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 	int scale_pre_decml;
41 	int scale_post_decml;
42 	int scale_precision;
43 };
44 
45 /* Channel definitions */
46 static const struct iio_chan_spec prox_channels[] = {
47 	{
48 		.type = IIO_PROXIMITY,
49 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
50 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
51 		BIT(IIO_CHAN_INFO_SCALE) |
52 		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
53 		BIT(IIO_CHAN_INFO_HYSTERESIS),
54 		.scan_index = CHANNEL_SCAN_INDEX_PRESENCE,
55 	}
56 };
57 
58 /* Adjust channel real bits based on report descriptor */
prox_adjust_channel_bit_mask(struct iio_chan_spec * channels,int channel,int size)59 static void prox_adjust_channel_bit_mask(struct iio_chan_spec *channels,
60 					int channel, int size)
61 {
62 	channels[channel].scan_type.sign = 's';
63 	/* Real storage bits will change based on the report desc. */
64 	channels[channel].scan_type.realbits = size * 8;
65 	/* Maximum size of a sample to capture is u32 */
66 	channels[channel].scan_type.storagebits = sizeof(u32) * 8;
67 }
68 
69 /* Channel read_raw handler */
prox_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)70 static int prox_read_raw(struct iio_dev *indio_dev,
71 			      struct iio_chan_spec const *chan,
72 			      int *val, int *val2,
73 			      long mask)
74 {
75 	struct prox_state *prox_state = iio_priv(indio_dev);
76 	int report_id = -1;
77 	u32 address;
78 	int ret_type;
79 	s32 min;
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 			min = prox_state->prox_attr.logical_minimum;
89 			address = HID_USAGE_SENSOR_HUMAN_PRESENCE;
90 			break;
91 		default:
92 			report_id = -1;
93 			break;
94 		}
95 		if (report_id >= 0) {
96 			hid_sensor_power_state(&prox_state->common_attributes,
97 						true);
98 			*val = sensor_hub_input_attr_get_raw_value(
99 				prox_state->common_attributes.hsdev,
100 				HID_USAGE_SENSOR_PROX, address,
101 				report_id,
102 				SENSOR_HUB_SYNC,
103 				min < 0);
104 			hid_sensor_power_state(&prox_state->common_attributes,
105 						false);
106 		} else {
107 			*val = 0;
108 			return -EINVAL;
109 		}
110 		ret_type = IIO_VAL_INT;
111 		break;
112 	case IIO_CHAN_INFO_SCALE:
113 		*val = prox_state->scale_pre_decml;
114 		*val2 = prox_state->scale_post_decml;
115 		ret_type = prox_state->scale_precision;
116 		break;
117 	case IIO_CHAN_INFO_OFFSET:
118 		*val = hid_sensor_convert_exponent(
119 				prox_state->prox_attr.unit_expo);
120 		ret_type = IIO_VAL_INT;
121 		break;
122 	case IIO_CHAN_INFO_SAMP_FREQ:
123 		ret_type = hid_sensor_read_samp_freq_value(
124 				&prox_state->common_attributes, val, val2);
125 		break;
126 	case IIO_CHAN_INFO_HYSTERESIS:
127 		ret_type = hid_sensor_read_raw_hyst_value(
128 				&prox_state->common_attributes, val, val2);
129 		break;
130 	default:
131 		ret_type = -EINVAL;
132 		break;
133 	}
134 
135 	return ret_type;
136 }
137 
138 /* Channel write_raw handler */
prox_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)139 static int prox_write_raw(struct iio_dev *indio_dev,
140 			       struct iio_chan_spec const *chan,
141 			       int val,
142 			       int val2,
143 			       long mask)
144 {
145 	struct prox_state *prox_state = iio_priv(indio_dev);
146 	int ret = 0;
147 
148 	switch (mask) {
149 	case IIO_CHAN_INFO_SAMP_FREQ:
150 		ret = hid_sensor_write_samp_freq_value(
151 				&prox_state->common_attributes, val, val2);
152 		break;
153 	case IIO_CHAN_INFO_HYSTERESIS:
154 		ret = hid_sensor_write_raw_hyst_value(
155 				&prox_state->common_attributes, val, val2);
156 		break;
157 	default:
158 		ret = -EINVAL;
159 	}
160 
161 	return ret;
162 }
163 
164 static const struct iio_info prox_info = {
165 	.read_raw = &prox_read_raw,
166 	.write_raw = &prox_write_raw,
167 };
168 
169 /* Function to push data to buffer */
hid_sensor_push_data(struct iio_dev * indio_dev,const void * data,int len)170 static void hid_sensor_push_data(struct iio_dev *indio_dev, const void *data,
171 					int len)
172 {
173 	dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n");
174 	iio_push_to_buffers(indio_dev, data);
175 }
176 
177 /* Callback handler to send event after all samples are received and captured */
prox_proc_event(struct hid_sensor_hub_device * hsdev,unsigned usage_id,void * priv)178 static int prox_proc_event(struct hid_sensor_hub_device *hsdev,
179 				unsigned usage_id,
180 				void *priv)
181 {
182 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
183 	struct prox_state *prox_state = iio_priv(indio_dev);
184 
185 	dev_dbg(&indio_dev->dev, "prox_proc_event\n");
186 	if (atomic_read(&prox_state->common_attributes.data_ready))
187 		hid_sensor_push_data(indio_dev,
188 				&prox_state->human_presence,
189 				sizeof(prox_state->human_presence));
190 
191 	return 0;
192 }
193 
194 /* Capture samples in local storage */
prox_capture_sample(struct hid_sensor_hub_device * hsdev,unsigned usage_id,size_t raw_len,char * raw_data,void * priv)195 static int prox_capture_sample(struct hid_sensor_hub_device *hsdev,
196 				unsigned usage_id,
197 				size_t raw_len, char *raw_data,
198 				void *priv)
199 {
200 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
201 	struct prox_state *prox_state = iio_priv(indio_dev);
202 	int ret = -EINVAL;
203 
204 	switch (usage_id) {
205 	case HID_USAGE_SENSOR_HUMAN_PRESENCE:
206 		prox_state->human_presence = *(u32 *)raw_data;
207 		ret = 0;
208 		break;
209 	default:
210 		break;
211 	}
212 
213 	return ret;
214 }
215 
216 /* Parse report which is specific to an usage id*/
prox_parse_report(struct platform_device * pdev,struct hid_sensor_hub_device * hsdev,struct iio_chan_spec * channels,unsigned usage_id,struct prox_state * st)217 static int prox_parse_report(struct platform_device *pdev,
218 				struct hid_sensor_hub_device *hsdev,
219 				struct iio_chan_spec *channels,
220 				unsigned usage_id,
221 				struct prox_state *st)
222 {
223 	int ret;
224 
225 	ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
226 			usage_id,
227 			HID_USAGE_SENSOR_HUMAN_PRESENCE,
228 			&st->prox_attr);
229 	if (ret < 0)
230 		return ret;
231 	prox_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_PRESENCE,
232 					st->prox_attr.size);
233 
234 	dev_dbg(&pdev->dev, "prox %x:%x\n", st->prox_attr.index,
235 			st->prox_attr.report_id);
236 
237 	/* Set Sensitivity field ids, when there is no individual modifier */
238 	if (st->common_attributes.sensitivity.index < 0) {
239 		sensor_hub_input_get_attribute_info(hsdev,
240 			HID_FEATURE_REPORT, usage_id,
241 			HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS |
242 			HID_USAGE_SENSOR_DATA_PRESENCE,
243 			&st->common_attributes.sensitivity);
244 		dev_dbg(&pdev->dev, "Sensitivity index:report %d:%d\n",
245 			st->common_attributes.sensitivity.index,
246 			st->common_attributes.sensitivity.report_id);
247 	}
248 	if (st->common_attributes.sensitivity.index < 0)
249 		sensor_hub_input_get_attribute_info(hsdev,
250 			HID_FEATURE_REPORT, usage_id,
251 			HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS |
252 			HID_USAGE_SENSOR_HUMAN_PRESENCE,
253 			&st->common_attributes.sensitivity);
254 
255 	st->scale_precision = hid_sensor_format_scale(
256 				hsdev->usage,
257 				&st->prox_attr,
258 				&st->scale_pre_decml, &st->scale_post_decml);
259 
260 	return ret;
261 }
262 
263 /* Function to initialize the processing for usage id */
hid_prox_probe(struct platform_device * pdev)264 static int hid_prox_probe(struct platform_device *pdev)
265 {
266 	int ret = 0;
267 	static const char *name = "prox";
268 	struct iio_dev *indio_dev;
269 	struct prox_state *prox_state;
270 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
271 
272 	indio_dev = devm_iio_device_alloc(&pdev->dev,
273 				sizeof(struct prox_state));
274 	if (!indio_dev)
275 		return -ENOMEM;
276 	platform_set_drvdata(pdev, indio_dev);
277 
278 	prox_state = iio_priv(indio_dev);
279 	prox_state->common_attributes.hsdev = hsdev;
280 	prox_state->common_attributes.pdev = pdev;
281 
282 	ret = hid_sensor_parse_common_attributes(hsdev, HID_USAGE_SENSOR_PROX,
283 					&prox_state->common_attributes);
284 	if (ret) {
285 		dev_err(&pdev->dev, "failed to setup common attributes\n");
286 		return ret;
287 	}
288 
289 	indio_dev->channels = kmemdup(prox_channels, sizeof(prox_channels),
290 				      GFP_KERNEL);
291 	if (!indio_dev->channels) {
292 		dev_err(&pdev->dev, "failed to duplicate channels\n");
293 		return -ENOMEM;
294 	}
295 
296 	ret = prox_parse_report(pdev, hsdev,
297 				(struct iio_chan_spec *)indio_dev->channels,
298 				HID_USAGE_SENSOR_PROX, prox_state);
299 	if (ret) {
300 		dev_err(&pdev->dev, "failed to setup attributes\n");
301 		goto error_free_dev_mem;
302 	}
303 
304 	indio_dev->num_channels = ARRAY_SIZE(prox_channels);
305 	indio_dev->dev.parent = &pdev->dev;
306 	indio_dev->info = &prox_info;
307 	indio_dev->name = name;
308 	indio_dev->modes = INDIO_DIRECT_MODE;
309 
310 	ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
311 		NULL, NULL);
312 	if (ret) {
313 		dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
314 		goto error_free_dev_mem;
315 	}
316 	atomic_set(&prox_state->common_attributes.data_ready, 0);
317 	ret = hid_sensor_setup_trigger(indio_dev, name,
318 				&prox_state->common_attributes);
319 	if (ret) {
320 		dev_err(&pdev->dev, "trigger setup failed\n");
321 		goto error_unreg_buffer_funcs;
322 	}
323 
324 	ret = iio_device_register(indio_dev);
325 	if (ret) {
326 		dev_err(&pdev->dev, "device register failed\n");
327 		goto error_remove_trigger;
328 	}
329 
330 	prox_state->callbacks.send_event = prox_proc_event;
331 	prox_state->callbacks.capture_sample = prox_capture_sample;
332 	prox_state->callbacks.pdev = pdev;
333 	ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_PROX,
334 					&prox_state->callbacks);
335 	if (ret < 0) {
336 		dev_err(&pdev->dev, "callback reg failed\n");
337 		goto error_iio_unreg;
338 	}
339 
340 	return ret;
341 
342 error_iio_unreg:
343 	iio_device_unregister(indio_dev);
344 error_remove_trigger:
345 	hid_sensor_remove_trigger(&prox_state->common_attributes);
346 error_unreg_buffer_funcs:
347 	iio_triggered_buffer_cleanup(indio_dev);
348 error_free_dev_mem:
349 	kfree(indio_dev->channels);
350 	return ret;
351 }
352 
353 /* Function to deinitialize the processing for usage id */
hid_prox_remove(struct platform_device * pdev)354 static int hid_prox_remove(struct platform_device *pdev)
355 {
356 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
357 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
358 	struct prox_state *prox_state = iio_priv(indio_dev);
359 
360 	sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_PROX);
361 	iio_device_unregister(indio_dev);
362 	hid_sensor_remove_trigger(&prox_state->common_attributes);
363 	iio_triggered_buffer_cleanup(indio_dev);
364 	kfree(indio_dev->channels);
365 
366 	return 0;
367 }
368 
369 static const struct platform_device_id hid_prox_ids[] = {
370 	{
371 		/* Format: HID-SENSOR-usage_id_in_hex_lowercase */
372 		.name = "HID-SENSOR-200011",
373 	},
374 	{ /* sentinel */ }
375 };
376 MODULE_DEVICE_TABLE(platform, hid_prox_ids);
377 
378 static struct platform_driver hid_prox_platform_driver = {
379 	.id_table = hid_prox_ids,
380 	.driver = {
381 		.name	= KBUILD_MODNAME,
382 		.pm	= &hid_sensor_pm_ops,
383 	},
384 	.probe		= hid_prox_probe,
385 	.remove		= hid_prox_remove,
386 };
387 module_platform_driver(hid_prox_platform_driver);
388 
389 MODULE_DESCRIPTION("HID Sensor Proximity");
390 MODULE_AUTHOR("Archana Patni <archana.patni@intel.com>");
391 MODULE_LICENSE("GPL");
392