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 #define CHANNEL_SCAN_INDEX_ILLUM 0
35 
36 struct als_state {
37 	struct hid_sensor_hub_callbacks callbacks;
38 	struct hid_sensor_common common_attributes;
39 	struct hid_sensor_hub_attribute_info als_illum;
40 	u32 illum;
41 	int scale_pre_decml;
42 	int scale_post_decml;
43 	int scale_precision;
44 	int value_offset;
45 };
46 
47 /* Channel definitions */
48 static const struct iio_chan_spec als_channels[] = {
49 	{
50 		.type = IIO_INTENSITY,
51 		.modified = 1,
52 		.channel2 = IIO_MOD_LIGHT_BOTH,
53 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
54 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
55 		BIT(IIO_CHAN_INFO_SCALE) |
56 		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
57 		BIT(IIO_CHAN_INFO_HYSTERESIS),
58 		.scan_index = CHANNEL_SCAN_INDEX_ILLUM,
59 	}
60 };
61 
62 /* Adjust channel real bits based on report descriptor */
63 static void als_adjust_channel_bit_mask(struct iio_chan_spec *channels,
64 					int channel, int size)
65 {
66 	channels[channel].scan_type.sign = 's';
67 	/* Real storage bits will change based on the report desc. */
68 	channels[channel].scan_type.realbits = size * 8;
69 	/* Maximum size of a sample to capture is u32 */
70 	channels[channel].scan_type.storagebits = sizeof(u32) * 8;
71 }
72 
73 /* Channel read_raw handler */
74 static int als_read_raw(struct iio_dev *indio_dev,
75 			      struct iio_chan_spec const *chan,
76 			      int *val, int *val2,
77 			      long mask)
78 {
79 	struct als_state *als_state = iio_priv(indio_dev);
80 	int report_id = -1;
81 	u32 address;
82 	int ret_type;
83 	s32 poll_value;
84 
85 	*val = 0;
86 	*val2 = 0;
87 	switch (mask) {
88 	case 0:
89 		switch (chan->scan_index) {
90 		case  CHANNEL_SCAN_INDEX_ILLUM:
91 			report_id = als_state->als_illum.report_id;
92 			address =
93 			HID_USAGE_SENSOR_LIGHT_ILLUM;
94 			break;
95 		default:
96 			report_id = -1;
97 			break;
98 		}
99 		if (report_id >= 0) {
100 			poll_value = hid_sensor_read_poll_value(
101 						&als_state->common_attributes);
102 			if (poll_value < 0)
103 				return -EINVAL;
104 
105 			hid_sensor_power_state(&als_state->common_attributes,
106 						true);
107 			msleep_interruptible(poll_value * 2);
108 
109 			*val = sensor_hub_input_attr_get_raw_value(
110 					als_state->common_attributes.hsdev,
111 					HID_USAGE_SENSOR_ALS, address,
112 					report_id);
113 			hid_sensor_power_state(&als_state->common_attributes,
114 						false);
115 		} else {
116 			*val = 0;
117 			return -EINVAL;
118 		}
119 		ret_type = IIO_VAL_INT;
120 		break;
121 	case IIO_CHAN_INFO_SCALE:
122 		*val = als_state->scale_pre_decml;
123 		*val2 = als_state->scale_post_decml;
124 		ret_type = als_state->scale_precision;
125 		break;
126 	case IIO_CHAN_INFO_OFFSET:
127 		*val = als_state->value_offset;
128 		ret_type = IIO_VAL_INT;
129 		break;
130 	case IIO_CHAN_INFO_SAMP_FREQ:
131 		ret_type = hid_sensor_read_samp_freq_value(
132 				&als_state->common_attributes, val, val2);
133 		break;
134 	case IIO_CHAN_INFO_HYSTERESIS:
135 		ret_type = hid_sensor_read_raw_hyst_value(
136 				&als_state->common_attributes, val, val2);
137 		break;
138 	default:
139 		ret_type = -EINVAL;
140 		break;
141 	}
142 
143 	return ret_type;
144 }
145 
146 /* Channel write_raw handler */
147 static int als_write_raw(struct iio_dev *indio_dev,
148 			       struct iio_chan_spec const *chan,
149 			       int val,
150 			       int val2,
151 			       long mask)
152 {
153 	struct als_state *als_state = iio_priv(indio_dev);
154 	int ret = 0;
155 
156 	switch (mask) {
157 	case IIO_CHAN_INFO_SAMP_FREQ:
158 		ret = hid_sensor_write_samp_freq_value(
159 				&als_state->common_attributes, val, val2);
160 		break;
161 	case IIO_CHAN_INFO_HYSTERESIS:
162 		ret = hid_sensor_write_raw_hyst_value(
163 				&als_state->common_attributes, val, val2);
164 		break;
165 	default:
166 		ret = -EINVAL;
167 	}
168 
169 	return ret;
170 }
171 
172 static const struct iio_info als_info = {
173 	.driver_module = THIS_MODULE,
174 	.read_raw = &als_read_raw,
175 	.write_raw = &als_write_raw,
176 };
177 
178 /* Function to push data to buffer */
179 static void hid_sensor_push_data(struct iio_dev *indio_dev, const void *data,
180 					int len)
181 {
182 	dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n");
183 	iio_push_to_buffers(indio_dev, data);
184 }
185 
186 /* Callback handler to send event after all samples are received and captured */
187 static int als_proc_event(struct hid_sensor_hub_device *hsdev,
188 				unsigned usage_id,
189 				void *priv)
190 {
191 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
192 	struct als_state *als_state = iio_priv(indio_dev);
193 
194 	dev_dbg(&indio_dev->dev, "als_proc_event\n");
195 	if (atomic_read(&als_state->common_attributes.data_ready))
196 		hid_sensor_push_data(indio_dev,
197 				&als_state->illum,
198 				sizeof(als_state->illum));
199 
200 	return 0;
201 }
202 
203 /* Capture samples in local storage */
204 static int als_capture_sample(struct hid_sensor_hub_device *hsdev,
205 				unsigned usage_id,
206 				size_t raw_len, char *raw_data,
207 				void *priv)
208 {
209 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
210 	struct als_state *als_state = iio_priv(indio_dev);
211 	int ret = -EINVAL;
212 
213 	switch (usage_id) {
214 	case HID_USAGE_SENSOR_LIGHT_ILLUM:
215 		als_state->illum = *(u32 *)raw_data;
216 		ret = 0;
217 		break;
218 	default:
219 		break;
220 	}
221 
222 	return ret;
223 }
224 
225 /* Parse report which is specific to an usage id*/
226 static int als_parse_report(struct platform_device *pdev,
227 				struct hid_sensor_hub_device *hsdev,
228 				struct iio_chan_spec *channels,
229 				unsigned usage_id,
230 				struct als_state *st)
231 {
232 	int ret;
233 
234 	ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
235 			usage_id,
236 			HID_USAGE_SENSOR_LIGHT_ILLUM,
237 			&st->als_illum);
238 	if (ret < 0)
239 		return ret;
240 	als_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_ILLUM,
241 					st->als_illum.size);
242 
243 	dev_dbg(&pdev->dev, "als %x:%x\n", st->als_illum.index,
244 			st->als_illum.report_id);
245 
246 	st->scale_precision = hid_sensor_format_scale(
247 				HID_USAGE_SENSOR_ALS,
248 				&st->als_illum,
249 				&st->scale_pre_decml, &st->scale_post_decml);
250 
251 	/* Set Sensitivity field ids, when there is no individual modifier */
252 	if (st->common_attributes.sensitivity.index < 0) {
253 		sensor_hub_input_get_attribute_info(hsdev,
254 			HID_FEATURE_REPORT, usage_id,
255 			HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS |
256 			HID_USAGE_SENSOR_DATA_LIGHT,
257 			&st->common_attributes.sensitivity);
258 		dev_dbg(&pdev->dev, "Sensitivity index:report %d:%d\n",
259 			st->common_attributes.sensitivity.index,
260 			st->common_attributes.sensitivity.report_id);
261 	}
262 	return ret;
263 }
264 
265 /* Function to initialize the processing for usage id */
266 static int hid_als_probe(struct platform_device *pdev)
267 {
268 	int ret = 0;
269 	static const char *name = "als";
270 	struct iio_dev *indio_dev;
271 	struct als_state *als_state;
272 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
273 	struct iio_chan_spec *channels;
274 
275 	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(struct als_state));
276 	if (!indio_dev)
277 		return -ENOMEM;
278 	platform_set_drvdata(pdev, indio_dev);
279 
280 	als_state = iio_priv(indio_dev);
281 	als_state->common_attributes.hsdev = hsdev;
282 	als_state->common_attributes.pdev = pdev;
283 
284 	ret = hid_sensor_parse_common_attributes(hsdev, HID_USAGE_SENSOR_ALS,
285 					&als_state->common_attributes);
286 	if (ret) {
287 		dev_err(&pdev->dev, "failed to setup common attributes\n");
288 		return ret;
289 	}
290 
291 	channels = kmemdup(als_channels, sizeof(als_channels), GFP_KERNEL);
292 	if (!channels) {
293 		dev_err(&pdev->dev, "failed to duplicate channels\n");
294 		return -ENOMEM;
295 	}
296 
297 	ret = als_parse_report(pdev, hsdev, channels,
298 				HID_USAGE_SENSOR_ALS, als_state);
299 	if (ret) {
300 		dev_err(&pdev->dev, "failed to setup attributes\n");
301 		goto error_free_dev_mem;
302 	}
303 
304 	indio_dev->channels = channels;
305 	indio_dev->num_channels =
306 				ARRAY_SIZE(als_channels);
307 	indio_dev->dev.parent = &pdev->dev;
308 	indio_dev->info = &als_info;
309 	indio_dev->name = name;
310 	indio_dev->modes = INDIO_DIRECT_MODE;
311 
312 	ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
313 		NULL, NULL);
314 	if (ret) {
315 		dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
316 		goto error_free_dev_mem;
317 	}
318 	atomic_set(&als_state->common_attributes.data_ready, 0);
319 	ret = hid_sensor_setup_trigger(indio_dev, name,
320 				&als_state->common_attributes);
321 	if (ret < 0) {
322 		dev_err(&pdev->dev, "trigger setup failed\n");
323 		goto error_unreg_buffer_funcs;
324 	}
325 
326 	ret = iio_device_register(indio_dev);
327 	if (ret) {
328 		dev_err(&pdev->dev, "device register failed\n");
329 		goto error_remove_trigger;
330 	}
331 
332 	als_state->callbacks.send_event = als_proc_event;
333 	als_state->callbacks.capture_sample = als_capture_sample;
334 	als_state->callbacks.pdev = pdev;
335 	ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_ALS,
336 					&als_state->callbacks);
337 	if (ret < 0) {
338 		dev_err(&pdev->dev, "callback reg failed\n");
339 		goto error_iio_unreg;
340 	}
341 
342 	return ret;
343 
344 error_iio_unreg:
345 	iio_device_unregister(indio_dev);
346 error_remove_trigger:
347 	hid_sensor_remove_trigger(&als_state->common_attributes);
348 error_unreg_buffer_funcs:
349 	iio_triggered_buffer_cleanup(indio_dev);
350 error_free_dev_mem:
351 	kfree(indio_dev->channels);
352 	return ret;
353 }
354 
355 /* Function to deinitialize the processing for usage id */
356 static int hid_als_remove(struct platform_device *pdev)
357 {
358 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
359 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
360 	struct als_state *als_state = iio_priv(indio_dev);
361 
362 	sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_ALS);
363 	iio_device_unregister(indio_dev);
364 	hid_sensor_remove_trigger(&als_state->common_attributes);
365 	iio_triggered_buffer_cleanup(indio_dev);
366 	kfree(indio_dev->channels);
367 
368 	return 0;
369 }
370 
371 static struct platform_device_id hid_als_ids[] = {
372 	{
373 		/* Format: HID-SENSOR-usage_id_in_hex_lowercase */
374 		.name = "HID-SENSOR-200041",
375 	},
376 	{ /* sentinel */ }
377 };
378 MODULE_DEVICE_TABLE(platform, hid_als_ids);
379 
380 static struct platform_driver hid_als_platform_driver = {
381 	.id_table = hid_als_ids,
382 	.driver = {
383 		.name	= KBUILD_MODNAME,
384 	},
385 	.probe		= hid_als_probe,
386 	.remove		= hid_als_remove,
387 };
388 module_platform_driver(hid_als_platform_driver);
389 
390 MODULE_DESCRIPTION("HID Sensor ALS");
391 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@intel.com>");
392 MODULE_LICENSE("GPL");
393