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 static const u32 hinge_sensitivity_addresses[] = {
51 	HID_USAGE_SENSOR_DATA_FIELD_CUSTOM_VALUE(1),
52 };
53 
54 /* Channel definitions */
55 static const struct iio_chan_spec hinge_channels[] = {
56 	{
57 		.type = IIO_ANGL,
58 		.indexed = 1,
59 		.channel = 0,
60 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
61 		.info_mask_shared_by_type =
62 			BIT(IIO_CHAN_INFO_OFFSET) | BIT(IIO_CHAN_INFO_SCALE) |
63 			BIT(IIO_CHAN_INFO_SAMP_FREQ) | BIT(IIO_CHAN_INFO_HYSTERESIS),
64 		.scan_index = CHANNEL_SCAN_INDEX_HINGE_ANGLE,
65 		.scan_type = {
66 			.sign = 's',
67 			.storagebits = 32,
68 		},
69 	}, {
70 		.type = IIO_ANGL,
71 		.indexed = 1,
72 		.channel = 1,
73 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
74 		.info_mask_shared_by_type =
75 			BIT(IIO_CHAN_INFO_OFFSET) | BIT(IIO_CHAN_INFO_SCALE) |
76 			BIT(IIO_CHAN_INFO_SAMP_FREQ) | BIT(IIO_CHAN_INFO_HYSTERESIS),
77 		.scan_index = CHANNEL_SCAN_INDEX_SCREEN_ANGLE,
78 		.scan_type = {
79 			.sign = 's',
80 			.storagebits = 32,
81 		},
82 	}, {
83 		.type = IIO_ANGL,
84 		.indexed = 1,
85 		.channel = 2,
86 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
87 		.info_mask_shared_by_type =
88 			BIT(IIO_CHAN_INFO_OFFSET) | BIT(IIO_CHAN_INFO_SCALE) |
89 			BIT(IIO_CHAN_INFO_SAMP_FREQ) | BIT(IIO_CHAN_INFO_HYSTERESIS),
90 		.scan_index = CHANNEL_SCAN_INDEX_KEYBOARD_ANGLE,
91 		.scan_type = {
92 			.sign = 's',
93 			.storagebits = 32,
94 		},
95 	},
96 	IIO_CHAN_SOFT_TIMESTAMP(CHANNEL_SCAN_INDEX_TIMESTAMP)
97 };
98 
99 /* Adjust channel real bits based on report descriptor */
100 static void hinge_adjust_channel_realbits(struct iio_chan_spec *channels,
101 					  int channel, int size)
102 {
103 	channels[channel].scan_type.realbits = size * 8;
104 }
105 
106 /* Channel read_raw handler */
107 static int hinge_read_raw(struct iio_dev *indio_dev,
108 			  struct iio_chan_spec const *chan, int *val, int *val2,
109 			  long mask)
110 {
111 	struct hinge_state *st = iio_priv(indio_dev);
112 	struct hid_sensor_hub_device *hsdev;
113 	int report_id;
114 	s32 min;
115 
116 	hsdev = st->common_attributes.hsdev;
117 	switch (mask) {
118 	case IIO_CHAN_INFO_RAW:
119 		hid_sensor_power_state(&st->common_attributes, true);
120 		report_id = st->hinge[chan->scan_index].report_id;
121 		min = st->hinge[chan->scan_index].logical_minimum;
122 		if (report_id < 0) {
123 			hid_sensor_power_state(&st->common_attributes, false);
124 			return -EINVAL;
125 		}
126 
127 		*val = sensor_hub_input_attr_get_raw_value(st->common_attributes.hsdev,
128 							   hsdev->usage,
129 							   hinge_addresses[chan->scan_index],
130 							   report_id,
131 							   SENSOR_HUB_SYNC, min < 0);
132 
133 		hid_sensor_power_state(&st->common_attributes, false);
134 		return IIO_VAL_INT;
135 	case IIO_CHAN_INFO_SCALE:
136 		*val = st->scale_pre_decml;
137 		*val2 = st->scale_post_decml;
138 		return st->scale_precision;
139 	case IIO_CHAN_INFO_OFFSET:
140 		*val = st->value_offset;
141 		return IIO_VAL_INT;
142 	case IIO_CHAN_INFO_SAMP_FREQ:
143 		return hid_sensor_read_samp_freq_value(&st->common_attributes,
144 						       val, val2);
145 	case IIO_CHAN_INFO_HYSTERESIS:
146 		return hid_sensor_read_raw_hyst_value(&st->common_attributes,
147 						      val, val2);
148 	default:
149 		return -EINVAL;
150 	}
151 }
152 
153 /* Channel write_raw handler */
154 static int hinge_write_raw(struct iio_dev *indio_dev,
155 			   struct iio_chan_spec const *chan, int val, int val2,
156 			   long mask)
157 {
158 	struct hinge_state *st = iio_priv(indio_dev);
159 
160 	switch (mask) {
161 	case IIO_CHAN_INFO_SAMP_FREQ:
162 		return hid_sensor_write_samp_freq_value(&st->common_attributes,
163 							val, val2);
164 	case IIO_CHAN_INFO_HYSTERESIS:
165 		return hid_sensor_write_raw_hyst_value(&st->common_attributes,
166 						       val, val2);
167 	default:
168 		return -EINVAL;
169 	}
170 }
171 
172 static int hinge_read_label(struct iio_dev *indio_dev,
173 			    struct iio_chan_spec const *chan, char *label)
174 {
175 	struct hinge_state *st = iio_priv(indio_dev);
176 
177 	return sprintf(label, "%s\n", st->labels[chan->channel]);
178 }
179 
180 static const struct iio_info hinge_info = {
181 	.read_raw = hinge_read_raw,
182 	.write_raw = hinge_write_raw,
183 	.read_label = hinge_read_label,
184 };
185 
186 /*
187  * Callback handler to send event after all samples are received
188  * and captured.
189  */
190 static int hinge_proc_event(struct hid_sensor_hub_device *hsdev,
191 			    unsigned int usage_id, void *priv)
192 {
193 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
194 	struct hinge_state *st = iio_priv(indio_dev);
195 
196 	if (atomic_read(&st->common_attributes.data_ready)) {
197 		if (!st->timestamp)
198 			st->timestamp = iio_get_time_ns(indio_dev);
199 
200 		iio_push_to_buffers_with_timestamp(indio_dev, &st->scan,
201 						   st->timestamp);
202 
203 		st->timestamp = 0;
204 	}
205 	return 0;
206 }
207 
208 /* Capture samples in local storage */
209 static int hinge_capture_sample(struct hid_sensor_hub_device *hsdev,
210 				unsigned int usage_id, size_t raw_len,
211 				char *raw_data, void *priv)
212 {
213 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
214 	struct hinge_state *st = iio_priv(indio_dev);
215 	int offset;
216 
217 	switch (usage_id) {
218 	case HID_USAGE_SENSOR_DATA_FIELD_CUSTOM_VALUE(1):
219 	case HID_USAGE_SENSOR_DATA_FIELD_CUSTOM_VALUE(2):
220 	case HID_USAGE_SENSOR_DATA_FIELD_CUSTOM_VALUE(3):
221 		offset = usage_id - HID_USAGE_SENSOR_DATA_FIELD_CUSTOM_VALUE(1);
222 		st->scan.hinge_val[offset] = *(u32 *)raw_data;
223 		return 0;
224 	case HID_USAGE_SENSOR_TIME_TIMESTAMP:
225 		st->timestamp = hid_sensor_convert_timestamp(&st->common_attributes,
226 							     *(int64_t *)raw_data);
227 		return 0;
228 	default:
229 		return -EINVAL;
230 	}
231 }
232 
233 /* Parse report which is specific to an usage id */
234 static int hinge_parse_report(struct platform_device *pdev,
235 			      struct hid_sensor_hub_device *hsdev,
236 			      struct iio_chan_spec *channels,
237 			      unsigned int usage_id, struct hinge_state *st)
238 {
239 	int ret;
240 	int i;
241 
242 	for (i = 0; i < CHANNEL_SCAN_INDEX_MAX; ++i) {
243 		ret = sensor_hub_input_get_attribute_info(hsdev,
244 							  HID_INPUT_REPORT,
245 							  usage_id,
246 							  hinge_addresses[i],
247 							  &st->hinge[i]);
248 		if (ret < 0)
249 			return ret;
250 
251 		hinge_adjust_channel_realbits(channels, i, st->hinge[i].size);
252 	}
253 
254 	st->scale_precision = hid_sensor_format_scale(HID_USAGE_SENSOR_HINGE,
255 			&st->hinge[CHANNEL_SCAN_INDEX_HINGE_ANGLE],
256 			&st->scale_pre_decml, &st->scale_post_decml);
257 
258 	return ret;
259 }
260 
261 /* Function to initialize the processing for usage id */
262 static int hid_hinge_probe(struct platform_device *pdev)
263 {
264 	struct hinge_state *st;
265 	struct iio_dev *indio_dev;
266 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
267 	int ret;
268 	int i;
269 
270 	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*st));
271 	if (!indio_dev)
272 		return -ENOMEM;
273 
274 	platform_set_drvdata(pdev, indio_dev);
275 
276 	st = iio_priv(indio_dev);
277 	st->common_attributes.hsdev = hsdev;
278 	st->common_attributes.pdev = pdev;
279 	st->indio_dev = indio_dev;
280 	for (i = 0; i < CHANNEL_SCAN_INDEX_MAX; i++)
281 		st->labels[i] = hinge_labels[i];
282 
283 	ret = hid_sensor_parse_common_attributes(hsdev, hsdev->usage,
284 						 &st->common_attributes,
285 						 hinge_sensitivity_addresses,
286 						 ARRAY_SIZE(hinge_sensitivity_addresses));
287 	if (ret) {
288 		dev_err(&pdev->dev, "failed to setup common attributes\n");
289 		return ret;
290 	}
291 
292 	indio_dev->num_channels = ARRAY_SIZE(hinge_channels);
293 	indio_dev->channels = devm_kmemdup(&indio_dev->dev, hinge_channels,
294 					   sizeof(hinge_channels), GFP_KERNEL);
295 	if (!indio_dev->channels)
296 		return -ENOMEM;
297 
298 	ret = hinge_parse_report(pdev, hsdev,
299 				 (struct iio_chan_spec *)indio_dev->channels,
300 				 hsdev->usage, st);
301 	if (ret) {
302 		dev_err(&pdev->dev, "failed to setup attributes\n");
303 		return ret;
304 	}
305 
306 	indio_dev->dev.parent = &pdev->dev;
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 int hid_hinge_remove(struct platform_device *pdev)
345 {
346 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
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 	return 0;
355 }
356 
357 static const struct platform_device_id hid_hinge_ids[] = {
358 	{
359 		/* Format: HID-SENSOR-INT-usage_id_in_hex_lowercase */
360 		.name = "HID-SENSOR-INT-020b",
361 	},
362 	{ /* sentinel */ }
363 };
364 MODULE_DEVICE_TABLE(platform, hid_hinge_ids);
365 
366 static struct platform_driver hid_hinge_platform_driver = {
367 	.id_table = hid_hinge_ids,
368 	.driver = {
369 		.name	= KBUILD_MODNAME,
370 		.pm	= &hid_sensor_pm_ops,
371 	},
372 	.probe		= hid_hinge_probe,
373 	.remove		= hid_hinge_remove,
374 };
375 module_platform_driver(hid_hinge_platform_driver);
376 
377 MODULE_DESCRIPTION("HID Sensor INTEL Hinge");
378 MODULE_AUTHOR("Ye Xiang <xiang.ye@intel.com>");
379 MODULE_LICENSE("GPL");
380