1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * AD8366 and similar Gain Amplifiers |
4 | * This driver supports the following gain amplifiers: |
5 | * AD8366 Dual-Digital Variable Gain Amplifier (VGA) |
6 | * ADA4961 BiCMOS RF Digital Gain Amplifier (DGA) |
7 | * ADL5240 Digitally controlled variable gain amplifier (VGA) |
8 | * HMC792A 0.25 dB LSB GaAs MMIC 6-Bit Digital Attenuator |
9 | * HMC1119 0.25 dB LSB, 7-Bit, Silicon Digital Attenuator |
10 | * |
11 | * Copyright 2012-2019 Analog Devices Inc. |
12 | */ |
13 | |
14 | #include <linux/device.h> |
15 | #include <linux/kernel.h> |
16 | #include <linux/slab.h> |
17 | #include <linux/sysfs.h> |
18 | #include <linux/spi/spi.h> |
19 | #include <linux/regulator/consumer.h> |
20 | #include <linux/gpio/consumer.h> |
21 | #include <linux/err.h> |
22 | #include <linux/module.h> |
23 | #include <linux/bitrev.h> |
24 | |
25 | #include <linux/iio/iio.h> |
26 | #include <linux/iio/sysfs.h> |
27 | |
28 | enum ad8366_type { |
29 | ID_AD8366, |
30 | ID_ADA4961, |
31 | ID_ADL5240, |
32 | ID_HMC792, |
33 | ID_HMC1119, |
34 | }; |
35 | |
36 | struct ad8366_info { |
37 | int gain_min; |
38 | int gain_max; |
39 | }; |
40 | |
41 | struct ad8366_state { |
42 | struct spi_device *spi; |
43 | struct regulator *reg; |
44 | struct mutex lock; /* protect sensor state */ |
45 | struct gpio_desc *reset_gpio; |
46 | unsigned char ch[2]; |
47 | enum ad8366_type type; |
48 | struct ad8366_info *info; |
49 | /* |
50 | * DMA (thus cache coherency maintenance) may require the |
51 | * transfer buffers to live in their own cache lines. |
52 | */ |
53 | unsigned char data[2] __aligned(IIO_DMA_MINALIGN); |
54 | }; |
55 | |
56 | static struct ad8366_info ad8366_infos[] = { |
57 | [ID_AD8366] = { |
58 | .gain_min = 4500, |
59 | .gain_max = 20500, |
60 | }, |
61 | [ID_ADA4961] = { |
62 | .gain_min = -6000, |
63 | .gain_max = 15000, |
64 | }, |
65 | [ID_ADL5240] = { |
66 | .gain_min = -11500, |
67 | .gain_max = 20000, |
68 | }, |
69 | [ID_HMC792] = { |
70 | .gain_min = -15750, |
71 | .gain_max = 0, |
72 | }, |
73 | [ID_HMC1119] = { |
74 | .gain_min = -31750, |
75 | .gain_max = 0, |
76 | }, |
77 | }; |
78 | |
79 | static int ad8366_write(struct iio_dev *indio_dev, |
80 | unsigned char ch_a, unsigned char ch_b) |
81 | { |
82 | struct ad8366_state *st = iio_priv(indio_dev); |
83 | int ret; |
84 | |
85 | switch (st->type) { |
86 | case ID_AD8366: |
87 | ch_a = bitrev8(ch_a & 0x3F); |
88 | ch_b = bitrev8(ch_b & 0x3F); |
89 | |
90 | st->data[0] = ch_b >> 4; |
91 | st->data[1] = (ch_b << 4) | (ch_a >> 2); |
92 | break; |
93 | case ID_ADA4961: |
94 | st->data[0] = ch_a & 0x1F; |
95 | break; |
96 | case ID_ADL5240: |
97 | st->data[0] = (ch_a & 0x3F); |
98 | break; |
99 | case ID_HMC792: |
100 | case ID_HMC1119: |
101 | st->data[0] = ch_a; |
102 | break; |
103 | } |
104 | |
105 | ret = spi_write(spi: st->spi, buf: st->data, len: indio_dev->num_channels); |
106 | if (ret < 0) |
107 | dev_err(&indio_dev->dev, "write failed (%d)" , ret); |
108 | |
109 | return ret; |
110 | } |
111 | |
112 | static int ad8366_read_raw(struct iio_dev *indio_dev, |
113 | struct iio_chan_spec const *chan, |
114 | int *val, |
115 | int *val2, |
116 | long m) |
117 | { |
118 | struct ad8366_state *st = iio_priv(indio_dev); |
119 | int ret; |
120 | int code, gain = 0; |
121 | |
122 | mutex_lock(&st->lock); |
123 | switch (m) { |
124 | case IIO_CHAN_INFO_HARDWAREGAIN: |
125 | code = st->ch[chan->channel]; |
126 | |
127 | switch (st->type) { |
128 | case ID_AD8366: |
129 | gain = code * 253 + 4500; |
130 | break; |
131 | case ID_ADA4961: |
132 | gain = 15000 - code * 1000; |
133 | break; |
134 | case ID_ADL5240: |
135 | gain = 20000 - 31500 + code * 500; |
136 | break; |
137 | case ID_HMC792: |
138 | gain = -1 * code * 500; |
139 | break; |
140 | case ID_HMC1119: |
141 | gain = -1 * code * 250; |
142 | break; |
143 | } |
144 | |
145 | /* Values in dB */ |
146 | *val = gain / 1000; |
147 | *val2 = (gain % 1000) * 1000; |
148 | |
149 | ret = IIO_VAL_INT_PLUS_MICRO_DB; |
150 | break; |
151 | default: |
152 | ret = -EINVAL; |
153 | } |
154 | mutex_unlock(lock: &st->lock); |
155 | |
156 | return ret; |
157 | }; |
158 | |
159 | static int ad8366_write_raw(struct iio_dev *indio_dev, |
160 | struct iio_chan_spec const *chan, |
161 | int val, |
162 | int val2, |
163 | long mask) |
164 | { |
165 | struct ad8366_state *st = iio_priv(indio_dev); |
166 | struct ad8366_info *inf = st->info; |
167 | int code = 0, gain; |
168 | int ret; |
169 | |
170 | /* Values in dB */ |
171 | if (val < 0) |
172 | gain = (val * 1000) - (val2 / 1000); |
173 | else |
174 | gain = (val * 1000) + (val2 / 1000); |
175 | |
176 | if (gain > inf->gain_max || gain < inf->gain_min) |
177 | return -EINVAL; |
178 | |
179 | switch (st->type) { |
180 | case ID_AD8366: |
181 | code = (gain - 4500) / 253; |
182 | break; |
183 | case ID_ADA4961: |
184 | code = (15000 - gain) / 1000; |
185 | break; |
186 | case ID_ADL5240: |
187 | code = ((gain - 500 - 20000) / 500) & 0x3F; |
188 | break; |
189 | case ID_HMC792: |
190 | code = (abs(gain) / 500) & 0x3F; |
191 | break; |
192 | case ID_HMC1119: |
193 | code = (abs(gain) / 250) & 0x7F; |
194 | break; |
195 | } |
196 | |
197 | mutex_lock(&st->lock); |
198 | switch (mask) { |
199 | case IIO_CHAN_INFO_HARDWAREGAIN: |
200 | st->ch[chan->channel] = code; |
201 | ret = ad8366_write(indio_dev, ch_a: st->ch[0], ch_b: st->ch[1]); |
202 | break; |
203 | default: |
204 | ret = -EINVAL; |
205 | } |
206 | mutex_unlock(lock: &st->lock); |
207 | |
208 | return ret; |
209 | } |
210 | |
211 | static int ad8366_write_raw_get_fmt(struct iio_dev *indio_dev, |
212 | struct iio_chan_spec const *chan, |
213 | long mask) |
214 | { |
215 | switch (mask) { |
216 | case IIO_CHAN_INFO_HARDWAREGAIN: |
217 | return IIO_VAL_INT_PLUS_MICRO_DB; |
218 | default: |
219 | return -EINVAL; |
220 | } |
221 | } |
222 | |
223 | static const struct iio_info ad8366_info = { |
224 | .read_raw = &ad8366_read_raw, |
225 | .write_raw = &ad8366_write_raw, |
226 | .write_raw_get_fmt = &ad8366_write_raw_get_fmt, |
227 | }; |
228 | |
229 | #define AD8366_CHAN(_channel) { \ |
230 | .type = IIO_VOLTAGE, \ |
231 | .output = 1, \ |
232 | .indexed = 1, \ |
233 | .channel = _channel, \ |
234 | .info_mask_separate = BIT(IIO_CHAN_INFO_HARDWAREGAIN),\ |
235 | } |
236 | |
237 | static const struct iio_chan_spec ad8366_channels[] = { |
238 | AD8366_CHAN(0), |
239 | AD8366_CHAN(1), |
240 | }; |
241 | |
242 | static const struct iio_chan_spec ada4961_channels[] = { |
243 | AD8366_CHAN(0), |
244 | }; |
245 | |
246 | static int ad8366_probe(struct spi_device *spi) |
247 | { |
248 | struct iio_dev *indio_dev; |
249 | struct ad8366_state *st; |
250 | int ret; |
251 | |
252 | indio_dev = devm_iio_device_alloc(parent: &spi->dev, sizeof_priv: sizeof(*st)); |
253 | if (indio_dev == NULL) |
254 | return -ENOMEM; |
255 | |
256 | st = iio_priv(indio_dev); |
257 | |
258 | st->reg = devm_regulator_get(dev: &spi->dev, id: "vcc" ); |
259 | if (!IS_ERR(ptr: st->reg)) { |
260 | ret = regulator_enable(regulator: st->reg); |
261 | if (ret) |
262 | return ret; |
263 | } |
264 | |
265 | spi_set_drvdata(spi, data: indio_dev); |
266 | mutex_init(&st->lock); |
267 | st->spi = spi; |
268 | st->type = spi_get_device_id(sdev: spi)->driver_data; |
269 | |
270 | switch (st->type) { |
271 | case ID_AD8366: |
272 | indio_dev->channels = ad8366_channels; |
273 | indio_dev->num_channels = ARRAY_SIZE(ad8366_channels); |
274 | break; |
275 | case ID_ADA4961: |
276 | case ID_ADL5240: |
277 | case ID_HMC792: |
278 | case ID_HMC1119: |
279 | st->reset_gpio = devm_gpiod_get_optional(dev: &spi->dev, con_id: "reset" , flags: GPIOD_OUT_HIGH); |
280 | if (IS_ERR(ptr: st->reset_gpio)) { |
281 | ret = PTR_ERR(ptr: st->reset_gpio); |
282 | goto error_disable_reg; |
283 | } |
284 | indio_dev->channels = ada4961_channels; |
285 | indio_dev->num_channels = ARRAY_SIZE(ada4961_channels); |
286 | break; |
287 | default: |
288 | dev_err(&spi->dev, "Invalid device ID\n" ); |
289 | ret = -EINVAL; |
290 | goto error_disable_reg; |
291 | } |
292 | |
293 | st->info = &ad8366_infos[st->type]; |
294 | indio_dev->name = spi_get_device_id(sdev: spi)->name; |
295 | indio_dev->info = &ad8366_info; |
296 | indio_dev->modes = INDIO_DIRECT_MODE; |
297 | |
298 | ret = ad8366_write(indio_dev, ch_a: 0, ch_b: 0); |
299 | if (ret < 0) |
300 | goto error_disable_reg; |
301 | |
302 | ret = iio_device_register(indio_dev); |
303 | if (ret) |
304 | goto error_disable_reg; |
305 | |
306 | return 0; |
307 | |
308 | error_disable_reg: |
309 | if (!IS_ERR(ptr: st->reg)) |
310 | regulator_disable(regulator: st->reg); |
311 | |
312 | return ret; |
313 | } |
314 | |
315 | static void ad8366_remove(struct spi_device *spi) |
316 | { |
317 | struct iio_dev *indio_dev = spi_get_drvdata(spi); |
318 | struct ad8366_state *st = iio_priv(indio_dev); |
319 | struct regulator *reg = st->reg; |
320 | |
321 | iio_device_unregister(indio_dev); |
322 | |
323 | if (!IS_ERR(ptr: reg)) |
324 | regulator_disable(regulator: reg); |
325 | } |
326 | |
327 | static const struct spi_device_id ad8366_id[] = { |
328 | {"ad8366" , ID_AD8366}, |
329 | {"ada4961" , ID_ADA4961}, |
330 | {"adl5240" , ID_ADL5240}, |
331 | {"hmc792a" , ID_HMC792}, |
332 | {"hmc1119" , ID_HMC1119}, |
333 | {} |
334 | }; |
335 | MODULE_DEVICE_TABLE(spi, ad8366_id); |
336 | |
337 | static struct spi_driver ad8366_driver = { |
338 | .driver = { |
339 | .name = KBUILD_MODNAME, |
340 | }, |
341 | .probe = ad8366_probe, |
342 | .remove = ad8366_remove, |
343 | .id_table = ad8366_id, |
344 | }; |
345 | |
346 | module_spi_driver(ad8366_driver); |
347 | |
348 | MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>" ); |
349 | MODULE_DESCRIPTION("Analog Devices AD8366 and similar Gain Amplifiers" ); |
350 | MODULE_LICENSE("GPL v2" ); |
351 | |