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/delay.h>
26 #include <linux/hid-sensor-hub.h>
27 #include <linux/iio/iio.h>
28 #include <linux/iio/sysfs.h>
29 #include <linux/iio/buffer.h>
30 #include <linux/iio/trigger_consumer.h>
31 #include <linux/iio/triggered_buffer.h>
32 #include "../common/hid-sensors/hid-sensor-trigger.h"
33 
34 enum {
35 	CHANNEL_SCAN_INDEX_INTENSITY = 0,
36 	CHANNEL_SCAN_INDEX_ILLUM = 1,
37 	CHANNEL_SCAN_INDEX_MAX
38 };
39 
40 struct als_state {
41 	struct hid_sensor_hub_callbacks callbacks;
42 	struct hid_sensor_common common_attributes;
43 	struct hid_sensor_hub_attribute_info als_illum;
44 	u32 illum[CHANNEL_SCAN_INDEX_MAX];
45 	int scale_pre_decml;
46 	int scale_post_decml;
47 	int scale_precision;
48 	int value_offset;
49 };
50 
51 /* Channel definitions */
52 static const struct iio_chan_spec als_channels[] = {
53 	{
54 		.type = IIO_INTENSITY,
55 		.modified = 1,
56 		.channel2 = IIO_MOD_LIGHT_BOTH,
57 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
58 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
59 		BIT(IIO_CHAN_INFO_SCALE) |
60 		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
61 		BIT(IIO_CHAN_INFO_HYSTERESIS),
62 		.scan_index = CHANNEL_SCAN_INDEX_INTENSITY,
63 	},
64 	{
65 		.type = IIO_LIGHT,
66 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
67 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
68 		BIT(IIO_CHAN_INFO_SCALE) |
69 		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
70 		BIT(IIO_CHAN_INFO_HYSTERESIS),
71 		.scan_index = CHANNEL_SCAN_INDEX_ILLUM,
72 	}
73 };
74 
75 /* Adjust channel real bits based on report descriptor */
76 static void als_adjust_channel_bit_mask(struct iio_chan_spec *channels,
77 					int channel, int size)
78 {
79 	channels[channel].scan_type.sign = 's';
80 	/* Real storage bits will change based on the report desc. */
81 	channels[channel].scan_type.realbits = size * 8;
82 	/* Maximum size of a sample to capture is u32 */
83 	channels[channel].scan_type.storagebits = sizeof(u32) * 8;
84 }
85 
86 /* Channel read_raw handler */
87 static int als_read_raw(struct iio_dev *indio_dev,
88 			      struct iio_chan_spec const *chan,
89 			      int *val, int *val2,
90 			      long mask)
91 {
92 	struct als_state *als_state = iio_priv(indio_dev);
93 	int report_id = -1;
94 	u32 address;
95 	int ret_type;
96 
97 	*val = 0;
98 	*val2 = 0;
99 	switch (mask) {
100 	case 0:
101 		switch (chan->scan_index) {
102 		case  CHANNEL_SCAN_INDEX_INTENSITY:
103 		case  CHANNEL_SCAN_INDEX_ILLUM:
104 			report_id = als_state->als_illum.report_id;
105 			address =
106 			HID_USAGE_SENSOR_LIGHT_ILLUM;
107 			break;
108 		default:
109 			report_id = -1;
110 			break;
111 		}
112 		if (report_id >= 0) {
113 			hid_sensor_power_state(&als_state->common_attributes,
114 						true);
115 			*val = sensor_hub_input_attr_get_raw_value(
116 					als_state->common_attributes.hsdev,
117 					HID_USAGE_SENSOR_ALS, address,
118 					report_id,
119 					SENSOR_HUB_SYNC);
120 			hid_sensor_power_state(&als_state->common_attributes,
121 						false);
122 		} else {
123 			*val = 0;
124 			return -EINVAL;
125 		}
126 		ret_type = IIO_VAL_INT;
127 		break;
128 	case IIO_CHAN_INFO_SCALE:
129 		*val = als_state->scale_pre_decml;
130 		*val2 = als_state->scale_post_decml;
131 		ret_type = als_state->scale_precision;
132 		break;
133 	case IIO_CHAN_INFO_OFFSET:
134 		*val = als_state->value_offset;
135 		ret_type = IIO_VAL_INT;
136 		break;
137 	case IIO_CHAN_INFO_SAMP_FREQ:
138 		ret_type = hid_sensor_read_samp_freq_value(
139 				&als_state->common_attributes, val, val2);
140 		break;
141 	case IIO_CHAN_INFO_HYSTERESIS:
142 		ret_type = hid_sensor_read_raw_hyst_value(
143 				&als_state->common_attributes, val, val2);
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 als_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 als_state *als_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 				&als_state->common_attributes, val, val2);
167 		break;
168 	case IIO_CHAN_INFO_HYSTERESIS:
169 		ret = hid_sensor_write_raw_hyst_value(
170 				&als_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 als_info = {
180 	.driver_module = THIS_MODULE,
181 	.read_raw = &als_read_raw,
182 	.write_raw = &als_write_raw,
183 };
184 
185 /* Function to push data to buffer */
186 static void hid_sensor_push_data(struct iio_dev *indio_dev, const void *data,
187 					int len)
188 {
189 	dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n");
190 	iio_push_to_buffers(indio_dev, data);
191 }
192 
193 /* Callback handler to send event after all samples are received and captured */
194 static int als_proc_event(struct hid_sensor_hub_device *hsdev,
195 				unsigned usage_id,
196 				void *priv)
197 {
198 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
199 	struct als_state *als_state = iio_priv(indio_dev);
200 
201 	dev_dbg(&indio_dev->dev, "als_proc_event\n");
202 	if (atomic_read(&als_state->common_attributes.data_ready))
203 		hid_sensor_push_data(indio_dev,
204 				&als_state->illum,
205 				sizeof(als_state->illum));
206 
207 	return 0;
208 }
209 
210 /* Capture samples in local storage */
211 static int als_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 als_state *als_state = iio_priv(indio_dev);
218 	int ret = -EINVAL;
219 	u32 sample_data = *(u32 *)raw_data;
220 
221 	switch (usage_id) {
222 	case HID_USAGE_SENSOR_LIGHT_ILLUM:
223 		als_state->illum[CHANNEL_SCAN_INDEX_INTENSITY] = sample_data;
224 		als_state->illum[CHANNEL_SCAN_INDEX_ILLUM] = sample_data;
225 		ret = 0;
226 		break;
227 	default:
228 		break;
229 	}
230 
231 	return ret;
232 }
233 
234 /* Parse report which is specific to an usage id*/
235 static int als_parse_report(struct platform_device *pdev,
236 				struct hid_sensor_hub_device *hsdev,
237 				struct iio_chan_spec *channels,
238 				unsigned usage_id,
239 				struct als_state *st)
240 {
241 	int ret;
242 
243 	ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
244 			usage_id,
245 			HID_USAGE_SENSOR_LIGHT_ILLUM,
246 			&st->als_illum);
247 	if (ret < 0)
248 		return ret;
249 	als_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_INTENSITY,
250 				    st->als_illum.size);
251 	als_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_ILLUM,
252 					st->als_illum.size);
253 
254 	dev_dbg(&pdev->dev, "als %x:%x\n", st->als_illum.index,
255 			st->als_illum.report_id);
256 
257 	st->scale_precision = hid_sensor_format_scale(
258 				HID_USAGE_SENSOR_ALS,
259 				&st->als_illum,
260 				&st->scale_pre_decml, &st->scale_post_decml);
261 
262 	/* Set Sensitivity field ids, when there is no individual modifier */
263 	if (st->common_attributes.sensitivity.index < 0) {
264 		sensor_hub_input_get_attribute_info(hsdev,
265 			HID_FEATURE_REPORT, usage_id,
266 			HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS |
267 			HID_USAGE_SENSOR_DATA_LIGHT,
268 			&st->common_attributes.sensitivity);
269 		dev_dbg(&pdev->dev, "Sensitivity index:report %d:%d\n",
270 			st->common_attributes.sensitivity.index,
271 			st->common_attributes.sensitivity.report_id);
272 	}
273 	return ret;
274 }
275 
276 /* Function to initialize the processing for usage id */
277 static int hid_als_probe(struct platform_device *pdev)
278 {
279 	int ret = 0;
280 	static const char *name = "als";
281 	struct iio_dev *indio_dev;
282 	struct als_state *als_state;
283 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
284 
285 	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(struct als_state));
286 	if (!indio_dev)
287 		return -ENOMEM;
288 	platform_set_drvdata(pdev, indio_dev);
289 
290 	als_state = iio_priv(indio_dev);
291 	als_state->common_attributes.hsdev = hsdev;
292 	als_state->common_attributes.pdev = pdev;
293 
294 	ret = hid_sensor_parse_common_attributes(hsdev, HID_USAGE_SENSOR_ALS,
295 					&als_state->common_attributes);
296 	if (ret) {
297 		dev_err(&pdev->dev, "failed to setup common attributes\n");
298 		return ret;
299 	}
300 
301 	indio_dev->channels = kmemdup(als_channels,
302 				      sizeof(als_channels), GFP_KERNEL);
303 	if (!indio_dev->channels) {
304 		dev_err(&pdev->dev, "failed to duplicate channels\n");
305 		return -ENOMEM;
306 	}
307 
308 	ret = als_parse_report(pdev, hsdev,
309 			       (struct iio_chan_spec *)indio_dev->channels,
310 			       HID_USAGE_SENSOR_ALS, als_state);
311 	if (ret) {
312 		dev_err(&pdev->dev, "failed to setup attributes\n");
313 		goto error_free_dev_mem;
314 	}
315 
316 	indio_dev->num_channels =
317 				ARRAY_SIZE(als_channels);
318 	indio_dev->dev.parent = &pdev->dev;
319 	indio_dev->info = &als_info;
320 	indio_dev->name = name;
321 	indio_dev->modes = INDIO_DIRECT_MODE;
322 
323 	ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
324 		NULL, NULL);
325 	if (ret) {
326 		dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
327 		goto error_free_dev_mem;
328 	}
329 	atomic_set(&als_state->common_attributes.data_ready, 0);
330 	ret = hid_sensor_setup_trigger(indio_dev, name,
331 				&als_state->common_attributes);
332 	if (ret < 0) {
333 		dev_err(&pdev->dev, "trigger setup failed\n");
334 		goto error_unreg_buffer_funcs;
335 	}
336 
337 	ret = iio_device_register(indio_dev);
338 	if (ret) {
339 		dev_err(&pdev->dev, "device register failed\n");
340 		goto error_remove_trigger;
341 	}
342 
343 	als_state->callbacks.send_event = als_proc_event;
344 	als_state->callbacks.capture_sample = als_capture_sample;
345 	als_state->callbacks.pdev = pdev;
346 	ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_ALS,
347 					&als_state->callbacks);
348 	if (ret < 0) {
349 		dev_err(&pdev->dev, "callback reg failed\n");
350 		goto error_iio_unreg;
351 	}
352 
353 	return ret;
354 
355 error_iio_unreg:
356 	iio_device_unregister(indio_dev);
357 error_remove_trigger:
358 	hid_sensor_remove_trigger(&als_state->common_attributes);
359 error_unreg_buffer_funcs:
360 	iio_triggered_buffer_cleanup(indio_dev);
361 error_free_dev_mem:
362 	kfree(indio_dev->channels);
363 	return ret;
364 }
365 
366 /* Function to deinitialize the processing for usage id */
367 static int hid_als_remove(struct platform_device *pdev)
368 {
369 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
370 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
371 	struct als_state *als_state = iio_priv(indio_dev);
372 
373 	sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_ALS);
374 	iio_device_unregister(indio_dev);
375 	hid_sensor_remove_trigger(&als_state->common_attributes);
376 	iio_triggered_buffer_cleanup(indio_dev);
377 	kfree(indio_dev->channels);
378 
379 	return 0;
380 }
381 
382 static const struct platform_device_id hid_als_ids[] = {
383 	{
384 		/* Format: HID-SENSOR-usage_id_in_hex_lowercase */
385 		.name = "HID-SENSOR-200041",
386 	},
387 	{ /* sentinel */ }
388 };
389 MODULE_DEVICE_TABLE(platform, hid_als_ids);
390 
391 static struct platform_driver hid_als_platform_driver = {
392 	.id_table = hid_als_ids,
393 	.driver = {
394 		.name	= KBUILD_MODNAME,
395 		.pm	= &hid_sensor_pm_ops,
396 	},
397 	.probe		= hid_als_probe,
398 	.remove		= hid_als_remove,
399 };
400 module_platform_driver(hid_als_platform_driver);
401 
402 MODULE_DESCRIPTION("HID Sensor ALS");
403 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@intel.com>");
404 MODULE_LICENSE("GPL");
405