= val;
210
211 return st->bops->reg_write(st, addr, readval);
212 }
213
ad7616_write_scale_sw(struct iio_dev * indio_dev,int ch,int val)214 static int ad7616_write_scale_sw(struct iio_dev *indio_dev, int ch, int val)
215 {
216 struct ad7606_state *st = iio_priv(indio_dev);
217 unsigned int ch_addr, mode, ch_index;
218
219
220 /*
221 * Ad7616 has 16 channels divided in group A and group B.
222 * The range of channels from A are stored in registers with address 4
223 * while channels from B are stored in register with address 6.
224 * The last bit from channels determines if it is from group A or B
225 * because the order of channels in iio is 0A, 0B, 1A, 1B...
226 */
227 ch_index = ch >> 1;
228
229 ch_addr = AD7616_RANGE_CH_ADDR(ch_index);
230
231 if ((ch & 0x1) == 0) /* channel A */
232 ch_addr += AD7616_RANGE_CH_A_ADDR_OFF;
233 else /* channel B */
234 ch_addr += AD7616_RANGE_CH_B_ADDR_OFF;
235
236 /* 0b01 for 2.5v, 0b10 for 5v and 0b11 for 10v */
237 mode = AD7616_RANGE_CH_MODE(ch_index, ((val + 1) & 0b11));
238 return st->bops->write_mask(st, ch_addr, AD7616_RANGE_CH_MSK(ch_index),
239 mode);
240 }
241
ad7616_write_os_sw(struct iio_dev * indio_dev,int val)242 static int ad7616_write_os_sw(struct iio_dev *indio_dev, int val)
243 {
244 struct ad7606_state *st = iio_priv(indio_dev);
245
246 return st->bops->write_mask(st, AD7616_CONFIGURATION_REGISTER,
247 AD7616_OS_MASK, val << 2);
248 }
249
ad7606_write_scale_sw(struct iio_dev * indio_dev,int ch,int val)250 static int ad7606_write_scale_sw(struct iio_dev *indio_dev, int ch, int val)
251 {
252 struct ad7606_state *st = iio_priv(indio_dev);
253
254 return ad7606_spi_write_mask(st,
255 AD7606_RANGE_CH_ADDR(ch),
256 AD7606_RANGE_CH_MSK(ch),
257 AD7606_RANGE_CH_MODE(ch, val));
258 }
259
ad7606_write_os_sw(struct iio_dev * indio_dev,int val)260 static int ad7606_write_os_sw(struct iio_dev *indio_dev, int val)
261 {
262 struct ad7606_state *st = iio_priv(indio_dev);
263
264 return ad7606_spi_reg_write(st, AD7606_OS_MODE, val);
265 }
266
ad7616_sw_mode_config(struct iio_dev * indio_dev)267 static int ad7616_sw_mode_config(struct iio_dev *indio_dev)
268 {
269 struct ad7606_state *st = iio_priv(indio_dev);
270
271 /*
272 * Scale can be configured individually for each channel
273 * in software mode.
274 */
275 indio_dev->channels = ad7616_sw_channels;
276
277 st->write_scale = ad7616_write_scale_sw;
278 st->write_os = &ad7616_write_os_sw;
279
280 /* Activate Burst mode and SEQEN MODE */
281 return st->bops->write_mask(st,
282 AD7616_CONFIGURATION_REGISTER,
283 AD7616_BURST_MODE | AD7616_SEQEN_MODE,
284 AD7616_BURST_MODE | AD7616_SEQEN_MODE);
285 }
286
ad7606B_sw_mode_config(struct iio_dev * indio_dev)287 static int ad7606B_sw_mode_config(struct iio_dev *indio_dev)
288 {
289 struct ad7606_state *st = iio_priv(indio_dev);
290 DECLARE_BITMAP(os, 3);
291
292 bitmap_fill(os, 3);
293 /*
294 * Software mode is enabled when all three oversampling
295 * pins are set to high. If oversampling gpios are defined
296 * in the device tree, then they need to be set to high,
297 * otherwise, they must be hardwired to VDD
298 */
299 if (st->gpio_os) {
300 gpiod_set_array_value(st->gpio_os->ndescs,
301 st->gpio_os->desc, st->gpio_os->info, os);
302 }
303 /* OS of 128 and 256 are available only in software mode */
304 st->oversampling_avail = ad7606B_oversampling_avail;
305 st->num_os_ratios = ARRAY_SIZE(ad7606B_oversampling_avail);
306
307 st->write_scale = ad7606_write_scale_sw;
308 st->write_os = &ad7606_write_os_sw;
309
310 /* Configure device spi to output on a single channel */
311 st->bops->reg_write(st,
312 AD7606_CONFIGURATION_REGISTER,
313 AD7606_SINGLE_DOUT);
314
315 /*
316 * Scale can be configured individually for each channel
317 * in software mode.
318 */
319 indio_dev->channels = ad7606b_sw_channels;
320
321 return 0;
322 }
323
ad7606c_18_sw_mode_config(struct iio_dev * indio_dev)324 static int ad7606c_18_sw_mode_config(struct iio_dev *indio_dev)
325 {
326 int ret;
327
328 ret = ad7606B_sw_mode_config(indio_dev);
329 if (ret)
330 return ret;
331
332 indio_dev->channels = ad7606c_18_sw_channels;
333
334 return 0;
335 }
336
337 static const struct ad7606_bus_ops ad7606_spi_bops = {
338 .read_block = ad7606_spi_read_block,
339 };
340
341 static const struct ad7606_bus_ops ad7607_spi_bops = {
342 .read_block = ad7606_spi_read_block14to16,
343 };
344
345 static const struct ad7606_bus_ops ad7608_spi_bops = {
346 .read_block = ad7606_spi_read_block18to32,
347 };
348
349 static const struct ad7606_bus_ops ad7616_spi_bops = {
350 .read_block = ad7606_spi_read_block,
351 .reg_read = ad7606_spi_reg_read,
352 .reg_write = ad7606_spi_reg_write,
353 .write_mask = ad7606_spi_write_mask,
354 .rd_wr_cmd = ad7616_spi_rd_wr_cmd,
355 .sw_mode_config = ad7616_sw_mode_config,
356 };
357
358 static const struct ad7606_bus_ops ad7606b_spi_bops = {
359 .read_block = ad7606_spi_read_block,
360 .reg_read = ad7606_spi_reg_read,
361 .reg_write = ad7606_spi_reg_write,
362 .write_mask = ad7606_spi_write_mask,
363 .rd_wr_cmd = ad7606B_spi_rd_wr_cmd,
364 .sw_mode_config = ad7606B_sw_mode_config,
365 };
366
367 static const struct ad7606_bus_ops ad7606c_18_spi_bops = {
368 .read_block = ad7606_spi_read_block18to32,
369 .reg_read = ad7606_spi_reg_read,
370 .reg_write = ad7606_spi_reg_write,
371 .write_mask = ad7606_spi_write_mask,
372 .rd_wr_cmd = ad7606B_spi_rd_wr_cmd,
373 .sw_mode_config = ad7606c_18_sw_mode_config,
374 };
375
376 static const struct ad7606_bus_info ad7605_4_bus_info = {
377 .chip_info = &ad7605_4_info,
378 .bops = &ad7606_spi_bops,
379 };
380
381 static const struct ad7606_bus_info ad7606_8_bus_info = {
382 .chip_info = &ad7606_8_info,
383 .bops = &ad7606_spi_bops,
384 };
385
386 static const struct ad7606_bus_info ad7606_6_bus_info = {
387 .chip_info = &ad7606_6_info,
388 .bops = &ad7606_spi_bops,
389 };
390
391 static const struct ad7606_bus_info ad7606_4_bus_info = {
392 .chip_info = &ad7606_4_info,
393 .bops = &ad7606_spi_bops,
394 };
395
396 static const struct ad7606_bus_info ad7606b_bus_info = {
397 .chip_info = &ad7606b_info,
398 .bops = &ad7606b_spi_bops,
399 };
400
401 static const struct ad7606_bus_info ad7606c_16_bus_info = {
402 .chip_info = &ad7606c_16_info,
403 .bops = &ad7606b_spi_bops,
404 };
405
406 static const struct ad7606_bus_info ad7606c_18_bus_info = {
407 .chip_info = &ad7606c_18_info,
408 .bops = &ad7606c_18_spi_bops,
409 };
410
411 static const struct ad7606_bus_info ad7607_bus_info = {
412 .chip_info = &ad7607_info,
413 .bops = &ad7607_spi_bops,
414 };
415
416 static const struct ad7606_bus_info ad7608_bus_info = {
417 .chip_info = &ad7608_info,
418 .bops = &ad7608_spi_bops,
419 };
420
421 static const struct ad7606_bus_info ad7609_bus_info = {
422 .chip_info = &ad7609_info,
423 .bops = &ad7608_spi_bops,
424 };
425
426 static const struct ad7606_bus_info ad7616_bus_info = {
427 .chip_info = &ad7616_info,
428 .bops = &ad7616_spi_bops,
429 };
430
ad7606_spi_probe(struct spi_device * spi)431 static int ad7606_spi_probe(struct spi_device *spi)
432 {
433 const struct ad7606_bus_info *bus_info = spi_get_device_match_data(spi);
434
435 return ad7606_probe(&spi->dev, spi->irq, NULL,
436 bus_info->chip_info, bus_info->bops);
437 }
438
439 static const struct spi_device_id ad7606_id_table[] = {
440 { "ad7605-4", (kernel_ulong_t)&ad7605_4_bus_info },
441 { "ad7606-4", (kernel_ulong_t)&ad7606_4_bus_info },
442 { "ad7606-6", (kernel_ulong_t)&ad7606_6_bus_info },
443 { "ad7606-8", (kernel_ulong_t)&ad7606_8_bus_info },
444 { "ad7606b", (kernel_ulong_t)&ad7606b_bus_info },
445 { "ad7606c-16", (kernel_ulong_t)&ad7606c_16_bus_info },
446 { "ad7606c-18", (kernel_ulong_t)&ad7606c_18_bus_info },
447 { "ad7607", (kernel_ulong_t)&ad7607_bus_info },
448 { "ad7608", (kernel_ulong_t)&ad7608_bus_info },
449 { "ad7609", (kernel_ulong_t)&ad7609_bus_info },
450 { "ad7616", (kernel_ulong_t)&ad7616_bus_info },
451 { }
452 };
453 MODULE_DEVICE_TABLE(spi, ad7606_id_table);
454
455 static const struct of_device_id ad7606_of_match[] = {
456 { .compatible = "adi,ad7605-4", .data = &ad7605_4_bus_info },
457 { .compatible = "adi,ad7606-4", .data = &ad7606_4_bus_info },
458 { .compatible = "adi,ad7606-6", .data = &ad7606_6_bus_info },
459 { .compatible = "adi,ad7606-8", .data = &ad7606_8_bus_info },
460 { .compatible = "adi,ad7606b", .data = &ad7606b_bus_info },
461 { .compatible = "adi,ad7606c-16", .data = &ad7606c_16_bus_info },
462 { .compatible = "adi,ad7606c-18", .data = &ad7606c_18_bus_info },
463 { .compatible = "adi,ad7607", .data = &ad7607_bus_info },
464 { .compatible = "adi,ad7608", .data = &ad7608_bus_info },
465 { .compatible = "adi,ad7609", .data = &ad7609_bus_info },
466 { .compatible = "adi,ad7616", .data = &ad7616_bus_info },
467 { }
468 };
469 MODULE_DEVICE_TABLE(of, ad7606_of_match);
470
471 static struct spi_driver ad7606_driver = {
472 .driver = {
473 .name = "ad7606",
474 .of_match_table = ad7606_of_match,
475 .pm = AD7606_PM_OPS,
476 },
477 .probe = ad7606_spi_probe,
478 .id_table = ad7606_id_table,
479 };
480 module_spi_driver(ad7606_driver);
481
482 MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
483 MODULE_DESCRIPTION("Analog Devices AD7606 ADC");
484 MODULE_LICENSE("GPL v2");
485 MODULE_IMPORT_NS("IIO_AD7606");
486