free electrons

Embedded Linux Experts

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
/*
 * HID Sensors Driver
 * Copyright (c) 2012, Intel Corporation.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
 *
 */
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/hid-sensor-hub.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/iio/buffer.h>
#include <linux/iio/trigger_consumer.h>
#include <linux/iio/triggered_buffer.h>
#include "../common/hid-sensors/hid-sensor-trigger.h"

enum {
	CHANNEL_SCAN_INDEX_INTENSITY = 0,
	CHANNEL_SCAN_INDEX_ILLUM = 1,
	CHANNEL_SCAN_INDEX_MAX
};

struct als_state {
	struct hid_sensor_hub_callbacks callbacks;
	struct hid_sensor_common common_attributes;
	struct hid_sensor_hub_attribute_info als_illum;
	u32 illum[CHANNEL_SCAN_INDEX_MAX];
	int scale_pre_decml;
	int scale_post_decml;
	int scale_precision;
	int value_offset;
};

/* Channel definitions */
static const struct iio_chan_spec als_channels[] = {
	{
		.type = IIO_INTENSITY,
		.modified = 1,
		.channel2 = IIO_MOD_LIGHT_BOTH,
		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
		BIT(IIO_CHAN_INFO_SCALE) |
		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
		BIT(IIO_CHAN_INFO_HYSTERESIS),
		.scan_index = CHANNEL_SCAN_INDEX_INTENSITY,
	},
	{
		.type = IIO_LIGHT,
		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
		BIT(IIO_CHAN_INFO_SCALE) |
		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
		BIT(IIO_CHAN_INFO_HYSTERESIS),
		.scan_index = CHANNEL_SCAN_INDEX_ILLUM,
	}
};

/* Adjust channel real bits based on report descriptor */
static void als_adjust_channel_bit_mask(struct iio_chan_spec *channels,
					int channel, int size)
{
	channels[channel].scan_type.sign = 's';
	/* Real storage bits will change based on the report desc. */
	channels[channel].scan_type.realbits = size * 8;
	/* Maximum size of a sample to capture is u32 */
	channels[channel].scan_type.storagebits = sizeof(u32) * 8;
}

/* Channel read_raw handler */
static int als_read_raw(struct iio_dev *indio_dev,
			      struct iio_chan_spec const *chan,
			      int *val, int *val2,
			      long mask)
{
	struct als_state *als_state = iio_priv(indio_dev);
	int report_id = -1;
	u32 address;
	int ret_type;

	*val = 0;
	*val2 = 0;
	switch (mask) {
	case 0:
		switch (chan->scan_index) {
		case  CHANNEL_SCAN_INDEX_INTENSITY:
		case  CHANNEL_SCAN_INDEX_ILLUM:
			report_id = als_state->als_illum.report_id;
			address =
			HID_USAGE_SENSOR_LIGHT_ILLUM;
			break;
		default:
			report_id = -1;
			break;
		}
		if (report_id >= 0) {
			hid_sensor_power_state(&als_state->common_attributes,
						true);
			*val = sensor_hub_input_attr_get_raw_value(
					als_state->common_attributes.hsdev,
					HID_USAGE_SENSOR_ALS, address,
					report_id,
					SENSOR_HUB_SYNC);
			hid_sensor_power_state(&als_state->common_attributes,
						false);
		} else {
			*val = 0;
			return -EINVAL;
		}
		ret_type = IIO_VAL_INT;
		break;
	case IIO_CHAN_INFO_SCALE:
		*val = als_state->scale_pre_decml;
		*val2 = als_state->scale_post_decml;
		ret_type = als_state->scale_precision;
		break;
	case IIO_CHAN_INFO_OFFSET:
		*val = als_state->value_offset;
		ret_type = IIO_VAL_INT;
		break;
	case IIO_CHAN_INFO_SAMP_FREQ:
		ret_type = hid_sensor_read_samp_freq_value(
				&als_state->common_attributes, val, val2);
		break;
	case IIO_CHAN_INFO_HYSTERESIS:
		ret_type = hid_sensor_read_raw_hyst_value(
				&als_state->common_attributes, val, val2);
		break;
	default:
		ret_type = -EINVAL;
		break;
	}

	return ret_type;
}

/* Channel write_raw handler */
static int als_write_raw(struct iio_dev *indio_dev,
			       struct iio_chan_spec const *chan,
			       int val,
			       int val2,
			       long mask)
{
	struct als_state *als_state = iio_priv(indio_dev);
	int ret = 0;

	switch (mask) {
	case IIO_CHAN_INFO_SAMP_FREQ:
		ret = hid_sensor_write_samp_freq_value(
				&als_state->common_attributes, val, val2);
		break;
	case IIO_CHAN_INFO_HYSTERESIS:
		ret = hid_sensor_write_raw_hyst_value(
				&als_state->common_attributes, val, val2);
		break;
	default:
		ret = -EINVAL;
	}

	return ret;
}

static const struct iio_info als_info = {
	.driver_module = THIS_MODULE,
	.read_raw = &als_read_raw,
	.write_raw = &als_write_raw,
};

/* Function to push data to buffer */
static void hid_sensor_push_data(struct iio_dev *indio_dev, const void *data,
					int len)
{
	dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n");
	iio_push_to_buffers(indio_dev, data);
}

/* Callback handler to send event after all samples are received and captured */
static int als_proc_event(struct hid_sensor_hub_device *hsdev,
				unsigned usage_id,
				void *priv)
{
	struct iio_dev *indio_dev = platform_get_drvdata(priv);
	struct als_state *als_state = iio_priv(indio_dev);

	dev_dbg(&indio_dev->dev, "als_proc_event\n");
	if (atomic_read(&als_state->common_attributes.data_ready))
		hid_sensor_push_data(indio_dev,
				&als_state->illum,
				sizeof(als_state->illum));

	return 0;
}

/* Capture samples in local storage */
static int als_capture_sample(struct hid_sensor_hub_device *hsdev,
				unsigned usage_id,
				size_t raw_len, char *raw_data,
				void *priv)
{
	struct iio_dev *indio_dev = platform_get_drvdata(priv);
	struct als_state *als_state = iio_priv(indio_dev);
	int ret = -EINVAL;
	u32 sample_data = *(u32 *)raw_data;

	switch (usage_id) {
	case HID_USAGE_SENSOR_LIGHT_ILLUM:
		als_state->illum[CHANNEL_SCAN_INDEX_INTENSITY] = sample_data;
		als_state->illum[CHANNEL_SCAN_INDEX_ILLUM] = sample_data;
		ret = 0;
		break;
	default:
		break;
	}

	return ret;
}

/* Parse report which is specific to an usage id*/
static int als_parse_report(struct platform_device *pdev,
				struct hid_sensor_hub_device *hsdev,
				struct iio_chan_spec *channels,
				unsigned usage_id,
				struct als_state *st)
{
	int ret;

	ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
			usage_id,
			HID_USAGE_SENSOR_LIGHT_ILLUM,
			&st->als_illum);
	if (ret < 0)
		return ret;
	als_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_INTENSITY,
				    st->als_illum.size);
	als_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_ILLUM,
					st->als_illum.size);

	dev_dbg(&pdev->dev, "als %x:%x\n", st->als_illum.index,
			st->als_illum.report_id);

	st->scale_precision = hid_sensor_format_scale(
				HID_USAGE_SENSOR_ALS,
				&st->als_illum,
				&st->scale_pre_decml, &st->scale_post_decml);

	/* Set Sensitivity field ids, when there is no individual modifier */
	if (st->common_attributes.sensitivity.index < 0) {
		sensor_hub_input_get_attribute_info(hsdev,
			HID_FEATURE_REPORT, usage_id,
			HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS |
			HID_USAGE_SENSOR_DATA_LIGHT,
			&st->common_attributes.sensitivity);
		dev_dbg(&pdev->dev, "Sensitivity index:report %d:%d\n",
			st->common_attributes.sensitivity.index,
			st->common_attributes.sensitivity.report_id);
	}
	return ret;
}

/* Function to initialize the processing for usage id */
static int hid_als_probe(struct platform_device *pdev)
{
	int ret = 0;
	static const char *name = "als";
	struct iio_dev *indio_dev;
	struct als_state *als_state;
	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;

	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(struct als_state));
	if (!indio_dev)
		return -ENOMEM;
	platform_set_drvdata(pdev, indio_dev);

	als_state = iio_priv(indio_dev);
	als_state->common_attributes.hsdev = hsdev;
	als_state->common_attributes.pdev = pdev;

	ret = hid_sensor_parse_common_attributes(hsdev, HID_USAGE_SENSOR_ALS,
					&als_state->common_attributes);
	if (ret) {
		dev_err(&pdev->dev, "failed to setup common attributes\n");
		return ret;
	}

	indio_dev->channels = kmemdup(als_channels,
				      sizeof(als_channels), GFP_KERNEL);
	if (!indio_dev->channels) {
		dev_err(&pdev->dev, "failed to duplicate channels\n");
		return -ENOMEM;
	}

	ret = als_parse_report(pdev, hsdev,
			       (struct iio_chan_spec *)indio_dev->channels,
			       HID_USAGE_SENSOR_ALS, als_state);
	if (ret) {
		dev_err(&pdev->dev, "failed to setup attributes\n");
		goto error_free_dev_mem;
	}

	indio_dev->num_channels =
				ARRAY_SIZE(als_channels);
	indio_dev->dev.parent = &pdev->dev;
	indio_dev->info = &als_info;
	indio_dev->name = name;
	indio_dev->modes = INDIO_DIRECT_MODE;

	ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
		NULL, NULL);
	if (ret) {
		dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
		goto error_free_dev_mem;
	}
	atomic_set(&als_state->common_attributes.data_ready, 0);
	ret = hid_sensor_setup_trigger(indio_dev, name,
				&als_state->common_attributes);
	if (ret < 0) {
		dev_err(&pdev->dev, "trigger setup failed\n");
		goto error_unreg_buffer_funcs;
	}

	ret = iio_device_register(indio_dev);
	if (ret) {
		dev_err(&pdev->dev, "device register failed\n");
		goto error_remove_trigger;
	}

	als_state->callbacks.send_event = als_proc_event;
	als_state->callbacks.capture_sample = als_capture_sample;
	als_state->callbacks.pdev = pdev;
	ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_ALS,
					&als_state->callbacks);
	if (ret < 0) {
		dev_err(&pdev->dev, "callback reg failed\n");
		goto error_iio_unreg;
	}

	return ret;

error_iio_unreg:
	iio_device_unregister(indio_dev);
error_remove_trigger:
	hid_sensor_remove_trigger(&als_state->common_attributes);
error_unreg_buffer_funcs:
	iio_triggered_buffer_cleanup(indio_dev);
error_free_dev_mem:
	kfree(indio_dev->channels);
	return ret;
}

/* Function to deinitialize the processing for usage id */
static int hid_als_remove(struct platform_device *pdev)
{
	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
	struct als_state *als_state = iio_priv(indio_dev);

	sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_ALS);
	iio_device_unregister(indio_dev);
	hid_sensor_remove_trigger(&als_state->common_attributes);
	iio_triggered_buffer_cleanup(indio_dev);
	kfree(indio_dev->channels);

	return 0;
}

static const struct platform_device_id hid_als_ids[] = {
	{
		/* Format: HID-SENSOR-usage_id_in_hex_lowercase */
		.name = "HID-SENSOR-200041",
	},
	{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(platform, hid_als_ids);

static struct platform_driver hid_als_platform_driver = {
	.id_table = hid_als_ids,
	.driver = {
		.name	= KBUILD_MODNAME,
		.pm	= &hid_sensor_pm_ops,
	},
	.probe		= hid_als_probe,
	.remove		= hid_als_remove,
};
module_platform_driver(hid_als_platform_driver);

MODULE_DESCRIPTION("HID Sensor ALS");
MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@intel.com>");
MODULE_LICENSE("GPL");