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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
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 AD5505_BITS 12
25#define AD5504_RES_MASK ((1 << (AD5505_BITS)) - 1)
26
27#define AD5504_CMD_READ (1 << 15)
28#define AD5504_CMD_WRITE (0 << 15)
29#define AD5504_ADDR(addr) ((addr) << 12)
30
31
32#define AD5504_ADDR_NOOP 0
33#define AD5504_ADDR_DAC(x) ((x) + 1)
34#define AD5504_ADDR_ALL_DAC 5
35#define AD5504_ADDR_CTRL 7
36
37
38#define AD5504_DAC_PWR(ch) ((ch) << 2)
39#define AD5504_DAC_PWRDWN_MODE(mode) ((mode) << 6)
40#define AD5504_DAC_PWRDN_20K 0
41#define AD5504_DAC_PWRDN_3STATE 1
42
43
44
45
46
47
48
49
50
51
52struct ad5504_state {
53 struct spi_device *spi;
54 struct regulator *reg;
55 unsigned short vref_mv;
56 unsigned pwr_down_mask;
57 unsigned pwr_down_mode;
58};
59
60
61
62
63
64enum ad5504_supported_device_ids {
65 ID_AD5504,
66 ID_AD5501,
67};
68
69static int ad5504_spi_write(struct spi_device *spi, u8 addr, u16 val)
70{
71 u16 tmp = cpu_to_be16(AD5504_CMD_WRITE |
72 AD5504_ADDR(addr) |
73 (val & AD5504_RES_MASK));
74
75 return spi_write(spi, (u8 *)&tmp, 2);
76}
77
78static int ad5504_spi_read(struct spi_device *spi, u8 addr)
79{
80 u16 tmp = cpu_to_be16(AD5504_CMD_READ | AD5504_ADDR(addr));
81 u16 val;
82 int ret;
83 struct spi_transfer t = {
84 .tx_buf = &tmp,
85 .rx_buf = &val,
86 .len = 2,
87 };
88 ret = spi_sync_transfer(spi, &t, 1);
89
90 if (ret < 0)
91 return ret;
92
93 return be16_to_cpu(val) & AD5504_RES_MASK;
94}
95
96static int ad5504_read_raw(struct iio_dev *indio_dev,
97 struct iio_chan_spec const *chan,
98 int *val,
99 int *val2,
100 long m)
101{
102 struct ad5504_state *st = iio_priv(indio_dev);
103 unsigned long scale_uv;
104 int ret;
105
106 switch (m) {
107 case IIO_CHAN_INFO_RAW:
108 ret = ad5504_spi_read(st->spi, chan->address);
109 if (ret < 0)
110 return ret;
111
112 *val = ret;
113
114 return IIO_VAL_INT;
115 case IIO_CHAN_INFO_SCALE:
116 scale_uv = (st->vref_mv * 1000) >> chan->scan_type.realbits;
117 *val = scale_uv / 1000;
118 *val2 = (scale_uv % 1000) * 1000;
119 return IIO_VAL_INT_PLUS_MICRO;
120
121 }
122 return -EINVAL;
123}
124
125static int ad5504_write_raw(struct iio_dev *indio_dev,
126 struct iio_chan_spec const *chan,
127 int val,
128 int val2,
129 long mask)
130{
131 struct ad5504_state *st = iio_priv(indio_dev);
132 int ret;
133
134 switch (mask) {
135 case IIO_CHAN_INFO_RAW:
136 if (val >= (1 << chan->scan_type.realbits) || val < 0)
137 return -EINVAL;
138
139 return ad5504_spi_write(st->spi, chan->address, val);
140 default:
141 ret = -EINVAL;
142 }
143
144 return -EINVAL;
145}
146
147static const char * const ad5504_powerdown_modes[] = {
148 "20kohm_to_gnd",
149 "three_state",
150};
151
152static int ad5504_get_powerdown_mode(struct iio_dev *indio_dev,
153 const struct iio_chan_spec *chan)
154{
155 struct ad5504_state *st = iio_priv(indio_dev);
156
157 return st->pwr_down_mode;
158}
159
160static int ad5504_set_powerdown_mode(struct iio_dev *indio_dev,
161 const struct iio_chan_spec *chan, unsigned int mode)
162{
163 struct ad5504_state *st = iio_priv(indio_dev);
164
165 st->pwr_down_mode = mode;
166
167 return 0;
168}
169
170static const struct iio_enum ad5504_powerdown_mode_enum = {
171 .items = ad5504_powerdown_modes,
172 .num_items = ARRAY_SIZE(ad5504_powerdown_modes),
173 .get = ad5504_get_powerdown_mode,
174 .set = ad5504_set_powerdown_mode,
175};
176
177static ssize_t ad5504_read_dac_powerdown(struct iio_dev *indio_dev,
178 uintptr_t private, const struct iio_chan_spec *chan, char *buf)
179{
180 struct ad5504_state *st = iio_priv(indio_dev);
181
182 return sprintf(buf, "%d\n",
183 !(st->pwr_down_mask & (1 << chan->channel)));
184}
185
186static ssize_t ad5504_write_dac_powerdown(struct iio_dev *indio_dev,
187 uintptr_t private, const struct iio_chan_spec *chan, const char *buf,
188 size_t len)
189{
190 bool pwr_down;
191 int ret;
192 struct ad5504_state *st = iio_priv(indio_dev);
193
194 ret = strtobool(buf, &pwr_down);
195 if (ret)
196 return ret;
197
198 if (pwr_down)
199 st->pwr_down_mask |= (1 << chan->channel);
200 else
201 st->pwr_down_mask &= ~(1 << chan->channel);
202
203 ret = ad5504_spi_write(st->spi, AD5504_ADDR_CTRL,
204 AD5504_DAC_PWRDWN_MODE(st->pwr_down_mode) |
205 AD5504_DAC_PWR(st->pwr_down_mask));
206
207
208 ad5504_spi_write(st->spi, AD5504_ADDR_NOOP, 0);
209
210 return ret ? ret : len;
211}
212
213static IIO_CONST_ATTR(temp0_thresh_rising_value, "110000");
214static IIO_CONST_ATTR(temp0_thresh_rising_en, "1");
215
216static struct attribute *ad5504_ev_attributes[] = {
217 &iio_const_attr_temp0_thresh_rising_value.dev_attr.attr,
218 &iio_const_attr_temp0_thresh_rising_en.dev_attr.attr,
219 NULL,
220};
221
222static struct attribute_group ad5504_ev_attribute_group = {
223 .attrs = ad5504_ev_attributes,
224 .name = "events",
225};
226
227static irqreturn_t ad5504_event_handler(int irq, void *private)
228{
229 iio_push_event(private,
230 IIO_UNMOD_EVENT_CODE(IIO_TEMP,
231 0,
232 IIO_EV_TYPE_THRESH,
233 IIO_EV_DIR_RISING),
234 iio_get_time_ns());
235
236 return IRQ_HANDLED;
237}
238
239static const struct iio_info ad5504_info = {
240 .write_raw = ad5504_write_raw,
241 .read_raw = ad5504_read_raw,
242 .event_attrs = &ad5504_ev_attribute_group,
243 .driver_module = THIS_MODULE,
244};
245
246static const struct iio_chan_spec_ext_info ad5504_ext_info[] = {
247 {
248 .name = "powerdown",
249 .read = ad5504_read_dac_powerdown,
250 .write = ad5504_write_dac_powerdown,
251 },
252 IIO_ENUM("powerdown_mode", true, &ad5504_powerdown_mode_enum),
253 IIO_ENUM_AVAILABLE("powerdown_mode", &ad5504_powerdown_mode_enum),
254 { },
255};
256
257#define AD5504_CHANNEL(_chan) { \
258 .type = IIO_VOLTAGE, \
259 .indexed = 1, \
260 .output = 1, \
261 .channel = (_chan), \
262 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
263 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
264 .address = AD5504_ADDR_DAC(_chan), \
265 .scan_type = IIO_ST('u', 12, 16, 0), \
266 .ext_info = ad5504_ext_info, \
267}
268
269static const struct iio_chan_spec ad5504_channels[] = {
270 AD5504_CHANNEL(0),
271 AD5504_CHANNEL(1),
272 AD5504_CHANNEL(2),
273 AD5504_CHANNEL(3),
274};
275
276static int ad5504_probe(struct spi_device *spi)
277{
278 struct ad5504_platform_data *pdata = spi->dev.platform_data;
279 struct iio_dev *indio_dev;
280 struct ad5504_state *st;
281 struct regulator *reg;
282 int ret, voltage_uv = 0;
283
284 indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
285 if (!indio_dev)
286 return -ENOMEM;
287 reg = devm_regulator_get(&spi->dev, "vcc");
288 if (!IS_ERR(reg)) {
289 ret = regulator_enable(reg);
290 if (ret)
291 return ret;
292
293 ret = regulator_get_voltage(reg);
294 if (ret < 0)
295 goto error_disable_reg;
296
297 voltage_uv = ret;
298 }
299
300 spi_set_drvdata(spi, indio_dev);
301 st = iio_priv(indio_dev);
302 if (voltage_uv)
303 st->vref_mv = voltage_uv / 1000;
304 else if (pdata)
305 st->vref_mv = pdata->vref_mv;
306 else
307 dev_warn(&spi->dev, "reference voltage unspecified\n");
308
309 st->reg = reg;
310 st->spi = spi;
311 indio_dev->dev.parent = &spi->dev;
312 indio_dev->name = spi_get_device_id(st->spi)->name;
313 indio_dev->info = &ad5504_info;
314 if (spi_get_device_id(st->spi)->driver_data == ID_AD5501)
315 indio_dev->num_channels = 1;
316 else
317 indio_dev->num_channels = 4;
318 indio_dev->channels = ad5504_channels;
319 indio_dev->modes = INDIO_DIRECT_MODE;
320
321 if (spi->irq) {
322 ret = devm_request_threaded_irq(&spi->dev, spi->irq,
323 NULL,
324 &ad5504_event_handler,
325 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
326 spi_get_device_id(st->spi)->name,
327 indio_dev);
328 if (ret)
329 goto error_disable_reg;
330 }
331
332 ret = iio_device_register(indio_dev);
333 if (ret)
334 goto error_disable_reg;
335
336 return 0;
337
338error_disable_reg:
339 if (!IS_ERR(reg))
340 regulator_disable(reg);
341
342 return ret;
343}
344
345static int ad5504_remove(struct spi_device *spi)
346{
347 struct iio_dev *indio_dev = spi_get_drvdata(spi);
348 struct ad5504_state *st = iio_priv(indio_dev);
349
350 iio_device_unregister(indio_dev);
351
352 if (!IS_ERR(st->reg))
353 regulator_disable(st->reg);
354
355 return 0;
356}
357
358static const struct spi_device_id ad5504_id[] = {
359 {"ad5504", ID_AD5504},
360 {"ad5501", ID_AD5501},
361 {}
362};
363MODULE_DEVICE_TABLE(spi, ad5504_id);
364
365static struct spi_driver ad5504_driver = {
366 .driver = {
367 .name = "ad5504",
368 .owner = THIS_MODULE,
369 },
370 .probe = ad5504_probe,
371 .remove = ad5504_remove,
372 .id_table = ad5504_id,
373};
374module_spi_driver(ad5504_driver);
375
376MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
377MODULE_DESCRIPTION("Analog Devices AD5501/AD5501 DAC");
378MODULE_LICENSE("GPL v2");
379
