xref: /linux/drivers/iio/position/hid-sensor-custom-intel-hinge.c (revision 26ba30221c03364d6ed9910be8da4c1fd871b07b)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * HID Sensors Driver
4  * Copyright (c) 2020, Intel Corporation.
5  */
6 #include <linux/hid-sensor-hub.h>
7 #include <linux/iio/buffer.h>
8 #include <linux/iio/iio.h>
9 #include <linux/platform_device.h>
10 #include <linux/module.h>
11 
12 #include "../common/hid-sensors/hid-sensor-trigger.h"
13 
14 enum hinge_channel {
15 	CHANNEL_SCAN_INDEX_HINGE_ANGLE,
16 	CHANNEL_SCAN_INDEX_SCREEN_ANGLE,
17 	CHANNEL_SCAN_INDEX_KEYBOARD_ANGLE,
18 	CHANNEL_SCAN_INDEX_MAX,
19 };
20 
21 #define CHANNEL_SCAN_INDEX_TIMESTAMP CHANNEL_SCAN_INDEX_MAX
22 
23 static const u32 hinge_addresses[CHANNEL_SCAN_INDEX_MAX] = {
24 	HID_USAGE_SENSOR_DATA_FIELD_CUSTOM_VALUE(1),
25 	HID_USAGE_SENSOR_DATA_FIELD_CUSTOM_VALUE(2),
26 	HID_USAGE_SENSOR_DATA_FIELD_CUSTOM_VALUE(3)
27 };
28 
29 static const char *const hinge_labels[CHANNEL_SCAN_INDEX_MAX] = { "hinge",
30 								  "screen",
31 								  "keyboard" };
32 
33 struct hinge_state {
34 	struct iio_dev *indio_dev;
35 	struct hid_sensor_hub_attribute_info hinge[CHANNEL_SCAN_INDEX_MAX];
36 	struct hid_sensor_hub_callbacks callbacks;
37 	struct hid_sensor_common common_attributes;
38 	const char *labels[CHANNEL_SCAN_INDEX_MAX];
39 	struct {
40 		u32 hinge_val[3];
41 		aligned_s64 timestamp;
42 	} scan;
43 
44 	int scale_pre_decml;
45 	int scale_post_decml;
46 	int scale_precision;
47 	int value_offset;
48 	u64 timestamp;
49 };
50 
51 static const u32 hinge_sensitivity_addresses[] = {
52 	HID_USAGE_SENSOR_DATA_FIELD_CUSTOM_VALUE(1),
53 };
54 
55 /* Channel definitions */
56 static const struct iio_chan_spec hinge_channels[] = {
57 	{
58 		.type = IIO_ANGL,
59 		.indexed = 1,
60 		.channel = 0,
61 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
62 		.info_mask_shared_by_type =
63 			BIT(IIO_CHAN_INFO_OFFSET) | BIT(IIO_CHAN_INFO_SCALE) |
64 			BIT(IIO_CHAN_INFO_SAMP_FREQ) | BIT(IIO_CHAN_INFO_HYSTERESIS),
65 		.scan_index = CHANNEL_SCAN_INDEX_HINGE_ANGLE,
66 		.scan_type = {
67 			.sign = 's',
68 			.storagebits = 32,
69 		},
70 	}, {
71 		.type = IIO_ANGL,
72 		.indexed = 1,
73 		.channel = 1,
74 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
75 		.info_mask_shared_by_type =
76 			BIT(IIO_CHAN_INFO_OFFSET) | BIT(IIO_CHAN_INFO_SCALE) |
77 			BIT(IIO_CHAN_INFO_SAMP_FREQ) | BIT(IIO_CHAN_INFO_HYSTERESIS),
78 		.scan_index = CHANNEL_SCAN_INDEX_SCREEN_ANGLE,
79 		.scan_type = {
80 			.sign = 's',
81 			.storagebits = 32,
82 		},
83 	}, {
84 		.type = IIO_ANGL,
85 		.indexed = 1,
86 		.channel = 2,
87 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
88 		.info_mask_shared_by_type =
89 			BIT(IIO_CHAN_INFO_OFFSET) | BIT(IIO_CHAN_INFO_SCALE) |
90 			BIT(IIO_CHAN_INFO_SAMP_FREQ) | BIT(IIO_CHAN_INFO_HYSTERESIS),
91 		.scan_index = CHANNEL_SCAN_INDEX_KEYBOARD_ANGLE,
92 		.scan_type = {
93 			.sign = 's',
94 			.storagebits = 32,
95 		},
96 	},
97 	IIO_CHAN_SOFT_TIMESTAMP(CHANNEL_SCAN_INDEX_TIMESTAMP)
98 };
99 
100 /* Adjust channel real bits based on report descriptor */
101 static void hinge_adjust_channel_realbits(struct iio_chan_spec *channels,
102 					  int channel, int size)
103 {
104 	channels[channel].scan_type.realbits = size * 8;
105 }
106 
107 /* Channel read_raw handler */
108 static int hinge_read_raw(struct iio_dev *indio_dev,
109 			  struct iio_chan_spec const *chan, int *val, int *val2,
110 			  long mask)
111 {
112 	struct hinge_state *st = iio_priv(indio_dev);
113 	struct hid_sensor_hub_device *hsdev;
114 	int report_id;
115 	s32 min;
116 
117 	hsdev = st->common_attributes.hsdev;
118 	switch (mask) {
119 	case IIO_CHAN_INFO_RAW:
120 		hid_sensor_power_state(&st->common_attributes, true);
121 		report_id = st->hinge[chan->scan_index].report_id;
122 		min = st->hinge[chan->scan_index].logical_minimum;
123 		if (report_id < 0) {
124 			hid_sensor_power_state(&st->common_attributes, false);
125 			return -EINVAL;
126 		}
127 
128 		*val = sensor_hub_input_attr_get_raw_value(st->common_attributes.hsdev,
129 							   hsdev->usage,
130 							   hinge_addresses[chan->scan_index],
131 							   report_id,
132 							   SENSOR_HUB_SYNC, min < 0);
133 
134 		hid_sensor_power_state(&st->common_attributes, false);
135 		return IIO_VAL_INT;
136 	case IIO_CHAN_INFO_SCALE:
137 		*val = st->scale_pre_decml;
138 		*val2 = st->scale_post_decml;
139 		return st->scale_precision;
140 	case IIO_CHAN_INFO_OFFSET:
141 		*val = st->value_offset;
142 		return IIO_VAL_INT;
143 	case IIO_CHAN_INFO_SAMP_FREQ:
144 		return hid_sensor_read_samp_freq_value(&st->common_attributes,
145 						       val, val2);
146 	case IIO_CHAN_INFO_HYSTERESIS:
147 		return hid_sensor_read_raw_hyst_value(&st->common_attributes,
148 						      val, val2);
149 	default:
150 		return -EINVAL;
151 	}
152 }
153 
154 /* Channel write_raw handler */
155 static int hinge_write_raw(struct iio_dev *indio_dev,
156 			   struct iio_chan_spec const *chan, int val, int val2,
157 			   long mask)
158 {
159 	struct hinge_state *st = iio_priv(indio_dev);
160 
161 	switch (mask) {
162 	case IIO_CHAN_INFO_SAMP_FREQ:
163 		return hid_sensor_write_samp_freq_value(&st->common_attributes,
164 							val, val2);
165 	case IIO_CHAN_INFO_HYSTERESIS:
166 		return hid_sensor_write_raw_hyst_value(&st->common_attributes,
167 						       val, val2);
168 	default:
169 		return -EINVAL;
170 	}
171 }
172 
173 static int hinge_read_label(struct iio_dev *indio_dev,
174 			    struct iio_chan_spec const *chan, char *label)
175 {
176 	struct hinge_state *st = iio_priv(indio_dev);
177 
178 	return sysfs_emit(label, "%s\n", st->labels[chan->channel]);
179 }
180 
181 static const struct iio_info hinge_info = {
182 	.read_raw = hinge_read_raw,
183 	.write_raw = hinge_write_raw,
184 	.read_label = hinge_read_label,
185 };
186 
187 /*
188  * Callback handler to send event after all samples are received
189  * and captured.
190  */
191 static int hinge_proc_event(struct hid_sensor_hub_device *hsdev,
192 			    unsigned int usage_id, void *priv)
193 {
194 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
195 	struct hinge_state *st = iio_priv(indio_dev);
196 
197 	if (atomic_read(&st->common_attributes.data_ready)) {
198 		if (!st->timestamp)
199 			st->timestamp = iio_get_time_ns(indio_dev);
200 
201 		iio_push_to_buffers_with_timestamp(indio_dev, &st->scan,
202 						   st->timestamp);
203 
204 		st->timestamp = 0;
205 	}
206 	return 0;
207 }
208 
209 /* Capture samples in local storage */
210 static int hinge_capture_sample(struct hid_sensor_hub_device *hsdev,
211 				unsigned int usage_id, size_t raw_len,
212 				char *raw_data, void *priv)
213 {
214 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
215 	struct hinge_state *st = iio_priv(indio_dev);
216 	int offset;
217 
218 	switch (usage_id) {
219 	case HID_USAGE_SENSOR_DATA_FIELD_CUSTOM_VALUE(1):
220 	case HID_USAGE_SENSOR_DATA_FIELD_CUSTOM_VALUE(2):
221 	case HID_USAGE_SENSOR_DATA_FIELD_CUSTOM_VALUE(3):
222 		offset = usage_id - HID_USAGE_SENSOR_DATA_FIELD_CUSTOM_VALUE(1);
223 		st->scan.hinge_val[offset] = *(u32 *)raw_data;
224 		return 0;
225 	case HID_USAGE_SENSOR_TIME_TIMESTAMP:
226 		st->timestamp = hid_sensor_convert_timestamp(&st->common_attributes,
227 							     *(int64_t *)raw_data);
228 		return 0;
229 	default:
230 		return -EINVAL;
231 	}
232 }
233 
234 /* Parse report which is specific to an usage id */
235 static int hinge_parse_report(struct platform_device *pdev,
236 			      struct hid_sensor_hub_device *hsdev,
237 			      struct iio_chan_spec *channels,
238 			      unsigned int usage_id, struct hinge_state *st)
239 {
240 	int ret;
241 	int i;
242 
243 	for (i = 0; i < CHANNEL_SCAN_INDEX_MAX; ++i) {
244 		ret = sensor_hub_input_get_attribute_info(hsdev,
245 							  HID_INPUT_REPORT,
246 							  usage_id,
247 							  hinge_addresses[i],
248 							  &st->hinge[i]);
249 		if (ret < 0)
250 			return ret;
251 
252 		hinge_adjust_channel_realbits(channels, i, st->hinge[i].size);
253 	}
254 
255 	st->scale_precision = hid_sensor_format_scale(HID_USAGE_SENSOR_HINGE,
256 			&st->hinge[CHANNEL_SCAN_INDEX_HINGE_ANGLE],
257 			&st->scale_pre_decml, &st->scale_post_decml);
258 
259 	return ret;
260 }
261 
262 /* Function to initialize the processing for usage id */
263 static int hid_hinge_probe(struct platform_device *pdev)
264 {
265 	struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);
266 	struct hinge_state *st;
267 	struct iio_dev *indio_dev;
268 	int ret;
269 	int i;
270 
271 	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*st));
272 	if (!indio_dev)
273 		return -ENOMEM;
274 
275 	platform_set_drvdata(pdev, indio_dev);
276 
277 	st = iio_priv(indio_dev);
278 	st->common_attributes.hsdev = hsdev;
279 	st->common_attributes.pdev = pdev;
280 	st->indio_dev = indio_dev;
281 	for (i = 0; i < CHANNEL_SCAN_INDEX_MAX; i++)
282 		st->labels[i] = hinge_labels[i];
283 
284 	ret = hid_sensor_parse_common_attributes(hsdev, hsdev->usage,
285 						 &st->common_attributes,
286 						 hinge_sensitivity_addresses,
287 						 ARRAY_SIZE(hinge_sensitivity_addresses));
288 	if (ret) {
289 		dev_err(&pdev->dev, "failed to setup common attributes\n");
290 		return ret;
291 	}
292 
293 	indio_dev->num_channels = ARRAY_SIZE(hinge_channels);
294 	indio_dev->channels = devm_kmemdup(&indio_dev->dev, hinge_channels,
295 					   sizeof(hinge_channels), GFP_KERNEL);
296 	if (!indio_dev->channels)
297 		return -ENOMEM;
298 
299 	ret = hinge_parse_report(pdev, hsdev,
300 				 (struct iio_chan_spec *)indio_dev->channels,
301 				 hsdev->usage, st);
302 	if (ret) {
303 		dev_err(&pdev->dev, "failed to setup attributes\n");
304 		return ret;
305 	}
306 
307 	indio_dev->info = &hinge_info;
308 	indio_dev->name = "hinge";
309 	indio_dev->modes = INDIO_DIRECT_MODE;
310 
311 	atomic_set(&st->common_attributes.data_ready, 0);
312 	ret = hid_sensor_setup_trigger(indio_dev, indio_dev->name,
313 				       &st->common_attributes);
314 	if (ret < 0) {
315 		dev_err(&pdev->dev, "trigger setup failed\n");
316 		return ret;
317 	}
318 
319 	st->callbacks.send_event = hinge_proc_event;
320 	st->callbacks.capture_sample = hinge_capture_sample;
321 	st->callbacks.pdev = pdev;
322 	ret = sensor_hub_register_callback(hsdev, hsdev->usage, &st->callbacks);
323 	if (ret < 0) {
324 		dev_err(&pdev->dev, "callback reg failed\n");
325 		goto error_remove_trigger;
326 	}
327 
328 	ret = iio_device_register(indio_dev);
329 	if (ret) {
330 		dev_err(&pdev->dev, "device register failed\n");
331 		goto error_remove_callback;
332 	}
333 
334 	return ret;
335 
336 error_remove_callback:
337 	sensor_hub_remove_callback(hsdev, hsdev->usage);
338 error_remove_trigger:
339 	hid_sensor_remove_trigger(indio_dev, &st->common_attributes);
340 	return ret;
341 }
342 
343 /* Function to deinitialize the processing for usage id */
344 static void hid_hinge_remove(struct platform_device *pdev)
345 {
346 	struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);
347 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
348 	struct hinge_state *st = iio_priv(indio_dev);
349 
350 	iio_device_unregister(indio_dev);
351 	sensor_hub_remove_callback(hsdev, hsdev->usage);
352 	hid_sensor_remove_trigger(indio_dev, &st->common_attributes);
353 }
354 
355 static const struct platform_device_id hid_hinge_ids[] = {
356 	{
357 		/* Format: HID-SENSOR-INT-usage_id_in_hex_lowercase */
358 		.name = "HID-SENSOR-INT-020b",
359 	},
360 	{ }
361 };
362 MODULE_DEVICE_TABLE(platform, hid_hinge_ids);
363 
364 static struct platform_driver hid_hinge_platform_driver = {
365 	.id_table = hid_hinge_ids,
366 	.driver = {
367 		.name	= KBUILD_MODNAME,
368 		.pm	= &hid_sensor_pm_ops,
369 	},
370 	.probe		= hid_hinge_probe,
371 	.remove		= hid_hinge_remove,
372 };
373 module_platform_driver(hid_hinge_platform_driver);
374 
375 MODULE_DESCRIPTION("HID Sensor INTEL Hinge");
376 MODULE_AUTHOR("Ye Xiang <xiang.ye@intel.com>");
377 MODULE_LICENSE("GPL");
378 MODULE_IMPORT_NS("IIO_HID");
379