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