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;
78 	int ret_type;
79 	s32 poll_value;
80 
81 	*val = 0;
82 	*val2 = 0;
83 	switch (mask) {
84 	case IIO_CHAN_INFO_RAW:
85 		switch (chan->scan_index) {
86 		case  CHANNEL_SCAN_INDEX_PRESENCE:
87 			report_id = prox_state->prox_attr.report_id;
88 			address =
89 			HID_USAGE_SENSOR_HUMAN_PRESENCE;
90 			break;
91 		default:
92 			report_id = -1;
93 			break;
94 		}
95 		if (report_id >= 0) {
96 			poll_value = hid_sensor_read_poll_value(
97 					&prox_state->common_attributes);
98 			if (poll_value < 0)
99 				return -EINVAL;
100 
101 			hid_sensor_power_state(&prox_state->common_attributes,
102 						true);
103 
104 			msleep_interruptible(poll_value * 2);
105 
106 			*val = sensor_hub_input_attr_get_raw_value(
107 				prox_state->common_attributes.hsdev,
108 				HID_USAGE_SENSOR_PROX, address,
109 				report_id);
110 			hid_sensor_power_state(&prox_state->common_attributes,
111 						false);
112 		} else {
113 			*val = 0;
114 			return -EINVAL;
115 		}
116 		ret_type = IIO_VAL_INT;
117 		break;
118 	case IIO_CHAN_INFO_SCALE:
119 		*val = prox_state->prox_attr.units;
120 		ret_type = IIO_VAL_INT;
121 		break;
122 	case IIO_CHAN_INFO_OFFSET:
123 		*val = hid_sensor_convert_exponent(
124 				prox_state->prox_attr.unit_expo);
125 		ret_type = IIO_VAL_INT;
126 		break;
127 	case IIO_CHAN_INFO_SAMP_FREQ:
128 		ret = hid_sensor_read_samp_freq_value(
129 				&prox_state->common_attributes, val, val2);
130 		ret_type = IIO_VAL_INT_PLUS_MICRO;
131 		break;
132 	case IIO_CHAN_INFO_HYSTERESIS:
133 		ret = hid_sensor_read_raw_hyst_value(
134 				&prox_state->common_attributes, val, val2);
135 		ret_type = IIO_VAL_INT_PLUS_MICRO;
136 		break;
137 	default:
138 		ret_type = -EINVAL;
139 		break;
140 	}
141 
142 	return ret_type;
143 }
144 
145 /* Channel write_raw handler */
146 static int prox_write_raw(struct iio_dev *indio_dev,
147 			       struct iio_chan_spec const *chan,
148 			       int val,
149 			       int val2,
150 			       long mask)
151 {
152 	struct prox_state *prox_state = iio_priv(indio_dev);
153 	int ret = 0;
154 
155 	switch (mask) {
156 	case IIO_CHAN_INFO_SAMP_FREQ:
157 		ret = hid_sensor_write_samp_freq_value(
158 				&prox_state->common_attributes, val, val2);
159 		break;
160 	case IIO_CHAN_INFO_HYSTERESIS:
161 		ret = hid_sensor_write_raw_hyst_value(
162 				&prox_state->common_attributes, val, val2);
163 		break;
164 	default:
165 		ret = -EINVAL;
166 	}
167 
168 	return ret;
169 }
170 
171 static const struct iio_info prox_info = {
172 	.driver_module = THIS_MODULE,
173 	.read_raw = &prox_read_raw,
174 	.write_raw = &prox_write_raw,
175 };
176 
177 /* Function to push data to buffer */
178 static void hid_sensor_push_data(struct iio_dev *indio_dev, const void *data,
179 					int len)
180 {
181 	dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n");
182 	iio_push_to_buffers(indio_dev, data);
183 }
184 
185 /* Callback handler to send event after all samples are received and captured */
186 static int prox_proc_event(struct hid_sensor_hub_device *hsdev,
187 				unsigned usage_id,
188 				void *priv)
189 {
190 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
191 	struct prox_state *prox_state = iio_priv(indio_dev);
192 
193 	dev_dbg(&indio_dev->dev, "prox_proc_event\n");
194 	if (atomic_read(&prox_state->common_attributes.data_ready))
195 		hid_sensor_push_data(indio_dev,
196 				&prox_state->human_presence,
197 				sizeof(prox_state->human_presence));
198 
199 	return 0;
200 }
201 
202 /* Capture samples in local storage */
203 static int prox_capture_sample(struct hid_sensor_hub_device *hsdev,
204 				unsigned usage_id,
205 				size_t raw_len, char *raw_data,
206 				void *priv)
207 {
208 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
209 	struct prox_state *prox_state = iio_priv(indio_dev);
210 	int ret = -EINVAL;
211 
212 	switch (usage_id) {
213 	case HID_USAGE_SENSOR_HUMAN_PRESENCE:
214 		prox_state->human_presence = *(u32 *)raw_data;
215 		ret = 0;
216 		break;
217 	default:
218 		break;
219 	}
220 
221 	return ret;
222 }
223 
224 /* Parse report which is specific to an usage id*/
225 static int prox_parse_report(struct platform_device *pdev,
226 				struct hid_sensor_hub_device *hsdev,
227 				struct iio_chan_spec *channels,
228 				unsigned usage_id,
229 				struct prox_state *st)
230 {
231 	int ret;
232 
233 	ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
234 			usage_id,
235 			HID_USAGE_SENSOR_HUMAN_PRESENCE,
236 			&st->prox_attr);
237 	if (ret < 0)
238 		return ret;
239 	prox_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_PRESENCE,
240 					st->prox_attr.size);
241 
242 	dev_dbg(&pdev->dev, "prox %x:%x\n", st->prox_attr.index,
243 			st->prox_attr.report_id);
244 
245 	/* Set Sensitivity field ids, when there is no individual modifier */
246 	if (st->common_attributes.sensitivity.index < 0) {
247 		sensor_hub_input_get_attribute_info(hsdev,
248 			HID_FEATURE_REPORT, usage_id,
249 			HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS |
250 			HID_USAGE_SENSOR_DATA_PRESENCE,
251 			&st->common_attributes.sensitivity);
252 		dev_dbg(&pdev->dev, "Sensitivity index:report %d:%d\n",
253 			st->common_attributes.sensitivity.index,
254 			st->common_attributes.sensitivity.report_id);
255 	}
256 	return ret;
257 }
258 
259 /* Function to initialize the processing for usage id */
260 static int hid_prox_probe(struct platform_device *pdev)
261 {
262 	int ret = 0;
263 	static const char *name = "prox";
264 	struct iio_dev *indio_dev;
265 	struct prox_state *prox_state;
266 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
267 	struct iio_chan_spec *channels;
268 
269 	indio_dev = devm_iio_device_alloc(&pdev->dev,
270 				sizeof(struct prox_state));
271 	if (!indio_dev)
272 		return -ENOMEM;
273 	platform_set_drvdata(pdev, indio_dev);
274 
275 	prox_state = iio_priv(indio_dev);
276 	prox_state->common_attributes.hsdev = hsdev;
277 	prox_state->common_attributes.pdev = pdev;
278 
279 	ret = hid_sensor_parse_common_attributes(hsdev, HID_USAGE_SENSOR_PROX,
280 					&prox_state->common_attributes);
281 	if (ret) {
282 		dev_err(&pdev->dev, "failed to setup common attributes\n");
283 		return ret;
284 	}
285 
286 	channels = kmemdup(prox_channels, sizeof(prox_channels), GFP_KERNEL);
287 	if (!channels) {
288 		dev_err(&pdev->dev, "failed to duplicate channels\n");
289 		return -ENOMEM;
290 	}
291 
292 	ret = prox_parse_report(pdev, hsdev, channels,
293 				HID_USAGE_SENSOR_PROX, prox_state);
294 	if (ret) {
295 		dev_err(&pdev->dev, "failed to setup attributes\n");
296 		goto error_free_dev_mem;
297 	}
298 
299 	indio_dev->channels = channels;
300 	indio_dev->num_channels =
301 				ARRAY_SIZE(prox_channels);
302 	indio_dev->dev.parent = &pdev->dev;
303 	indio_dev->info = &prox_info;
304 	indio_dev->name = name;
305 	indio_dev->modes = INDIO_DIRECT_MODE;
306 
307 	ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
308 		NULL, NULL);
309 	if (ret) {
310 		dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
311 		goto error_free_dev_mem;
312 	}
313 	atomic_set(&prox_state->common_attributes.data_ready, 0);
314 	ret = hid_sensor_setup_trigger(indio_dev, name,
315 				&prox_state->common_attributes);
316 	if (ret) {
317 		dev_err(&pdev->dev, "trigger setup failed\n");
318 		goto error_unreg_buffer_funcs;
319 	}
320 
321 	ret = iio_device_register(indio_dev);
322 	if (ret) {
323 		dev_err(&pdev->dev, "device register failed\n");
324 		goto error_remove_trigger;
325 	}
326 
327 	prox_state->callbacks.send_event = prox_proc_event;
328 	prox_state->callbacks.capture_sample = prox_capture_sample;
329 	prox_state->callbacks.pdev = pdev;
330 	ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_PROX,
331 					&prox_state->callbacks);
332 	if (ret < 0) {
333 		dev_err(&pdev->dev, "callback reg failed\n");
334 		goto error_iio_unreg;
335 	}
336 
337 	return ret;
338 
339 error_iio_unreg:
340 	iio_device_unregister(indio_dev);
341 error_remove_trigger:
342 	hid_sensor_remove_trigger(&prox_state->common_attributes);
343 error_unreg_buffer_funcs:
344 	iio_triggered_buffer_cleanup(indio_dev);
345 error_free_dev_mem:
346 	kfree(indio_dev->channels);
347 	return ret;
348 }
349 
350 /* Function to deinitialize the processing for usage id */
351 static int hid_prox_remove(struct platform_device *pdev)
352 {
353 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
354 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
355 	struct prox_state *prox_state = iio_priv(indio_dev);
356 
357 	sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_PROX);
358 	iio_device_unregister(indio_dev);
359 	hid_sensor_remove_trigger(&prox_state->common_attributes);
360 	iio_triggered_buffer_cleanup(indio_dev);
361 	kfree(indio_dev->channels);
362 
363 	return 0;
364 }
365 
366 static struct platform_device_id hid_prox_ids[] = {
367 	{
368 		/* Format: HID-SENSOR-usage_id_in_hex_lowercase */
369 		.name = "HID-SENSOR-200011",
370 	},
371 	{ /* sentinel */ }
372 };
373 MODULE_DEVICE_TABLE(platform, hid_prox_ids);
374 
375 static struct platform_driver hid_prox_platform_driver = {
376 	.id_table = hid_prox_ids,
377 	.driver = {
378 		.name	= KBUILD_MODNAME,
379 		.owner	= THIS_MODULE,
380 	},
381 	.probe		= hid_prox_probe,
382 	.remove		= hid_prox_remove,
383 };
384 module_platform_driver(hid_prox_platform_driver);
385 
386 MODULE_DESCRIPTION("HID Sensor Proximity");
387 MODULE_AUTHOR("Archana Patni <archana.patni@intel.com>");
388 MODULE_LICENSE("GPL");
389