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 {
35 	CHANNEL_SCAN_INDEX_INTENSITY = 0,
36 	CHANNEL_SCAN_INDEX_ILLUM = 1,
37 	CHANNEL_SCAN_INDEX_MAX
38 };
39 
40 struct als_state {
41 	struct hid_sensor_hub_callbacks callbacks;
42 	struct hid_sensor_common common_attributes;
43 	struct hid_sensor_hub_attribute_info als_illum;
44 	u32 illum[CHANNEL_SCAN_INDEX_MAX];
45 	int scale_pre_decml;
46 	int scale_post_decml;
47 	int scale_precision;
48 	int value_offset;
49 };
50 
51 /* Channel definitions */
52 static const struct iio_chan_spec als_channels[] = {
53 	{
54 		.type = IIO_INTENSITY,
55 		.modified = 1,
56 		.channel2 = IIO_MOD_LIGHT_BOTH,
57 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
58 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
59 		BIT(IIO_CHAN_INFO_SCALE) |
60 		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
61 		BIT(IIO_CHAN_INFO_HYSTERESIS),
62 		.scan_index = CHANNEL_SCAN_INDEX_INTENSITY,
63 	},
64 	{
65 		.type = IIO_LIGHT,
66 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
67 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
68 		BIT(IIO_CHAN_INFO_SCALE) |
69 		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
70 		BIT(IIO_CHAN_INFO_HYSTERESIS),
71 		.scan_index = CHANNEL_SCAN_INDEX_ILLUM,
72 	}
73 };
74 
75 /* Adjust channel real bits based on report descriptor */
76 static void als_adjust_channel_bit_mask(struct iio_chan_spec *channels,
77 					int channel, int size)
78 {
79 	channels[channel].scan_type.sign = 's';
80 	/* Real storage bits will change based on the report desc. */
81 	channels[channel].scan_type.realbits = size * 8;
82 	/* Maximum size of a sample to capture is u32 */
83 	channels[channel].scan_type.storagebits = sizeof(u32) * 8;
84 }
85 
86 /* Channel read_raw handler */
87 static int als_read_raw(struct iio_dev *indio_dev,
88 			      struct iio_chan_spec const *chan,
89 			      int *val, int *val2,
90 			      long mask)
91 {
92 	struct als_state *als_state = iio_priv(indio_dev);
93 	int report_id = -1;
94 	u32 address;
95 	int ret_type;
96 
97 	*val = 0;
98 	*val2 = 0;
99 	switch (mask) {
100 	case 0:
101 		switch (chan->scan_index) {
102 		case  CHANNEL_SCAN_INDEX_INTENSITY:
103 		case  CHANNEL_SCAN_INDEX_ILLUM:
104 			report_id = als_state->als_illum.report_id;
105 			address =
106 			HID_USAGE_SENSOR_LIGHT_ILLUM;
107 			break;
108 		default:
109 			report_id = -1;
110 			break;
111 		}
112 		if (report_id >= 0) {
113 			hid_sensor_power_state(&als_state->common_attributes,
114 						true);
115 			*val = sensor_hub_input_attr_get_raw_value(
116 					als_state->common_attributes.hsdev,
117 					HID_USAGE_SENSOR_ALS, address,
118 					report_id,
119 					SENSOR_HUB_SYNC);
120 			hid_sensor_power_state(&als_state->common_attributes,
121 						false);
122 		} else {
123 			*val = 0;
124 			return -EINVAL;
125 		}
126 		ret_type = IIO_VAL_INT;
127 		break;
128 	case IIO_CHAN_INFO_SCALE:
129 		*val = als_state->scale_pre_decml;
130 		*val2 = als_state->scale_post_decml;
131 		ret_type = als_state->scale_precision;
132 		break;
133 	case IIO_CHAN_INFO_OFFSET:
134 		*val = als_state->value_offset;
135 		ret_type = IIO_VAL_INT;
136 		break;
137 	case IIO_CHAN_INFO_SAMP_FREQ:
138 		ret_type = hid_sensor_read_samp_freq_value(
139 				&als_state->common_attributes, val, val2);
140 		break;
141 	case IIO_CHAN_INFO_HYSTERESIS:
142 		ret_type = hid_sensor_read_raw_hyst_value(
143 				&als_state->common_attributes, val, val2);
144 		break;
145 	default:
146 		ret_type = -EINVAL;
147 		break;
148 	}
149 
150 	return ret_type;
151 }
152 
153 /* Channel write_raw handler */
154 static int als_write_raw(struct iio_dev *indio_dev,
155 			       struct iio_chan_spec const *chan,
156 			       int val,
157 			       int val2,
158 			       long mask)
159 {
160 	struct als_state *als_state = iio_priv(indio_dev);
161 	int ret = 0;
162 
163 	switch (mask) {
164 	case IIO_CHAN_INFO_SAMP_FREQ:
165 		ret = hid_sensor_write_samp_freq_value(
166 				&als_state->common_attributes, val, val2);
167 		break;
168 	case IIO_CHAN_INFO_HYSTERESIS:
169 		ret = hid_sensor_write_raw_hyst_value(
170 				&als_state->common_attributes, val, val2);
171 		break;
172 	default:
173 		ret = -EINVAL;
174 	}
175 
176 	return ret;
177 }
178 
179 static const struct iio_info als_info = {
180 	.read_raw = &als_read_raw,
181 	.write_raw = &als_write_raw,
182 };
183 
184 /* Function to push data to buffer */
185 static void hid_sensor_push_data(struct iio_dev *indio_dev, const void *data,
186 					int len)
187 {
188 	dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n");
189 	iio_push_to_buffers(indio_dev, data);
190 }
191 
192 /* Callback handler to send event after all samples are received and captured */
193 static int als_proc_event(struct hid_sensor_hub_device *hsdev,
194 				unsigned usage_id,
195 				void *priv)
196 {
197 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
198 	struct als_state *als_state = iio_priv(indio_dev);
199 
200 	dev_dbg(&indio_dev->dev, "als_proc_event\n");
201 	if (atomic_read(&als_state->common_attributes.data_ready))
202 		hid_sensor_push_data(indio_dev,
203 				&als_state->illum,
204 				sizeof(als_state->illum));
205 
206 	return 0;
207 }
208 
209 /* Capture samples in local storage */
210 static int als_capture_sample(struct hid_sensor_hub_device *hsdev,
211 				unsigned usage_id,
212 				size_t raw_len, char *raw_data,
213 				void *priv)
214 {
215 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
216 	struct als_state *als_state = iio_priv(indio_dev);
217 	int ret = -EINVAL;
218 	u32 sample_data = *(u32 *)raw_data;
219 
220 	switch (usage_id) {
221 	case HID_USAGE_SENSOR_LIGHT_ILLUM:
222 		als_state->illum[CHANNEL_SCAN_INDEX_INTENSITY] = sample_data;
223 		als_state->illum[CHANNEL_SCAN_INDEX_ILLUM] = sample_data;
224 		ret = 0;
225 		break;
226 	default:
227 		break;
228 	}
229 
230 	return ret;
231 }
232 
233 /* Parse report which is specific to an usage id*/
234 static int als_parse_report(struct platform_device *pdev,
235 				struct hid_sensor_hub_device *hsdev,
236 				struct iio_chan_spec *channels,
237 				unsigned usage_id,
238 				struct als_state *st)
239 {
240 	int ret;
241 
242 	ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
243 			usage_id,
244 			HID_USAGE_SENSOR_LIGHT_ILLUM,
245 			&st->als_illum);
246 	if (ret < 0)
247 		return ret;
248 	als_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_INTENSITY,
249 				    st->als_illum.size);
250 	als_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_ILLUM,
251 					st->als_illum.size);
252 
253 	dev_dbg(&pdev->dev, "als %x:%x\n", st->als_illum.index,
254 			st->als_illum.report_id);
255 
256 	st->scale_precision = hid_sensor_format_scale(
257 				HID_USAGE_SENSOR_ALS,
258 				&st->als_illum,
259 				&st->scale_pre_decml, &st->scale_post_decml);
260 
261 	/* Set Sensitivity field ids, when there is no individual modifier */
262 	if (st->common_attributes.sensitivity.index < 0) {
263 		sensor_hub_input_get_attribute_info(hsdev,
264 			HID_FEATURE_REPORT, usage_id,
265 			HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS |
266 			HID_USAGE_SENSOR_DATA_LIGHT,
267 			&st->common_attributes.sensitivity);
268 		dev_dbg(&pdev->dev, "Sensitivity index:report %d:%d\n",
269 			st->common_attributes.sensitivity.index,
270 			st->common_attributes.sensitivity.report_id);
271 	}
272 	return ret;
273 }
274 
275 /* Function to initialize the processing for usage id */
276 static int hid_als_probe(struct platform_device *pdev)
277 {
278 	int ret = 0;
279 	static const char *name = "als";
280 	struct iio_dev *indio_dev;
281 	struct als_state *als_state;
282 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
283 
284 	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(struct als_state));
285 	if (!indio_dev)
286 		return -ENOMEM;
287 	platform_set_drvdata(pdev, indio_dev);
288 
289 	als_state = iio_priv(indio_dev);
290 	als_state->common_attributes.hsdev = hsdev;
291 	als_state->common_attributes.pdev = pdev;
292 
293 	ret = hid_sensor_parse_common_attributes(hsdev, HID_USAGE_SENSOR_ALS,
294 					&als_state->common_attributes);
295 	if (ret) {
296 		dev_err(&pdev->dev, "failed to setup common attributes\n");
297 		return ret;
298 	}
299 
300 	indio_dev->channels = kmemdup(als_channels,
301 				      sizeof(als_channels), GFP_KERNEL);
302 	if (!indio_dev->channels) {
303 		dev_err(&pdev->dev, "failed to duplicate channels\n");
304 		return -ENOMEM;
305 	}
306 
307 	ret = als_parse_report(pdev, hsdev,
308 			       (struct iio_chan_spec *)indio_dev->channels,
309 			       HID_USAGE_SENSOR_ALS, als_state);
310 	if (ret) {
311 		dev_err(&pdev->dev, "failed to setup attributes\n");
312 		goto error_free_dev_mem;
313 	}
314 
315 	indio_dev->num_channels =
316 				ARRAY_SIZE(als_channels);
317 	indio_dev->dev.parent = &pdev->dev;
318 	indio_dev->info = &als_info;
319 	indio_dev->name = name;
320 	indio_dev->modes = INDIO_DIRECT_MODE;
321 
322 	ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
323 		NULL, NULL);
324 	if (ret) {
325 		dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
326 		goto error_free_dev_mem;
327 	}
328 	atomic_set(&als_state->common_attributes.data_ready, 0);
329 	ret = hid_sensor_setup_trigger(indio_dev, name,
330 				&als_state->common_attributes);
331 	if (ret < 0) {
332 		dev_err(&pdev->dev, "trigger setup failed\n");
333 		goto error_unreg_buffer_funcs;
334 	}
335 
336 	ret = iio_device_register(indio_dev);
337 	if (ret) {
338 		dev_err(&pdev->dev, "device register failed\n");
339 		goto error_remove_trigger;
340 	}
341 
342 	als_state->callbacks.send_event = als_proc_event;
343 	als_state->callbacks.capture_sample = als_capture_sample;
344 	als_state->callbacks.pdev = pdev;
345 	ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_ALS,
346 					&als_state->callbacks);
347 	if (ret < 0) {
348 		dev_err(&pdev->dev, "callback reg failed\n");
349 		goto error_iio_unreg;
350 	}
351 
352 	return ret;
353 
354 error_iio_unreg:
355 	iio_device_unregister(indio_dev);
356 error_remove_trigger:
357 	hid_sensor_remove_trigger(&als_state->common_attributes);
358 error_unreg_buffer_funcs:
359 	iio_triggered_buffer_cleanup(indio_dev);
360 error_free_dev_mem:
361 	kfree(indio_dev->channels);
362 	return ret;
363 }
364 
365 /* Function to deinitialize the processing for usage id */
366 static int hid_als_remove(struct platform_device *pdev)
367 {
368 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
369 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
370 	struct als_state *als_state = iio_priv(indio_dev);
371 
372 	sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_ALS);
373 	iio_device_unregister(indio_dev);
374 	hid_sensor_remove_trigger(&als_state->common_attributes);
375 	iio_triggered_buffer_cleanup(indio_dev);
376 	kfree(indio_dev->channels);
377 
378 	return 0;
379 }
380 
381 static const struct platform_device_id hid_als_ids[] = {
382 	{
383 		/* Format: HID-SENSOR-usage_id_in_hex_lowercase */
384 		.name = "HID-SENSOR-200041",
385 	},
386 	{ /* sentinel */ }
387 };
388 MODULE_DEVICE_TABLE(platform, hid_als_ids);
389 
390 static struct platform_driver hid_als_platform_driver = {
391 	.id_table = hid_als_ids,
392 	.driver = {
393 		.name	= KBUILD_MODNAME,
394 		.pm	= &hid_sensor_pm_ops,
395 	},
396 	.probe		= hid_als_probe,
397 	.remove		= hid_als_remove,
398 };
399 module_platform_driver(hid_als_platform_driver);
400 
401 MODULE_DESCRIPTION("HID Sensor ALS");
402 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@intel.com>");
403 MODULE_LICENSE("GPL");
404