xref: /linux/drivers/iio/light/hid-sensor-prox.c (revision e0bf6c5ca2d3281f231c5f0c9bf145e9513644de)
1 /*
2  * HID Sensors Driver
3  * Copyright (c) 2014, 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.
16  *
17  */
18 #include <linux/device.h>
19 #include <linux/platform_device.h>
20 #include <linux/module.h>
21 #include <linux/interrupt.h>
22 #include <linux/irq.h>
23 #include <linux/slab.h>
24 #include <linux/delay.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-trigger.h"
32 
33 #define CHANNEL_SCAN_INDEX_PRESENCE 0
34 
35 struct prox_state {
36 	struct hid_sensor_hub_callbacks callbacks;
37 	struct hid_sensor_common common_attributes;
38 	struct hid_sensor_hub_attribute_info prox_attr;
39 	u32 human_presence;
40 };
41 
42 /* Channel definitions */
43 static const struct iio_chan_spec prox_channels[] = {
44 	{
45 		.type = IIO_PROXIMITY,
46 		.modified = 1,
47 		.channel2 = IIO_NO_MOD,
48 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
49 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
50 		BIT(IIO_CHAN_INFO_SCALE) |
51 		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
52 		BIT(IIO_CHAN_INFO_HYSTERESIS),
53 		.scan_index = CHANNEL_SCAN_INDEX_PRESENCE,
54 	}
55 };
56 
57 /* Adjust channel real bits based on report descriptor */
58 static void prox_adjust_channel_bit_mask(struct iio_chan_spec *channels,
59 					int channel, int size)
60 {
61 	channels[channel].scan_type.sign = 's';
62 	/* Real storage bits will change based on the report desc. */
63 	channels[channel].scan_type.realbits = size * 8;
64 	/* Maximum size of a sample to capture is u32 */
65 	channels[channel].scan_type.storagebits = sizeof(u32) * 8;
66 }
67 
68 /* Channel read_raw handler */
69 static int prox_read_raw(struct iio_dev *indio_dev,
70 			      struct iio_chan_spec const *chan,
71 			      int *val, int *val2,
72 			      long mask)
73 {
74 	struct prox_state *prox_state = iio_priv(indio_dev);
75 	int report_id = -1;
76 	u32 address;
77 	int ret_type;
78 
79 	*val = 0;
80 	*val2 = 0;
81 	switch (mask) {
82 	case IIO_CHAN_INFO_RAW:
83 		switch (chan->scan_index) {
84 		case  CHANNEL_SCAN_INDEX_PRESENCE:
85 			report_id = prox_state->prox_attr.report_id;
86 			address =
87 			HID_USAGE_SENSOR_HUMAN_PRESENCE;
88 			break;
89 		default:
90 			report_id = -1;
91 			break;
92 		}
93 		if (report_id >= 0) {
94 			hid_sensor_power_state(&prox_state->common_attributes,
95 						true);
96 			*val = sensor_hub_input_attr_get_raw_value(
97 				prox_state->common_attributes.hsdev,
98 				HID_USAGE_SENSOR_PROX, address,
99 				report_id);
100 			hid_sensor_power_state(&prox_state->common_attributes,
101 						false);
102 		} else {
103 			*val = 0;
104 			return -EINVAL;
105 		}
106 		ret_type = IIO_VAL_INT;
107 		break;
108 	case IIO_CHAN_INFO_SCALE:
109 		*val = prox_state->prox_attr.units;
110 		ret_type = IIO_VAL_INT;
111 		break;
112 	case IIO_CHAN_INFO_OFFSET:
113 		*val = hid_sensor_convert_exponent(
114 				prox_state->prox_attr.unit_expo);
115 		ret_type = IIO_VAL_INT;
116 		break;
117 	case IIO_CHAN_INFO_SAMP_FREQ:
118 		ret_type = hid_sensor_read_samp_freq_value(
119 				&prox_state->common_attributes, val, val2);
120 		break;
121 	case IIO_CHAN_INFO_HYSTERESIS:
122 		ret_type = hid_sensor_read_raw_hyst_value(
123 				&prox_state->common_attributes, val, val2);
124 		break;
125 	default:
126 		ret_type = -EINVAL;
127 		break;
128 	}
129 
130 	return ret_type;
131 }
132 
133 /* Channel write_raw handler */
134 static int prox_write_raw(struct iio_dev *indio_dev,
135 			       struct iio_chan_spec const *chan,
136 			       int val,
137 			       int val2,
138 			       long mask)
139 {
140 	struct prox_state *prox_state = iio_priv(indio_dev);
141 	int ret = 0;
142 
143 	switch (mask) {
144 	case IIO_CHAN_INFO_SAMP_FREQ:
145 		ret = hid_sensor_write_samp_freq_value(
146 				&prox_state->common_attributes, val, val2);
147 		break;
148 	case IIO_CHAN_INFO_HYSTERESIS:
149 		ret = hid_sensor_write_raw_hyst_value(
150 				&prox_state->common_attributes, val, val2);
151 		break;
152 	default:
153 		ret = -EINVAL;
154 	}
155 
156 	return ret;
157 }
158 
159 static const struct iio_info prox_info = {
160 	.driver_module = THIS_MODULE,
161 	.read_raw = &prox_read_raw,
162 	.write_raw = &prox_write_raw,
163 };
164 
165 /* Function to push data to buffer */
166 static void hid_sensor_push_data(struct iio_dev *indio_dev, const void *data,
167 					int len)
168 {
169 	dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n");
170 	iio_push_to_buffers(indio_dev, data);
171 }
172 
173 /* Callback handler to send event after all samples are received and captured */
174 static int prox_proc_event(struct hid_sensor_hub_device *hsdev,
175 				unsigned usage_id,
176 				void *priv)
177 {
178 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
179 	struct prox_state *prox_state = iio_priv(indio_dev);
180 
181 	dev_dbg(&indio_dev->dev, "prox_proc_event\n");
182 	if (atomic_read(&prox_state->common_attributes.data_ready))
183 		hid_sensor_push_data(indio_dev,
184 				&prox_state->human_presence,
185 				sizeof(prox_state->human_presence));
186 
187 	return 0;
188 }
189 
190 /* Capture samples in local storage */
191 static int prox_capture_sample(struct hid_sensor_hub_device *hsdev,
192 				unsigned usage_id,
193 				size_t raw_len, char *raw_data,
194 				void *priv)
195 {
196 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
197 	struct prox_state *prox_state = iio_priv(indio_dev);
198 	int ret = -EINVAL;
199 
200 	switch (usage_id) {
201 	case HID_USAGE_SENSOR_HUMAN_PRESENCE:
202 		prox_state->human_presence = *(u32 *)raw_data;
203 		ret = 0;
204 		break;
205 	default:
206 		break;
207 	}
208 
209 	return ret;
210 }
211 
212 /* Parse report which is specific to an usage id*/
213 static int prox_parse_report(struct platform_device *pdev,
214 				struct hid_sensor_hub_device *hsdev,
215 				struct iio_chan_spec *channels,
216 				unsigned usage_id,
217 				struct prox_state *st)
218 {
219 	int ret;
220 
221 	ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
222 			usage_id,
223 			HID_USAGE_SENSOR_HUMAN_PRESENCE,
224 			&st->prox_attr);
225 	if (ret < 0)
226 		return ret;
227 	prox_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_PRESENCE,
228 					st->prox_attr.size);
229 
230 	dev_dbg(&pdev->dev, "prox %x:%x\n", st->prox_attr.index,
231 			st->prox_attr.report_id);
232 
233 	/* Set Sensitivity field ids, when there is no individual modifier */
234 	if (st->common_attributes.sensitivity.index < 0) {
235 		sensor_hub_input_get_attribute_info(hsdev,
236 			HID_FEATURE_REPORT, usage_id,
237 			HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS |
238 			HID_USAGE_SENSOR_DATA_PRESENCE,
239 			&st->common_attributes.sensitivity);
240 		dev_dbg(&pdev->dev, "Sensitivity index:report %d:%d\n",
241 			st->common_attributes.sensitivity.index,
242 			st->common_attributes.sensitivity.report_id);
243 	}
244 	return ret;
245 }
246 
247 /* Function to initialize the processing for usage id */
248 static int hid_prox_probe(struct platform_device *pdev)
249 {
250 	int ret = 0;
251 	static const char *name = "prox";
252 	struct iio_dev *indio_dev;
253 	struct prox_state *prox_state;
254 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
255 	struct iio_chan_spec *channels;
256 
257 	indio_dev = devm_iio_device_alloc(&pdev->dev,
258 				sizeof(struct prox_state));
259 	if (!indio_dev)
260 		return -ENOMEM;
261 	platform_set_drvdata(pdev, indio_dev);
262 
263 	prox_state = iio_priv(indio_dev);
264 	prox_state->common_attributes.hsdev = hsdev;
265 	prox_state->common_attributes.pdev = pdev;
266 
267 	ret = hid_sensor_parse_common_attributes(hsdev, HID_USAGE_SENSOR_PROX,
268 					&prox_state->common_attributes);
269 	if (ret) {
270 		dev_err(&pdev->dev, "failed to setup common attributes\n");
271 		return ret;
272 	}
273 
274 	channels = kmemdup(prox_channels, sizeof(prox_channels), GFP_KERNEL);
275 	if (!channels) {
276 		dev_err(&pdev->dev, "failed to duplicate channels\n");
277 		return -ENOMEM;
278 	}
279 
280 	ret = prox_parse_report(pdev, hsdev, channels,
281 				HID_USAGE_SENSOR_PROX, prox_state);
282 	if (ret) {
283 		dev_err(&pdev->dev, "failed to setup attributes\n");
284 		goto error_free_dev_mem;
285 	}
286 
287 	indio_dev->channels = channels;
288 	indio_dev->num_channels =
289 				ARRAY_SIZE(prox_channels);
290 	indio_dev->dev.parent = &pdev->dev;
291 	indio_dev->info = &prox_info;
292 	indio_dev->name = name;
293 	indio_dev->modes = INDIO_DIRECT_MODE;
294 
295 	ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
296 		NULL, NULL);
297 	if (ret) {
298 		dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
299 		goto error_free_dev_mem;
300 	}
301 	atomic_set(&prox_state->common_attributes.data_ready, 0);
302 	ret = hid_sensor_setup_trigger(indio_dev, name,
303 				&prox_state->common_attributes);
304 	if (ret) {
305 		dev_err(&pdev->dev, "trigger setup failed\n");
306 		goto error_unreg_buffer_funcs;
307 	}
308 
309 	ret = iio_device_register(indio_dev);
310 	if (ret) {
311 		dev_err(&pdev->dev, "device register failed\n");
312 		goto error_remove_trigger;
313 	}
314 
315 	prox_state->callbacks.send_event = prox_proc_event;
316 	prox_state->callbacks.capture_sample = prox_capture_sample;
317 	prox_state->callbacks.pdev = pdev;
318 	ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_PROX,
319 					&prox_state->callbacks);
320 	if (ret < 0) {
321 		dev_err(&pdev->dev, "callback reg failed\n");
322 		goto error_iio_unreg;
323 	}
324 
325 	return ret;
326 
327 error_iio_unreg:
328 	iio_device_unregister(indio_dev);
329 error_remove_trigger:
330 	hid_sensor_remove_trigger(&prox_state->common_attributes);
331 error_unreg_buffer_funcs:
332 	iio_triggered_buffer_cleanup(indio_dev);
333 error_free_dev_mem:
334 	kfree(indio_dev->channels);
335 	return ret;
336 }
337 
338 /* Function to deinitialize the processing for usage id */
339 static int hid_prox_remove(struct platform_device *pdev)
340 {
341 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
342 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
343 	struct prox_state *prox_state = iio_priv(indio_dev);
344 
345 	sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_PROX);
346 	iio_device_unregister(indio_dev);
347 	hid_sensor_remove_trigger(&prox_state->common_attributes);
348 	iio_triggered_buffer_cleanup(indio_dev);
349 	kfree(indio_dev->channels);
350 
351 	return 0;
352 }
353 
354 static struct platform_device_id hid_prox_ids[] = {
355 	{
356 		/* Format: HID-SENSOR-usage_id_in_hex_lowercase */
357 		.name = "HID-SENSOR-200011",
358 	},
359 	{ /* sentinel */ }
360 };
361 MODULE_DEVICE_TABLE(platform, hid_prox_ids);
362 
363 static struct platform_driver hid_prox_platform_driver = {
364 	.id_table = hid_prox_ids,
365 	.driver = {
366 		.name	= KBUILD_MODNAME,
367 		.pm	= &hid_sensor_pm_ops,
368 	},
369 	.probe		= hid_prox_probe,
370 	.remove		= hid_prox_remove,
371 };
372 module_platform_driver(hid_prox_platform_driver);
373 
374 MODULE_DESCRIPTION("HID Sensor Proximity");
375 MODULE_AUTHOR("Archana Patni <archana.patni@intel.com>");
376 MODULE_LICENSE("GPL");
377