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8#include <linux/interrupt.h>
9#include <linux/fs.h>
10#include <linux/device.h>
11#include <linux/kernel.h>
12#include <linux/spi/spi.h>
13#include <linux/slab.h>
14#include <linux/sysfs.h>
15#include <linux/regulator/consumer.h>
16#include <linux/module.h>
17#include <linux/bitops.h>
18
19#include <linux/iio/iio.h>
20#include <linux/iio/sysfs.h>
21#include <linux/iio/events.h>
22#include <linux/iio/dac/ad5504.h>
23
24#define AD5504_RES_MASK GENMASK(11, 0)
25#define AD5504_CMD_READ BIT(15)
26#define AD5504_CMD_WRITE 0
27#define AD5504_ADDR(addr) ((addr) << 12)
28
29
30#define AD5504_ADDR_NOOP 0
31#define AD5504_ADDR_DAC(x) ((x) + 1)
32#define AD5504_ADDR_ALL_DAC 5
33#define AD5504_ADDR_CTRL 7
34
35
36#define AD5504_DAC_PWR(ch) ((ch) << 2)
37#define AD5504_DAC_PWRDWN_MODE(mode) ((mode) << 6)
38#define AD5504_DAC_PWRDN_20K 0
39#define AD5504_DAC_PWRDN_3STATE 1
40
41
42
43
44
45
46
47
48
49
50struct ad5504_state {
51 struct spi_device *spi;
52 struct regulator *reg;
53 unsigned short vref_mv;
54 unsigned pwr_down_mask;
55 unsigned pwr_down_mode;
56
57 __be16 data[2] ____cacheline_aligned;
58};
59
60
61
62
63enum ad5504_supported_device_ids {
64 ID_AD5504,
65 ID_AD5501,
66};
67
68static int ad5504_spi_write(struct ad5504_state *st, u8 addr, u16 val)
69{
70 st->data[0] = cpu_to_be16(AD5504_CMD_WRITE | AD5504_ADDR(addr) |
71 (val & AD5504_RES_MASK));
72
73 return spi_write(st->spi, &st->data[0], 2);
74}
75
76static int ad5504_spi_read(struct ad5504_state *st, u8 addr)
77{
78 int ret;
79 struct spi_transfer t = {
80 .tx_buf = &st->data[0],
81 .rx_buf = &st->data[1],
82 .len = 2,
83 };
84
85 st->data[0] = cpu_to_be16(AD5504_CMD_READ | AD5504_ADDR(addr));
86 ret = spi_sync_transfer(st->spi, &t, 1);
87 if (ret < 0)
88 return ret;
89
90 return be16_to_cpu(st->data[1]) & AD5504_RES_MASK;
91}
92
93static int ad5504_read_raw(struct iio_dev *indio_dev,
94 struct iio_chan_spec const *chan,
95 int *val,
96 int *val2,
97 long m)
98{
99 struct ad5504_state *st = iio_priv(indio_dev);
100 int ret;
101
102 switch (m) {
103 case IIO_CHAN_INFO_RAW:
104 ret = ad5504_spi_read(st, chan->address);
105 if (ret < 0)
106 return ret;
107
108 *val = ret;
109
110 return IIO_VAL_INT;
111 case IIO_CHAN_INFO_SCALE:
112 *val = st->vref_mv;
113 *val2 = chan->scan_type.realbits;
114 return IIO_VAL_FRACTIONAL_LOG2;
115 }
116 return -EINVAL;
117}
118
119static int ad5504_write_raw(struct iio_dev *indio_dev,
120 struct iio_chan_spec const *chan,
121 int val,
122 int val2,
123 long mask)
124{
125 struct ad5504_state *st = iio_priv(indio_dev);
126
127 switch (mask) {
128 case IIO_CHAN_INFO_RAW:
129 if (val >= (1 << chan->scan_type.realbits) || val < 0)
130 return -EINVAL;
131
132 return ad5504_spi_write(st, chan->address, val);
133 default:
134 return -EINVAL;
135 }
136}
137
138static const char * const ad5504_powerdown_modes[] = {
139 "20kohm_to_gnd",
140 "three_state",
141};
142
143static int ad5504_get_powerdown_mode(struct iio_dev *indio_dev,
144 const struct iio_chan_spec *chan)
145{
146 struct ad5504_state *st = iio_priv(indio_dev);
147
148 return st->pwr_down_mode;
149}
150
151static int ad5504_set_powerdown_mode(struct iio_dev *indio_dev,
152 const struct iio_chan_spec *chan, unsigned int mode)
153{
154 struct ad5504_state *st = iio_priv(indio_dev);
155
156 st->pwr_down_mode = mode;
157
158 return 0;
159}
160
161static const struct iio_enum ad5504_powerdown_mode_enum = {
162 .items = ad5504_powerdown_modes,
163 .num_items = ARRAY_SIZE(ad5504_powerdown_modes),
164 .get = ad5504_get_powerdown_mode,
165 .set = ad5504_set_powerdown_mode,
166};
167
168static ssize_t ad5504_read_dac_powerdown(struct iio_dev *indio_dev,
169 uintptr_t private, const struct iio_chan_spec *chan, char *buf)
170{
171 struct ad5504_state *st = iio_priv(indio_dev);
172
173 return sysfs_emit(buf, "%d\n",
174 !(st->pwr_down_mask & (1 << chan->channel)));
175}
176
177static ssize_t ad5504_write_dac_powerdown(struct iio_dev *indio_dev,
178 uintptr_t private, const struct iio_chan_spec *chan, const char *buf,
179 size_t len)
180{
181 bool pwr_down;
182 int ret;
183 struct ad5504_state *st = iio_priv(indio_dev);
184
185 ret = strtobool(buf, &pwr_down);
186 if (ret)
187 return ret;
188
189 if (pwr_down)
190 st->pwr_down_mask &= ~(1 << chan->channel);
191 else
192 st->pwr_down_mask |= (1 << chan->channel);
193
194 ret = ad5504_spi_write(st, AD5504_ADDR_CTRL,
195 AD5504_DAC_PWRDWN_MODE(st->pwr_down_mode) |
196 AD5504_DAC_PWR(st->pwr_down_mask));
197
198
199 ad5504_spi_write(st, AD5504_ADDR_NOOP, 0);
200
201 return ret ? ret : len;
202}
203
204static IIO_CONST_ATTR(temp0_thresh_rising_value, "110000");
205static IIO_CONST_ATTR(temp0_thresh_rising_en, "1");
206
207static struct attribute *ad5504_ev_attributes[] = {
208 &iio_const_attr_temp0_thresh_rising_value.dev_attr.attr,
209 &iio_const_attr_temp0_thresh_rising_en.dev_attr.attr,
210 NULL,
211};
212
213static const struct attribute_group ad5504_ev_attribute_group = {
214 .attrs = ad5504_ev_attributes,
215};
216
217static irqreturn_t ad5504_event_handler(int irq, void *private)
218{
219 iio_push_event(private,
220 IIO_UNMOD_EVENT_CODE(IIO_TEMP,
221 0,
222 IIO_EV_TYPE_THRESH,
223 IIO_EV_DIR_RISING),
224 iio_get_time_ns(private));
225
226 return IRQ_HANDLED;
227}
228
229static const struct iio_info ad5504_info = {
230 .write_raw = ad5504_write_raw,
231 .read_raw = ad5504_read_raw,
232 .event_attrs = &ad5504_ev_attribute_group,
233};
234
235static const struct iio_chan_spec_ext_info ad5504_ext_info[] = {
236 {
237 .name = "powerdown",
238 .read = ad5504_read_dac_powerdown,
239 .write = ad5504_write_dac_powerdown,
240 .shared = IIO_SEPARATE,
241 },
242 IIO_ENUM("powerdown_mode", IIO_SHARED_BY_TYPE,
243 &ad5504_powerdown_mode_enum),
244 IIO_ENUM_AVAILABLE("powerdown_mode", &ad5504_powerdown_mode_enum),
245 { },
246};
247
248#define AD5504_CHANNEL(_chan) { \
249 .type = IIO_VOLTAGE, \
250 .indexed = 1, \
251 .output = 1, \
252 .channel = (_chan), \
253 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
254 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
255 .address = AD5504_ADDR_DAC(_chan), \
256 .scan_type = { \
257 .sign = 'u', \
258 .realbits = 12, \
259 .storagebits = 16, \
260 }, \
261 .ext_info = ad5504_ext_info, \
262}
263
264static const struct iio_chan_spec ad5504_channels[] = {
265 AD5504_CHANNEL(0),
266 AD5504_CHANNEL(1),
267 AD5504_CHANNEL(2),
268 AD5504_CHANNEL(3),
269};
270
271static int ad5504_probe(struct spi_device *spi)
272{
273 struct ad5504_platform_data *pdata = spi->dev.platform_data;
274 struct iio_dev *indio_dev;
275 struct ad5504_state *st;
276 struct regulator *reg;
277 int ret, voltage_uv = 0;
278
279 indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
280 if (!indio_dev)
281 return -ENOMEM;
282 reg = devm_regulator_get(&spi->dev, "vcc");
283 if (!IS_ERR(reg)) {
284 ret = regulator_enable(reg);
285 if (ret)
286 return ret;
287
288 ret = regulator_get_voltage(reg);
289 if (ret < 0)
290 goto error_disable_reg;
291
292 voltage_uv = ret;
293 }
294
295 spi_set_drvdata(spi, indio_dev);
296 st = iio_priv(indio_dev);
297 if (voltage_uv)
298 st->vref_mv = voltage_uv / 1000;
299 else if (pdata)
300 st->vref_mv = pdata->vref_mv;
301 else
302 dev_warn(&spi->dev, "reference voltage unspecified\n");
303
304 st->reg = reg;
305 st->spi = spi;
306 indio_dev->name = spi_get_device_id(st->spi)->name;
307 indio_dev->info = &ad5504_info;
308 if (spi_get_device_id(st->spi)->driver_data == ID_AD5501)
309 indio_dev->num_channels = 1;
310 else
311 indio_dev->num_channels = 4;
312 indio_dev->channels = ad5504_channels;
313 indio_dev->modes = INDIO_DIRECT_MODE;
314
315 if (spi->irq) {
316 ret = devm_request_threaded_irq(&spi->dev, spi->irq,
317 NULL,
318 &ad5504_event_handler,
319 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
320 spi_get_device_id(st->spi)->name,
321 indio_dev);
322 if (ret)
323 goto error_disable_reg;
324 }
325
326 ret = iio_device_register(indio_dev);
327 if (ret)
328 goto error_disable_reg;
329
330 return 0;
331
332error_disable_reg:
333 if (!IS_ERR(reg))
334 regulator_disable(reg);
335
336 return ret;
337}
338
339static int ad5504_remove(struct spi_device *spi)
340{
341 struct iio_dev *indio_dev = spi_get_drvdata(spi);
342 struct ad5504_state *st = iio_priv(indio_dev);
343
344 iio_device_unregister(indio_dev);
345
346 if (!IS_ERR(st->reg))
347 regulator_disable(st->reg);
348
349 return 0;
350}
351
352static const struct spi_device_id ad5504_id[] = {
353 {"ad5504", ID_AD5504},
354 {"ad5501", ID_AD5501},
355 {}
356};
357MODULE_DEVICE_TABLE(spi, ad5504_id);
358
359static struct spi_driver ad5504_driver = {
360 .driver = {
361 .name = "ad5504",
362 },
363 .probe = ad5504_probe,
364 .remove = ad5504_remove,
365 .id_table = ad5504_id,
366};
367module_spi_driver(ad5504_driver);
368
369MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
370MODULE_DESCRIPTION("Analog Devices AD5501/AD5501 DAC");
371MODULE_LICENSE("GPL v2");
372
