xref: /linux/drivers/iio/orientation/hid-sensor-rotation.c (revision 3d2c3d2eea9acdbee5b5742d15d021069b49d3f9)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * HID Sensors Driver
4  * Copyright (c) 2014, Intel Corporation.
5  */
6 
7 #include <linux/device.h>
8 #include <linux/platform_device.h>
9 #include <linux/module.h>
10 #include <linux/mod_devicetable.h>
11 #include <linux/hid-sensor-hub.h>
12 #include <linux/iio/iio.h>
13 #include <linux/iio/sysfs.h>
14 #include <linux/iio/buffer.h>
15 #include "../common/hid-sensors/hid-sensor-trigger.h"
16 
17 struct dev_rot_state {
18 	struct hid_sensor_hub_callbacks callbacks;
19 	struct hid_sensor_common common_attributes;
20 	struct hid_sensor_hub_attribute_info quaternion;
21 	struct {
22 		IIO_DECLARE_QUATERNION(s32, sampled_vals);
23 		/*
24 		 * ABI regression avoidance: There are two copies of the same
25 		 * timestamp in case of userspace depending on broken alignment
26 		 * from older kernels.
27 		 */
28 		aligned_s64 timestamp[2];
29 	} scan;
30 	int scale_pre_decml;
31 	int scale_post_decml;
32 	int scale_precision;
33 	int value_offset;
34 	s64 timestamp;
35 };
36 
37 static const u32 rotation_sensitivity_addresses[] = {
38 	HID_USAGE_SENSOR_DATA_ORIENTATION,
39 	HID_USAGE_SENSOR_ORIENT_QUATERNION,
40 };
41 
42 /* Channel definitions */
43 static const struct iio_chan_spec dev_rot_channels[] = {
44 	{
45 		.type = IIO_ROT,
46 		.modified = 1,
47 		.channel2 = IIO_MOD_QUATERNION,
48 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
49 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ) |
50 					BIT(IIO_CHAN_INFO_OFFSET) |
51 					BIT(IIO_CHAN_INFO_SCALE) |
52 					BIT(IIO_CHAN_INFO_HYSTERESIS),
53 		.scan_index = 0
54 	},
55 	IIO_CHAN_SOFT_TIMESTAMP(1)
56 };
57 
58 /* Adjust channel real bits based on report descriptor */
59 static void dev_rot_adjust_channel_bit_mask(struct iio_chan_spec *chan,
60 						int size)
61 {
62 	chan->scan_type.sign = 's';
63 	/* Real storage bits will change based on the report desc. */
64 	chan->scan_type.realbits = size * 8;
65 	/* Maximum size of a sample to capture is u32 */
66 	chan->scan_type.storagebits = sizeof(u32) * 8;
67 	chan->scan_type.repeat = 4;
68 }
69 
70 /* Channel read_raw handler */
71 static int dev_rot_read_raw(struct iio_dev *indio_dev,
72 				struct iio_chan_spec const *chan,
73 				int size, int *vals, int *val_len,
74 				long mask)
75 {
76 	struct dev_rot_state *rot_state = iio_priv(indio_dev);
77 	int ret_type;
78 	int i;
79 
80 	vals[0] = 0;
81 	vals[1] = 0;
82 
83 	switch (mask) {
84 	case IIO_CHAN_INFO_RAW:
85 		if (size >= 4) {
86 			for (i = 0; i < 4; ++i)
87 				vals[i] = rot_state->scan.sampled_vals[i];
88 			ret_type = IIO_VAL_INT_MULTIPLE;
89 			*val_len =  4;
90 		} else
91 			ret_type = -EINVAL;
92 		break;
93 	case IIO_CHAN_INFO_SCALE:
94 		vals[0] = rot_state->scale_pre_decml;
95 		vals[1] = rot_state->scale_post_decml;
96 		return rot_state->scale_precision;
97 
98 	case IIO_CHAN_INFO_OFFSET:
99 		*vals = rot_state->value_offset;
100 		return IIO_VAL_INT;
101 
102 	case IIO_CHAN_INFO_SAMP_FREQ:
103 		ret_type = hid_sensor_read_samp_freq_value(
104 			&rot_state->common_attributes, &vals[0], &vals[1]);
105 		break;
106 	case IIO_CHAN_INFO_HYSTERESIS:
107 		ret_type = hid_sensor_read_raw_hyst_value(
108 			&rot_state->common_attributes, &vals[0], &vals[1]);
109 		break;
110 	default:
111 		ret_type = -EINVAL;
112 		break;
113 	}
114 
115 	return ret_type;
116 }
117 
118 /* Channel write_raw handler */
119 static int dev_rot_write_raw(struct iio_dev *indio_dev,
120 			       struct iio_chan_spec const *chan,
121 			       int val,
122 			       int val2,
123 			       long mask)
124 {
125 	struct dev_rot_state *rot_state = iio_priv(indio_dev);
126 	int ret;
127 
128 	switch (mask) {
129 	case IIO_CHAN_INFO_SAMP_FREQ:
130 		ret = hid_sensor_write_samp_freq_value(
131 				&rot_state->common_attributes, val, val2);
132 		break;
133 	case IIO_CHAN_INFO_HYSTERESIS:
134 		ret = hid_sensor_write_raw_hyst_value(
135 				&rot_state->common_attributes, val, val2);
136 		break;
137 	default:
138 		ret = -EINVAL;
139 	}
140 
141 	return ret;
142 }
143 
144 static const struct iio_info dev_rot_info = {
145 	.read_raw_multi = &dev_rot_read_raw,
146 	.write_raw = &dev_rot_write_raw,
147 };
148 
149 /* Callback handler to send event after all samples are received and captured */
150 static int dev_rot_proc_event(struct hid_sensor_hub_device *hsdev,
151 				unsigned usage_id,
152 				void *priv)
153 {
154 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
155 	struct dev_rot_state *rot_state = iio_priv(indio_dev);
156 
157 	dev_dbg(&indio_dev->dev, "dev_rot_proc_event\n");
158 	if (atomic_read(&rot_state->common_attributes.data_ready)) {
159 		if (!rot_state->timestamp)
160 			rot_state->timestamp = iio_get_time_ns(indio_dev);
161 
162 		/*
163 		 * ABI regression avoidance: IIO previously had an incorrect
164 		 * implementation of iio_push_to_buffers_with_timestamp() that
165 		 * put the timestamp in the last 8 bytes of the buffer, which
166 		 * was incorrect according to the IIO ABI. To avoid breaking
167 		 * userspace that may be depending on this broken behavior, we
168 		 * put the timestamp in both the correct place [0] and the old
169 		 * incorrect place [1].
170 		 */
171 		rot_state->scan.timestamp[0] = rot_state->timestamp;
172 		rot_state->scan.timestamp[1] = rot_state->timestamp;
173 
174 		iio_push_to_buffers(indio_dev, &rot_state->scan);
175 
176 		rot_state->timestamp = 0;
177 	}
178 
179 	return 0;
180 }
181 
182 /* Capture samples in local storage */
183 static int dev_rot_capture_sample(struct hid_sensor_hub_device *hsdev,
184 				unsigned usage_id,
185 				size_t raw_len, char *raw_data,
186 				void *priv)
187 {
188 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
189 	struct dev_rot_state *rot_state = iio_priv(indio_dev);
190 
191 	if (usage_id == HID_USAGE_SENSOR_ORIENT_QUATERNION) {
192 		if (raw_len / 4 == sizeof(s16)) {
193 			rot_state->scan.sampled_vals[0] = ((s16 *)raw_data)[0];
194 			rot_state->scan.sampled_vals[1] = ((s16 *)raw_data)[1];
195 			rot_state->scan.sampled_vals[2] = ((s16 *)raw_data)[2];
196 			rot_state->scan.sampled_vals[3] = ((s16 *)raw_data)[3];
197 		} else {
198 			memcpy(&rot_state->scan.sampled_vals, raw_data,
199 			       sizeof(rot_state->scan.sampled_vals));
200 		}
201 
202 		dev_dbg(&indio_dev->dev, "Recd Quat len:%zu::%zu\n", raw_len,
203 			sizeof(rot_state->scan.sampled_vals));
204 	} else if (usage_id == HID_USAGE_SENSOR_TIME_TIMESTAMP) {
205 		rot_state->timestamp = hid_sensor_convert_timestamp(&rot_state->common_attributes,
206 								    *(s64 *)raw_data);
207 	}
208 
209 	return 0;
210 }
211 
212 /* Parse report which is specific to an usage id*/
213 static int dev_rot_parse_report(struct platform_device *pdev,
214 				struct hid_sensor_hub_device *hsdev,
215 				struct iio_chan_spec *channels,
216 				unsigned usage_id,
217 				struct dev_rot_state *st)
218 {
219 	int ret;
220 
221 	ret = sensor_hub_input_get_attribute_info(hsdev,
222 				HID_INPUT_REPORT,
223 				usage_id,
224 				HID_USAGE_SENSOR_ORIENT_QUATERNION,
225 				&st->quaternion);
226 	if (ret)
227 		return ret;
228 
229 	dev_rot_adjust_channel_bit_mask(&channels[0],
230 		st->quaternion.size / 4);
231 
232 	dev_dbg(&pdev->dev, "dev_rot %x:%x\n", st->quaternion.index,
233 		st->quaternion.report_id);
234 
235 	dev_dbg(&pdev->dev, "dev_rot: attrib size %d\n",
236 				st->quaternion.size);
237 
238 	st->scale_precision = hid_sensor_format_scale(
239 				hsdev->usage,
240 				&st->quaternion,
241 				&st->scale_pre_decml, &st->scale_post_decml);
242 
243 	return 0;
244 }
245 
246 /* Function to initialize the processing for usage id */
247 static int hid_dev_rot_probe(struct platform_device *pdev)
248 {
249 	struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);
250 	int ret;
251 	char *name;
252 	struct iio_dev *indio_dev;
253 	struct dev_rot_state *rot_state;
254 
255 	indio_dev = devm_iio_device_alloc(&pdev->dev,
256 					  sizeof(struct dev_rot_state));
257 	if (indio_dev == NULL)
258 		return -ENOMEM;
259 
260 	platform_set_drvdata(pdev, indio_dev);
261 
262 	rot_state = iio_priv(indio_dev);
263 	rot_state->common_attributes.hsdev = hsdev;
264 	rot_state->common_attributes.pdev = pdev;
265 
266 	switch (hsdev->usage) {
267 	case HID_USAGE_SENSOR_DEVICE_ORIENTATION:
268 		name = "dev_rotation";
269 		break;
270 	case HID_USAGE_SENSOR_RELATIVE_ORIENTATION:
271 		name = "relative_orientation";
272 		break;
273 	case HID_USAGE_SENSOR_GEOMAGNETIC_ORIENTATION:
274 		name = "geomagnetic_orientation";
275 		break;
276 	default:
277 		return -EINVAL;
278 	}
279 
280 	ret = hid_sensor_parse_common_attributes(hsdev,
281 						 hsdev->usage,
282 						 &rot_state->common_attributes,
283 						 rotation_sensitivity_addresses,
284 						 ARRAY_SIZE(rotation_sensitivity_addresses));
285 	if (ret) {
286 		dev_err(&pdev->dev, "failed to setup common attributes\n");
287 		return ret;
288 	}
289 
290 	indio_dev->channels = devm_kmemdup(&pdev->dev, dev_rot_channels,
291 					   sizeof(dev_rot_channels),
292 					   GFP_KERNEL);
293 	if (!indio_dev->channels) {
294 		dev_err(&pdev->dev, "failed to duplicate channels\n");
295 		return -ENOMEM;
296 	}
297 
298 	ret = dev_rot_parse_report(pdev, hsdev,
299 				   (struct iio_chan_spec *)indio_dev->channels,
300 					hsdev->usage, rot_state);
301 	if (ret) {
302 		dev_err(&pdev->dev, "failed to setup attributes\n");
303 		return ret;
304 	}
305 
306 	indio_dev->num_channels = ARRAY_SIZE(dev_rot_channels);
307 	indio_dev->info = &dev_rot_info;
308 	indio_dev->name = name;
309 	indio_dev->modes = INDIO_DIRECT_MODE;
310 
311 	atomic_set(&rot_state->common_attributes.data_ready, 0);
312 
313 	ret = hid_sensor_setup_trigger(indio_dev, name,
314 					&rot_state->common_attributes);
315 	if (ret) {
316 		dev_err(&pdev->dev, "trigger setup failed\n");
317 		return ret;
318 	}
319 
320 	ret = iio_device_register(indio_dev);
321 	if (ret) {
322 		dev_err(&pdev->dev, "device register failed\n");
323 		goto error_remove_trigger;
324 	}
325 
326 	rot_state->callbacks.send_event = dev_rot_proc_event;
327 	rot_state->callbacks.capture_sample = dev_rot_capture_sample;
328 	rot_state->callbacks.pdev = pdev;
329 	ret = sensor_hub_register_callback(hsdev, hsdev->usage,
330 					&rot_state->callbacks);
331 	if (ret) {
332 		dev_err(&pdev->dev, "callback reg failed\n");
333 		goto error_iio_unreg;
334 	}
335 
336 	return 0;
337 
338 error_iio_unreg:
339 	iio_device_unregister(indio_dev);
340 error_remove_trigger:
341 	hid_sensor_remove_trigger(indio_dev, &rot_state->common_attributes);
342 	return ret;
343 }
344 
345 /* Function to deinitialize the processing for usage id */
346 static void hid_dev_rot_remove(struct platform_device *pdev)
347 {
348 	struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);
349 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
350 	struct dev_rot_state *rot_state = iio_priv(indio_dev);
351 
352 	sensor_hub_remove_callback(hsdev, hsdev->usage);
353 	iio_device_unregister(indio_dev);
354 	hid_sensor_remove_trigger(indio_dev, &rot_state->common_attributes);
355 }
356 
357 static const struct platform_device_id hid_dev_rot_ids[] = {
358 	{
359 		/* Format: HID-SENSOR-usage_id_in_hex_lowercase */
360 		.name = "HID-SENSOR-20008a",
361 	},
362 	{
363 		/* Relative orientation(AG) sensor */
364 		.name = "HID-SENSOR-20008e",
365 	},
366 	{
367 		/* Geomagnetic orientation(AM) sensor */
368 		.name = "HID-SENSOR-2000c1",
369 	},
370 	{ }
371 };
372 MODULE_DEVICE_TABLE(platform, hid_dev_rot_ids);
373 
374 static struct platform_driver hid_dev_rot_platform_driver = {
375 	.id_table = hid_dev_rot_ids,
376 	.driver = {
377 		.name	= KBUILD_MODNAME,
378 		.pm     = &hid_sensor_pm_ops,
379 	},
380 	.probe		= hid_dev_rot_probe,
381 	.remove		= hid_dev_rot_remove,
382 };
383 module_platform_driver(hid_dev_rot_platform_driver);
384 
385 MODULE_DESCRIPTION("HID Sensor Device Rotation");
386 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
387 MODULE_LICENSE("GPL");
388 MODULE_IMPORT_NS("IIO_HID");
389