1 /*
2  * HID Sensors Driver
3  * Copyright (c) 2014, Intel Corporation.
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms and conditions of the GNU General Public License,
7  * version 2, as published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12  * more details.
13  */
14 
15 #include <linux/device.h>
16 #include <linux/platform_device.h>
17 #include <linux/module.h>
18 #include <linux/interrupt.h>
19 #include <linux/irq.h>
20 #include <linux/slab.h>
21 #include <linux/hid-sensor-hub.h>
22 #include <linux/iio/iio.h>
23 #include <linux/iio/sysfs.h>
24 #include <linux/iio/buffer.h>
25 #include <linux/iio/trigger_consumer.h>
26 #include <linux/iio/triggered_buffer.h>
27 #include "../common/hid-sensors/hid-sensor-trigger.h"
28 
29 struct dev_rot_state {
30 	struct hid_sensor_hub_callbacks callbacks;
31 	struct hid_sensor_common common_attributes;
32 	struct hid_sensor_hub_attribute_info quaternion;
33 	u32 sampled_vals[4];
34 	int scale_pre_decml;
35 	int scale_post_decml;
36 	int scale_precision;
37 	int value_offset;
38 };
39 
40 /* Channel definitions */
41 static const struct iio_chan_spec dev_rot_channels[] = {
42 	{
43 		.type = IIO_ROT,
44 		.modified = 1,
45 		.channel2 = IIO_MOD_QUATERNION,
46 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
47 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ) |
48 					BIT(IIO_CHAN_INFO_OFFSET) |
49 					BIT(IIO_CHAN_INFO_SCALE) |
50 					BIT(IIO_CHAN_INFO_HYSTERESIS)
51 	}
52 };
53 
54 /* Adjust channel real bits based on report descriptor */
55 static void dev_rot_adjust_channel_bit_mask(struct iio_chan_spec *chan,
56 						int size)
57 {
58 	chan->scan_type.sign = 's';
59 	/* Real storage bits will change based on the report desc. */
60 	chan->scan_type.realbits = size * 8;
61 	/* Maximum size of a sample to capture is u32 */
62 	chan->scan_type.storagebits = sizeof(u32) * 8;
63 	chan->scan_type.repeat = 4;
64 }
65 
66 /* Channel read_raw handler */
67 static int dev_rot_read_raw(struct iio_dev *indio_dev,
68 				struct iio_chan_spec const *chan,
69 				int size, int *vals, int *val_len,
70 				long mask)
71 {
72 	struct dev_rot_state *rot_state = iio_priv(indio_dev);
73 	int ret_type;
74 	int i;
75 
76 	vals[0] = 0;
77 	vals[1] = 0;
78 
79 	switch (mask) {
80 	case IIO_CHAN_INFO_RAW:
81 		if (size >= 4) {
82 			for (i = 0; i < 4; ++i)
83 				vals[i] = rot_state->sampled_vals[i];
84 			ret_type = IIO_VAL_INT_MULTIPLE;
85 			*val_len =  4;
86 		} else
87 			ret_type = -EINVAL;
88 		break;
89 	case IIO_CHAN_INFO_SCALE:
90 		vals[0] = rot_state->scale_pre_decml;
91 		vals[1] = rot_state->scale_post_decml;
92 		return rot_state->scale_precision;
93 
94 	case IIO_CHAN_INFO_OFFSET:
95 		*vals = rot_state->value_offset;
96 		return IIO_VAL_INT;
97 
98 	case IIO_CHAN_INFO_SAMP_FREQ:
99 		ret_type = hid_sensor_read_samp_freq_value(
100 			&rot_state->common_attributes, &vals[0], &vals[1]);
101 		break;
102 	case IIO_CHAN_INFO_HYSTERESIS:
103 		ret_type = hid_sensor_read_raw_hyst_value(
104 			&rot_state->common_attributes, &vals[0], &vals[1]);
105 		break;
106 	default:
107 		ret_type = -EINVAL;
108 		break;
109 	}
110 
111 	return ret_type;
112 }
113 
114 /* Channel write_raw handler */
115 static int dev_rot_write_raw(struct iio_dev *indio_dev,
116 			       struct iio_chan_spec const *chan,
117 			       int val,
118 			       int val2,
119 			       long mask)
120 {
121 	struct dev_rot_state *rot_state = iio_priv(indio_dev);
122 	int ret;
123 
124 	switch (mask) {
125 	case IIO_CHAN_INFO_SAMP_FREQ:
126 		ret = hid_sensor_write_samp_freq_value(
127 				&rot_state->common_attributes, val, val2);
128 		break;
129 	case IIO_CHAN_INFO_HYSTERESIS:
130 		ret = hid_sensor_write_raw_hyst_value(
131 				&rot_state->common_attributes, val, val2);
132 		break;
133 	default:
134 		ret = -EINVAL;
135 	}
136 
137 	return ret;
138 }
139 
140 static const struct iio_info dev_rot_info = {
141 	.read_raw_multi = &dev_rot_read_raw,
142 	.write_raw = &dev_rot_write_raw,
143 };
144 
145 /* Function to push data to buffer */
146 static void hid_sensor_push_data(struct iio_dev *indio_dev, u8 *data, int len)
147 {
148 	dev_dbg(&indio_dev->dev, "hid_sensor_push_data >>\n");
149 	iio_push_to_buffers(indio_dev, (u8 *)data);
150 	dev_dbg(&indio_dev->dev, "hid_sensor_push_data <<\n");
151 
152 }
153 
154 /* Callback handler to send event after all samples are received and captured */
155 static int dev_rot_proc_event(struct hid_sensor_hub_device *hsdev,
156 				unsigned usage_id,
157 				void *priv)
158 {
159 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
160 	struct dev_rot_state *rot_state = iio_priv(indio_dev);
161 
162 	dev_dbg(&indio_dev->dev, "dev_rot_proc_event\n");
163 	if (atomic_read(&rot_state->common_attributes.data_ready))
164 		hid_sensor_push_data(indio_dev,
165 				(u8 *)rot_state->sampled_vals,
166 				sizeof(rot_state->sampled_vals));
167 
168 	return 0;
169 }
170 
171 /* Capture samples in local storage */
172 static int dev_rot_capture_sample(struct hid_sensor_hub_device *hsdev,
173 				unsigned usage_id,
174 				size_t raw_len, char *raw_data,
175 				void *priv)
176 {
177 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
178 	struct dev_rot_state *rot_state = iio_priv(indio_dev);
179 
180 	if (usage_id == HID_USAGE_SENSOR_ORIENT_QUATERNION) {
181 		memcpy(rot_state->sampled_vals, raw_data,
182 					sizeof(rot_state->sampled_vals));
183 		dev_dbg(&indio_dev->dev, "Recd Quat len:%zu::%zu\n", raw_len,
184 					sizeof(rot_state->sampled_vals));
185 	}
186 
187 	return 0;
188 }
189 
190 /* Parse report which is specific to an usage id*/
191 static int dev_rot_parse_report(struct platform_device *pdev,
192 				struct hid_sensor_hub_device *hsdev,
193 				struct iio_chan_spec *channels,
194 				unsigned usage_id,
195 				struct dev_rot_state *st)
196 {
197 	int ret;
198 
199 	ret = sensor_hub_input_get_attribute_info(hsdev,
200 				HID_INPUT_REPORT,
201 				usage_id,
202 				HID_USAGE_SENSOR_ORIENT_QUATERNION,
203 				&st->quaternion);
204 	if (ret)
205 		return ret;
206 
207 	dev_rot_adjust_channel_bit_mask(&channels[0],
208 		st->quaternion.size / 4);
209 
210 	dev_dbg(&pdev->dev, "dev_rot %x:%x\n", st->quaternion.index,
211 		st->quaternion.report_id);
212 
213 	dev_dbg(&pdev->dev, "dev_rot: attrib size %d\n",
214 				st->quaternion.size);
215 
216 	st->scale_precision = hid_sensor_format_scale(
217 				hsdev->usage,
218 				&st->quaternion,
219 				&st->scale_pre_decml, &st->scale_post_decml);
220 
221 	/* Set Sensitivity field ids, when there is no individual modifier */
222 	if (st->common_attributes.sensitivity.index < 0) {
223 		sensor_hub_input_get_attribute_info(hsdev,
224 			HID_FEATURE_REPORT, usage_id,
225 			HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS |
226 			HID_USAGE_SENSOR_DATA_ORIENTATION,
227 			&st->common_attributes.sensitivity);
228 		dev_dbg(&pdev->dev, "Sensitivity index:report %d:%d\n",
229 			st->common_attributes.sensitivity.index,
230 			st->common_attributes.sensitivity.report_id);
231 	}
232 
233 	return 0;
234 }
235 
236 /* Function to initialize the processing for usage id */
237 static int hid_dev_rot_probe(struct platform_device *pdev)
238 {
239 	int ret;
240 	char *name;
241 	struct iio_dev *indio_dev;
242 	struct dev_rot_state *rot_state;
243 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
244 
245 	indio_dev = devm_iio_device_alloc(&pdev->dev,
246 					  sizeof(struct dev_rot_state));
247 	if (indio_dev == NULL)
248 		return -ENOMEM;
249 
250 	platform_set_drvdata(pdev, indio_dev);
251 
252 	rot_state = iio_priv(indio_dev);
253 	rot_state->common_attributes.hsdev = hsdev;
254 	rot_state->common_attributes.pdev = pdev;
255 
256 	switch (hsdev->usage) {
257 	case HID_USAGE_SENSOR_DEVICE_ORIENTATION:
258 		name = "dev_rotation";
259 		break;
260 	case HID_USAGE_SENSOR_RELATIVE_ORIENTATION:
261 		name = "relative_orientation";
262 		break;
263 	case HID_USAGE_SENSOR_GEOMAGNETIC_ORIENTATION:
264 		name = "geomagnetic_orientation";
265 		break;
266 	default:
267 		return -EINVAL;
268 	}
269 
270 	ret = hid_sensor_parse_common_attributes(hsdev, hsdev->usage,
271 				&rot_state->common_attributes);
272 	if (ret) {
273 		dev_err(&pdev->dev, "failed to setup common attributes\n");
274 		return ret;
275 	}
276 
277 	indio_dev->channels = devm_kmemdup(&pdev->dev, dev_rot_channels,
278 					   sizeof(dev_rot_channels),
279 					   GFP_KERNEL);
280 	if (!indio_dev->channels) {
281 		dev_err(&pdev->dev, "failed to duplicate channels\n");
282 		return -ENOMEM;
283 	}
284 
285 	ret = dev_rot_parse_report(pdev, hsdev,
286 				   (struct iio_chan_spec *)indio_dev->channels,
287 					hsdev->usage, rot_state);
288 	if (ret) {
289 		dev_err(&pdev->dev, "failed to setup attributes\n");
290 		return ret;
291 	}
292 
293 	indio_dev->num_channels = ARRAY_SIZE(dev_rot_channels);
294 	indio_dev->dev.parent = &pdev->dev;
295 	indio_dev->info = &dev_rot_info;
296 	indio_dev->name = name;
297 	indio_dev->modes = INDIO_DIRECT_MODE;
298 
299 	ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
300 		NULL, NULL);
301 	if (ret) {
302 		dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
303 		return ret;
304 	}
305 	atomic_set(&rot_state->common_attributes.data_ready, 0);
306 	ret = hid_sensor_setup_trigger(indio_dev, name,
307 					&rot_state->common_attributes);
308 	if (ret) {
309 		dev_err(&pdev->dev, "trigger setup failed\n");
310 		goto error_unreg_buffer_funcs;
311 	}
312 
313 	ret = iio_device_register(indio_dev);
314 	if (ret) {
315 		dev_err(&pdev->dev, "device register failed\n");
316 		goto error_remove_trigger;
317 	}
318 
319 	rot_state->callbacks.send_event = dev_rot_proc_event;
320 	rot_state->callbacks.capture_sample = dev_rot_capture_sample;
321 	rot_state->callbacks.pdev = pdev;
322 	ret = sensor_hub_register_callback(hsdev, hsdev->usage,
323 					&rot_state->callbacks);
324 	if (ret) {
325 		dev_err(&pdev->dev, "callback reg failed\n");
326 		goto error_iio_unreg;
327 	}
328 
329 	return 0;
330 
331 error_iio_unreg:
332 	iio_device_unregister(indio_dev);
333 error_remove_trigger:
334 	hid_sensor_remove_trigger(&rot_state->common_attributes);
335 error_unreg_buffer_funcs:
336 	iio_triggered_buffer_cleanup(indio_dev);
337 	return ret;
338 }
339 
340 /* Function to deinitialize the processing for usage id */
341 static int hid_dev_rot_remove(struct platform_device *pdev)
342 {
343 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
344 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
345 	struct dev_rot_state *rot_state = iio_priv(indio_dev);
346 
347 	sensor_hub_remove_callback(hsdev, hsdev->usage);
348 	iio_device_unregister(indio_dev);
349 	hid_sensor_remove_trigger(&rot_state->common_attributes);
350 	iio_triggered_buffer_cleanup(indio_dev);
351 
352 	return 0;
353 }
354 
355 static const struct platform_device_id hid_dev_rot_ids[] = {
356 	{
357 		/* Format: HID-SENSOR-usage_id_in_hex_lowercase */
358 		.name = "HID-SENSOR-20008a",
359 	},
360 	{
361 		/* Relative orientation(AG) sensor */
362 		.name = "HID-SENSOR-20008e",
363 	},
364 	{
365 		/* Geomagnetic orientation(AM) sensor */
366 		.name = "HID-SENSOR-2000c1",
367 	},
368 	{ /* sentinel */ }
369 };
370 MODULE_DEVICE_TABLE(platform, hid_dev_rot_ids);
371 
372 static struct platform_driver hid_dev_rot_platform_driver = {
373 	.id_table = hid_dev_rot_ids,
374 	.driver = {
375 		.name	= KBUILD_MODNAME,
376 		.pm     = &hid_sensor_pm_ops,
377 	},
378 	.probe		= hid_dev_rot_probe,
379 	.remove		= hid_dev_rot_remove,
380 };
381 module_platform_driver(hid_dev_rot_platform_driver);
382 
383 MODULE_DESCRIPTION("HID Sensor Device Rotation");
384 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
385 MODULE_LICENSE("GPL");
386