2 * AD5415, AD5426, AD5429, AD5432, AD5439, AD5443, AD5449 Digital to Analog
5 * Copyright 2012 Analog Devices Inc.
6 * Author: Lars-Peter Clausen <lars@metafoo.de>
8 * Licensed under the GPL-2.
11 #include <linux/device.h>
12 #include <linux/err.h>
13 #include <linux/module.h>
14 #include <linux/kernel.h>
15 #include <linux/spi/spi.h>
16 #include <linux/slab.h>
17 #include <linux/sysfs.h>
18 #include <linux/regulator/consumer.h>
19 #include <asm/unaligned.h>
21 #include <linux/iio/iio.h>
22 #include <linux/iio/sysfs.h>
24 #include <linux/platform_data/ad5449.h>
26 #define AD5449_MAX_CHANNELS 2
27 #define AD5449_MAX_VREFS 2
29 #define AD5449_CMD_NOOP 0x0
30 #define AD5449_CMD_LOAD_AND_UPDATE(x) (0x1 + (x) * 3)
31 #define AD5449_CMD_READ(x) (0x2 + (x) * 3)
32 #define AD5449_CMD_LOAD(x) (0x3 + (x) * 3)
33 #define AD5449_CMD_CTRL 13
35 #define AD5449_CTRL_SDO_OFFSET 10
36 #define AD5449_CTRL_DAISY_CHAIN BIT(9)
37 #define AD5449_CTRL_HCLR_TO_MIDSCALE BIT(8)
38 #define AD5449_CTRL_SAMPLE_RISING BIT(7)
41 * struct ad5449_chip_info - chip specific information
42 * @channels: Channel specification
43 * @num_channels: Number of channels
44 * @has_ctrl: Chip has a control register
46 struct ad5449_chip_info {
47 const struct iio_chan_spec *channels;
48 unsigned int num_channels;
53 * struct ad5449 - driver instance specific data
54 * @spi: the SPI device for this driver instance
55 * @chip_info: chip model specific constants, available modes etc
56 * @vref_reg: vref supply regulators
57 * @has_sdo: whether the SDO line is connected
58 * @dac_cache: Cache for the DAC values
59 * @data: spi transfer buffers
62 struct spi_device *spi;
63 const struct ad5449_chip_info *chip_info;
64 struct regulator_bulk_data vref_reg[AD5449_MAX_VREFS];
67 uint16_t dac_cache[AD5449_MAX_CHANNELS];
70 * DMA (thus cache coherency maintenance) requires the
71 * transfer buffers to live in their own cache lines.
73 __be16 data[2] ____cacheline_aligned;
85 static int ad5449_write(struct iio_dev *indio_dev, unsigned int addr,
88 struct ad5449 *st = iio_priv(indio_dev);
91 mutex_lock(&indio_dev->mlock);
92 st->data[0] = cpu_to_be16((addr << 12) | val);
93 ret = spi_write(st->spi, st->data, 2);
94 mutex_unlock(&indio_dev->mlock);
99 static int ad5449_read(struct iio_dev *indio_dev, unsigned int addr,
102 struct ad5449 *st = iio_priv(indio_dev);
104 struct spi_message msg;
105 struct spi_transfer t[] = {
107 .tx_buf = &st->data[0],
111 .tx_buf = &st->data[1],
112 .rx_buf = &st->data[1],
117 spi_message_init(&msg);
118 spi_message_add_tail(&t[0], &msg);
119 spi_message_add_tail(&t[1], &msg);
121 mutex_lock(&indio_dev->mlock);
122 st->data[0] = cpu_to_be16(addr << 12);
123 st->data[1] = cpu_to_be16(AD5449_CMD_NOOP);
125 ret = spi_sync(st->spi, &msg);
129 *val = be16_to_cpu(st->data[1]);
132 mutex_unlock(&indio_dev->mlock);
136 static int ad5449_read_raw(struct iio_dev *indio_dev,
137 struct iio_chan_spec const *chan, int *val, int *val2, long info)
139 struct ad5449 *st = iio_priv(indio_dev);
140 struct regulator_bulk_data *reg;
145 case IIO_CHAN_INFO_RAW:
147 ret = ad5449_read(indio_dev,
148 AD5449_CMD_READ(chan->address), val);
153 *val = st->dac_cache[chan->address];
157 case IIO_CHAN_INFO_SCALE:
158 reg = &st->vref_reg[chan->channel];
159 scale_uv = regulator_get_voltage(reg->consumer);
163 *val = scale_uv / 1000;
164 *val2 = chan->scan_type.realbits;
166 return IIO_VAL_FRACTIONAL_LOG2;
174 static int ad5449_write_raw(struct iio_dev *indio_dev,
175 struct iio_chan_spec const *chan, int val, int val2, long info)
177 struct ad5449 *st = iio_priv(indio_dev);
181 case IIO_CHAN_INFO_RAW:
182 if (val < 0 || val >= (1 << chan->scan_type.realbits))
185 ret = ad5449_write(indio_dev,
186 AD5449_CMD_LOAD_AND_UPDATE(chan->address),
187 val << chan->scan_type.shift);
189 st->dac_cache[chan->address] = val;
198 static const struct iio_info ad5449_info = {
199 .read_raw = ad5449_read_raw,
200 .write_raw = ad5449_write_raw,
201 .driver_module = THIS_MODULE,
204 #define AD5449_CHANNEL(chan, bits) { \
205 .type = IIO_VOLTAGE, \
209 .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT | \
210 IIO_CHAN_INFO_SCALE_SEPARATE_BIT, \
212 .scan_type = IIO_ST('u', (bits), 16, 12 - (bits)), \
215 #define DECLARE_AD5449_CHANNELS(name, bits) \
216 const struct iio_chan_spec name[] = { \
217 AD5449_CHANNEL(0, bits), \
218 AD5449_CHANNEL(1, bits), \
221 static DECLARE_AD5449_CHANNELS(ad5429_channels, 8);
222 static DECLARE_AD5449_CHANNELS(ad5439_channels, 10);
223 static DECLARE_AD5449_CHANNELS(ad5449_channels, 12);
225 static const struct ad5449_chip_info ad5449_chip_info[] = {
227 .channels = ad5429_channels,
232 .channels = ad5429_channels,
237 .channels = ad5439_channels,
242 .channels = ad5439_channels,
247 .channels = ad5449_channels,
252 .channels = ad5449_channels,
258 static const char *ad5449_vref_name(struct ad5449 *st, int n)
260 if (st->chip_info->num_channels == 1)
269 static int __devinit ad5449_spi_probe(struct spi_device *spi)
271 struct ad5449_platform_data *pdata = spi->dev.platform_data;
272 const struct spi_device_id *id = spi_get_device_id(spi);
273 struct iio_dev *indio_dev;
278 indio_dev = iio_device_alloc(sizeof(*st));
279 if (indio_dev == NULL)
282 st = iio_priv(indio_dev);
283 spi_set_drvdata(spi, indio_dev);
285 st->chip_info = &ad5449_chip_info[id->driver_data];
288 for (i = 0; i < st->chip_info->num_channels; ++i)
289 st->vref_reg[i].supply = ad5449_vref_name(st, i);
291 ret = regulator_bulk_get(&spi->dev, st->chip_info->num_channels,
296 ret = regulator_bulk_enable(st->chip_info->num_channels, st->vref_reg);
300 indio_dev->dev.parent = &spi->dev;
301 indio_dev->name = id->name;
302 indio_dev->info = &ad5449_info;
303 indio_dev->modes = INDIO_DIRECT_MODE;
304 indio_dev->channels = st->chip_info->channels;
305 indio_dev->num_channels = st->chip_info->num_channels;
307 if (st->chip_info->has_ctrl) {
308 unsigned int ctrl = 0x00;
310 if (pdata->hardware_clear_to_midscale)
311 ctrl |= AD5449_CTRL_HCLR_TO_MIDSCALE;
312 ctrl |= pdata->sdo_mode << AD5449_CTRL_SDO_OFFSET;
313 st->has_sdo = pdata->sdo_mode != AD5449_SDO_DISABLED;
317 ad5449_write(indio_dev, AD5449_CMD_CTRL, ctrl);
320 ret = iio_device_register(indio_dev);
322 goto error_disable_reg;
327 regulator_bulk_disable(st->chip_info->num_channels, st->vref_reg);
329 regulator_bulk_free(st->chip_info->num_channels, st->vref_reg);
331 iio_device_free(indio_dev);
336 static int __devexit ad5449_spi_remove(struct spi_device *spi)
338 struct iio_dev *indio_dev = spi_get_drvdata(spi);
339 struct ad5449 *st = iio_priv(indio_dev);
341 iio_device_unregister(indio_dev);
343 regulator_bulk_disable(st->chip_info->num_channels, st->vref_reg);
344 regulator_bulk_free(st->chip_info->num_channels, st->vref_reg);
346 iio_device_free(indio_dev);
351 static const struct spi_device_id ad5449_spi_ids[] = {
352 { "ad5415", ID_AD5449 },
353 { "ad5426", ID_AD5426 },
354 { "ad5429", ID_AD5429 },
355 { "ad5432", ID_AD5432 },
356 { "ad5439", ID_AD5439 },
357 { "ad5443", ID_AD5443 },
358 { "ad5449", ID_AD5449 },
361 MODULE_DEVICE_TABLE(spi, ad5449_spi_ids);
363 static struct spi_driver ad5449_spi_driver = {
366 .owner = THIS_MODULE,
368 .probe = ad5449_spi_probe,
369 .remove = __devexit_p(ad5449_spi_remove),
370 .id_table = ad5449_spi_ids,
372 module_spi_driver(ad5449_spi_driver);
374 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
375 MODULE_DESCRIPTION("Analog Devices AD5449 and similar DACs");
376 MODULE_LICENSE("GPL v2");