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-rw-r--r--drivers/iio/dac/ad5686.c418
1 files changed, 418 insertions, 0 deletions
diff --git a/drivers/iio/dac/ad5686.c b/drivers/iio/dac/ad5686.c
new file mode 100644
index 000000000000..6948d75e1036
--- /dev/null
+++ b/drivers/iio/dac/ad5686.c
@@ -0,0 +1,418 @@
1/*
2 * AD5686R, AD5685R, AD5684R Digital to analog converters driver
3 *
4 * Copyright 2011 Analog Devices Inc.
5 *
6 * Licensed under the GPL-2.
7 */
8
9#include <linux/interrupt.h>
10#include <linux/fs.h>
11#include <linux/device.h>
12#include <linux/module.h>
13#include <linux/kernel.h>
14#include <linux/spi/spi.h>
15#include <linux/slab.h>
16#include <linux/sysfs.h>
17#include <linux/regulator/consumer.h>
18
19#include <linux/iio/iio.h>
20#include <linux/iio/sysfs.h>
21
22#define AD5686_DAC_CHANNELS 4
23
24#define AD5686_ADDR(x) ((x) << 16)
25#define AD5686_CMD(x) ((x) << 20)
26
27#define AD5686_ADDR_DAC(chan) (0x1 << (chan))
28#define AD5686_ADDR_ALL_DAC 0xF
29
30#define AD5686_CMD_NOOP 0x0
31#define AD5686_CMD_WRITE_INPUT_N 0x1
32#define AD5686_CMD_UPDATE_DAC_N 0x2
33#define AD5686_CMD_WRITE_INPUT_N_UPDATE_N 0x3
34#define AD5686_CMD_POWERDOWN_DAC 0x4
35#define AD5686_CMD_LDAC_MASK 0x5
36#define AD5686_CMD_RESET 0x6
37#define AD5686_CMD_INTERNAL_REFER_SETUP 0x7
38#define AD5686_CMD_DAISY_CHAIN_ENABLE 0x8
39#define AD5686_CMD_READBACK_ENABLE 0x9
40
41#define AD5686_LDAC_PWRDN_NONE 0x0
42#define AD5686_LDAC_PWRDN_1K 0x1
43#define AD5686_LDAC_PWRDN_100K 0x2
44#define AD5686_LDAC_PWRDN_3STATE 0x3
45
46/**
47 * struct ad5686_chip_info - chip specific information
48 * @int_vref_mv: AD5620/40/60: the internal reference voltage
49 * @channel: channel specification
50*/
51
52struct ad5686_chip_info {
53 u16 int_vref_mv;
54 struct iio_chan_spec channel[AD5686_DAC_CHANNELS];
55};
56
57/**
58 * struct ad5446_state - driver instance specific data
59 * @spi: spi_device
60 * @chip_info: chip model specific constants, available modes etc
61 * @reg: supply regulator
62 * @vref_mv: actual reference voltage used
63 * @pwr_down_mask: power down mask
64 * @pwr_down_mode: current power down mode
65 * @data: spi transfer buffers
66 */
67
68struct ad5686_state {
69 struct spi_device *spi;
70 const struct ad5686_chip_info *chip_info;
71 struct regulator *reg;
72 unsigned short vref_mv;
73 unsigned pwr_down_mask;
74 unsigned pwr_down_mode;
75 /*
76 * DMA (thus cache coherency maintenance) requires the
77 * transfer buffers to live in their own cache lines.
78 */
79
80 union {
81 u32 d32;
82 u8 d8[4];
83 } data[3] ____cacheline_aligned;
84};
85
86/**
87 * ad5686_supported_device_ids:
88 */
89
90enum ad5686_supported_device_ids {
91 ID_AD5684,
92 ID_AD5685,
93 ID_AD5686,
94};
95static int ad5686_spi_write(struct ad5686_state *st,
96 u8 cmd, u8 addr, u16 val, u8 shift)
97{
98 val <<= shift;
99
100 st->data[0].d32 = cpu_to_be32(AD5686_CMD(cmd) |
101 AD5686_ADDR(addr) |
102 val);
103
104 return spi_write(st->spi, &st->data[0].d8[1], 3);
105}
106
107static int ad5686_spi_read(struct ad5686_state *st, u8 addr)
108{
109 struct spi_transfer t[] = {
110 {
111 .tx_buf = &st->data[0].d8[1],
112 .len = 3,
113 .cs_change = 1,
114 }, {
115 .tx_buf = &st->data[1].d8[1],
116 .rx_buf = &st->data[2].d8[1],
117 .len = 3,
118 },
119 };
120 struct spi_message m;
121 int ret;
122
123 spi_message_init(&m);
124 spi_message_add_tail(&t[0], &m);
125 spi_message_add_tail(&t[1], &m);
126
127 st->data[0].d32 = cpu_to_be32(AD5686_CMD(AD5686_CMD_READBACK_ENABLE) |
128 AD5686_ADDR(addr));
129 st->data[1].d32 = cpu_to_be32(AD5686_CMD(AD5686_CMD_NOOP));
130
131 ret = spi_sync(st->spi, &m);
132 if (ret < 0)
133 return ret;
134
135 return be32_to_cpu(st->data[2].d32);
136}
137
138static const char * const ad5686_powerdown_modes[] = {
139 "1kohm_to_gnd",
140 "100kohm_to_gnd",
141 "three_state"
142};
143
144static int ad5686_get_powerdown_mode(struct iio_dev *indio_dev,
145 const struct iio_chan_spec *chan)
146{
147 struct ad5686_state *st = iio_priv(indio_dev);
148
149 return ((st->pwr_down_mode >> (chan->channel * 2)) & 0x3) - 1;
150}
151
152static int ad5686_set_powerdown_mode(struct iio_dev *indio_dev,
153 const struct iio_chan_spec *chan, unsigned int mode)
154{
155 struct ad5686_state *st = iio_priv(indio_dev);
156
157 st->pwr_down_mode &= ~(0x3 << (chan->channel * 2));
158 st->pwr_down_mode |= ((mode + 1) << (chan->channel * 2));
159
160 return 0;
161}
162
163static const struct iio_enum ad5686_powerdown_mode_enum = {
164 .items = ad5686_powerdown_modes,
165 .num_items = ARRAY_SIZE(ad5686_powerdown_modes),
166 .get = ad5686_get_powerdown_mode,
167 .set = ad5686_set_powerdown_mode,
168};
169
170static ssize_t ad5686_read_dac_powerdown(struct iio_dev *indio_dev,
171 uintptr_t private, const struct iio_chan_spec *chan, char *buf)
172{
173 struct ad5686_state *st = iio_priv(indio_dev);
174
175 return sprintf(buf, "%d\n", !!(st->pwr_down_mask &
176 (0x3 << (chan->channel * 2))));
177}
178
179static ssize_t ad5686_write_dac_powerdown(struct iio_dev *indio_dev,
180 uintptr_t private, const struct iio_chan_spec *chan, const char *buf,
181 size_t len)
182{
183 bool readin;
184 int ret;
185 struct ad5686_state *st = iio_priv(indio_dev);
186
187 ret = strtobool(buf, &readin);
188 if (ret)
189 return ret;
190
191 if (readin == true)
192 st->pwr_down_mask |= (0x3 << (chan->channel * 2));
193 else
194 st->pwr_down_mask &= ~(0x3 << (chan->channel * 2));
195
196 ret = ad5686_spi_write(st, AD5686_CMD_POWERDOWN_DAC, 0,
197 st->pwr_down_mask & st->pwr_down_mode, 0);
198
199 return ret ? ret : len;
200}
201
202static int ad5686_read_raw(struct iio_dev *indio_dev,
203 struct iio_chan_spec const *chan,
204 int *val,
205 int *val2,
206 long m)
207{
208 struct ad5686_state *st = iio_priv(indio_dev);
209 unsigned long scale_uv;
210 int ret;
211
212 switch (m) {
213 case IIO_CHAN_INFO_RAW:
214 mutex_lock(&indio_dev->mlock);
215 ret = ad5686_spi_read(st, chan->address);
216 mutex_unlock(&indio_dev->mlock);
217 if (ret < 0)
218 return ret;
219 *val = ret;
220 return IIO_VAL_INT;
221 break;
222 case IIO_CHAN_INFO_SCALE:
223 scale_uv = (st->vref_mv * 100000)
224 >> (chan->scan_type.realbits);
225 *val = scale_uv / 100000;
226 *val2 = (scale_uv % 100000) * 10;
227 return IIO_VAL_INT_PLUS_MICRO;
228
229 }
230 return -EINVAL;
231}
232
233static int ad5686_write_raw(struct iio_dev *indio_dev,
234 struct iio_chan_spec const *chan,
235 int val,
236 int val2,
237 long mask)
238{
239 struct ad5686_state *st = iio_priv(indio_dev);
240 int ret;
241
242 switch (mask) {
243 case IIO_CHAN_INFO_RAW:
244 if (val > (1 << chan->scan_type.realbits) || val < 0)
245 return -EINVAL;
246
247 mutex_lock(&indio_dev->mlock);
248 ret = ad5686_spi_write(st,
249 AD5686_CMD_WRITE_INPUT_N_UPDATE_N,
250 chan->address,
251 val,
252 chan->scan_type.shift);
253 mutex_unlock(&indio_dev->mlock);
254 break;
255 default:
256 ret = -EINVAL;
257 }
258
259 return ret;
260}
261
262static const struct iio_info ad5686_info = {
263 .read_raw = ad5686_read_raw,
264 .write_raw = ad5686_write_raw,
265 .driver_module = THIS_MODULE,
266};
267
268static const struct iio_chan_spec_ext_info ad5686_ext_info[] = {
269 {
270 .name = "powerdown",
271 .read = ad5686_read_dac_powerdown,
272 .write = ad5686_write_dac_powerdown,
273 },
274 IIO_ENUM("powerdown_mode", false, &ad5686_powerdown_mode_enum),
275 IIO_ENUM_AVAILABLE("powerdown_mode", &ad5686_powerdown_mode_enum),
276 { },
277};
278
279#define AD5868_CHANNEL(chan, bits, shift) { \
280 .type = IIO_VOLTAGE, \
281 .indexed = 1, \
282 .output = 1, \
283 .channel = chan, \
284 .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT | \
285 IIO_CHAN_INFO_SCALE_SHARED_BIT, \
286 .address = AD5686_ADDR_DAC(chan), \
287 .scan_type = IIO_ST('u', bits, 16, shift), \
288 .ext_info = ad5686_ext_info, \
289}
290
291static const struct ad5686_chip_info ad5686_chip_info_tbl[] = {
292 [ID_AD5684] = {
293 .channel[0] = AD5868_CHANNEL(0, 12, 4),
294 .channel[1] = AD5868_CHANNEL(1, 12, 4),
295 .channel[2] = AD5868_CHANNEL(2, 12, 4),
296 .channel[3] = AD5868_CHANNEL(3, 12, 4),
297 .int_vref_mv = 2500,
298 },
299 [ID_AD5685] = {
300 .channel[0] = AD5868_CHANNEL(0, 14, 2),
301 .channel[1] = AD5868_CHANNEL(1, 14, 2),
302 .channel[2] = AD5868_CHANNEL(2, 14, 2),
303 .channel[3] = AD5868_CHANNEL(3, 14, 2),
304 .int_vref_mv = 2500,
305 },
306 [ID_AD5686] = {
307 .channel[0] = AD5868_CHANNEL(0, 16, 0),
308 .channel[1] = AD5868_CHANNEL(1, 16, 0),
309 .channel[2] = AD5868_CHANNEL(2, 16, 0),
310 .channel[3] = AD5868_CHANNEL(3, 16, 0),
311 .int_vref_mv = 2500,
312 },
313};
314
315
316static int __devinit ad5686_probe(struct spi_device *spi)
317{
318 struct ad5686_state *st;
319 struct iio_dev *indio_dev;
320 int ret, regdone = 0, voltage_uv = 0;
321
322 indio_dev = iio_device_alloc(sizeof(*st));
323 if (indio_dev == NULL)
324 return -ENOMEM;
325
326 st = iio_priv(indio_dev);
327 spi_set_drvdata(spi, indio_dev);
328
329 st->reg = regulator_get(&spi->dev, "vcc");
330 if (!IS_ERR(st->reg)) {
331 ret = regulator_enable(st->reg);
332 if (ret)
333 goto error_put_reg;
334
335 voltage_uv = regulator_get_voltage(st->reg);
336 }
337
338 st->chip_info =
339 &ad5686_chip_info_tbl[spi_get_device_id(spi)->driver_data];
340
341 if (voltage_uv)
342 st->vref_mv = voltage_uv / 1000;
343 else
344 st->vref_mv = st->chip_info->int_vref_mv;
345
346 st->spi = spi;
347
348 /* Set all the power down mode for all channels to 1K pulldown */
349 st->pwr_down_mode = 0x55;
350
351 indio_dev->dev.parent = &spi->dev;
352 indio_dev->name = spi_get_device_id(spi)->name;
353 indio_dev->info = &ad5686_info;
354 indio_dev->modes = INDIO_DIRECT_MODE;
355 indio_dev->channels = st->chip_info->channel;
356 indio_dev->num_channels = AD5686_DAC_CHANNELS;
357
358 regdone = 1;
359 ret = ad5686_spi_write(st, AD5686_CMD_INTERNAL_REFER_SETUP, 0,
360 !!voltage_uv, 0);
361 if (ret)
362 goto error_disable_reg;
363
364 ret = iio_device_register(indio_dev);
365 if (ret)
366 goto error_disable_reg;
367
368 return 0;
369
370error_disable_reg:
371 if (!IS_ERR(st->reg))
372 regulator_disable(st->reg);
373error_put_reg:
374 if (!IS_ERR(st->reg))
375 regulator_put(st->reg);
376
377 iio_device_free(indio_dev);
378
379 return ret;
380}
381
382static int __devexit ad5686_remove(struct spi_device *spi)
383{
384 struct iio_dev *indio_dev = spi_get_drvdata(spi);
385 struct ad5686_state *st = iio_priv(indio_dev);
386
387 iio_device_unregister(indio_dev);
388 if (!IS_ERR(st->reg)) {
389 regulator_disable(st->reg);
390 regulator_put(st->reg);
391 }
392 iio_device_free(indio_dev);
393
394 return 0;
395}
396
397static const struct spi_device_id ad5686_id[] = {
398 {"ad5684", ID_AD5684},
399 {"ad5685", ID_AD5685},
400 {"ad5686", ID_AD5686},
401 {}
402};
403MODULE_DEVICE_TABLE(spi, ad5686_id);
404
405static struct spi_driver ad5686_driver = {
406 .driver = {
407 .name = "ad5686",
408 .owner = THIS_MODULE,
409 },
410 .probe = ad5686_probe,
411 .remove = __devexit_p(ad5686_remove),
412 .id_table = ad5686_id,
413};
414module_spi_driver(ad5686_driver);
415
416MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
417MODULE_DESCRIPTION("Analog Devices AD5686/85/84 DAC");
418MODULE_LICENSE("GPL v2");
generated by cgit v1.2.2 (git 2.25.0) at 2024-12-19 13:18:55 -0500