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iio: hid-sensors: Added ALS
[~andy/linux] / drivers / iio / light / hid-sensor-als.c
1 /*
2  * HID Sensors Driver
3  * Copyright (c) 2012, Intel Corporation.
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms and conditions of the GNU General Public License,
7  * version 2, as published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12  * more details.
13  *
14  * You should have received a copy of the GNU General Public License along with
15  * this program; if not, write to the Free Software Foundation, Inc.,
16  * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
17  *
18  */
19 #include <linux/device.h>
20 #include <linux/platform_device.h>
21 #include <linux/module.h>
22 #include <linux/interrupt.h>
23 #include <linux/irq.h>
24 #include <linux/slab.h>
25 #include <linux/hid-sensor-hub.h>
26 #include <linux/iio/iio.h>
27 #include <linux/iio/sysfs.h>
28 #include <linux/iio/buffer.h>
29 #include <linux/iio/trigger_consumer.h>
30 #include <linux/iio/triggered_buffer.h>
31 #include "../common/hid-sensors/hid-sensor-attributes.h"
32 #include "../common/hid-sensors/hid-sensor-trigger.h"
33
34 /*Format: HID-SENSOR-usage_id_in_hex*/
35 /*Usage ID from spec for Accelerometer-3D: 0x200041*/
36 #define DRIVER_NAME "HID-SENSOR-200041"
37
38 #define CHANNEL_SCAN_INDEX_ILLUM 0
39
40 struct als_state {
41         struct hid_sensor_hub_callbacks callbacks;
42         struct hid_sensor_iio_common common_attributes;
43         struct hid_sensor_hub_attribute_info als_illum;
44         u32 illum;
45 };
46
47 /* Channel definitions */
48 static const struct iio_chan_spec als_channels[] = {
49         {
50                 .type = IIO_INTENSITY,
51                 .modified = 1,
52                 .channel2 = IIO_MOD_LIGHT_BOTH,
53                 .info_mask = IIO_CHAN_INFO_OFFSET_SHARED_BIT |
54                 IIO_CHAN_INFO_SCALE_SHARED_BIT |
55                 IIO_CHAN_INFO_SAMP_FREQ_SHARED_BIT |
56                 IIO_CHAN_INFO_HYSTERESIS_SHARED_BIT,
57                 .scan_index = CHANNEL_SCAN_INDEX_ILLUM,
58         }
59 };
60
61 /* Adjust channel real bits based on report descriptor */
62 static void als_adjust_channel_bit_mask(struct iio_chan_spec *channels,
63                                         int channel, int size)
64 {
65         channels[channel].scan_type.sign = 's';
66         /* Real storage bits will change based on the report desc. */
67         channels[channel].scan_type.realbits = size * 8;
68         /* Maximum size of a sample to capture is u32 */
69         channels[channel].scan_type.storagebits = sizeof(u32) * 8;
70 }
71
72 /* Channel read_raw handler */
73 static int als_read_raw(struct iio_dev *indio_dev,
74                               struct iio_chan_spec const *chan,
75                               int *val, int *val2,
76                               long mask)
77 {
78         struct als_state *als_state = iio_priv(indio_dev);
79         int report_id = -1;
80         u32 address;
81         int ret;
82         int ret_type;
83
84         *val = 0;
85         *val2 = 0;
86         switch (mask) {
87         case 0:
88                 switch (chan->scan_index) {
89                 case  CHANNEL_SCAN_INDEX_ILLUM:
90                         report_id = als_state->als_illum.report_id;
91                         address =
92                         HID_USAGE_SENSOR_LIGHT_ILLUM;
93                         break;
94                 default:
95                         report_id = -1;
96                         break;
97                 }
98                 if (report_id >= 0)
99                         *val = sensor_hub_input_attr_get_raw_value(
100                                 als_state->common_attributes.hsdev,
101                                 HID_USAGE_SENSOR_ALS, address,
102                                 report_id);
103                 else {
104                         *val = 0;
105                         return -EINVAL;
106                 }
107                 ret_type = IIO_VAL_INT;
108                 break;
109         case IIO_CHAN_INFO_SCALE:
110                 *val = als_state->als_illum.units;
111                 ret_type = IIO_VAL_INT;
112                 break;
113         case IIO_CHAN_INFO_OFFSET:
114                 *val = hid_sensor_convert_exponent(
115                                 als_state->als_illum.unit_expo);
116                 ret_type = IIO_VAL_INT;
117                 break;
118         case IIO_CHAN_INFO_SAMP_FREQ:
119                 ret = hid_sensor_read_samp_freq_value(
120                                 &als_state->common_attributes, val, val2);
121                 ret_type = IIO_VAL_INT_PLUS_MICRO;
122                 break;
123         case IIO_CHAN_INFO_HYSTERESIS:
124                 ret = hid_sensor_read_raw_hyst_value(
125                                 &als_state->common_attributes, val, val2);
126                 ret_type = IIO_VAL_INT_PLUS_MICRO;
127                 break;
128         default:
129                 ret_type = -EINVAL;
130                 break;
131         }
132
133         return ret_type;
134 }
135
136 /* Channel write_raw handler */
137 static int als_write_raw(struct iio_dev *indio_dev,
138                                struct iio_chan_spec const *chan,
139                                int val,
140                                int val2,
141                                long mask)
142 {
143         struct als_state *als_state = iio_priv(indio_dev);
144         int ret = 0;
145
146         switch (mask) {
147         case IIO_CHAN_INFO_SAMP_FREQ:
148                 ret = hid_sensor_write_samp_freq_value(
149                                 &als_state->common_attributes, val, val2);
150                 break;
151         case IIO_CHAN_INFO_HYSTERESIS:
152                 ret = hid_sensor_write_raw_hyst_value(
153                                 &als_state->common_attributes, val, val2);
154                 break;
155         default:
156                 ret = -EINVAL;
157         }
158
159         return ret;
160 }
161
162 static int als_write_raw_get_fmt(struct iio_dev *indio_dev,
163                                struct iio_chan_spec const *chan,
164                                long mask)
165 {
166         return IIO_VAL_INT_PLUS_MICRO;
167 }
168
169 static const struct iio_info als_info = {
170         .driver_module = THIS_MODULE,
171         .read_raw = &als_read_raw,
172         .write_raw = &als_write_raw,
173         .write_raw_get_fmt = &als_write_raw_get_fmt,
174 };
175
176 /* Function to push data to buffer */
177 static void hid_sensor_push_data(struct iio_dev *indio_dev, u8 *data, int len)
178 {
179         struct iio_buffer *buffer = indio_dev->buffer;
180         s64 timestamp = iio_get_time_ns();
181         int datum_sz;
182
183         dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n");
184         if (!buffer) {
185                 dev_err(&indio_dev->dev, "Buffer == NULL\n");
186                 return;
187         }
188         datum_sz = buffer->access->get_bytes_per_datum(buffer);
189         if (len > datum_sz) {
190                 dev_err(&indio_dev->dev, "Datum size mismatch %d:%d\n", len,
191                                 datum_sz);
192                 return;
193         }
194         buffer->access->store_to(buffer, (u8 *)data, timestamp);
195 }
196
197 /* Callback handler to send event after all samples are received and captured */
198 static int als_proc_event(struct hid_sensor_hub_device *hsdev,
199                                 unsigned usage_id,
200                                 void *priv)
201 {
202         struct iio_dev *indio_dev = platform_get_drvdata(priv);
203         struct als_state *als_state = iio_priv(indio_dev);
204
205         dev_dbg(&indio_dev->dev, "als_proc_event [%d]\n",
206                                 als_state->common_attributes.data_ready);
207         if (als_state->common_attributes.data_ready)
208                 hid_sensor_push_data(indio_dev,
209                                 (u8 *)&als_state->illum,
210                                 sizeof(als_state->illum));
211
212         return 0;
213 }
214
215 /* Capture samples in local storage */
216 static int als_capture_sample(struct hid_sensor_hub_device *hsdev,
217                                 unsigned usage_id,
218                                 size_t raw_len, char *raw_data,
219                                 void *priv)
220 {
221         struct iio_dev *indio_dev = platform_get_drvdata(priv);
222         struct als_state *als_state = iio_priv(indio_dev);
223         int ret = -EINVAL;
224
225         switch (usage_id) {
226         case HID_USAGE_SENSOR_LIGHT_ILLUM:
227                 als_state->illum = *(u32 *)raw_data;
228                 ret = 0;
229                 break;
230         default:
231                 break;
232         }
233
234         return ret;
235 }
236
237 /* Parse report which is specific to an usage id*/
238 static int als_parse_report(struct platform_device *pdev,
239                                 struct hid_sensor_hub_device *hsdev,
240                                 struct iio_chan_spec *channels,
241                                 unsigned usage_id,
242                                 struct als_state *st)
243 {
244         int ret;
245
246         ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
247                         usage_id,
248                         HID_USAGE_SENSOR_LIGHT_ILLUM,
249                         &st->als_illum);
250         if (ret < 0)
251                 return ret;
252         als_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_ILLUM,
253                                         st->als_illum.size);
254
255         dev_dbg(&pdev->dev, "als %x:%x\n", st->als_illum.index,
256                         st->als_illum.report_id);
257
258         return ret;
259 }
260
261 /* Function to initialize the processing for usage id */
262 static int __devinit hid_als_probe(struct platform_device *pdev)
263 {
264         int ret = 0;
265         static const char *name = "als";
266         struct iio_dev *indio_dev;
267         struct als_state *als_state;
268         struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
269         struct iio_chan_spec *channels;
270
271         indio_dev = iio_device_alloc(sizeof(struct als_state));
272         if (indio_dev == NULL) {
273                 ret = -ENOMEM;
274                 goto error_ret;
275         }
276         platform_set_drvdata(pdev, indio_dev);
277
278         als_state = iio_priv(indio_dev);
279         als_state->common_attributes.hsdev = hsdev;
280         als_state->common_attributes.pdev = pdev;
281
282         ret = hid_sensor_parse_common_attributes(hsdev, HID_USAGE_SENSOR_ALS,
283                                         &als_state->common_attributes);
284         if (ret) {
285                 dev_err(&pdev->dev, "failed to setup common attributes\n");
286                 goto error_free_dev;
287         }
288
289         channels = kmemdup(als_channels,
290                                         sizeof(als_channels),
291                                         GFP_KERNEL);
292         if (!channels) {
293                 dev_err(&pdev->dev, "failed to duplicate channels\n");
294                 goto error_free_dev;
295         }
296
297         ret = als_parse_report(pdev, hsdev, channels,
298                                 HID_USAGE_SENSOR_ALS, als_state);
299         if (ret) {
300                 dev_err(&pdev->dev, "failed to setup attributes\n");
301                 goto error_free_dev_mem;
302         }
303
304         indio_dev->channels = channels;
305         indio_dev->num_channels =
306                                 ARRAY_SIZE(als_channels);
307         indio_dev->dev.parent = &pdev->dev;
308         indio_dev->info = &als_info;
309         indio_dev->name = name;
310         indio_dev->modes = INDIO_DIRECT_MODE;
311
312         ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
313                 NULL, NULL);
314         if (ret) {
315                 dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
316                 goto error_free_dev_mem;
317         }
318         als_state->common_attributes.data_ready = false;
319         ret = hid_sensor_setup_trigger(indio_dev, name,
320                                 &als_state->common_attributes);
321         if (ret < 0) {
322                 dev_err(&pdev->dev, "trigger setup failed\n");
323                 goto error_unreg_buffer_funcs;
324         }
325
326         ret = iio_device_register(indio_dev);
327         if (ret) {
328                 dev_err(&pdev->dev, "device register failed\n");
329                 goto error_remove_trigger;
330         }
331
332         als_state->callbacks.send_event = als_proc_event;
333         als_state->callbacks.capture_sample = als_capture_sample;
334         als_state->callbacks.pdev = pdev;
335         ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_ALS,
336                                         &als_state->callbacks);
337         if (ret < 0) {
338                 dev_err(&pdev->dev, "callback reg failed\n");
339                 goto error_iio_unreg;
340         }
341
342         return ret;
343
344 error_iio_unreg:
345         iio_device_unregister(indio_dev);
346 error_remove_trigger:
347         hid_sensor_remove_trigger(indio_dev);
348 error_unreg_buffer_funcs:
349         iio_triggered_buffer_cleanup(indio_dev);
350 error_free_dev_mem:
351         kfree(indio_dev->channels);
352 error_free_dev:
353         iio_device_free(indio_dev);
354 error_ret:
355         return ret;
356 }
357
358 /* Function to deinitialize the processing for usage id */
359 static int __devinit hid_als_remove(struct platform_device *pdev)
360 {
361         struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
362         struct iio_dev *indio_dev = platform_get_drvdata(pdev);
363
364         sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_ALS);
365         iio_device_unregister(indio_dev);
366         hid_sensor_remove_trigger(indio_dev);
367         iio_triggered_buffer_cleanup(indio_dev);
368         kfree(indio_dev->channels);
369         iio_device_free(indio_dev);
370
371         return 0;
372 }
373
374 static struct platform_driver hid_als_platform_driver = {
375         .driver = {
376                 .name   = DRIVER_NAME,
377                 .owner  = THIS_MODULE,
378         },
379         .probe          = hid_als_probe,
380         .remove         = hid_als_remove,
381 };
382 module_platform_driver(hid_als_platform_driver);
383
384 MODULE_DESCRIPTION("HID Sensor ALS");
385 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@intel.com>");
386 MODULE_LICENSE("GPL");