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11#include <linux/module.h>
12#include <linux/delay.h>
13#include <linux/i2c.h>
14#include <linux/iio/iio.h>
15#include <linux/iio/buffer.h>
16#include <linux/iio/trigger_consumer.h>
17#include <linux/iio/triggered_buffer.h>
18#include <asm/unaligned.h>
19
20
21#define DLH_START_SINGLE 0xAA
22
23
24#define DLH_STATUS_OK 0x40
25
26
27#define DLH_NUM_READ_BYTES 7
28#define DLH_NUM_DATA_BYTES 3
29#define DLH_NUM_PR_BITS 24
30#define DLH_NUM_TEMP_BITS 24
31
32
33#define DLH_SINGLE_DUT_MS 5
34
35enum dhl_ids {
36 dlhl60d,
37 dlhl60g,
38};
39
40struct dlh_info {
41 u8 osdig;
42 unsigned int fss;
43};
44
45struct dlh_state {
46 struct i2c_client *client;
47 struct dlh_info info;
48 bool use_interrupt;
49 struct completion completion;
50 u8 rx_buf[DLH_NUM_READ_BYTES] ____cacheline_aligned;
51};
52
53static struct dlh_info dlh_info_tbl[] = {
54 [dlhl60d] = {
55 .osdig = 2,
56 .fss = 120,
57 },
58 [dlhl60g] = {
59 .osdig = 10,
60 .fss = 60,
61 },
62};
63
64
65static int dlh_cmd_start_single(struct dlh_state *st)
66{
67 int ret;
68
69 ret = i2c_smbus_write_byte(st->client, DLH_START_SINGLE);
70 if (ret)
71 dev_err(&st->client->dev,
72 "%s: I2C write byte failed\n", __func__);
73
74 return ret;
75}
76
77static int dlh_cmd_read_data(struct dlh_state *st)
78{
79 int ret;
80
81 ret = i2c_master_recv(st->client, st->rx_buf, DLH_NUM_READ_BYTES);
82 if (ret < 0) {
83 dev_err(&st->client->dev,
84 "%s: I2C read block failed\n", __func__);
85 return ret;
86 }
87
88 if (st->rx_buf[0] != DLH_STATUS_OK) {
89 dev_err(&st->client->dev,
90 "%s: invalid status 0x%02x\n", __func__, st->rx_buf[0]);
91 return -EBUSY;
92 }
93
94 return 0;
95}
96
97static int dlh_start_capture_and_read(struct dlh_state *st)
98{
99 int ret;
100
101 if (st->use_interrupt)
102 reinit_completion(&st->completion);
103
104 ret = dlh_cmd_start_single(st);
105 if (ret)
106 return ret;
107
108 if (st->use_interrupt) {
109 ret = wait_for_completion_timeout(&st->completion,
110 msecs_to_jiffies(DLH_SINGLE_DUT_MS));
111 if (!ret) {
112 dev_err(&st->client->dev,
113 "%s: conversion timed out\n", __func__);
114 return -ETIMEDOUT;
115 }
116 } else {
117 mdelay(DLH_SINGLE_DUT_MS);
118 }
119
120 return dlh_cmd_read_data(st);
121}
122
123static int dlh_read_direct(struct dlh_state *st,
124 unsigned int *pressure, unsigned int *temperature)
125{
126 int ret;
127
128 ret = dlh_start_capture_and_read(st);
129 if (ret)
130 return ret;
131
132 *pressure = get_unaligned_be32(&st->rx_buf[1]) >> 8;
133 *temperature = get_unaligned_be32(&st->rx_buf[3]) &
134 GENMASK(DLH_NUM_TEMP_BITS - 1, 0);
135
136 return 0;
137}
138
139static int dlh_read_raw(struct iio_dev *indio_dev,
140 struct iio_chan_spec const *channel, int *value,
141 int *value2, long mask)
142{
143 struct dlh_state *st = iio_priv(indio_dev);
144 unsigned int pressure, temperature;
145 int ret;
146 s64 tmp;
147 s32 rem;
148
149 switch (mask) {
150 case IIO_CHAN_INFO_RAW:
151 ret = iio_device_claim_direct_mode(indio_dev);
152 if (ret)
153 return ret;
154
155 ret = dlh_read_direct(st, &pressure, &temperature);
156 iio_device_release_direct_mode(indio_dev);
157 if (ret)
158 return ret;
159
160 switch (channel->type) {
161 case IIO_PRESSURE:
162 *value = pressure;
163 return IIO_VAL_INT;
164
165 case IIO_TEMP:
166 *value = temperature;
167 return IIO_VAL_INT;
168
169 default:
170 return -EINVAL;
171 }
172 case IIO_CHAN_INFO_SCALE:
173 switch (channel->type) {
174 case IIO_PRESSURE:
175 tmp = div_s64(125LL * st->info.fss * 24909 * 100,
176 1 << DLH_NUM_PR_BITS);
177 tmp = div_s64_rem(tmp, 1000000000LL, &rem);
178 *value = tmp;
179 *value2 = rem;
180 return IIO_VAL_INT_PLUS_NANO;
181
182 case IIO_TEMP:
183 *value = 125 * 1000;
184 *value2 = DLH_NUM_TEMP_BITS;
185 return IIO_VAL_FRACTIONAL_LOG2;
186
187 default:
188 return -EINVAL;
189 }
190 case IIO_CHAN_INFO_OFFSET:
191 switch (channel->type) {
192 case IIO_PRESSURE:
193 *value = -125 * st->info.fss * 24909;
194 *value2 = 100 * st->info.osdig * 100000;
195 return IIO_VAL_FRACTIONAL;
196
197 case IIO_TEMP:
198 *value = -40 * 1000;
199 return IIO_VAL_INT;
200
201 default:
202 return -EINVAL;
203 }
204 }
205
206 return -EINVAL;
207}
208
209static const struct iio_info dlh_info = {
210 .read_raw = dlh_read_raw,
211};
212
213static const struct iio_chan_spec dlh_channels[] = {
214 {
215 .type = IIO_PRESSURE,
216 .indexed = 1,
217 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
218 .info_mask_shared_by_type =
219 BIT(IIO_CHAN_INFO_SCALE) |
220 BIT(IIO_CHAN_INFO_OFFSET),
221 .scan_index = 0,
222 .scan_type = {
223 .sign = 'u',
224 .realbits = DLH_NUM_PR_BITS,
225 .storagebits = 32,
226 .shift = 8,
227 .endianness = IIO_BE,
228 },
229 }, {
230 .type = IIO_TEMP,
231 .indexed = 1,
232 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
233 .info_mask_shared_by_type =
234 BIT(IIO_CHAN_INFO_SCALE) |
235 BIT(IIO_CHAN_INFO_OFFSET),
236 .scan_index = 1,
237 .scan_type = {
238 .sign = 'u',
239 .realbits = DLH_NUM_TEMP_BITS,
240 .storagebits = 32,
241 .shift = 8,
242 .endianness = IIO_BE,
243 },
244 }
245};
246
247static irqreturn_t dlh_trigger_handler(int irq, void *private)
248{
249 struct iio_poll_func *pf = private;
250 struct iio_dev *indio_dev = pf->indio_dev;
251 struct dlh_state *st = iio_priv(indio_dev);
252 int ret;
253 unsigned int chn, i = 0;
254 __be32 tmp_buf[2];
255
256 ret = dlh_start_capture_and_read(st);
257 if (ret)
258 goto out;
259
260 for_each_set_bit(chn, indio_dev->active_scan_mask,
261 indio_dev->masklength) {
262 memcpy(tmp_buf + i,
263 &st->rx_buf[1] + chn * DLH_NUM_DATA_BYTES,
264 DLH_NUM_DATA_BYTES);
265 i++;
266 }
267
268 iio_push_to_buffers(indio_dev, tmp_buf);
269
270out:
271 iio_trigger_notify_done(indio_dev->trig);
272
273 return IRQ_HANDLED;
274}
275
276static irqreturn_t dlh_interrupt(int irq, void *private)
277{
278 struct iio_dev *indio_dev = private;
279 struct dlh_state *st = iio_priv(indio_dev);
280
281 complete(&st->completion);
282
283 return IRQ_HANDLED;
284};
285
286static int dlh_probe(struct i2c_client *client,
287 const struct i2c_device_id *id)
288{
289 struct dlh_state *st;
290 struct iio_dev *indio_dev;
291 int ret;
292
293 if (!i2c_check_functionality(client->adapter,
294 I2C_FUNC_I2C | I2C_FUNC_SMBUS_WRITE_BYTE)) {
295 dev_err(&client->dev,
296 "adapter doesn't support required i2c functionality\n");
297 return -EOPNOTSUPP;
298 }
299
300 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*st));
301 if (!indio_dev) {
302 dev_err(&client->dev, "failed to allocate iio device\n");
303 return -ENOMEM;
304 }
305
306 i2c_set_clientdata(client, indio_dev);
307
308 st = iio_priv(indio_dev);
309 st->info = dlh_info_tbl[id->driver_data];
310 st->client = client;
311 st->use_interrupt = false;
312
313 indio_dev->name = id->name;
314 indio_dev->info = &dlh_info;
315 indio_dev->modes = INDIO_DIRECT_MODE;
316 indio_dev->channels = dlh_channels;
317 indio_dev->num_channels = ARRAY_SIZE(dlh_channels);
318
319 if (client->irq > 0) {
320 ret = devm_request_threaded_irq(&client->dev, client->irq,
321 dlh_interrupt, NULL,
322 IRQF_TRIGGER_RISING | IRQF_ONESHOT,
323 id->name, indio_dev);
324 if (ret) {
325 dev_err(&client->dev, "failed to allocate threaded irq");
326 return ret;
327 }
328
329 st->use_interrupt = true;
330 init_completion(&st->completion);
331 }
332
333 ret = devm_iio_triggered_buffer_setup(&client->dev, indio_dev,
334 NULL, &dlh_trigger_handler, NULL);
335 if (ret) {
336 dev_err(&client->dev, "failed to setup iio buffer\n");
337 return ret;
338 }
339
340 ret = devm_iio_device_register(&client->dev, indio_dev);
341 if (ret)
342 dev_err(&client->dev, "failed to register iio device\n");
343
344 return ret;
345}
346
347static const struct of_device_id dlh_of_match[] = {
348 { .compatible = "asc,dlhl60d" },
349 { .compatible = "asc,dlhl60g" },
350 {}
351};
352MODULE_DEVICE_TABLE(of, dlh_of_match);
353
354static const struct i2c_device_id dlh_id[] = {
355 { "dlhl60d", dlhl60d },
356 { "dlhl60g", dlhl60g },
357 {}
358};
359MODULE_DEVICE_TABLE(i2c, dlh_id);
360
361static struct i2c_driver dlh_driver = {
362 .driver = {
363 .name = "dlhl60d",
364 .of_match_table = dlh_of_match,
365 },
366 .probe = dlh_probe,
367 .id_table = dlh_id,
368};
369module_i2c_driver(dlh_driver);
370
371MODULE_AUTHOR("Tomislav Denis <tomislav.denis@avl.com>");
372MODULE_DESCRIPTION("Driver for All Sensors DLH series pressure sensors");
373MODULE_LICENSE("GPL v2");
374
