1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * AD5624R, AD5644R, AD5664R Digital to analog convertors spi driver
4 *
5 * Copyright 2010-2011 Analog Devices Inc.
6 */
7
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
18 #include <linux/iio/iio.h>
19 #include <linux/iio/sysfs.h>
20
21 #include <asm/unaligned.h>
22
23 #include "ad5624r.h"
24
ad5624r_spi_write(struct spi_device * spi,u8 cmd,u8 addr,u16 val,u8 shift)25 static int ad5624r_spi_write(struct spi_device *spi,
26 u8 cmd, u8 addr, u16 val, u8 shift)
27 {
28 u32 data;
29 u8 msg[3];
30
31 /*
32 * The input shift register is 24 bits wide. The first two bits are
33 * don't care bits. The next three are the command bits, C2 to C0,
34 * followed by the 3-bit DAC address, A2 to A0, and then the
35 * 16-, 14-, 12-bit data-word. The data-word comprises the 16-,
36 * 14-, 12-bit input code followed by 0, 2, or 4 don't care bits,
37 * for the AD5664R, AD5644R, and AD5624R, respectively.
38 */
39 data = (0 << 22) | (cmd << 19) | (addr << 16) | (val << shift);
40 put_unaligned_be24(data, &msg[0]);
41
42 return spi_write(spi, msg, sizeof(msg));
43 }
44
ad5624r_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long m)45 static int ad5624r_read_raw(struct iio_dev *indio_dev,
46 struct iio_chan_spec const *chan,
47 int *val,
48 int *val2,
49 long m)
50 {
51 struct ad5624r_state *st = iio_priv(indio_dev);
52
53 switch (m) {
54 case IIO_CHAN_INFO_SCALE:
55 *val = st->vref_mv;
56 *val2 = chan->scan_type.realbits;
57 return IIO_VAL_FRACTIONAL_LOG2;
58 }
59 return -EINVAL;
60 }
61
ad5624r_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)62 static int ad5624r_write_raw(struct iio_dev *indio_dev,
63 struct iio_chan_spec const *chan,
64 int val,
65 int val2,
66 long mask)
67 {
68 struct ad5624r_state *st = iio_priv(indio_dev);
69
70 switch (mask) {
71 case IIO_CHAN_INFO_RAW:
72 if (val >= (1 << chan->scan_type.realbits) || val < 0)
73 return -EINVAL;
74
75 return ad5624r_spi_write(st->us,
76 AD5624R_CMD_WRITE_INPUT_N_UPDATE_N,
77 chan->address, val,
78 chan->scan_type.shift);
79 default:
80 return -EINVAL;
81 }
82 }
83
84 static const char * const ad5624r_powerdown_modes[] = {
85 "1kohm_to_gnd",
86 "100kohm_to_gnd",
87 "three_state"
88 };
89
ad5624r_get_powerdown_mode(struct iio_dev * indio_dev,const struct iio_chan_spec * chan)90 static int ad5624r_get_powerdown_mode(struct iio_dev *indio_dev,
91 const struct iio_chan_spec *chan)
92 {
93 struct ad5624r_state *st = iio_priv(indio_dev);
94
95 return st->pwr_down_mode;
96 }
97
ad5624r_set_powerdown_mode(struct iio_dev * indio_dev,const struct iio_chan_spec * chan,unsigned int mode)98 static int ad5624r_set_powerdown_mode(struct iio_dev *indio_dev,
99 const struct iio_chan_spec *chan, unsigned int mode)
100 {
101 struct ad5624r_state *st = iio_priv(indio_dev);
102
103 st->pwr_down_mode = mode;
104
105 return 0;
106 }
107
108 static const struct iio_enum ad5624r_powerdown_mode_enum = {
109 .items = ad5624r_powerdown_modes,
110 .num_items = ARRAY_SIZE(ad5624r_powerdown_modes),
111 .get = ad5624r_get_powerdown_mode,
112 .set = ad5624r_set_powerdown_mode,
113 };
114
ad5624r_read_dac_powerdown(struct iio_dev * indio_dev,uintptr_t private,const struct iio_chan_spec * chan,char * buf)115 static ssize_t ad5624r_read_dac_powerdown(struct iio_dev *indio_dev,
116 uintptr_t private, const struct iio_chan_spec *chan, char *buf)
117 {
118 struct ad5624r_state *st = iio_priv(indio_dev);
119
120 return sysfs_emit(buf, "%d\n",
121 !!(st->pwr_down_mask & (1 << chan->channel)));
122 }
123
ad5624r_write_dac_powerdown(struct iio_dev * indio_dev,uintptr_t private,const struct iio_chan_spec * chan,const char * buf,size_t len)124 static ssize_t ad5624r_write_dac_powerdown(struct iio_dev *indio_dev,
125 uintptr_t private, const struct iio_chan_spec *chan, const char *buf,
126 size_t len)
127 {
128 bool pwr_down;
129 int ret;
130 struct ad5624r_state *st = iio_priv(indio_dev);
131
132 ret = kstrtobool(buf, &pwr_down);
133 if (ret)
134 return ret;
135
136 if (pwr_down)
137 st->pwr_down_mask |= (1 << chan->channel);
138 else
139 st->pwr_down_mask &= ~(1 << chan->channel);
140
141 ret = ad5624r_spi_write(st->us, AD5624R_CMD_POWERDOWN_DAC, 0,
142 (st->pwr_down_mode << 4) |
143 st->pwr_down_mask, 16);
144
145 return ret ? ret : len;
146 }
147
148 static const struct iio_info ad5624r_info = {
149 .write_raw = ad5624r_write_raw,
150 .read_raw = ad5624r_read_raw,
151 };
152
153 static const struct iio_chan_spec_ext_info ad5624r_ext_info[] = {
154 {
155 .name = "powerdown",
156 .read = ad5624r_read_dac_powerdown,
157 .write = ad5624r_write_dac_powerdown,
158 .shared = IIO_SEPARATE,
159 },
160 IIO_ENUM("powerdown_mode", IIO_SHARED_BY_TYPE,
161 &ad5624r_powerdown_mode_enum),
162 IIO_ENUM_AVAILABLE("powerdown_mode", IIO_SHARED_BY_TYPE, &ad5624r_powerdown_mode_enum),
163 { },
164 };
165
166 #define AD5624R_CHANNEL(_chan, _bits) { \
167 .type = IIO_VOLTAGE, \
168 .indexed = 1, \
169 .output = 1, \
170 .channel = (_chan), \
171 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
172 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
173 .address = (_chan), \
174 .scan_type = { \
175 .sign = 'u', \
176 .realbits = (_bits), \
177 .storagebits = 16, \
178 .shift = 16 - (_bits), \
179 }, \
180 .ext_info = ad5624r_ext_info, \
181 }
182
183 #define DECLARE_AD5624R_CHANNELS(_name, _bits) \
184 const struct iio_chan_spec _name##_channels[] = { \
185 AD5624R_CHANNEL(0, _bits), \
186 AD5624R_CHANNEL(1, _bits), \
187 AD5624R_CHANNEL(2, _bits), \
188 AD5624R_CHANNEL(3, _bits), \
189 }
190
191 static DECLARE_AD5624R_CHANNELS(ad5624r, 12);
192 static DECLARE_AD5624R_CHANNELS(ad5644r, 14);
193 static DECLARE_AD5624R_CHANNELS(ad5664r, 16);
194
195 static const struct ad5624r_chip_info ad5624r_chip_info_tbl[] = {
196 [ID_AD5624R3] = {
197 .channels = ad5624r_channels,
198 .int_vref_mv = 1250,
199 },
200 [ID_AD5624R5] = {
201 .channels = ad5624r_channels,
202 .int_vref_mv = 2500,
203 },
204 [ID_AD5644R3] = {
205 .channels = ad5644r_channels,
206 .int_vref_mv = 1250,
207 },
208 [ID_AD5644R5] = {
209 .channels = ad5644r_channels,
210 .int_vref_mv = 2500,
211 },
212 [ID_AD5664R3] = {
213 .channels = ad5664r_channels,
214 .int_vref_mv = 1250,
215 },
216 [ID_AD5664R5] = {
217 .channels = ad5664r_channels,
218 .int_vref_mv = 2500,
219 },
220 };
221
ad5624r_probe(struct spi_device * spi)222 static int ad5624r_probe(struct spi_device *spi)
223 {
224 struct ad5624r_state *st;
225 struct iio_dev *indio_dev;
226 int ret, voltage_uv = 0;
227
228 indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
229 if (!indio_dev)
230 return -ENOMEM;
231 st = iio_priv(indio_dev);
232 st->reg = devm_regulator_get_optional(&spi->dev, "vref");
233 if (!IS_ERR(st->reg)) {
234 ret = regulator_enable(st->reg);
235 if (ret)
236 return ret;
237
238 ret = regulator_get_voltage(st->reg);
239 if (ret < 0)
240 goto error_disable_reg;
241
242 voltage_uv = ret;
243 } else {
244 if (PTR_ERR(st->reg) != -ENODEV)
245 return PTR_ERR(st->reg);
246 /* Backwards compatibility. This naming is not correct */
247 st->reg = devm_regulator_get_optional(&spi->dev, "vcc");
248 if (!IS_ERR(st->reg)) {
249 ret = regulator_enable(st->reg);
250 if (ret)
251 return ret;
252
253 ret = regulator_get_voltage(st->reg);
254 if (ret < 0)
255 goto error_disable_reg;
256
257 voltage_uv = ret;
258 }
259 }
260
261 spi_set_drvdata(spi, indio_dev);
262 st->chip_info =
263 &ad5624r_chip_info_tbl[spi_get_device_id(spi)->driver_data];
264
265 if (voltage_uv)
266 st->vref_mv = voltage_uv / 1000;
267 else
268 st->vref_mv = st->chip_info->int_vref_mv;
269
270 st->us = spi;
271
272 indio_dev->name = spi_get_device_id(spi)->name;
273 indio_dev->info = &ad5624r_info;
274 indio_dev->modes = INDIO_DIRECT_MODE;
275 indio_dev->channels = st->chip_info->channels;
276 indio_dev->num_channels = AD5624R_DAC_CHANNELS;
277
278 ret = ad5624r_spi_write(spi, AD5624R_CMD_INTERNAL_REFER_SETUP, 0,
279 !!voltage_uv, 16);
280 if (ret)
281 goto error_disable_reg;
282
283 ret = iio_device_register(indio_dev);
284 if (ret)
285 goto error_disable_reg;
286
287 return 0;
288
289 error_disable_reg:
290 if (!IS_ERR(st->reg))
291 regulator_disable(st->reg);
292
293 return ret;
294 }
295
ad5624r_remove(struct spi_device * spi)296 static void ad5624r_remove(struct spi_device *spi)
297 {
298 struct iio_dev *indio_dev = spi_get_drvdata(spi);
299 struct ad5624r_state *st = iio_priv(indio_dev);
300
301 iio_device_unregister(indio_dev);
302 if (!IS_ERR(st->reg))
303 regulator_disable(st->reg);
304 }
305
306 static const struct spi_device_id ad5624r_id[] = {
307 {"ad5624r3", ID_AD5624R3},
308 {"ad5644r3", ID_AD5644R3},
309 {"ad5664r3", ID_AD5664R3},
310 {"ad5624r5", ID_AD5624R5},
311 {"ad5644r5", ID_AD5644R5},
312 {"ad5664r5", ID_AD5664R5},
313 {}
314 };
315 MODULE_DEVICE_TABLE(spi, ad5624r_id);
316
317 static struct spi_driver ad5624r_driver = {
318 .driver = {
319 .name = "ad5624r",
320 },
321 .probe = ad5624r_probe,
322 .remove = ad5624r_remove,
323 .id_table = ad5624r_id,
324 };
325 module_spi_driver(ad5624r_driver);
326
327 MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
328 MODULE_DESCRIPTION("Analog Devices AD5624/44/64R DAC spi driver");
329 MODULE_LICENSE("GPL v2");
330