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 
11 #include "../common/hid-sensors/hid-sensor-trigger.h"
12 
13 enum hinge_channel {
14 	CHANNEL_SCAN_INDEX_HINGE_ANGLE,
15 	CHANNEL_SCAN_INDEX_SCREEN_ANGLE,
16 	CHANNEL_SCAN_INDEX_KEYBOARD_ANGLE,
17 	CHANNEL_SCAN_INDEX_MAX,
18 };
19 
20 #define CHANNEL_SCAN_INDEX_TIMESTAMP CHANNEL_SCAN_INDEX_MAX
21 
22 static const u32 hinge_addresses[CHANNEL_SCAN_INDEX_MAX] = {
23 	HID_USAGE_SENSOR_DATA_FIELD_CUSTOM_VALUE(1),
24 	HID_USAGE_SENSOR_DATA_FIELD_CUSTOM_VALUE(2),
25 	HID_USAGE_SENSOR_DATA_FIELD_CUSTOM_VALUE(3)
26 };
27 
28 static const char *const hinge_labels[CHANNEL_SCAN_INDEX_MAX] = { "hinge",
29 								  "screen",
30 								  "keyboard" };
31 
32 struct hinge_state {
33 	struct iio_dev *indio_dev;
34 	struct hid_sensor_hub_attribute_info hinge[CHANNEL_SCAN_INDEX_MAX];
35 	struct hid_sensor_hub_callbacks callbacks;
36 	struct hid_sensor_common common_attributes;
37 	const char *labels[CHANNEL_SCAN_INDEX_MAX];
38 	struct {
39 		u32 hinge_val[3];
40 		u64 timestamp __aligned(8);
41 	} scan;
42 
43 	int scale_pre_decml;
44 	int scale_post_decml;
45 	int scale_precision;
46 	int value_offset;
47 	u64 timestamp;
48 };
49 
50 /* Channel definitions */
51 static const struct iio_chan_spec hinge_channels[] = {
52 	{
53 		.type = IIO_ANGL,
54 		.indexed = 1,
55 		.channel = 0,
56 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
57 		.info_mask_shared_by_type =
58 			BIT(IIO_CHAN_INFO_OFFSET) | BIT(IIO_CHAN_INFO_SCALE) |
59 			BIT(IIO_CHAN_INFO_SAMP_FREQ) | BIT(IIO_CHAN_INFO_HYSTERESIS),
60 		.scan_index = CHANNEL_SCAN_INDEX_HINGE_ANGLE,
61 		.scan_type = {
62 			.sign = 's',
63 			.storagebits = 32,
64 		},
65 	}, {
66 		.type = IIO_ANGL,
67 		.indexed = 1,
68 		.channel = 1,
69 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
70 		.info_mask_shared_by_type =
71 			BIT(IIO_CHAN_INFO_OFFSET) | BIT(IIO_CHAN_INFO_SCALE) |
72 			BIT(IIO_CHAN_INFO_SAMP_FREQ) | BIT(IIO_CHAN_INFO_HYSTERESIS),
73 		.scan_index = CHANNEL_SCAN_INDEX_SCREEN_ANGLE,
74 		.scan_type = {
75 			.sign = 's',
76 			.storagebits = 32,
77 		},
78 	}, {
79 		.type = IIO_ANGL,
80 		.indexed = 1,
81 		.channel = 2,
82 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
83 		.info_mask_shared_by_type =
84 			BIT(IIO_CHAN_INFO_OFFSET) | BIT(IIO_CHAN_INFO_SCALE) |
85 			BIT(IIO_CHAN_INFO_SAMP_FREQ) | BIT(IIO_CHAN_INFO_HYSTERESIS),
86 		.scan_index = CHANNEL_SCAN_INDEX_KEYBOARD_ANGLE,
87 		.scan_type = {
88 			.sign = 's',
89 			.storagebits = 32,
90 		},
91 	},
92 	IIO_CHAN_SOFT_TIMESTAMP(CHANNEL_SCAN_INDEX_TIMESTAMP)
93 };
94 
95 /* Adjust channel real bits based on report descriptor */
96 static void hinge_adjust_channel_realbits(struct iio_chan_spec *channels,
97 					  int channel, int size)
98 {
99 	channels[channel].scan_type.realbits = size * 8;
100 }
101 
102 /* Channel read_raw handler */
103 static int hinge_read_raw(struct iio_dev *indio_dev,
104 			  struct iio_chan_spec const *chan, int *val, int *val2,
105 			  long mask)
106 {
107 	struct hinge_state *st = iio_priv(indio_dev);
108 	struct hid_sensor_hub_device *hsdev;
109 	int report_id;
110 	s32 min;
111 
112 	hsdev = st->common_attributes.hsdev;
113 	switch (mask) {
114 	case IIO_CHAN_INFO_RAW:
115 		hid_sensor_power_state(&st->common_attributes, true);
116 		report_id = st->hinge[chan->scan_index].report_id;
117 		min = st->hinge[chan->scan_index].logical_minimum;
118 		if (report_id < 0) {
119 			hid_sensor_power_state(&st->common_attributes, false);
120 			return -EINVAL;
121 		}
122 
123 		*val = sensor_hub_input_attr_get_raw_value(st->common_attributes.hsdev,
124 							   hsdev->usage,
125 							   hinge_addresses[chan->scan_index],
126 							   report_id,
127 							   SENSOR_HUB_SYNC, min < 0);
128 
129 		hid_sensor_power_state(&st->common_attributes, false);
130 		return IIO_VAL_INT;
131 	case IIO_CHAN_INFO_SCALE:
132 		*val = st->scale_pre_decml;
133 		*val2 = st->scale_post_decml;
134 		return st->scale_precision;
135 	case IIO_CHAN_INFO_OFFSET:
136 		*val = st->value_offset;
137 		return IIO_VAL_INT;
138 	case IIO_CHAN_INFO_SAMP_FREQ:
139 		return hid_sensor_read_samp_freq_value(&st->common_attributes,
140 						       val, val2);
141 	case IIO_CHAN_INFO_HYSTERESIS:
142 		return hid_sensor_read_raw_hyst_value(&st->common_attributes,
143 						      val, val2);
144 	default:
145 		return -EINVAL;
146 	}
147 }
148 
149 /* Channel write_raw handler */
150 static int hinge_write_raw(struct iio_dev *indio_dev,
151 			   struct iio_chan_spec const *chan, int val, int val2,
152 			   long mask)
153 {
154 	struct hinge_state *st = iio_priv(indio_dev);
155 
156 	switch (mask) {
157 	case IIO_CHAN_INFO_SAMP_FREQ:
158 		return hid_sensor_write_samp_freq_value(&st->common_attributes,
159 							val, val2);
160 	case IIO_CHAN_INFO_HYSTERESIS:
161 		return hid_sensor_write_raw_hyst_value(&st->common_attributes,
162 						       val, val2);
163 	default:
164 		return -EINVAL;
165 	}
166 }
167 
168 static int hinge_read_label(struct iio_dev *indio_dev,
169 			    struct iio_chan_spec const *chan, char *label)
170 {
171 	struct hinge_state *st = iio_priv(indio_dev);
172 
173 	return sprintf(label, "%s\n", st->labels[chan->channel]);
174 }
175 
176 static const struct iio_info hinge_info = {
177 	.read_raw = hinge_read_raw,
178 	.write_raw = hinge_write_raw,
179 	.read_label = hinge_read_label,
180 };
181 
182 /*
183  * Callback handler to send event after all samples are received
184  * and captured.
185  */
186 static int hinge_proc_event(struct hid_sensor_hub_device *hsdev,
187 			    unsigned int usage_id, void *priv)
188 {
189 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
190 	struct hinge_state *st = iio_priv(indio_dev);
191 
192 	if (atomic_read(&st->common_attributes.data_ready)) {
193 		if (!st->timestamp)
194 			st->timestamp = iio_get_time_ns(indio_dev);
195 
196 		iio_push_to_buffers_with_timestamp(indio_dev, &st->scan,
197 						   st->timestamp);
198 
199 		st->timestamp = 0;
200 	}
201 	return 0;
202 }
203 
204 /* Capture samples in local storage */
205 static int hinge_capture_sample(struct hid_sensor_hub_device *hsdev,
206 				unsigned int usage_id, size_t raw_len,
207 				char *raw_data, void *priv)
208 {
209 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
210 	struct hinge_state *st = iio_priv(indio_dev);
211 	int offset;
212 
213 	switch (usage_id) {
214 	case HID_USAGE_SENSOR_DATA_FIELD_CUSTOM_VALUE(1):
215 	case HID_USAGE_SENSOR_DATA_FIELD_CUSTOM_VALUE(2):
216 	case HID_USAGE_SENSOR_DATA_FIELD_CUSTOM_VALUE(3):
217 		offset = usage_id - HID_USAGE_SENSOR_DATA_FIELD_CUSTOM_VALUE(1);
218 		st->scan.hinge_val[offset] = *(u32 *)raw_data;
219 		return 0;
220 	case HID_USAGE_SENSOR_TIME_TIMESTAMP:
221 		st->timestamp = hid_sensor_convert_timestamp(&st->common_attributes,
222 							     *(int64_t *)raw_data);
223 		return 0;
224 	default:
225 		return -EINVAL;
226 	}
227 }
228 
229 /* Parse report which is specific to an usage id */
230 static int hinge_parse_report(struct platform_device *pdev,
231 			      struct hid_sensor_hub_device *hsdev,
232 			      struct iio_chan_spec *channels,
233 			      unsigned int usage_id, struct hinge_state *st)
234 {
235 	int ret;
236 	int i;
237 
238 	for (i = 0; i < CHANNEL_SCAN_INDEX_MAX; ++i) {
239 		ret = sensor_hub_input_get_attribute_info(hsdev,
240 							  HID_INPUT_REPORT,
241 							  usage_id,
242 							  hinge_addresses[i],
243 							  &st->hinge[i]);
244 		if (ret < 0)
245 			return ret;
246 
247 		hinge_adjust_channel_realbits(channels, i, st->hinge[i].size);
248 	}
249 
250 	st->scale_precision = hid_sensor_format_scale(HID_USAGE_SENSOR_HINGE,
251 			&st->hinge[CHANNEL_SCAN_INDEX_HINGE_ANGLE],
252 			&st->scale_pre_decml, &st->scale_post_decml);
253 
254 	/* Set Sensitivity field ids, when there is no individual modifier */
255 	if (st->common_attributes.sensitivity.index < 0) {
256 		sensor_hub_input_get_attribute_info(hsdev,
257 				HID_FEATURE_REPORT, usage_id,
258 				HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS |
259 					HID_USAGE_SENSOR_DATA_FIELD_CUSTOM_VALUE(1),
260 				&st->common_attributes.sensitivity);
261 		dev_dbg(&pdev->dev, "Sensitivity index:report %d:%d\n",
262 			st->common_attributes.sensitivity.index,
263 			st->common_attributes.sensitivity.report_id);
264 	}
265 
266 	return ret;
267 }
268 
269 /* Function to initialize the processing for usage id */
270 static int hid_hinge_probe(struct platform_device *pdev)
271 {
272 	struct hinge_state *st;
273 	struct iio_dev *indio_dev;
274 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
275 	int ret;
276 	int i;
277 
278 	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*st));
279 	if (!indio_dev)
280 		return -ENOMEM;
281 
282 	platform_set_drvdata(pdev, indio_dev);
283 
284 	st = iio_priv(indio_dev);
285 	st->common_attributes.hsdev = hsdev;
286 	st->common_attributes.pdev = pdev;
287 	st->indio_dev = indio_dev;
288 	for (i = 0; i < CHANNEL_SCAN_INDEX_MAX; i++)
289 		st->labels[i] = hinge_labels[i];
290 
291 	ret = hid_sensor_parse_common_attributes(hsdev, hsdev->usage,
292 						 &st->common_attributes);
293 	if (ret) {
294 		dev_err(&pdev->dev, "failed to setup common attributes\n");
295 		return ret;
296 	}
297 
298 	indio_dev->num_channels = ARRAY_SIZE(hinge_channels);
299 	indio_dev->channels = devm_kmemdup(&indio_dev->dev, hinge_channels,
300 					   sizeof(hinge_channels), GFP_KERNEL);
301 	if (!indio_dev->channels)
302 		return -ENOMEM;
303 
304 	ret = hinge_parse_report(pdev, hsdev,
305 				 (struct iio_chan_spec *)indio_dev->channels,
306 				 hsdev->usage, st);
307 	if (ret) {
308 		dev_err(&pdev->dev, "failed to setup attributes\n");
309 		return ret;
310 	}
311 
312 	indio_dev->dev.parent = &pdev->dev;
313 	indio_dev->info = &hinge_info;
314 	indio_dev->name = "hinge";
315 	indio_dev->modes = INDIO_DIRECT_MODE;
316 
317 	atomic_set(&st->common_attributes.data_ready, 0);
318 	ret = hid_sensor_setup_trigger(indio_dev, indio_dev->name,
319 				       &st->common_attributes);
320 	if (ret < 0) {
321 		dev_err(&pdev->dev, "trigger setup failed\n");
322 		return ret;
323 	}
324 
325 	st->callbacks.send_event = hinge_proc_event;
326 	st->callbacks.capture_sample = hinge_capture_sample;
327 	st->callbacks.pdev = pdev;
328 	ret = sensor_hub_register_callback(hsdev, hsdev->usage, &st->callbacks);
329 	if (ret < 0) {
330 		dev_err(&pdev->dev, "callback reg failed\n");
331 		goto error_remove_trigger;
332 	}
333 
334 	ret = iio_device_register(indio_dev);
335 	if (ret) {
336 		dev_err(&pdev->dev, "device register failed\n");
337 		goto error_remove_callback;
338 	}
339 
340 	return ret;
341 
342 error_remove_callback:
343 	sensor_hub_remove_callback(hsdev, hsdev->usage);
344 error_remove_trigger:
345 	hid_sensor_remove_trigger(indio_dev, &st->common_attributes);
346 	return ret;
347 }
348 
349 /* Function to deinitialize the processing for usage id */
350 static int hid_hinge_remove(struct platform_device *pdev)
351 {
352 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
353 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
354 	struct hinge_state *st = iio_priv(indio_dev);
355 
356 	iio_device_unregister(indio_dev);
357 	sensor_hub_remove_callback(hsdev, hsdev->usage);
358 	hid_sensor_remove_trigger(indio_dev, &st->common_attributes);
359 
360 	return 0;
361 }
362 
363 static const struct platform_device_id hid_hinge_ids[] = {
364 	{
365 		/* Format: HID-SENSOR-INT-usage_id_in_hex_lowercase */
366 		.name = "HID-SENSOR-INT-020b",
367 	},
368 	{ /* sentinel */ }
369 };
370 MODULE_DEVICE_TABLE(platform, hid_hinge_ids);
371 
372 static struct platform_driver hid_hinge_platform_driver = {
373 	.id_table = hid_hinge_ids,
374 	.driver = {
375 		.name	= KBUILD_MODNAME,
376 		.pm	= &hid_sensor_pm_ops,
377 	},
378 	.probe		= hid_hinge_probe,
379 	.remove		= hid_hinge_remove,
380 };
381 module_platform_driver(hid_hinge_platform_driver);
382 
383 MODULE_DESCRIPTION("HID Sensor INTEL Hinge");
384 MODULE_AUTHOR("Ye Xiang <xiang.ye@intel.com>");
385 MODULE_LICENSE("GPL");
386