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/interrupt.h>
10 #include <linux/irq.h>
11 #include <linux/slab.h>
12 #include <linux/delay.h>
13 #include <linux/hid-sensor-hub.h>
14 #include <linux/iio/iio.h>
15 #include <linux/iio/sysfs.h>
16 #include <linux/iio/buffer.h>
17 #include "../common/hid-sensors/hid-sensor-trigger.h"
18 
19 #define CHANNEL_SCAN_INDEX_PRESENCE 0
20 
21 struct prox_state {
22 	struct hid_sensor_hub_callbacks callbacks;
23 	struct hid_sensor_common common_attributes;
24 	struct hid_sensor_hub_attribute_info prox_attr;
25 	u32 human_presence;
26 	int scale_pre_decml;
27 	int scale_post_decml;
28 	int scale_precision;
29 };
30 
31 /* Channel definitions */
32 static const struct iio_chan_spec prox_channels[] = {
33 	{
34 		.type = IIO_PROXIMITY,
35 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
36 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
37 		BIT(IIO_CHAN_INFO_SCALE) |
38 		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
39 		BIT(IIO_CHAN_INFO_HYSTERESIS),
40 		.scan_index = CHANNEL_SCAN_INDEX_PRESENCE,
41 	}
42 };
43 
44 /* Adjust channel real bits based on report descriptor */
45 static void prox_adjust_channel_bit_mask(struct iio_chan_spec *channels,
46 					int channel, int size)
47 {
48 	channels[channel].scan_type.sign = 's';
49 	/* Real storage bits will change based on the report desc. */
50 	channels[channel].scan_type.realbits = size * 8;
51 	/* Maximum size of a sample to capture is u32 */
52 	channels[channel].scan_type.storagebits = sizeof(u32) * 8;
53 }
54 
55 /* Channel read_raw handler */
56 static int prox_read_raw(struct iio_dev *indio_dev,
57 			      struct iio_chan_spec const *chan,
58 			      int *val, int *val2,
59 			      long mask)
60 {
61 	struct prox_state *prox_state = iio_priv(indio_dev);
62 	int report_id = -1;
63 	u32 address;
64 	int ret_type;
65 	s32 min;
66 
67 	*val = 0;
68 	*val2 = 0;
69 	switch (mask) {
70 	case IIO_CHAN_INFO_RAW:
71 		switch (chan->scan_index) {
72 		case  CHANNEL_SCAN_INDEX_PRESENCE:
73 			report_id = prox_state->prox_attr.report_id;
74 			min = prox_state->prox_attr.logical_minimum;
75 			address = HID_USAGE_SENSOR_HUMAN_PRESENCE;
76 			break;
77 		default:
78 			report_id = -1;
79 			break;
80 		}
81 		if (report_id >= 0) {
82 			hid_sensor_power_state(&prox_state->common_attributes,
83 						true);
84 			*val = sensor_hub_input_attr_get_raw_value(
85 				prox_state->common_attributes.hsdev,
86 				HID_USAGE_SENSOR_PROX, address,
87 				report_id,
88 				SENSOR_HUB_SYNC,
89 				min < 0);
90 			hid_sensor_power_state(&prox_state->common_attributes,
91 						false);
92 		} else {
93 			*val = 0;
94 			return -EINVAL;
95 		}
96 		ret_type = IIO_VAL_INT;
97 		break;
98 	case IIO_CHAN_INFO_SCALE:
99 		*val = prox_state->scale_pre_decml;
100 		*val2 = prox_state->scale_post_decml;
101 		ret_type = prox_state->scale_precision;
102 		break;
103 	case IIO_CHAN_INFO_OFFSET:
104 		*val = hid_sensor_convert_exponent(
105 				prox_state->prox_attr.unit_expo);
106 		ret_type = IIO_VAL_INT;
107 		break;
108 	case IIO_CHAN_INFO_SAMP_FREQ:
109 		ret_type = hid_sensor_read_samp_freq_value(
110 				&prox_state->common_attributes, val, val2);
111 		break;
112 	case IIO_CHAN_INFO_HYSTERESIS:
113 		ret_type = hid_sensor_read_raw_hyst_value(
114 				&prox_state->common_attributes, val, val2);
115 		break;
116 	default:
117 		ret_type = -EINVAL;
118 		break;
119 	}
120 
121 	return ret_type;
122 }
123 
124 /* Channel write_raw handler */
125 static int prox_write_raw(struct iio_dev *indio_dev,
126 			       struct iio_chan_spec const *chan,
127 			       int val,
128 			       int val2,
129 			       long mask)
130 {
131 	struct prox_state *prox_state = iio_priv(indio_dev);
132 	int ret = 0;
133 
134 	switch (mask) {
135 	case IIO_CHAN_INFO_SAMP_FREQ:
136 		ret = hid_sensor_write_samp_freq_value(
137 				&prox_state->common_attributes, val, val2);
138 		break;
139 	case IIO_CHAN_INFO_HYSTERESIS:
140 		ret = hid_sensor_write_raw_hyst_value(
141 				&prox_state->common_attributes, val, val2);
142 		break;
143 	default:
144 		ret = -EINVAL;
145 	}
146 
147 	return ret;
148 }
149 
150 static const struct iio_info prox_info = {
151 	.read_raw = &prox_read_raw,
152 	.write_raw = &prox_write_raw,
153 };
154 
155 /* Function to push data to buffer */
156 static void hid_sensor_push_data(struct iio_dev *indio_dev, const void *data,
157 					int len)
158 {
159 	dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n");
160 	iio_push_to_buffers(indio_dev, data);
161 }
162 
163 /* Callback handler to send event after all samples are received and captured */
164 static int prox_proc_event(struct hid_sensor_hub_device *hsdev,
165 				unsigned usage_id,
166 				void *priv)
167 {
168 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
169 	struct prox_state *prox_state = iio_priv(indio_dev);
170 
171 	dev_dbg(&indio_dev->dev, "prox_proc_event\n");
172 	if (atomic_read(&prox_state->common_attributes.data_ready))
173 		hid_sensor_push_data(indio_dev,
174 				&prox_state->human_presence,
175 				sizeof(prox_state->human_presence));
176 
177 	return 0;
178 }
179 
180 /* Capture samples in local storage */
181 static int prox_capture_sample(struct hid_sensor_hub_device *hsdev,
182 				unsigned usage_id,
183 				size_t raw_len, char *raw_data,
184 				void *priv)
185 {
186 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
187 	struct prox_state *prox_state = iio_priv(indio_dev);
188 	int ret = -EINVAL;
189 
190 	switch (usage_id) {
191 	case HID_USAGE_SENSOR_HUMAN_PRESENCE:
192 		prox_state->human_presence = *(u32 *)raw_data;
193 		ret = 0;
194 		break;
195 	default:
196 		break;
197 	}
198 
199 	return ret;
200 }
201 
202 /* Parse report which is specific to an usage id*/
203 static int prox_parse_report(struct platform_device *pdev,
204 				struct hid_sensor_hub_device *hsdev,
205 				struct iio_chan_spec *channels,
206 				unsigned usage_id,
207 				struct prox_state *st)
208 {
209 	int ret;
210 
211 	ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
212 			usage_id,
213 			HID_USAGE_SENSOR_HUMAN_PRESENCE,
214 			&st->prox_attr);
215 	if (ret < 0)
216 		return ret;
217 	prox_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_PRESENCE,
218 					st->prox_attr.size);
219 
220 	dev_dbg(&pdev->dev, "prox %x:%x\n", st->prox_attr.index,
221 			st->prox_attr.report_id);
222 
223 	/* Set Sensitivity field ids, when there is no individual modifier */
224 	if (st->common_attributes.sensitivity.index < 0) {
225 		sensor_hub_input_get_attribute_info(hsdev,
226 			HID_FEATURE_REPORT, usage_id,
227 			HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS |
228 			HID_USAGE_SENSOR_DATA_PRESENCE,
229 			&st->common_attributes.sensitivity);
230 		dev_dbg(&pdev->dev, "Sensitivity index:report %d:%d\n",
231 			st->common_attributes.sensitivity.index,
232 			st->common_attributes.sensitivity.report_id);
233 	}
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_HUMAN_PRESENCE,
239 			&st->common_attributes.sensitivity);
240 
241 	st->scale_precision = hid_sensor_format_scale(
242 				hsdev->usage,
243 				&st->prox_attr,
244 				&st->scale_pre_decml, &st->scale_post_decml);
245 
246 	return ret;
247 }
248 
249 /* Function to initialize the processing for usage id */
250 static int hid_prox_probe(struct platform_device *pdev)
251 {
252 	int ret = 0;
253 	static const char *name = "prox";
254 	struct iio_dev *indio_dev;
255 	struct prox_state *prox_state;
256 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
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 	indio_dev->channels = kmemdup(prox_channels, sizeof(prox_channels),
276 				      GFP_KERNEL);
277 	if (!indio_dev->channels) {
278 		dev_err(&pdev->dev, "failed to duplicate channels\n");
279 		return -ENOMEM;
280 	}
281 
282 	ret = prox_parse_report(pdev, hsdev,
283 				(struct iio_chan_spec *)indio_dev->channels,
284 				HID_USAGE_SENSOR_PROX, prox_state);
285 	if (ret) {
286 		dev_err(&pdev->dev, "failed to setup attributes\n");
287 		goto error_free_dev_mem;
288 	}
289 
290 	indio_dev->num_channels = ARRAY_SIZE(prox_channels);
291 	indio_dev->info = &prox_info;
292 	indio_dev->name = name;
293 	indio_dev->modes = INDIO_DIRECT_MODE;
294 
295 	atomic_set(&prox_state->common_attributes.data_ready, 0);
296 
297 	ret = hid_sensor_setup_trigger(indio_dev, name,
298 				&prox_state->common_attributes);
299 	if (ret) {
300 		dev_err(&pdev->dev, "trigger setup failed\n");
301 		goto error_free_dev_mem;
302 	}
303 
304 	ret = iio_device_register(indio_dev);
305 	if (ret) {
306 		dev_err(&pdev->dev, "device register failed\n");
307 		goto error_remove_trigger;
308 	}
309 
310 	prox_state->callbacks.send_event = prox_proc_event;
311 	prox_state->callbacks.capture_sample = prox_capture_sample;
312 	prox_state->callbacks.pdev = pdev;
313 	ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_PROX,
314 					&prox_state->callbacks);
315 	if (ret < 0) {
316 		dev_err(&pdev->dev, "callback reg failed\n");
317 		goto error_iio_unreg;
318 	}
319 
320 	return ret;
321 
322 error_iio_unreg:
323 	iio_device_unregister(indio_dev);
324 error_remove_trigger:
325 	hid_sensor_remove_trigger(indio_dev, &prox_state->common_attributes);
326 error_free_dev_mem:
327 	kfree(indio_dev->channels);
328 	return ret;
329 }
330 
331 /* Function to deinitialize the processing for usage id */
332 static int hid_prox_remove(struct platform_device *pdev)
333 {
334 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
335 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
336 	struct prox_state *prox_state = iio_priv(indio_dev);
337 
338 	sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_PROX);
339 	iio_device_unregister(indio_dev);
340 	hid_sensor_remove_trigger(indio_dev, &prox_state->common_attributes);
341 	kfree(indio_dev->channels);
342 
343 	return 0;
344 }
345 
346 static const struct platform_device_id hid_prox_ids[] = {
347 	{
348 		/* Format: HID-SENSOR-usage_id_in_hex_lowercase */
349 		.name = "HID-SENSOR-200011",
350 	},
351 	{ /* sentinel */ }
352 };
353 MODULE_DEVICE_TABLE(platform, hid_prox_ids);
354 
355 static struct platform_driver hid_prox_platform_driver = {
356 	.id_table = hid_prox_ids,
357 	.driver = {
358 		.name	= KBUILD_MODNAME,
359 		.pm	= &hid_sensor_pm_ops,
360 	},
361 	.probe		= hid_prox_probe,
362 	.remove		= hid_prox_remove,
363 };
364 module_platform_driver(hid_prox_platform_driver);
365 
366 MODULE_DESCRIPTION("HID Sensor Proximity");
367 MODULE_AUTHOR("Archana Patni <archana.patni@intel.com>");
368 MODULE_LICENSE("GPL");
369