xref: /linux/drivers/iio/light/hid-sensor-prox.c (revision 113ff0e048ff11e4c52ae97f9fa59fd39c1c0f6a)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * HID Sensors Driver
4  * Copyright (c) 2014, Intel Corporation.
5  */
6 #include <linux/device.h>
7 #include <linux/platform_device.h>
8 #include <linux/module.h>
9 #include <linux/mod_devicetable.h>
10 #include <linux/slab.h>
11 #include <linux/hid-sensor-hub.h>
12 #include <linux/iio/iio.h>
13 #include <linux/iio/buffer.h>
14 #include "../common/hid-sensors/hid-sensor-trigger.h"
15 
16 static const u32 prox_usage_ids[] = {
17 	HID_USAGE_SENSOR_HUMAN_PRESENCE,
18 	HID_USAGE_SENSOR_HUMAN_PROXIMITY,
19 	HID_USAGE_SENSOR_HUMAN_ATTENTION,
20 };
21 
22 #define MAX_CHANNELS ARRAY_SIZE(prox_usage_ids)
23 
24 enum {
25 	HID_HUMAN_PRESENCE,
26 	HID_HUMAN_PROXIMITY,
27 	HID_HUMAN_ATTENTION,
28 };
29 
30 struct prox_state {
31 	struct hid_sensor_hub_callbacks callbacks;
32 	struct hid_sensor_common common_attributes;
33 	struct hid_sensor_hub_attribute_info prox_attr[MAX_CHANNELS];
34 	struct iio_chan_spec channels[MAX_CHANNELS];
35 	u32 channel2usage[MAX_CHANNELS];
36 	u32 human_presence[MAX_CHANNELS];
37 	int scale_pre_decml;
38 	int scale_post_decml;
39 	int scale_precision;
40 	unsigned long scan_mask[2]; /* One entry plus one terminator. */
41 	int num_channels;
42 };
43 
44 static const u32 prox_sensitivity_addresses[] = {
45 	HID_USAGE_SENSOR_HUMAN_PRESENCE,
46 	HID_USAGE_SENSOR_DATA_PRESENCE,
47 };
48 
49 #define PROX_CHANNEL(_is_proximity, _channel) \
50 	{\
51 		.type = _is_proximity ? IIO_PROXIMITY : IIO_ATTENTION,\
52 		.info_mask_separate = _is_proximity ? BIT(IIO_CHAN_INFO_RAW) :\
53 				      BIT(IIO_CHAN_INFO_PROCESSED),\
54 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |\
55 		BIT(IIO_CHAN_INFO_SCALE) |\
56 		BIT(IIO_CHAN_INFO_SAMP_FREQ) |\
57 		BIT(IIO_CHAN_INFO_HYSTERESIS),\
58 		.indexed = _is_proximity,\
59 		.channel = _channel,\
60 	}
61 
62 /* Channel definitions (same order as prox_usage_ids) */
63 static const struct iio_chan_spec prox_channels[] = {
64 	PROX_CHANNEL(true, HID_HUMAN_PRESENCE),
65 	PROX_CHANNEL(true, HID_HUMAN_PROXIMITY),
66 	PROX_CHANNEL(false, 0),
67 };
68 
69 /* Adjust channel real bits based on report descriptor */
70 static void prox_adjust_channel_bit_mask(struct iio_chan_spec *channels,
71 					int channel, int size)
72 {
73 	channels[channel].scan_type.sign = 's';
74 	/* Real storage bits will change based on the report desc. */
75 	channels[channel].scan_type.realbits = size * 8;
76 	/* Maximum size of a sample to capture is u32 */
77 	channels[channel].scan_type.storagebits = sizeof(u32) * 8;
78 }
79 
80 /* Channel read_raw handler */
81 static int prox_read_raw(struct iio_dev *indio_dev,
82 			      struct iio_chan_spec const *chan,
83 			      int *val, int *val2,
84 			      long mask)
85 {
86 	struct prox_state *prox_state = iio_priv(indio_dev);
87 	struct hid_sensor_hub_device *hsdev;
88 	int report_id;
89 	u32 address;
90 	int ret_type;
91 	s32 min;
92 
93 	*val = 0;
94 	*val2 = 0;
95 	switch (mask) {
96 	case IIO_CHAN_INFO_RAW:
97 	case IIO_CHAN_INFO_PROCESSED:
98 		if (chan->scan_index >= prox_state->num_channels)
99 			return -EINVAL;
100 		address = prox_state->channel2usage[chan->scan_index];
101 		report_id = prox_state->prox_attr[chan->scan_index].report_id;
102 		hsdev = prox_state->common_attributes.hsdev;
103 		min = prox_state->prox_attr[chan->scan_index].logical_minimum;
104 		hid_sensor_power_state(&prox_state->common_attributes, true);
105 		*val = sensor_hub_input_attr_get_raw_value(hsdev,
106 							   hsdev->usage,
107 							   address,
108 							   report_id,
109 							   SENSOR_HUB_SYNC,
110 							   min < 0);
111 		if (prox_state->channel2usage[chan->scan_index] ==
112 		    HID_USAGE_SENSOR_HUMAN_ATTENTION)
113 			*val *= 100;
114 		hid_sensor_power_state(&prox_state->common_attributes, false);
115 		ret_type = IIO_VAL_INT;
116 		break;
117 	case IIO_CHAN_INFO_SCALE:
118 		*val = prox_state->scale_pre_decml;
119 		*val2 = prox_state->scale_post_decml;
120 		ret_type = prox_state->scale_precision;
121 		break;
122 	case IIO_CHAN_INFO_OFFSET:
123 		*val = hid_sensor_convert_exponent(
124 			prox_state->prox_attr[chan->scan_index].unit_expo);
125 		ret_type = IIO_VAL_INT;
126 		break;
127 	case IIO_CHAN_INFO_SAMP_FREQ:
128 		ret_type = hid_sensor_read_samp_freq_value(
129 				&prox_state->common_attributes, val, val2);
130 		break;
131 	case IIO_CHAN_INFO_HYSTERESIS:
132 		ret_type = hid_sensor_read_raw_hyst_value(
133 				&prox_state->common_attributes, val, val2);
134 		break;
135 	default:
136 		ret_type = -EINVAL;
137 		break;
138 	}
139 
140 	return ret_type;
141 }
142 
143 /* Channel write_raw handler */
144 static int prox_write_raw(struct iio_dev *indio_dev,
145 			       struct iio_chan_spec const *chan,
146 			       int val,
147 			       int val2,
148 			       long mask)
149 {
150 	struct prox_state *prox_state = iio_priv(indio_dev);
151 	int ret = 0;
152 
153 	switch (mask) {
154 	case IIO_CHAN_INFO_SAMP_FREQ:
155 		ret = hid_sensor_write_samp_freq_value(
156 				&prox_state->common_attributes, val, val2);
157 		break;
158 	case IIO_CHAN_INFO_HYSTERESIS:
159 		ret = hid_sensor_write_raw_hyst_value(
160 				&prox_state->common_attributes, val, val2);
161 		break;
162 	default:
163 		ret = -EINVAL;
164 	}
165 
166 	return ret;
167 }
168 
169 static const struct iio_info prox_info = {
170 	.read_raw = &prox_read_raw,
171 	.write_raw = &prox_write_raw,
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 		dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n");
185 		iio_push_to_buffers(indio_dev, &prox_state->human_presence);
186 	}
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 multiplier = 1;
200 	int chan;
201 
202 	for (chan = 0; chan < prox_state->num_channels; chan++)
203 		if (prox_state->channel2usage[chan] == usage_id)
204 			break;
205 	if (chan == prox_state->num_channels)
206 		return -EINVAL;
207 
208 	if (usage_id == HID_USAGE_SENSOR_HUMAN_ATTENTION)
209 		multiplier = 100;
210 
211 	switch (raw_len) {
212 	case 1:
213 		prox_state->human_presence[chan] = *(u8 *)raw_data * multiplier;
214 		return 0;
215 	case 4:
216 		prox_state->human_presence[chan] = *(u32 *)raw_data * multiplier;
217 		return 0;
218 	}
219 
220 	return -EINVAL;
221 }
222 
223 /* Parse report which is specific to an usage id*/
224 static int prox_parse_report(struct platform_device *pdev,
225 				struct hid_sensor_hub_device *hsdev,
226 				struct prox_state *st)
227 {
228 	struct iio_chan_spec *channels = st->channels;
229 	int index = 0;
230 	int ret;
231 	int i;
232 
233 	for (i = 0; i < MAX_CHANNELS; i++) {
234 		u32 usage_id = prox_usage_ids[i];
235 
236 		ret = sensor_hub_input_get_attribute_info(hsdev,
237 							  HID_INPUT_REPORT,
238 							  hsdev->usage,
239 							  usage_id,
240 							  &st->prox_attr[index]);
241 		if (ret < 0)
242 			continue;
243 		st->channel2usage[index] = usage_id;
244 		st->scan_mask[0] |= BIT(index);
245 		channels[index] = prox_channels[i];
246 		channels[index].scan_index = index;
247 		prox_adjust_channel_bit_mask(channels, index,
248 					     st->prox_attr[index].size);
249 		dev_dbg(&pdev->dev, "prox %x:%x\n", st->prox_attr[index].index,
250 			st->prox_attr[index].report_id);
251 		index++;
252 	}
253 
254 	if (!index)
255 		return ret;
256 
257 	st->num_channels = index;
258 
259 	return 0;
260 }
261 
262 /* Function to initialize the processing for usage id */
263 static int hid_prox_probe(struct platform_device *pdev)
264 {
265 	struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);
266 	int ret = 0;
267 	static const char *name = "prox";
268 	struct iio_dev *indio_dev;
269 	struct prox_state *prox_state;
270 
271 	indio_dev = devm_iio_device_alloc(&pdev->dev,
272 				sizeof(struct prox_state));
273 	if (!indio_dev)
274 		return -ENOMEM;
275 	platform_set_drvdata(pdev, indio_dev);
276 
277 	prox_state = iio_priv(indio_dev);
278 	prox_state->common_attributes.hsdev = hsdev;
279 	prox_state->common_attributes.pdev = pdev;
280 
281 	ret = hid_sensor_parse_common_attributes(hsdev, hsdev->usage,
282 					&prox_state->common_attributes,
283 					prox_sensitivity_addresses,
284 					ARRAY_SIZE(prox_sensitivity_addresses));
285 	if (ret) {
286 		dev_err(&pdev->dev, "failed to setup common attributes\n");
287 		return ret;
288 	}
289 
290 	ret = prox_parse_report(pdev, hsdev, prox_state);
291 	if (ret) {
292 		dev_err(&pdev->dev, "failed to setup attributes\n");
293 		return ret;
294 	}
295 
296 	indio_dev->num_channels = prox_state->num_channels;
297 	indio_dev->channels = prox_state->channels;
298 	indio_dev->available_scan_masks = prox_state->scan_mask;
299 	indio_dev->info = &prox_info;
300 	indio_dev->name = name;
301 	indio_dev->modes = INDIO_DIRECT_MODE;
302 
303 	atomic_set(&prox_state->common_attributes.data_ready, 0);
304 
305 	ret = hid_sensor_setup_trigger(indio_dev, name,
306 				&prox_state->common_attributes);
307 	if (ret) {
308 		dev_err(&pdev->dev, "trigger setup failed\n");
309 		return ret;
310 	}
311 
312 	ret = iio_device_register(indio_dev);
313 	if (ret) {
314 		dev_err(&pdev->dev, "device register failed\n");
315 		goto error_remove_trigger;
316 	}
317 
318 	prox_state->callbacks.send_event = prox_proc_event;
319 	prox_state->callbacks.capture_sample = prox_capture_sample;
320 	prox_state->callbacks.pdev = pdev;
321 	ret = sensor_hub_register_callback(hsdev, hsdev->usage,
322 					   &prox_state->callbacks);
323 	if (ret < 0) {
324 		dev_err(&pdev->dev, "callback reg failed\n");
325 		goto error_iio_unreg;
326 	}
327 
328 	return ret;
329 
330 error_iio_unreg:
331 	iio_device_unregister(indio_dev);
332 error_remove_trigger:
333 	hid_sensor_remove_trigger(indio_dev, &prox_state->common_attributes);
334 	return ret;
335 }
336 
337 /* Function to deinitialize the processing for usage id */
338 static void hid_prox_remove(struct platform_device *pdev)
339 {
340 	struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);
341 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
342 	struct prox_state *prox_state = iio_priv(indio_dev);
343 
344 	sensor_hub_remove_callback(hsdev, hsdev->usage);
345 	iio_device_unregister(indio_dev);
346 	hid_sensor_remove_trigger(indio_dev, &prox_state->common_attributes);
347 }
348 
349 static const struct platform_device_id hid_prox_ids[] = {
350 	{
351 		/* Format: HID-SENSOR-usage_id_in_hex_lowercase */
352 		.name = "HID-SENSOR-200011",
353 	},
354 	{
355 		/* Format: HID-SENSOR-tag-usage_id_in_hex_lowercase */
356 		.name = "HID-SENSOR-LISS-0226",
357 	},
358 	{ /* sentinel */ }
359 };
360 MODULE_DEVICE_TABLE(platform, hid_prox_ids);
361 
362 static struct platform_driver hid_prox_platform_driver = {
363 	.id_table = hid_prox_ids,
364 	.driver = {
365 		.name	= KBUILD_MODNAME,
366 		.pm	= &hid_sensor_pm_ops,
367 	},
368 	.probe		= hid_prox_probe,
369 	.remove		= hid_prox_remove,
370 };
371 module_platform_driver(hid_prox_platform_driver);
372 
373 MODULE_DESCRIPTION("HID Sensor Proximity");
374 MODULE_AUTHOR("Archana Patni <archana.patni@intel.com>");
375 MODULE_LICENSE("GPL");
376 MODULE_IMPORT_NS("IIO_HID");
377