2 * AD5760, AD5780, AD5781, AD5790, AD5791 Voltage Output Digital to Analog
5 * Copyright 2011 Analog Devices Inc.
7 * Licensed under the GPL-2.
10 #include <linux/interrupt.h>
12 #include <linux/device.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 #include <linux/module.h>
20 #include <linux/iio/iio.h>
21 #include <linux/iio/sysfs.h>
22 #include <linux/iio/dac/ad5791.h>
24 #define AD5791_RES_MASK(x) ((1 << (x)) - 1)
25 #define AD5791_DAC_MASK AD5791_RES_MASK(20)
26 #define AD5791_DAC_MSB (1 << 19)
28 #define AD5791_CMD_READ (1 << 23)
29 #define AD5791_CMD_WRITE (0 << 23)
30 #define AD5791_ADDR(addr) ((addr) << 20)
33 #define AD5791_ADDR_NOOP 0
34 #define AD5791_ADDR_DAC0 1
35 #define AD5791_ADDR_CTRL 2
36 #define AD5791_ADDR_CLRCODE 3
37 #define AD5791_ADDR_SW_CTRL 4
39 /* Control Register */
40 #define AD5791_CTRL_RBUF (1 << 1)
41 #define AD5791_CTRL_OPGND (1 << 2)
42 #define AD5791_CTRL_DACTRI (1 << 3)
43 #define AD5791_CTRL_BIN2SC (1 << 4)
44 #define AD5791_CTRL_SDODIS (1 << 5)
45 #define AD5761_CTRL_LINCOMP(x) ((x) << 6)
47 #define AD5791_LINCOMP_0_10 0
48 #define AD5791_LINCOMP_10_12 1
49 #define AD5791_LINCOMP_12_16 2
50 #define AD5791_LINCOMP_16_19 3
51 #define AD5791_LINCOMP_19_20 12
53 #define AD5780_LINCOMP_0_10 0
54 #define AD5780_LINCOMP_10_20 12
56 /* Software Control Register */
57 #define AD5791_SWCTRL_LDAC (1 << 0)
58 #define AD5791_SWCTRL_CLR (1 << 1)
59 #define AD5791_SWCTRL_RESET (1 << 2)
61 #define AD5791_DAC_PWRDN_6K 0
62 #define AD5791_DAC_PWRDN_3STATE 1
65 * struct ad5791_chip_info - chip specific information
66 * @get_lin_comp: function pointer to the device specific function
69 struct ad5791_chip_info {
70 int (*get_lin_comp) (unsigned int span);
74 * struct ad5791_state - driver instance specific data
76 * @reg_vdd: positive supply regulator
77 * @reg_vss: negative supply regulator
78 * @chip_info: chip model specific constants
79 * @vref_mv: actual reference voltage used
80 * @vref_neg_mv: voltage of the negative supply
81 * @pwr_down_mode current power down mode
85 struct spi_device *spi;
86 struct regulator *reg_vdd;
87 struct regulator *reg_vss;
88 const struct ad5791_chip_info *chip_info;
89 unsigned short vref_mv;
90 unsigned int vref_neg_mv;
92 unsigned pwr_down_mode;
97 * ad5791_supported_device_ids:
100 enum ad5791_supported_device_ids {
107 static int ad5791_spi_write(struct spi_device *spi, u8 addr, u32 val)
114 data.d32 = cpu_to_be32(AD5791_CMD_WRITE |
116 (val & AD5791_DAC_MASK));
118 return spi_write(spi, &data.d8[1], 3);
121 static int ad5791_spi_read(struct spi_device *spi, u8 addr, u32 *val)
128 struct spi_message msg;
129 struct spi_transfer xfers[] = {
131 .tx_buf = &data[0].d8[1],
136 .tx_buf = &data[1].d8[1],
137 .rx_buf = &data[2].d8[1],
143 data[0].d32 = cpu_to_be32(AD5791_CMD_READ |
145 data[1].d32 = cpu_to_be32(AD5791_ADDR(AD5791_ADDR_NOOP));
147 spi_message_init(&msg);
148 spi_message_add_tail(&xfers[0], &msg);
149 spi_message_add_tail(&xfers[1], &msg);
150 ret = spi_sync(spi, &msg);
152 *val = be32_to_cpu(data[2].d32);
157 static const char * const ad5791_powerdown_modes[] = {
162 static int ad5791_get_powerdown_mode(struct iio_dev *indio_dev,
163 const struct iio_chan_spec *chan)
165 struct ad5791_state *st = iio_priv(indio_dev);
167 return st->pwr_down_mode;
170 static int ad5791_set_powerdown_mode(struct iio_dev *indio_dev,
171 const struct iio_chan_spec *chan, unsigned int mode)
173 struct ad5791_state *st = iio_priv(indio_dev);
175 st->pwr_down_mode = mode;
180 static const struct iio_enum ad5791_powerdown_mode_enum = {
181 .items = ad5791_powerdown_modes,
182 .num_items = ARRAY_SIZE(ad5791_powerdown_modes),
183 .get = ad5791_get_powerdown_mode,
184 .set = ad5791_set_powerdown_mode,
187 static ssize_t ad5791_read_dac_powerdown(struct iio_dev *indio_dev,
188 uintptr_t private, const struct iio_chan_spec *chan, char *buf)
190 struct ad5791_state *st = iio_priv(indio_dev);
192 return sprintf(buf, "%d\n", st->pwr_down);
195 static ssize_t ad5791_write_dac_powerdown(struct iio_dev *indio_dev,
196 uintptr_t private, const struct iio_chan_spec *chan, const char *buf,
201 struct ad5791_state *st = iio_priv(indio_dev);
203 ret = strtobool(buf, &pwr_down);
208 st->ctrl &= ~(AD5791_CTRL_OPGND | AD5791_CTRL_DACTRI);
210 if (st->pwr_down_mode == AD5791_DAC_PWRDN_6K)
211 st->ctrl |= AD5791_CTRL_OPGND;
212 else if (st->pwr_down_mode == AD5791_DAC_PWRDN_3STATE)
213 st->ctrl |= AD5791_CTRL_DACTRI;
215 st->pwr_down = pwr_down;
217 ret = ad5791_spi_write(st->spi, AD5791_ADDR_CTRL, st->ctrl);
219 return ret ? ret : len;
222 static int ad5791_get_lin_comp(unsigned int span)
225 return AD5791_LINCOMP_0_10;
226 else if (span <= 12000)
227 return AD5791_LINCOMP_10_12;
228 else if (span <= 16000)
229 return AD5791_LINCOMP_12_16;
230 else if (span <= 19000)
231 return AD5791_LINCOMP_16_19;
233 return AD5791_LINCOMP_19_20;
236 static int ad5780_get_lin_comp(unsigned int span)
239 return AD5780_LINCOMP_0_10;
241 return AD5780_LINCOMP_10_20;
243 static const struct ad5791_chip_info ad5791_chip_info_tbl[] = {
245 .get_lin_comp = ad5780_get_lin_comp,
248 .get_lin_comp = ad5780_get_lin_comp,
251 .get_lin_comp = ad5791_get_lin_comp,
254 .get_lin_comp = ad5791_get_lin_comp,
258 static int ad5791_read_raw(struct iio_dev *indio_dev,
259 struct iio_chan_spec const *chan,
264 struct ad5791_state *st = iio_priv(indio_dev);
269 case IIO_CHAN_INFO_RAW:
270 ret = ad5791_spi_read(st->spi, chan->address, val);
273 *val &= AD5791_DAC_MASK;
274 *val >>= chan->scan_type.shift;
276 case IIO_CHAN_INFO_SCALE:
278 *val2 = (((u64)st->vref_mv) * 1000000ULL) >> chan->scan_type.realbits;
279 return IIO_VAL_INT_PLUS_MICRO;
280 case IIO_CHAN_INFO_OFFSET:
281 val64 = (((u64)st->vref_neg_mv) << chan->scan_type.realbits);
282 do_div(val64, st->vref_mv);
291 static const struct iio_chan_spec_ext_info ad5791_ext_info[] = {
295 .read = ad5791_read_dac_powerdown,
296 .write = ad5791_write_dac_powerdown,
298 IIO_ENUM("powerdown_mode", true, &ad5791_powerdown_mode_enum),
299 IIO_ENUM_AVAILABLE("powerdown_mode", &ad5791_powerdown_mode_enum),
303 #define AD5791_CHAN(bits, shift) { \
304 .type = IIO_VOLTAGE, \
307 .address = AD5791_ADDR_DAC0, \
309 .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT | \
310 IIO_CHAN_INFO_SCALE_SHARED_BIT | \
311 IIO_CHAN_INFO_OFFSET_SHARED_BIT, \
312 .scan_type = IIO_ST('u', bits, 24, shift), \
313 .ext_info = ad5791_ext_info, \
316 static const struct iio_chan_spec ad5791_channels[] = {
317 [ID_AD5760] = AD5791_CHAN(16, 4),
318 [ID_AD5780] = AD5791_CHAN(18, 2),
319 [ID_AD5781] = AD5791_CHAN(18, 2),
320 [ID_AD5791] = AD5791_CHAN(20, 0)
323 static int ad5791_write_raw(struct iio_dev *indio_dev,
324 struct iio_chan_spec const *chan,
329 struct ad5791_state *st = iio_priv(indio_dev);
332 case IIO_CHAN_INFO_RAW:
333 val &= AD5791_RES_MASK(chan->scan_type.realbits);
334 val <<= chan->scan_type.shift;
336 return ad5791_spi_write(st->spi, chan->address, val);
343 static const struct iio_info ad5791_info = {
344 .read_raw = &ad5791_read_raw,
345 .write_raw = &ad5791_write_raw,
346 .driver_module = THIS_MODULE,
349 static int __devinit ad5791_probe(struct spi_device *spi)
351 struct ad5791_platform_data *pdata = spi->dev.platform_data;
352 struct iio_dev *indio_dev;
353 struct ad5791_state *st;
354 int ret, pos_voltage_uv = 0, neg_voltage_uv = 0;
356 indio_dev = iio_device_alloc(sizeof(*st));
357 if (indio_dev == NULL) {
361 st = iio_priv(indio_dev);
362 st->reg_vdd = regulator_get(&spi->dev, "vdd");
363 if (!IS_ERR(st->reg_vdd)) {
364 ret = regulator_enable(st->reg_vdd);
366 goto error_put_reg_pos;
368 pos_voltage_uv = regulator_get_voltage(st->reg_vdd);
371 st->reg_vss = regulator_get(&spi->dev, "vss");
372 if (!IS_ERR(st->reg_vss)) {
373 ret = regulator_enable(st->reg_vss);
375 goto error_put_reg_neg;
377 neg_voltage_uv = regulator_get_voltage(st->reg_vss);
383 if (!IS_ERR(st->reg_vss) && !IS_ERR(st->reg_vdd)) {
384 st->vref_mv = (pos_voltage_uv + neg_voltage_uv) / 1000;
385 st->vref_neg_mv = neg_voltage_uv / 1000;
387 st->vref_mv = pdata->vref_pos_mv + pdata->vref_neg_mv;
388 st->vref_neg_mv = pdata->vref_neg_mv;
390 dev_warn(&spi->dev, "reference voltage unspecified\n");
393 ret = ad5791_spi_write(spi, AD5791_ADDR_SW_CTRL, AD5791_SWCTRL_RESET);
395 goto error_disable_reg_neg;
397 st->chip_info = &ad5791_chip_info_tbl[spi_get_device_id(spi)
401 st->ctrl = AD5761_CTRL_LINCOMP(st->chip_info->get_lin_comp(st->vref_mv))
402 | ((pdata && pdata->use_rbuf_gain2) ? 0 : AD5791_CTRL_RBUF) |
405 ret = ad5791_spi_write(spi, AD5791_ADDR_CTRL, st->ctrl |
406 AD5791_CTRL_OPGND | AD5791_CTRL_DACTRI);
408 goto error_disable_reg_neg;
410 spi_set_drvdata(spi, indio_dev);
411 indio_dev->dev.parent = &spi->dev;
412 indio_dev->info = &ad5791_info;
413 indio_dev->modes = INDIO_DIRECT_MODE;
415 = &ad5791_channels[spi_get_device_id(spi)->driver_data];
416 indio_dev->num_channels = 1;
417 indio_dev->name = spi_get_device_id(st->spi)->name;
418 ret = iio_device_register(indio_dev);
420 goto error_disable_reg_neg;
424 error_disable_reg_neg:
425 if (!IS_ERR(st->reg_vss))
426 regulator_disable(st->reg_vss);
428 if (!IS_ERR(st->reg_vss))
429 regulator_put(st->reg_vss);
431 if (!IS_ERR(st->reg_vdd))
432 regulator_disable(st->reg_vdd);
434 if (!IS_ERR(st->reg_vdd))
435 regulator_put(st->reg_vdd);
436 iio_device_free(indio_dev);
442 static int __devexit ad5791_remove(struct spi_device *spi)
444 struct iio_dev *indio_dev = spi_get_drvdata(spi);
445 struct ad5791_state *st = iio_priv(indio_dev);
447 iio_device_unregister(indio_dev);
448 if (!IS_ERR(st->reg_vdd)) {
449 regulator_disable(st->reg_vdd);
450 regulator_put(st->reg_vdd);
453 if (!IS_ERR(st->reg_vss)) {
454 regulator_disable(st->reg_vss);
455 regulator_put(st->reg_vss);
457 iio_device_free(indio_dev);
462 static const struct spi_device_id ad5791_id[] = {
463 {"ad5760", ID_AD5760},
464 {"ad5780", ID_AD5780},
465 {"ad5781", ID_AD5781},
466 {"ad5790", ID_AD5791},
467 {"ad5791", ID_AD5791},
470 MODULE_DEVICE_TABLE(spi, ad5791_id);
472 static struct spi_driver ad5791_driver = {
475 .owner = THIS_MODULE,
477 .probe = ad5791_probe,
478 .remove = __devexit_p(ad5791_remove),
479 .id_table = ad5791_id,
481 module_spi_driver(ad5791_driver);
483 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
484 MODULE_DESCRIPTION("Analog Devices AD5760/AD5780/AD5781/AD5790/AD5791 DAC");
485 MODULE_LICENSE("GPL v2");