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/delay.h>
26 #include <linux/hid-sensor-hub.h>
27 #include <linux/iio/iio.h>
28 #include <linux/iio/sysfs.h>
29 #include <linux/iio/buffer.h>
30 #include <linux/iio/trigger_consumer.h>
31 #include <linux/iio/triggered_buffer.h>
32 #include "../common/hid-sensors/hid-sensor-trigger.h"
33 
34 enum magn_3d_channel {
35 	CHANNEL_SCAN_INDEX_X,
36 	CHANNEL_SCAN_INDEX_Y,
37 	CHANNEL_SCAN_INDEX_Z,
38 	CHANNEL_SCAN_INDEX_NORTH_MAGN_TILT_COMP,
39 	CHANNEL_SCAN_INDEX_NORTH_TRUE_TILT_COMP,
40 	CHANNEL_SCAN_INDEX_NORTH_MAGN,
41 	CHANNEL_SCAN_INDEX_NORTH_TRUE,
42 	MAGN_3D_CHANNEL_MAX,
43 };
44 
45 struct magn_3d_state {
46 	struct hid_sensor_hub_callbacks callbacks;
47 	struct hid_sensor_common common_attributes;
48 	struct hid_sensor_hub_attribute_info magn[MAGN_3D_CHANNEL_MAX];
49 
50 	/* dynamically sized array to hold sensor values */
51 	u32 *iio_vals;
52 	/* array of pointers to sensor value */
53 	u32 *magn_val_addr[MAGN_3D_CHANNEL_MAX];
54 
55 	int scale_pre_decml;
56 	int scale_post_decml;
57 	int scale_precision;
58 	int value_offset;
59 };
60 
61 static const u32 magn_3d_addresses[MAGN_3D_CHANNEL_MAX] = {
62 	HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_X_AXIS,
63 	HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_Y_AXIS,
64 	HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_Z_AXIS,
65 	HID_USAGE_SENSOR_ORIENT_COMP_MAGN_NORTH,
66 	HID_USAGE_SENSOR_ORIENT_COMP_TRUE_NORTH,
67 	HID_USAGE_SENSOR_ORIENT_MAGN_NORTH,
68 	HID_USAGE_SENSOR_ORIENT_TRUE_NORTH,
69 };
70 
71 /* Channel definitions */
72 static const struct iio_chan_spec magn_3d_channels[] = {
73 	{
74 		.type = IIO_MAGN,
75 		.modified = 1,
76 		.channel2 = IIO_MOD_X,
77 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
78 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
79 		BIT(IIO_CHAN_INFO_SCALE) |
80 		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
81 		BIT(IIO_CHAN_INFO_HYSTERESIS),
82 	}, {
83 		.type = IIO_MAGN,
84 		.modified = 1,
85 		.channel2 = IIO_MOD_Y,
86 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
87 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
88 		BIT(IIO_CHAN_INFO_SCALE) |
89 		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
90 		BIT(IIO_CHAN_INFO_HYSTERESIS),
91 	}, {
92 		.type = IIO_MAGN,
93 		.modified = 1,
94 		.channel2 = IIO_MOD_Z,
95 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
96 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
97 		BIT(IIO_CHAN_INFO_SCALE) |
98 		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
99 		BIT(IIO_CHAN_INFO_HYSTERESIS),
100 	}, {
101 		.type = IIO_ROT,
102 		.modified = 1,
103 		.channel2 = IIO_MOD_NORTH_MAGN_TILT_COMP,
104 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
105 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
106 		BIT(IIO_CHAN_INFO_SCALE) |
107 		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
108 		BIT(IIO_CHAN_INFO_HYSTERESIS),
109 	}, {
110 		.type = IIO_ROT,
111 		.modified = 1,
112 		.channel2 = IIO_MOD_NORTH_TRUE_TILT_COMP,
113 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
114 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
115 		BIT(IIO_CHAN_INFO_SCALE) |
116 		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
117 		BIT(IIO_CHAN_INFO_HYSTERESIS),
118 	}, {
119 		.type = IIO_ROT,
120 		.modified = 1,
121 		.channel2 = IIO_MOD_NORTH_MAGN,
122 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
123 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
124 		BIT(IIO_CHAN_INFO_SCALE) |
125 		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
126 		BIT(IIO_CHAN_INFO_HYSTERESIS),
127 	}, {
128 		.type = IIO_ROT,
129 		.modified = 1,
130 		.channel2 = IIO_MOD_NORTH_TRUE,
131 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
132 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
133 		BIT(IIO_CHAN_INFO_SCALE) |
134 		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
135 		BIT(IIO_CHAN_INFO_HYSTERESIS),
136 	}
137 };
138 
139 /* Adjust channel real bits based on report descriptor */
140 static void magn_3d_adjust_channel_bit_mask(struct iio_chan_spec *channels,
141 						int channel, int size)
142 {
143 	channels[channel].scan_type.sign = 's';
144 	/* Real storage bits will change based on the report desc. */
145 	channels[channel].scan_type.realbits = size * 8;
146 	/* Maximum size of a sample to capture is u32 */
147 	channels[channel].scan_type.storagebits = sizeof(u32) * 8;
148 }
149 
150 /* Channel read_raw handler */
151 static int magn_3d_read_raw(struct iio_dev *indio_dev,
152 			      struct iio_chan_spec const *chan,
153 			      int *val, int *val2,
154 			      long mask)
155 {
156 	struct magn_3d_state *magn_state = iio_priv(indio_dev);
157 	int report_id = -1;
158 	u32 address;
159 	int ret_type;
160 	s32 poll_value;
161 
162 	*val = 0;
163 	*val2 = 0;
164 	switch (mask) {
165 	case 0:
166 		poll_value = hid_sensor_read_poll_value(
167 					&magn_state->common_attributes);
168 		if (poll_value < 0)
169 				return -EINVAL;
170 
171 		hid_sensor_power_state(&magn_state->common_attributes, true);
172 		msleep_interruptible(poll_value * 2);
173 
174 		report_id =
175 			magn_state->magn[chan->address].report_id;
176 		address = magn_3d_addresses[chan->address];
177 		if (report_id >= 0)
178 			*val = sensor_hub_input_attr_get_raw_value(
179 				magn_state->common_attributes.hsdev,
180 				HID_USAGE_SENSOR_COMPASS_3D, address,
181 				report_id);
182 		else {
183 			*val = 0;
184 			hid_sensor_power_state(&magn_state->common_attributes,
185 						false);
186 			return -EINVAL;
187 		}
188 		hid_sensor_power_state(&magn_state->common_attributes, false);
189 		ret_type = IIO_VAL_INT;
190 		break;
191 	case IIO_CHAN_INFO_SCALE:
192 		*val = magn_state->scale_pre_decml;
193 		*val2 = magn_state->scale_post_decml;
194 		ret_type = magn_state->scale_precision;
195 		break;
196 	case IIO_CHAN_INFO_OFFSET:
197 		*val = magn_state->value_offset;
198 		ret_type = IIO_VAL_INT;
199 		break;
200 	case IIO_CHAN_INFO_SAMP_FREQ:
201 		ret_type = hid_sensor_read_samp_freq_value(
202 			&magn_state->common_attributes, val, val2);
203 		break;
204 	case IIO_CHAN_INFO_HYSTERESIS:
205 		ret_type = hid_sensor_read_raw_hyst_value(
206 			&magn_state->common_attributes, val, val2);
207 		break;
208 	default:
209 		ret_type = -EINVAL;
210 		break;
211 	}
212 
213 	return ret_type;
214 }
215 
216 /* Channel write_raw handler */
217 static int magn_3d_write_raw(struct iio_dev *indio_dev,
218 			       struct iio_chan_spec const *chan,
219 			       int val,
220 			       int val2,
221 			       long mask)
222 {
223 	struct magn_3d_state *magn_state = iio_priv(indio_dev);
224 	int ret = 0;
225 
226 	switch (mask) {
227 	case IIO_CHAN_INFO_SAMP_FREQ:
228 		ret = hid_sensor_write_samp_freq_value(
229 				&magn_state->common_attributes, val, val2);
230 		break;
231 	case IIO_CHAN_INFO_HYSTERESIS:
232 		ret = hid_sensor_write_raw_hyst_value(
233 				&magn_state->common_attributes, val, val2);
234 		break;
235 	default:
236 		ret = -EINVAL;
237 	}
238 
239 	return ret;
240 }
241 
242 static const struct iio_info magn_3d_info = {
243 	.driver_module = THIS_MODULE,
244 	.read_raw = &magn_3d_read_raw,
245 	.write_raw = &magn_3d_write_raw,
246 };
247 
248 /* Function to push data to buffer */
249 static void hid_sensor_push_data(struct iio_dev *indio_dev, const void *data)
250 {
251 	dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n");
252 	iio_push_to_buffers(indio_dev, data);
253 }
254 
255 /* Callback handler to send event after all samples are received and captured */
256 static int magn_3d_proc_event(struct hid_sensor_hub_device *hsdev,
257 				unsigned usage_id,
258 				void *priv)
259 {
260 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
261 	struct magn_3d_state *magn_state = iio_priv(indio_dev);
262 
263 	dev_dbg(&indio_dev->dev, "magn_3d_proc_event\n");
264 	if (atomic_read(&magn_state->common_attributes.data_ready))
265 		hid_sensor_push_data(indio_dev, magn_state->iio_vals);
266 
267 	return 0;
268 }
269 
270 /* Capture samples in local storage */
271 static int magn_3d_capture_sample(struct hid_sensor_hub_device *hsdev,
272 				unsigned usage_id,
273 				size_t raw_len, char *raw_data,
274 				void *priv)
275 {
276 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
277 	struct magn_3d_state *magn_state = iio_priv(indio_dev);
278 	int offset;
279 	int ret = 0;
280 	u32 *iio_val = NULL;
281 
282 	switch (usage_id) {
283 	case HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_X_AXIS:
284 	case HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_Y_AXIS:
285 	case HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_Z_AXIS:
286 		offset = (usage_id - HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_X_AXIS)
287 				+ CHANNEL_SCAN_INDEX_X;
288 	break;
289 	case HID_USAGE_SENSOR_ORIENT_COMP_MAGN_NORTH:
290 	case HID_USAGE_SENSOR_ORIENT_COMP_TRUE_NORTH:
291 	case HID_USAGE_SENSOR_ORIENT_MAGN_NORTH:
292 	case HID_USAGE_SENSOR_ORIENT_TRUE_NORTH:
293 		offset = (usage_id - HID_USAGE_SENSOR_ORIENT_COMP_MAGN_NORTH)
294 				+ CHANNEL_SCAN_INDEX_NORTH_MAGN_TILT_COMP;
295 	break;
296 	default:
297 		return -EINVAL;
298 	}
299 
300 	iio_val = magn_state->magn_val_addr[offset];
301 
302 	if (iio_val != NULL)
303 		*iio_val = *((u32 *)raw_data);
304 	else
305 		ret = -EINVAL;
306 
307 	return ret;
308 }
309 
310 /* Parse report which is specific to an usage id*/
311 static int magn_3d_parse_report(struct platform_device *pdev,
312 				struct hid_sensor_hub_device *hsdev,
313 				struct iio_chan_spec **channels,
314 				int *chan_count,
315 				unsigned usage_id,
316 				struct magn_3d_state *st)
317 {
318 	int i;
319 	int attr_count = 0;
320 	struct iio_chan_spec *_channels;
321 
322 	/* Scan for each usage attribute supported */
323 	for (i = 0; i < MAGN_3D_CHANNEL_MAX; i++) {
324 		int status;
325 		u32 address = magn_3d_addresses[i];
326 
327 		/* Check if usage attribute exists in the sensor hub device */
328 		status = sensor_hub_input_get_attribute_info(hsdev,
329 			HID_INPUT_REPORT,
330 			usage_id,
331 			address,
332 			&(st->magn[i]));
333 		if (!status)
334 			attr_count++;
335 	}
336 
337 	if (attr_count <= 0) {
338 		dev_err(&pdev->dev,
339 			"failed to find any supported usage attributes in report\n");
340 		return  -EINVAL;
341 	}
342 
343 	dev_dbg(&pdev->dev, "magn_3d Found %d usage attributes\n",
344 			attr_count);
345 	dev_dbg(&pdev->dev, "magn_3d X: %x:%x Y: %x:%x Z: %x:%x\n",
346 			st->magn[0].index,
347 			st->magn[0].report_id,
348 			st->magn[1].index, st->magn[1].report_id,
349 			st->magn[2].index, st->magn[2].report_id);
350 
351 	/* Setup IIO channel array */
352 	_channels = devm_kcalloc(&pdev->dev, attr_count,
353 				sizeof(struct iio_chan_spec),
354 				GFP_KERNEL);
355 	if (!_channels) {
356 		dev_err(&pdev->dev,
357 			"failed to allocate space for iio channels\n");
358 		return -ENOMEM;
359 	}
360 
361 	st->iio_vals = devm_kcalloc(&pdev->dev, attr_count,
362 				sizeof(u32),
363 				GFP_KERNEL);
364 	if (!st->iio_vals) {
365 		dev_err(&pdev->dev,
366 			"failed to allocate space for iio values array\n");
367 		return -ENOMEM;
368 	}
369 
370 	for (i = 0, *chan_count = 0;
371 	i < MAGN_3D_CHANNEL_MAX && *chan_count < attr_count;
372 	i++){
373 		if (st->magn[i].index >= 0) {
374 			/* Setup IIO channel struct */
375 			(_channels[*chan_count]) = magn_3d_channels[i];
376 			(_channels[*chan_count]).scan_index = *chan_count;
377 			(_channels[*chan_count]).address = i;
378 
379 			/* Set magn_val_addr to iio value address */
380 			st->magn_val_addr[i] = &(st->iio_vals[*chan_count]);
381 			magn_3d_adjust_channel_bit_mask(_channels,
382 							*chan_count,
383 							st->magn[i].size);
384 			(*chan_count)++;
385 		}
386 	}
387 
388 	if (*chan_count <= 0) {
389 		dev_err(&pdev->dev,
390 			"failed to find any magnetic channels setup\n");
391 		return -EINVAL;
392 	}
393 
394 	*channels = _channels;
395 
396 	dev_dbg(&pdev->dev, "magn_3d Setup %d IIO channels\n",
397 			*chan_count);
398 
399 	st->scale_precision = hid_sensor_format_scale(
400 				HID_USAGE_SENSOR_COMPASS_3D,
401 				&st->magn[CHANNEL_SCAN_INDEX_X],
402 				&st->scale_pre_decml, &st->scale_post_decml);
403 
404 	/* Set Sensitivity field ids, when there is no individual modifier */
405 	if (st->common_attributes.sensitivity.index < 0) {
406 		sensor_hub_input_get_attribute_info(hsdev,
407 			HID_FEATURE_REPORT, usage_id,
408 			HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS |
409 			HID_USAGE_SENSOR_DATA_ORIENTATION,
410 			&st->common_attributes.sensitivity);
411 		dev_dbg(&pdev->dev, "Sensitivity index:report %d:%d\n",
412 			st->common_attributes.sensitivity.index,
413 			st->common_attributes.sensitivity.report_id);
414 	}
415 
416 	return 0;
417 }
418 
419 /* Function to initialize the processing for usage id */
420 static int hid_magn_3d_probe(struct platform_device *pdev)
421 {
422 	int ret = 0;
423 	static char *name = "magn_3d";
424 	struct iio_dev *indio_dev;
425 	struct magn_3d_state *magn_state;
426 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
427 	struct iio_chan_spec *channels;
428 	int chan_count = 0;
429 
430 	indio_dev = devm_iio_device_alloc(&pdev->dev,
431 					  sizeof(struct magn_3d_state));
432 	if (indio_dev == NULL)
433 		return -ENOMEM;
434 
435 	platform_set_drvdata(pdev, indio_dev);
436 
437 	magn_state = iio_priv(indio_dev);
438 	magn_state->common_attributes.hsdev = hsdev;
439 	magn_state->common_attributes.pdev = pdev;
440 
441 	ret = hid_sensor_parse_common_attributes(hsdev,
442 				HID_USAGE_SENSOR_COMPASS_3D,
443 				&magn_state->common_attributes);
444 	if (ret) {
445 		dev_err(&pdev->dev, "failed to setup common attributes\n");
446 		return ret;
447 	}
448 
449 	ret = magn_3d_parse_report(pdev, hsdev,
450 				&channels, &chan_count,
451 				HID_USAGE_SENSOR_COMPASS_3D, magn_state);
452 	if (ret) {
453 		dev_err(&pdev->dev, "failed to parse report\n");
454 		return ret;
455 	}
456 
457 	indio_dev->channels = channels;
458 	indio_dev->num_channels = chan_count;
459 	indio_dev->dev.parent = &pdev->dev;
460 	indio_dev->info = &magn_3d_info;
461 	indio_dev->name = name;
462 	indio_dev->modes = INDIO_DIRECT_MODE;
463 
464 	ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
465 		NULL, NULL);
466 	if (ret) {
467 		dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
468 		return ret;
469 	}
470 	atomic_set(&magn_state->common_attributes.data_ready, 0);
471 	ret = hid_sensor_setup_trigger(indio_dev, name,
472 					&magn_state->common_attributes);
473 	if (ret < 0) {
474 		dev_err(&pdev->dev, "trigger setup failed\n");
475 		goto error_unreg_buffer_funcs;
476 	}
477 
478 	ret = iio_device_register(indio_dev);
479 	if (ret) {
480 		dev_err(&pdev->dev, "device register failed\n");
481 		goto error_remove_trigger;
482 	}
483 
484 	magn_state->callbacks.send_event = magn_3d_proc_event;
485 	magn_state->callbacks.capture_sample = magn_3d_capture_sample;
486 	magn_state->callbacks.pdev = pdev;
487 	ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_COMPASS_3D,
488 					&magn_state->callbacks);
489 	if (ret < 0) {
490 		dev_err(&pdev->dev, "callback reg failed\n");
491 		goto error_iio_unreg;
492 	}
493 
494 	return ret;
495 
496 error_iio_unreg:
497 	iio_device_unregister(indio_dev);
498 error_remove_trigger:
499 	hid_sensor_remove_trigger(&magn_state->common_attributes);
500 error_unreg_buffer_funcs:
501 	iio_triggered_buffer_cleanup(indio_dev);
502 	return ret;
503 }
504 
505 /* Function to deinitialize the processing for usage id */
506 static int hid_magn_3d_remove(struct platform_device *pdev)
507 {
508 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
509 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
510 	struct magn_3d_state *magn_state = iio_priv(indio_dev);
511 
512 	sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_COMPASS_3D);
513 	iio_device_unregister(indio_dev);
514 	hid_sensor_remove_trigger(&magn_state->common_attributes);
515 	iio_triggered_buffer_cleanup(indio_dev);
516 
517 	return 0;
518 }
519 
520 static struct platform_device_id hid_magn_3d_ids[] = {
521 	{
522 		/* Format: HID-SENSOR-usage_id_in_hex_lowercase */
523 		.name = "HID-SENSOR-200083",
524 	},
525 	{ /* sentinel */ }
526 };
527 MODULE_DEVICE_TABLE(platform, hid_magn_3d_ids);
528 
529 static struct platform_driver hid_magn_3d_platform_driver = {
530 	.id_table = hid_magn_3d_ids,
531 	.driver = {
532 		.name	= KBUILD_MODNAME,
533 	},
534 	.probe		= hid_magn_3d_probe,
535 	.remove		= hid_magn_3d_remove,
536 };
537 module_platform_driver(hid_magn_3d_platform_driver);
538 
539 MODULE_DESCRIPTION("HID Sensor Magnetometer 3D");
540 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@intel.com>");
541 MODULE_LICENSE("GPL");
542