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-attributes.h"
32 #include "../common/hid-sensors/hid-sensor-trigger.h"
33 
34 /*Format: HID-SENSOR-usage_id_in_hex*/
35 /*Usage ID from spec for Magnetometer-3D: 0x200083*/
36 #define DRIVER_NAME "HID-SENSOR-200083"
37 
38 enum magn_3d_channel {
39 	CHANNEL_SCAN_INDEX_X,
40 	CHANNEL_SCAN_INDEX_Y,
41 	CHANNEL_SCAN_INDEX_Z,
42 	MAGN_3D_CHANNEL_MAX,
43 };
44 
45 struct magn_3d_state {
46 	struct hid_sensor_hub_callbacks callbacks;
47 	struct hid_sensor_iio_common common_attributes;
48 	struct hid_sensor_hub_attribute_info magn[MAGN_3D_CHANNEL_MAX];
49 	u32 magn_val[MAGN_3D_CHANNEL_MAX];
50 };
51 
52 static const u32 magn_3d_addresses[MAGN_3D_CHANNEL_MAX] = {
53 	HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_X_AXIS,
54 	HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_Y_AXIS,
55 	HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_Z_AXIS
56 };
57 
58 /* Channel definitions */
59 static const struct iio_chan_spec magn_3d_channels[] = {
60 	{
61 		.type = IIO_MAGN,
62 		.modified = 1,
63 		.channel2 = IIO_MOD_X,
64 		.info_mask = IIO_CHAN_INFO_OFFSET_SHARED_BIT |
65 		IIO_CHAN_INFO_SCALE_SHARED_BIT |
66 		IIO_CHAN_INFO_SAMP_FREQ_SHARED_BIT |
67 		IIO_CHAN_INFO_HYSTERESIS_SHARED_BIT,
68 		.scan_index = CHANNEL_SCAN_INDEX_X,
69 	}, {
70 		.type = IIO_MAGN,
71 		.modified = 1,
72 		.channel2 = IIO_MOD_Y,
73 		.info_mask = IIO_CHAN_INFO_OFFSET_SHARED_BIT |
74 		IIO_CHAN_INFO_SCALE_SHARED_BIT |
75 		IIO_CHAN_INFO_SAMP_FREQ_SHARED_BIT |
76 		IIO_CHAN_INFO_HYSTERESIS_SHARED_BIT,
77 		.scan_index = CHANNEL_SCAN_INDEX_Y,
78 	}, {
79 		.type = IIO_MAGN,
80 		.modified = 1,
81 		.channel2 = IIO_MOD_Z,
82 		.info_mask = IIO_CHAN_INFO_OFFSET_SHARED_BIT |
83 		IIO_CHAN_INFO_SCALE_SHARED_BIT |
84 		IIO_CHAN_INFO_SAMP_FREQ_SHARED_BIT |
85 		IIO_CHAN_INFO_HYSTERESIS_SHARED_BIT,
86 		.scan_index = CHANNEL_SCAN_INDEX_Z,
87 	}
88 };
89 
90 /* Adjust channel real bits based on report descriptor */
91 static void magn_3d_adjust_channel_bit_mask(struct iio_chan_spec *channels,
92 						int channel, int size)
93 {
94 	channels[channel].scan_type.sign = 's';
95 	/* Real storage bits will change based on the report desc. */
96 	channels[channel].scan_type.realbits = size * 8;
97 	/* Maximum size of a sample to capture is u32 */
98 	channels[channel].scan_type.storagebits = sizeof(u32) * 8;
99 }
100 
101 /* Channel read_raw handler */
102 static int magn_3d_read_raw(struct iio_dev *indio_dev,
103 			      struct iio_chan_spec const *chan,
104 			      int *val, int *val2,
105 			      long mask)
106 {
107 	struct magn_3d_state *magn_state = iio_priv(indio_dev);
108 	int report_id = -1;
109 	u32 address;
110 	int ret;
111 	int ret_type;
112 
113 	*val = 0;
114 	*val2 = 0;
115 	switch (mask) {
116 	case 0:
117 		report_id =
118 			magn_state->magn[chan->scan_index].report_id;
119 		address = magn_3d_addresses[chan->scan_index];
120 		if (report_id >= 0)
121 			*val = sensor_hub_input_attr_get_raw_value(
122 				magn_state->common_attributes.hsdev,
123 				HID_USAGE_SENSOR_COMPASS_3D, address,
124 				report_id);
125 		else {
126 			*val = 0;
127 			return -EINVAL;
128 		}
129 		ret_type = IIO_VAL_INT;
130 		break;
131 	case IIO_CHAN_INFO_SCALE:
132 		*val = magn_state->magn[CHANNEL_SCAN_INDEX_X].units;
133 		ret_type = IIO_VAL_INT;
134 		break;
135 	case IIO_CHAN_INFO_OFFSET:
136 		*val = hid_sensor_convert_exponent(
137 			magn_state->magn[CHANNEL_SCAN_INDEX_X].unit_expo);
138 		ret_type = IIO_VAL_INT;
139 		break;
140 	case IIO_CHAN_INFO_SAMP_FREQ:
141 		ret = hid_sensor_read_samp_freq_value(
142 			&magn_state->common_attributes, val, val2);
143 		ret_type = IIO_VAL_INT_PLUS_MICRO;
144 		break;
145 	case IIO_CHAN_INFO_HYSTERESIS:
146 		ret = hid_sensor_read_raw_hyst_value(
147 			&magn_state->common_attributes, val, val2);
148 		ret_type = IIO_VAL_INT_PLUS_MICRO;
149 		break;
150 	default:
151 		ret_type = -EINVAL;
152 		break;
153 	}
154 
155 	return ret_type;
156 }
157 
158 /* Channel write_raw handler */
159 static int magn_3d_write_raw(struct iio_dev *indio_dev,
160 			       struct iio_chan_spec const *chan,
161 			       int val,
162 			       int val2,
163 			       long mask)
164 {
165 	struct magn_3d_state *magn_state = iio_priv(indio_dev);
166 	int ret = 0;
167 
168 	switch (mask) {
169 	case IIO_CHAN_INFO_SAMP_FREQ:
170 		ret = hid_sensor_write_samp_freq_value(
171 				&magn_state->common_attributes, val, val2);
172 		break;
173 	case IIO_CHAN_INFO_HYSTERESIS:
174 		ret = hid_sensor_write_raw_hyst_value(
175 				&magn_state->common_attributes, val, val2);
176 		break;
177 	default:
178 		ret = -EINVAL;
179 	}
180 
181 	return ret;
182 }
183 
184 static int magn_3d_write_raw_get_fmt(struct iio_dev *indio_dev,
185 			       struct iio_chan_spec const *chan,
186 			       long mask)
187 {
188 	return IIO_VAL_INT_PLUS_MICRO;
189 }
190 
191 static const struct iio_info magn_3d_info = {
192 	.driver_module = THIS_MODULE,
193 	.read_raw = &magn_3d_read_raw,
194 	.write_raw = &magn_3d_write_raw,
195 	.write_raw_get_fmt = &magn_3d_write_raw_get_fmt,
196 };
197 
198 /* Function to push data to buffer */
199 static void hid_sensor_push_data(struct iio_dev *indio_dev, u8 *data, int len)
200 {
201 	struct iio_buffer *buffer = indio_dev->buffer;
202 	int datum_sz;
203 
204 	dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n");
205 	if (!buffer) {
206 		dev_err(&indio_dev->dev, "Buffer == NULL\n");
207 		return;
208 	}
209 	datum_sz = buffer->access->get_bytes_per_datum(buffer);
210 	if (len > datum_sz) {
211 		dev_err(&indio_dev->dev, "Datum size mismatch %d:%d\n", len,
212 				datum_sz);
213 		return;
214 	}
215 	iio_push_to_buffer(buffer, (u8 *)data);
216 }
217 
218 /* Callback handler to send event after all samples are received and captured */
219 static int magn_3d_proc_event(struct hid_sensor_hub_device *hsdev,
220 				unsigned usage_id,
221 				void *priv)
222 {
223 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
224 	struct magn_3d_state *magn_state = iio_priv(indio_dev);
225 
226 	dev_dbg(&indio_dev->dev, "magn_3d_proc_event [%d]\n",
227 				magn_state->common_attributes.data_ready);
228 	if (magn_state->common_attributes.data_ready)
229 		hid_sensor_push_data(indio_dev,
230 				(u8 *)magn_state->magn_val,
231 				sizeof(magn_state->magn_val));
232 
233 	return 0;
234 }
235 
236 /* Capture samples in local storage */
237 static int magn_3d_capture_sample(struct hid_sensor_hub_device *hsdev,
238 				unsigned usage_id,
239 				size_t raw_len, char *raw_data,
240 				void *priv)
241 {
242 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
243 	struct magn_3d_state *magn_state = iio_priv(indio_dev);
244 	int offset;
245 	int ret = -EINVAL;
246 
247 	switch (usage_id) {
248 	case HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_X_AXIS:
249 	case HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_Y_AXIS:
250 	case HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_Z_AXIS:
251 		offset = usage_id - HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_X_AXIS;
252 		magn_state->magn_val[CHANNEL_SCAN_INDEX_X + offset] =
253 						*(u32 *)raw_data;
254 		ret = 0;
255 	break;
256 	default:
257 		break;
258 	}
259 
260 	return ret;
261 }
262 
263 /* Parse report which is specific to an usage id*/
264 static int magn_3d_parse_report(struct platform_device *pdev,
265 				struct hid_sensor_hub_device *hsdev,
266 				struct iio_chan_spec *channels,
267 				unsigned usage_id,
268 				struct magn_3d_state *st)
269 {
270 	int ret;
271 	int i;
272 
273 	for (i = 0; i <= CHANNEL_SCAN_INDEX_Z; ++i) {
274 		ret = sensor_hub_input_get_attribute_info(hsdev,
275 				HID_INPUT_REPORT,
276 				usage_id,
277 				HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_X_AXIS + i,
278 				&st->magn[CHANNEL_SCAN_INDEX_X + i]);
279 		if (ret < 0)
280 			break;
281 		magn_3d_adjust_channel_bit_mask(channels,
282 				CHANNEL_SCAN_INDEX_X + i,
283 				st->magn[CHANNEL_SCAN_INDEX_X + i].size);
284 	}
285 	dev_dbg(&pdev->dev, "magn_3d %x:%x, %x:%x, %x:%x\n",
286 			st->magn[0].index,
287 			st->magn[0].report_id,
288 			st->magn[1].index, st->magn[1].report_id,
289 			st->magn[2].index, st->magn[2].report_id);
290 
291 	return ret;
292 }
293 
294 /* Function to initialize the processing for usage id */
295 static int __devinit hid_magn_3d_probe(struct platform_device *pdev)
296 {
297 	int ret = 0;
298 	static char *name = "magn_3d";
299 	struct iio_dev *indio_dev;
300 	struct magn_3d_state *magn_state;
301 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
302 	struct iio_chan_spec *channels;
303 
304 	indio_dev = iio_device_alloc(sizeof(struct magn_3d_state));
305 	if (indio_dev == NULL) {
306 		ret = -ENOMEM;
307 		goto error_ret;
308 	}
309 	platform_set_drvdata(pdev, indio_dev);
310 
311 	magn_state = iio_priv(indio_dev);
312 	magn_state->common_attributes.hsdev = hsdev;
313 	magn_state->common_attributes.pdev = pdev;
314 
315 	ret = hid_sensor_parse_common_attributes(hsdev,
316 				HID_USAGE_SENSOR_COMPASS_3D,
317 				&magn_state->common_attributes);
318 	if (ret) {
319 		dev_err(&pdev->dev, "failed to setup common attributes\n");
320 		goto error_free_dev;
321 	}
322 
323 	channels = kmemdup(magn_3d_channels,
324 					sizeof(magn_3d_channels),
325 					GFP_KERNEL);
326 	if (!channels) {
327 		dev_err(&pdev->dev, "failed to duplicate channels\n");
328 		goto error_free_dev;
329 	}
330 
331 	ret = magn_3d_parse_report(pdev, hsdev, channels,
332 				HID_USAGE_SENSOR_COMPASS_3D, magn_state);
333 	if (ret) {
334 		dev_err(&pdev->dev, "failed to setup attributes\n");
335 		goto error_free_dev_mem;
336 	}
337 
338 	indio_dev->channels = channels;
339 	indio_dev->num_channels = ARRAY_SIZE(magn_3d_channels);
340 	indio_dev->dev.parent = &pdev->dev;
341 	indio_dev->info = &magn_3d_info;
342 	indio_dev->name = name;
343 	indio_dev->modes = INDIO_DIRECT_MODE;
344 
345 	ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
346 		NULL, NULL);
347 	if (ret) {
348 		dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
349 		goto error_free_dev_mem;
350 	}
351 	magn_state->common_attributes.data_ready = false;
352 	ret = hid_sensor_setup_trigger(indio_dev, name,
353 					&magn_state->common_attributes);
354 	if (ret < 0) {
355 		dev_err(&pdev->dev, "trigger setup failed\n");
356 		goto error_unreg_buffer_funcs;
357 	}
358 
359 	ret = iio_device_register(indio_dev);
360 	if (ret) {
361 		dev_err(&pdev->dev, "device register failed\n");
362 		goto error_remove_trigger;
363 	}
364 
365 	magn_state->callbacks.send_event = magn_3d_proc_event;
366 	magn_state->callbacks.capture_sample = magn_3d_capture_sample;
367 	magn_state->callbacks.pdev = pdev;
368 	ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_COMPASS_3D,
369 					&magn_state->callbacks);
370 	if (ret < 0) {
371 		dev_err(&pdev->dev, "callback reg failed\n");
372 		goto error_iio_unreg;
373 	}
374 
375 	return ret;
376 
377 error_iio_unreg:
378 	iio_device_unregister(indio_dev);
379 error_remove_trigger:
380 	hid_sensor_remove_trigger(indio_dev);
381 error_unreg_buffer_funcs:
382 	iio_triggered_buffer_cleanup(indio_dev);
383 error_free_dev_mem:
384 	kfree(indio_dev->channels);
385 error_free_dev:
386 	iio_device_free(indio_dev);
387 error_ret:
388 	return ret;
389 }
390 
391 /* Function to deinitialize the processing for usage id */
392 static int __devinit hid_magn_3d_remove(struct platform_device *pdev)
393 {
394 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
395 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
396 
397 	sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_COMPASS_3D);
398 	iio_device_unregister(indio_dev);
399 	hid_sensor_remove_trigger(indio_dev);
400 	iio_triggered_buffer_cleanup(indio_dev);
401 	kfree(indio_dev->channels);
402 	iio_device_free(indio_dev);
403 
404 	return 0;
405 }
406 
407 static struct platform_driver hid_magn_3d_platform_driver = {
408 	.driver = {
409 		.name	= DRIVER_NAME,
410 		.owner	= THIS_MODULE,
411 	},
412 	.probe		= hid_magn_3d_probe,
413 	.remove		= hid_magn_3d_remove,
414 };
415 module_platform_driver(hid_magn_3d_platform_driver);
416 
417 MODULE_DESCRIPTION("HID Sensor Magnetometer 3D");
418 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@intel.com>");
419 MODULE_LICENSE("GPL");
420