1 /*
2  * HID Sensors Driver
3  * Copyright (c) 2012, 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  * You should have received a copy of the GNU General Public License along with
15  * this program; if not, write to the Free Software Foundation, Inc.,
16  * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
17  *
18  */
19 #include <linux/device.h>
20 #include <linux/platform_device.h>
21 #include <linux/module.h>
22 #include <linux/interrupt.h>
23 #include <linux/irq.h>
24 #include <linux/slab.h>
25 #include <linux/hid-sensor-hub.h>
26 #include <linux/iio/iio.h>
27 #include <linux/iio/sysfs.h>
28 #include <linux/iio/buffer.h>
29 #include <linux/iio/trigger_consumer.h>
30 #include <linux/iio/triggered_buffer.h>
31 #include "../common/hid-sensors/hid-sensor-trigger.h"
32 
33 enum magn_3d_channel {
34 	CHANNEL_SCAN_INDEX_X,
35 	CHANNEL_SCAN_INDEX_Y,
36 	CHANNEL_SCAN_INDEX_Z,
37 	MAGN_3D_CHANNEL_MAX,
38 };
39 
40 struct magn_3d_state {
41 	struct hid_sensor_hub_callbacks callbacks;
42 	struct hid_sensor_common common_attributes;
43 	struct hid_sensor_hub_attribute_info magn[MAGN_3D_CHANNEL_MAX];
44 	u32 magn_val[MAGN_3D_CHANNEL_MAX];
45 };
46 
47 static const u32 magn_3d_addresses[MAGN_3D_CHANNEL_MAX] = {
48 	HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_X_AXIS,
49 	HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_Y_AXIS,
50 	HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_Z_AXIS
51 };
52 
53 /* Channel definitions */
54 static const struct iio_chan_spec magn_3d_channels[] = {
55 	{
56 		.type = IIO_MAGN,
57 		.modified = 1,
58 		.channel2 = IIO_MOD_X,
59 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
60 		BIT(IIO_CHAN_INFO_SCALE) |
61 		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
62 		BIT(IIO_CHAN_INFO_HYSTERESIS),
63 		.scan_index = CHANNEL_SCAN_INDEX_X,
64 	}, {
65 		.type = IIO_MAGN,
66 		.modified = 1,
67 		.channel2 = IIO_MOD_Y,
68 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
69 		BIT(IIO_CHAN_INFO_SCALE) |
70 		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
71 		BIT(IIO_CHAN_INFO_HYSTERESIS),
72 		.scan_index = CHANNEL_SCAN_INDEX_Y,
73 	}, {
74 		.type = IIO_MAGN,
75 		.modified = 1,
76 		.channel2 = IIO_MOD_Z,
77 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
78 		BIT(IIO_CHAN_INFO_SCALE) |
79 		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
80 		BIT(IIO_CHAN_INFO_HYSTERESIS),
81 		.scan_index = CHANNEL_SCAN_INDEX_Z,
82 	}
83 };
84 
85 /* Adjust channel real bits based on report descriptor */
86 static void magn_3d_adjust_channel_bit_mask(struct iio_chan_spec *channels,
87 						int channel, int size)
88 {
89 	channels[channel].scan_type.sign = 's';
90 	/* Real storage bits will change based on the report desc. */
91 	channels[channel].scan_type.realbits = size * 8;
92 	/* Maximum size of a sample to capture is u32 */
93 	channels[channel].scan_type.storagebits = sizeof(u32) * 8;
94 }
95 
96 /* Channel read_raw handler */
97 static int magn_3d_read_raw(struct iio_dev *indio_dev,
98 			      struct iio_chan_spec const *chan,
99 			      int *val, int *val2,
100 			      long mask)
101 {
102 	struct magn_3d_state *magn_state = iio_priv(indio_dev);
103 	int report_id = -1;
104 	u32 address;
105 	int ret;
106 	int ret_type;
107 
108 	*val = 0;
109 	*val2 = 0;
110 	switch (mask) {
111 	case 0:
112 		report_id =
113 			magn_state->magn[chan->scan_index].report_id;
114 		address = magn_3d_addresses[chan->scan_index];
115 		if (report_id >= 0)
116 			*val = sensor_hub_input_attr_get_raw_value(
117 				magn_state->common_attributes.hsdev,
118 				HID_USAGE_SENSOR_COMPASS_3D, address,
119 				report_id);
120 		else {
121 			*val = 0;
122 			return -EINVAL;
123 		}
124 		ret_type = IIO_VAL_INT;
125 		break;
126 	case IIO_CHAN_INFO_SCALE:
127 		*val = magn_state->magn[CHANNEL_SCAN_INDEX_X].units;
128 		ret_type = IIO_VAL_INT;
129 		break;
130 	case IIO_CHAN_INFO_OFFSET:
131 		*val = hid_sensor_convert_exponent(
132 			magn_state->magn[CHANNEL_SCAN_INDEX_X].unit_expo);
133 		ret_type = IIO_VAL_INT;
134 		break;
135 	case IIO_CHAN_INFO_SAMP_FREQ:
136 		ret = hid_sensor_read_samp_freq_value(
137 			&magn_state->common_attributes, val, val2);
138 		ret_type = IIO_VAL_INT_PLUS_MICRO;
139 		break;
140 	case IIO_CHAN_INFO_HYSTERESIS:
141 		ret = hid_sensor_read_raw_hyst_value(
142 			&magn_state->common_attributes, val, val2);
143 		ret_type = IIO_VAL_INT_PLUS_MICRO;
144 		break;
145 	default:
146 		ret_type = -EINVAL;
147 		break;
148 	}
149 
150 	return ret_type;
151 }
152 
153 /* Channel write_raw handler */
154 static int magn_3d_write_raw(struct iio_dev *indio_dev,
155 			       struct iio_chan_spec const *chan,
156 			       int val,
157 			       int val2,
158 			       long mask)
159 {
160 	struct magn_3d_state *magn_state = iio_priv(indio_dev);
161 	int ret = 0;
162 
163 	switch (mask) {
164 	case IIO_CHAN_INFO_SAMP_FREQ:
165 		ret = hid_sensor_write_samp_freq_value(
166 				&magn_state->common_attributes, val, val2);
167 		break;
168 	case IIO_CHAN_INFO_HYSTERESIS:
169 		ret = hid_sensor_write_raw_hyst_value(
170 				&magn_state->common_attributes, val, val2);
171 		break;
172 	default:
173 		ret = -EINVAL;
174 	}
175 
176 	return ret;
177 }
178 
179 static const struct iio_info magn_3d_info = {
180 	.driver_module = THIS_MODULE,
181 	.read_raw = &magn_3d_read_raw,
182 	.write_raw = &magn_3d_write_raw,
183 };
184 
185 /* Function to push data to buffer */
186 static void hid_sensor_push_data(struct iio_dev *indio_dev, u8 *data, int len)
187 {
188 	dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n");
189 	iio_push_to_buffers(indio_dev, (u8 *)data);
190 }
191 
192 /* Callback handler to send event after all samples are received and captured */
193 static int magn_3d_proc_event(struct hid_sensor_hub_device *hsdev,
194 				unsigned usage_id,
195 				void *priv)
196 {
197 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
198 	struct magn_3d_state *magn_state = iio_priv(indio_dev);
199 
200 	dev_dbg(&indio_dev->dev, "magn_3d_proc_event [%d]\n",
201 				magn_state->common_attributes.data_ready);
202 	if (magn_state->common_attributes.data_ready)
203 		hid_sensor_push_data(indio_dev,
204 				(u8 *)magn_state->magn_val,
205 				sizeof(magn_state->magn_val));
206 
207 	return 0;
208 }
209 
210 /* Capture samples in local storage */
211 static int magn_3d_capture_sample(struct hid_sensor_hub_device *hsdev,
212 				unsigned usage_id,
213 				size_t raw_len, char *raw_data,
214 				void *priv)
215 {
216 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
217 	struct magn_3d_state *magn_state = iio_priv(indio_dev);
218 	int offset;
219 	int ret = -EINVAL;
220 
221 	switch (usage_id) {
222 	case HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_X_AXIS:
223 	case HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_Y_AXIS:
224 	case HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_Z_AXIS:
225 		offset = usage_id - HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_X_AXIS;
226 		magn_state->magn_val[CHANNEL_SCAN_INDEX_X + offset] =
227 						*(u32 *)raw_data;
228 		ret = 0;
229 	break;
230 	default:
231 		break;
232 	}
233 
234 	return ret;
235 }
236 
237 /* Parse report which is specific to an usage id*/
238 static int magn_3d_parse_report(struct platform_device *pdev,
239 				struct hid_sensor_hub_device *hsdev,
240 				struct iio_chan_spec *channels,
241 				unsigned usage_id,
242 				struct magn_3d_state *st)
243 {
244 	int ret;
245 	int i;
246 
247 	for (i = 0; i <= CHANNEL_SCAN_INDEX_Z; ++i) {
248 		ret = sensor_hub_input_get_attribute_info(hsdev,
249 				HID_INPUT_REPORT,
250 				usage_id,
251 				HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_X_AXIS + i,
252 				&st->magn[CHANNEL_SCAN_INDEX_X + i]);
253 		if (ret < 0)
254 			break;
255 		magn_3d_adjust_channel_bit_mask(channels,
256 				CHANNEL_SCAN_INDEX_X + i,
257 				st->magn[CHANNEL_SCAN_INDEX_X + i].size);
258 	}
259 	dev_dbg(&pdev->dev, "magn_3d %x:%x, %x:%x, %x:%x\n",
260 			st->magn[0].index,
261 			st->magn[0].report_id,
262 			st->magn[1].index, st->magn[1].report_id,
263 			st->magn[2].index, st->magn[2].report_id);
264 
265 	return ret;
266 }
267 
268 /* Function to initialize the processing for usage id */
269 static int hid_magn_3d_probe(struct platform_device *pdev)
270 {
271 	int ret = 0;
272 	static char *name = "magn_3d";
273 	struct iio_dev *indio_dev;
274 	struct magn_3d_state *magn_state;
275 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
276 	struct iio_chan_spec *channels;
277 
278 	indio_dev = devm_iio_device_alloc(&pdev->dev,
279 					  sizeof(struct magn_3d_state));
280 	if (indio_dev == NULL)
281 		return -ENOMEM;
282 
283 	platform_set_drvdata(pdev, indio_dev);
284 
285 	magn_state = iio_priv(indio_dev);
286 	magn_state->common_attributes.hsdev = hsdev;
287 	magn_state->common_attributes.pdev = pdev;
288 
289 	ret = hid_sensor_parse_common_attributes(hsdev,
290 				HID_USAGE_SENSOR_COMPASS_3D,
291 				&magn_state->common_attributes);
292 	if (ret) {
293 		dev_err(&pdev->dev, "failed to setup common attributes\n");
294 		return ret;
295 	}
296 
297 	channels = kmemdup(magn_3d_channels, sizeof(magn_3d_channels),
298 			   GFP_KERNEL);
299 	if (!channels) {
300 		dev_err(&pdev->dev, "failed to duplicate channels\n");
301 		return -ENOMEM;
302 	}
303 
304 	ret = magn_3d_parse_report(pdev, hsdev, channels,
305 				HID_USAGE_SENSOR_COMPASS_3D, magn_state);
306 	if (ret) {
307 		dev_err(&pdev->dev, "failed to setup attributes\n");
308 		goto error_free_dev_mem;
309 	}
310 
311 	indio_dev->channels = channels;
312 	indio_dev->num_channels = ARRAY_SIZE(magn_3d_channels);
313 	indio_dev->dev.parent = &pdev->dev;
314 	indio_dev->info = &magn_3d_info;
315 	indio_dev->name = name;
316 	indio_dev->modes = INDIO_DIRECT_MODE;
317 
318 	ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
319 		NULL, NULL);
320 	if (ret) {
321 		dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
322 		goto error_free_dev_mem;
323 	}
324 	magn_state->common_attributes.data_ready = false;
325 	ret = hid_sensor_setup_trigger(indio_dev, name,
326 					&magn_state->common_attributes);
327 	if (ret < 0) {
328 		dev_err(&pdev->dev, "trigger setup failed\n");
329 		goto error_unreg_buffer_funcs;
330 	}
331 
332 	ret = iio_device_register(indio_dev);
333 	if (ret) {
334 		dev_err(&pdev->dev, "device register failed\n");
335 		goto error_remove_trigger;
336 	}
337 
338 	magn_state->callbacks.send_event = magn_3d_proc_event;
339 	magn_state->callbacks.capture_sample = magn_3d_capture_sample;
340 	magn_state->callbacks.pdev = pdev;
341 	ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_COMPASS_3D,
342 					&magn_state->callbacks);
343 	if (ret < 0) {
344 		dev_err(&pdev->dev, "callback reg failed\n");
345 		goto error_iio_unreg;
346 	}
347 
348 	return ret;
349 
350 error_iio_unreg:
351 	iio_device_unregister(indio_dev);
352 error_remove_trigger:
353 	hid_sensor_remove_trigger(indio_dev);
354 error_unreg_buffer_funcs:
355 	iio_triggered_buffer_cleanup(indio_dev);
356 error_free_dev_mem:
357 	kfree(indio_dev->channels);
358 	return ret;
359 }
360 
361 /* Function to deinitialize the processing for usage id */
362 static int hid_magn_3d_remove(struct platform_device *pdev)
363 {
364 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
365 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
366 
367 	sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_COMPASS_3D);
368 	iio_device_unregister(indio_dev);
369 	hid_sensor_remove_trigger(indio_dev);
370 	iio_triggered_buffer_cleanup(indio_dev);
371 	kfree(indio_dev->channels);
372 
373 	return 0;
374 }
375 
376 static struct platform_device_id hid_magn_3d_ids[] = {
377 	{
378 		/* Format: HID-SENSOR-usage_id_in_hex_lowercase */
379 		.name = "HID-SENSOR-200083",
380 	},
381 	{ /* sentinel */ }
382 };
383 MODULE_DEVICE_TABLE(platform, hid_magn_3d_ids);
384 
385 static struct platform_driver hid_magn_3d_platform_driver = {
386 	.id_table = hid_magn_3d_ids,
387 	.driver = {
388 		.name	= KBUILD_MODNAME,
389 		.owner	= THIS_MODULE,
390 	},
391 	.probe		= hid_magn_3d_probe,
392 	.remove		= hid_magn_3d_remove,
393 };
394 module_platform_driver(hid_magn_3d_platform_driver);
395 
396 MODULE_DESCRIPTION("HID Sensor Magnetometer 3D");
397 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@intel.com>");
398 MODULE_LICENSE("GPL");
399