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9#include <linux/interrupt.h>
10#include <linux/fs.h>
11#include <linux/device.h>
12#include <linux/kernel.h>
13#include <linux/spi/spi.h>
14#include <linux/slab.h>
15#include <linux/sysfs.h>
16#include <linux/regulator/consumer.h>
17#include <linux/module.h>
18#include <linux/bitops.h>
19
20#include <linux/iio/iio.h>
21#include <linux/iio/sysfs.h>
22#include <linux/iio/events.h>
23#include <linux/iio/dac/ad5504.h>
24
25#define AD5504_RES_MASK GENMASK(11, 0)
26#define AD5504_CMD_READ BIT(15)
27#define AD5504_CMD_WRITE 0
28#define AD5504_ADDR(addr) ((addr) << 12)
29
30
31#define AD5504_ADDR_NOOP 0
32#define AD5504_ADDR_DAC(x) ((x) + 1)
33#define AD5504_ADDR_ALL_DAC 5
34#define AD5504_ADDR_CTRL 7
35
36
37#define AD5504_DAC_PWR(ch) ((ch) << 2)
38#define AD5504_DAC_PWRDWN_MODE(mode) ((mode) << 6)
39#define AD5504_DAC_PWRDN_20K 0
40#define AD5504_DAC_PWRDN_3STATE 1
41
42
43
44
45
46
47
48
49
50
51struct ad5504_state {
52 struct spi_device *spi;
53 struct regulator *reg;
54 unsigned short vref_mv;
55 unsigned pwr_down_mask;
56 unsigned pwr_down_mode;
57
58 __be16 data[2] ____cacheline_aligned;
59};
60
61
62
63
64
65enum ad5504_supported_device_ids {
66 ID_AD5504,
67 ID_AD5501,
68};
69
70static int ad5504_spi_write(struct ad5504_state *st, u8 addr, u16 val)
71{
72 st->data[0] = cpu_to_be16(AD5504_CMD_WRITE | AD5504_ADDR(addr) |
73 (val & AD5504_RES_MASK));
74
75 return spi_write(st->spi, &st->data[0], 2);
76}
77
78static int ad5504_spi_read(struct ad5504_state *st, u8 addr)
79{
80 int ret;
81 struct spi_transfer t = {
82 .tx_buf = &st->data[0],
83 .rx_buf = &st->data[1],
84 .len = 2,
85 };
86
87 st->data[0] = cpu_to_be16(AD5504_CMD_READ | AD5504_ADDR(addr));
88 ret = spi_sync_transfer(st->spi, &t, 1);
89 if (ret < 0)
90 return ret;
91
92 return be16_to_cpu(st->data[1]) & AD5504_RES_MASK;
93}
94
95static int ad5504_read_raw(struct iio_dev *indio_dev,
96 struct iio_chan_spec const *chan,
97 int *val,
98 int *val2,
99 long m)
100{
101 struct ad5504_state *st = iio_priv(indio_dev);
102 int ret;
103
104 switch (m) {
105 case IIO_CHAN_INFO_RAW:
106 ret = ad5504_spi_read(st, chan->address);
107 if (ret < 0)
108 return ret;
109
110 *val = ret;
111
112 return IIO_VAL_INT;
113 case IIO_CHAN_INFO_SCALE:
114 *val = st->vref_mv;
115 *val2 = chan->scan_type.realbits;
116 return IIO_VAL_FRACTIONAL_LOG2;
117 }
118 return -EINVAL;
119}
120
121static int ad5504_write_raw(struct iio_dev *indio_dev,
122 struct iio_chan_spec const *chan,
123 int val,
124 int val2,
125 long mask)
126{
127 struct ad5504_state *st = iio_priv(indio_dev);
128
129 switch (mask) {
130 case IIO_CHAN_INFO_RAW:
131 if (val >= (1 << chan->scan_type.realbits) || val < 0)
132 return -EINVAL;
133
134 return ad5504_spi_write(st, chan->address, val);
135 default:
136 return -EINVAL;
137 }
138}
139
140static const char * const ad5504_powerdown_modes[] = {
141 "20kohm_to_gnd",
142 "three_state",
143};
144
145static int ad5504_get_powerdown_mode(struct iio_dev *indio_dev,
146 const struct iio_chan_spec *chan)
147{
148 struct ad5504_state *st = iio_priv(indio_dev);
149
150 return st->pwr_down_mode;
151}
152
153static int ad5504_set_powerdown_mode(struct iio_dev *indio_dev,
154 const struct iio_chan_spec *chan, unsigned int mode)
155{
156 struct ad5504_state *st = iio_priv(indio_dev);
157
158 st->pwr_down_mode = mode;
159
160 return 0;
161}
162
163static const struct iio_enum ad5504_powerdown_mode_enum = {
164 .items = ad5504_powerdown_modes,
165 .num_items = ARRAY_SIZE(ad5504_powerdown_modes),
166 .get = ad5504_get_powerdown_mode,
167 .set = ad5504_set_powerdown_mode,
168};
169
170static ssize_t ad5504_read_dac_powerdown(struct iio_dev *indio_dev,
171 uintptr_t private, const struct iio_chan_spec *chan, char *buf)
172{
173 struct ad5504_state *st = iio_priv(indio_dev);
174
175 return sprintf(buf, "%d\n",
176 !(st->pwr_down_mask & (1 << chan->channel)));
177}
178
179static ssize_t ad5504_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 pwr_down;
184 int ret;
185 struct ad5504_state *st = iio_priv(indio_dev);
186
187 ret = strtobool(buf, &pwr_down);
188 if (ret)
189 return ret;
190
191 if (pwr_down)
192 st->pwr_down_mask |= (1 << chan->channel);
193 else
194 st->pwr_down_mask &= ~(1 << chan->channel);
195
196 ret = ad5504_spi_write(st, AD5504_ADDR_CTRL,
197 AD5504_DAC_PWRDWN_MODE(st->pwr_down_mode) |
198 AD5504_DAC_PWR(st->pwr_down_mask));
199
200
201 ad5504_spi_write(st, AD5504_ADDR_NOOP, 0);
202
203 return ret ? ret : len;
204}
205
206static IIO_CONST_ATTR(temp0_thresh_rising_value, "110000");
207static IIO_CONST_ATTR(temp0_thresh_rising_en, "1");
208
209static struct attribute *ad5504_ev_attributes[] = {
210 &iio_const_attr_temp0_thresh_rising_value.dev_attr.attr,
211 &iio_const_attr_temp0_thresh_rising_en.dev_attr.attr,
212 NULL,
213};
214
215static struct attribute_group ad5504_ev_attribute_group = {
216 .attrs = ad5504_ev_attributes,
217};
218
219static irqreturn_t ad5504_event_handler(int irq, void *private)
220{
221 iio_push_event(private,
222 IIO_UNMOD_EVENT_CODE(IIO_TEMP,
223 0,
224 IIO_EV_TYPE_THRESH,
225 IIO_EV_DIR_RISING),
226 iio_get_time_ns((struct iio_dev *)private));
227
228 return IRQ_HANDLED;
229}
230
231static const struct iio_info ad5504_info = {
232 .write_raw = ad5504_write_raw,
233 .read_raw = ad5504_read_raw,
234 .event_attrs = &ad5504_ev_attribute_group,
235 .driver_module = THIS_MODULE,
236};
237
238static const struct iio_chan_spec_ext_info ad5504_ext_info[] = {
239 {
240 .name = "powerdown",
241 .read = ad5504_read_dac_powerdown,
242 .write = ad5504_write_dac_powerdown,
243 .shared = IIO_SEPARATE,
244 },
245 IIO_ENUM("powerdown_mode", IIO_SHARED_BY_TYPE,
246 &ad5504_powerdown_mode_enum),
247 IIO_ENUM_AVAILABLE("powerdown_mode", &ad5504_powerdown_mode_enum),
248 { },
249};
250
251#define AD5504_CHANNEL(_chan) { \
252 .type = IIO_VOLTAGE, \
253 .indexed = 1, \
254 .output = 1, \
255 .channel = (_chan), \
256 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
257 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
258 .address = AD5504_ADDR_DAC(_chan), \
259 .scan_type = { \
260 .sign = 'u', \
261 .realbits = 12, \
262 .storagebits = 16, \
263 }, \
264 .ext_info = ad5504_ext_info, \
265}
266
267static const struct iio_chan_spec ad5504_channels[] = {
268 AD5504_CHANNEL(0),
269 AD5504_CHANNEL(1),
270 AD5504_CHANNEL(2),
271 AD5504_CHANNEL(3),
272};
273
274static int ad5504_probe(struct spi_device *spi)
275{
276 struct ad5504_platform_data *pdata = spi->dev.platform_data;
277 struct iio_dev *indio_dev;
278 struct ad5504_state *st;
279 struct regulator *reg;
280 int ret, voltage_uv = 0;
281
282 indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
283 if (!indio_dev)
284 return -ENOMEM;
285 reg = devm_regulator_get(&spi->dev, "vcc");
286 if (!IS_ERR(reg)) {
287 ret = regulator_enable(reg);
288 if (ret)
289 return ret;
290
291 ret = regulator_get_voltage(reg);
292 if (ret < 0)
293 goto error_disable_reg;
294
295 voltage_uv = ret;
296 }
297
298 spi_set_drvdata(spi, indio_dev);
299 st = iio_priv(indio_dev);
300 if (voltage_uv)
301 st->vref_mv = voltage_uv / 1000;
302 else if (pdata)
303 st->vref_mv = pdata->vref_mv;
304 else
305 dev_warn(&spi->dev, "reference voltage unspecified\n");
306
307 st->reg = reg;
308 st->spi = spi;
309 indio_dev->dev.parent = &spi->dev;
310 indio_dev->name = spi_get_device_id(st->spi)->name;
311 indio_dev->info = &ad5504_info;
312 if (spi_get_device_id(st->spi)->driver_data == ID_AD5501)
313 indio_dev->num_channels = 1;
314 else
315 indio_dev->num_channels = 4;
316 indio_dev->channels = ad5504_channels;
317 indio_dev->modes = INDIO_DIRECT_MODE;
318
319 if (spi->irq) {
320 ret = devm_request_threaded_irq(&spi->dev, spi->irq,
321 NULL,
322 &ad5504_event_handler,
323 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
324 spi_get_device_id(st->spi)->name,
325 indio_dev);
326 if (ret)
327 goto error_disable_reg;
328 }
329
330 ret = iio_device_register(indio_dev);
331 if (ret)
332 goto error_disable_reg;
333
334 return 0;
335
336error_disable_reg:
337 if (!IS_ERR(reg))
338 regulator_disable(reg);
339
340 return ret;
341}
342
343static int ad5504_remove(struct spi_device *spi)
344{
345 struct iio_dev *indio_dev = spi_get_drvdata(spi);
346 struct ad5504_state *st = iio_priv(indio_dev);
347
348 iio_device_unregister(indio_dev);
349
350 if (!IS_ERR(st->reg))
351 regulator_disable(st->reg);
352
353 return 0;
354}
355
356static const struct spi_device_id ad5504_id[] = {
357 {"ad5504", ID_AD5504},
358 {"ad5501", ID_AD5501},
359 {}
360};
361MODULE_DEVICE_TABLE(spi, ad5504_id);
362
363static struct spi_driver ad5504_driver = {
364 .driver = {
365 .name = "ad5504",
366 },
367 .probe = ad5504_probe,
368 .remove = ad5504_remove,
369 .id_table = ad5504_id,
370};
371module_spi_driver(ad5504_driver);
372
373MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
374MODULE_DESCRIPTION("Analog Devices AD5501/AD5501 DAC");
375MODULE_LICENSE("GPL v2");
376
