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 #define CHANNEL_SCAN_INDEX_ILLUM 0
34 
35 struct als_state {
36 	struct hid_sensor_hub_callbacks callbacks;
37 	struct hid_sensor_common common_attributes;
38 	struct hid_sensor_hub_attribute_info als_illum;
39 	u32 illum;
40 };
41 
42 /* Channel definitions */
43 static const struct iio_chan_spec als_channels[] = {
44 	{
45 		.type = IIO_INTENSITY,
46 		.modified = 1,
47 		.channel2 = IIO_MOD_LIGHT_BOTH,
48 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
49 		BIT(IIO_CHAN_INFO_SCALE) |
50 		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
51 		BIT(IIO_CHAN_INFO_HYSTERESIS),
52 		.scan_index = CHANNEL_SCAN_INDEX_ILLUM,
53 	}
54 };
55 
56 /* Adjust channel real bits based on report descriptor */
57 static void als_adjust_channel_bit_mask(struct iio_chan_spec *channels,
58 					int channel, int size)
59 {
60 	channels[channel].scan_type.sign = 's';
61 	/* Real storage bits will change based on the report desc. */
62 	channels[channel].scan_type.realbits = size * 8;
63 	/* Maximum size of a sample to capture is u32 */
64 	channels[channel].scan_type.storagebits = sizeof(u32) * 8;
65 }
66 
67 /* Channel read_raw handler */
68 static int als_read_raw(struct iio_dev *indio_dev,
69 			      struct iio_chan_spec const *chan,
70 			      int *val, int *val2,
71 			      long mask)
72 {
73 	struct als_state *als_state = iio_priv(indio_dev);
74 	int report_id = -1;
75 	u32 address;
76 	int ret;
77 	int ret_type;
78 
79 	*val = 0;
80 	*val2 = 0;
81 	switch (mask) {
82 	case 0:
83 		switch (chan->scan_index) {
84 		case  CHANNEL_SCAN_INDEX_ILLUM:
85 			report_id = als_state->als_illum.report_id;
86 			address =
87 			HID_USAGE_SENSOR_LIGHT_ILLUM;
88 			break;
89 		default:
90 			report_id = -1;
91 			break;
92 		}
93 		if (report_id >= 0)
94 			*val = sensor_hub_input_attr_get_raw_value(
95 				als_state->common_attributes.hsdev,
96 				HID_USAGE_SENSOR_ALS, address,
97 				report_id);
98 		else {
99 			*val = 0;
100 			return -EINVAL;
101 		}
102 		ret_type = IIO_VAL_INT;
103 		break;
104 	case IIO_CHAN_INFO_SCALE:
105 		*val = als_state->als_illum.units;
106 		ret_type = IIO_VAL_INT;
107 		break;
108 	case IIO_CHAN_INFO_OFFSET:
109 		*val = hid_sensor_convert_exponent(
110 				als_state->als_illum.unit_expo);
111 		ret_type = IIO_VAL_INT;
112 		break;
113 	case IIO_CHAN_INFO_SAMP_FREQ:
114 		ret = hid_sensor_read_samp_freq_value(
115 				&als_state->common_attributes, val, val2);
116 		ret_type = IIO_VAL_INT_PLUS_MICRO;
117 		break;
118 	case IIO_CHAN_INFO_HYSTERESIS:
119 		ret = hid_sensor_read_raw_hyst_value(
120 				&als_state->common_attributes, val, val2);
121 		ret_type = IIO_VAL_INT_PLUS_MICRO;
122 		break;
123 	default:
124 		ret_type = -EINVAL;
125 		break;
126 	}
127 
128 	return ret_type;
129 }
130 
131 /* Channel write_raw handler */
132 static int als_write_raw(struct iio_dev *indio_dev,
133 			       struct iio_chan_spec const *chan,
134 			       int val,
135 			       int val2,
136 			       long mask)
137 {
138 	struct als_state *als_state = iio_priv(indio_dev);
139 	int ret = 0;
140 
141 	switch (mask) {
142 	case IIO_CHAN_INFO_SAMP_FREQ:
143 		ret = hid_sensor_write_samp_freq_value(
144 				&als_state->common_attributes, val, val2);
145 		break;
146 	case IIO_CHAN_INFO_HYSTERESIS:
147 		ret = hid_sensor_write_raw_hyst_value(
148 				&als_state->common_attributes, val, val2);
149 		break;
150 	default:
151 		ret = -EINVAL;
152 	}
153 
154 	return ret;
155 }
156 
157 static const struct iio_info als_info = {
158 	.driver_module = THIS_MODULE,
159 	.read_raw = &als_read_raw,
160 	.write_raw = &als_write_raw,
161 };
162 
163 /* Function to push data to buffer */
164 static void hid_sensor_push_data(struct iio_dev *indio_dev, const void *data,
165 					int len)
166 {
167 	dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n");
168 	iio_push_to_buffers(indio_dev, data);
169 }
170 
171 /* Callback handler to send event after all samples are received and captured */
172 static int als_proc_event(struct hid_sensor_hub_device *hsdev,
173 				unsigned usage_id,
174 				void *priv)
175 {
176 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
177 	struct als_state *als_state = iio_priv(indio_dev);
178 
179 	dev_dbg(&indio_dev->dev, "als_proc_event [%d]\n",
180 				als_state->common_attributes.data_ready);
181 	if (als_state->common_attributes.data_ready)
182 		hid_sensor_push_data(indio_dev,
183 				&als_state->illum,
184 				sizeof(als_state->illum));
185 
186 	return 0;
187 }
188 
189 /* Capture samples in local storage */
190 static int als_capture_sample(struct hid_sensor_hub_device *hsdev,
191 				unsigned usage_id,
192 				size_t raw_len, char *raw_data,
193 				void *priv)
194 {
195 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
196 	struct als_state *als_state = iio_priv(indio_dev);
197 	int ret = -EINVAL;
198 
199 	switch (usage_id) {
200 	case HID_USAGE_SENSOR_LIGHT_ILLUM:
201 		als_state->illum = *(u32 *)raw_data;
202 		ret = 0;
203 		break;
204 	default:
205 		break;
206 	}
207 
208 	return ret;
209 }
210 
211 /* Parse report which is specific to an usage id*/
212 static int als_parse_report(struct platform_device *pdev,
213 				struct hid_sensor_hub_device *hsdev,
214 				struct iio_chan_spec *channels,
215 				unsigned usage_id,
216 				struct als_state *st)
217 {
218 	int ret;
219 
220 	ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
221 			usage_id,
222 			HID_USAGE_SENSOR_LIGHT_ILLUM,
223 			&st->als_illum);
224 	if (ret < 0)
225 		return ret;
226 	als_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_ILLUM,
227 					st->als_illum.size);
228 
229 	dev_dbg(&pdev->dev, "als %x:%x\n", st->als_illum.index,
230 			st->als_illum.report_id);
231 
232 	/* Set Sensitivity field ids, when there is no individual modifier */
233 	if (st->common_attributes.sensitivity.index < 0) {
234 		sensor_hub_input_get_attribute_info(hsdev,
235 			HID_FEATURE_REPORT, usage_id,
236 			HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS |
237 			HID_USAGE_SENSOR_DATA_LIGHT,
238 			&st->common_attributes.sensitivity);
239 		dev_dbg(&pdev->dev, "Sensitivity index:report %d:%d\n",
240 			st->common_attributes.sensitivity.index,
241 			st->common_attributes.sensitivity.report_id);
242 	}
243 	return ret;
244 }
245 
246 /* Function to initialize the processing for usage id */
247 static int hid_als_probe(struct platform_device *pdev)
248 {
249 	int ret = 0;
250 	static const char *name = "als";
251 	struct iio_dev *indio_dev;
252 	struct als_state *als_state;
253 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
254 	struct iio_chan_spec *channels;
255 
256 	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(struct als_state));
257 	if (!indio_dev)
258 		return -ENOMEM;
259 	platform_set_drvdata(pdev, indio_dev);
260 
261 	als_state = iio_priv(indio_dev);
262 	als_state->common_attributes.hsdev = hsdev;
263 	als_state->common_attributes.pdev = pdev;
264 
265 	ret = hid_sensor_parse_common_attributes(hsdev, HID_USAGE_SENSOR_ALS,
266 					&als_state->common_attributes);
267 	if (ret) {
268 		dev_err(&pdev->dev, "failed to setup common attributes\n");
269 		return ret;
270 	}
271 
272 	channels = kmemdup(als_channels, sizeof(als_channels), GFP_KERNEL);
273 	if (!channels) {
274 		dev_err(&pdev->dev, "failed to duplicate channels\n");
275 		return -ENOMEM;
276 	}
277 
278 	ret = als_parse_report(pdev, hsdev, channels,
279 				HID_USAGE_SENSOR_ALS, als_state);
280 	if (ret) {
281 		dev_err(&pdev->dev, "failed to setup attributes\n");
282 		goto error_free_dev_mem;
283 	}
284 
285 	indio_dev->channels = channels;
286 	indio_dev->num_channels =
287 				ARRAY_SIZE(als_channels);
288 	indio_dev->dev.parent = &pdev->dev;
289 	indio_dev->info = &als_info;
290 	indio_dev->name = name;
291 	indio_dev->modes = INDIO_DIRECT_MODE;
292 
293 	ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
294 		NULL, NULL);
295 	if (ret) {
296 		dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
297 		goto error_free_dev_mem;
298 	}
299 	als_state->common_attributes.data_ready = false;
300 	ret = hid_sensor_setup_trigger(indio_dev, name,
301 				&als_state->common_attributes);
302 	if (ret < 0) {
303 		dev_err(&pdev->dev, "trigger setup failed\n");
304 		goto error_unreg_buffer_funcs;
305 	}
306 
307 	ret = iio_device_register(indio_dev);
308 	if (ret) {
309 		dev_err(&pdev->dev, "device register failed\n");
310 		goto error_remove_trigger;
311 	}
312 
313 	als_state->callbacks.send_event = als_proc_event;
314 	als_state->callbacks.capture_sample = als_capture_sample;
315 	als_state->callbacks.pdev = pdev;
316 	ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_ALS,
317 					&als_state->callbacks);
318 	if (ret < 0) {
319 		dev_err(&pdev->dev, "callback reg failed\n");
320 		goto error_iio_unreg;
321 	}
322 
323 	return ret;
324 
325 error_iio_unreg:
326 	iio_device_unregister(indio_dev);
327 error_remove_trigger:
328 	hid_sensor_remove_trigger(&als_state->common_attributes);
329 error_unreg_buffer_funcs:
330 	iio_triggered_buffer_cleanup(indio_dev);
331 error_free_dev_mem:
332 	kfree(indio_dev->channels);
333 	return ret;
334 }
335 
336 /* Function to deinitialize the processing for usage id */
337 static int hid_als_remove(struct platform_device *pdev)
338 {
339 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
340 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
341 	struct als_state *als_state = iio_priv(indio_dev);
342 
343 	sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_ALS);
344 	iio_device_unregister(indio_dev);
345 	hid_sensor_remove_trigger(&als_state->common_attributes);
346 	iio_triggered_buffer_cleanup(indio_dev);
347 	kfree(indio_dev->channels);
348 
349 	return 0;
350 }
351 
352 static struct platform_device_id hid_als_ids[] = {
353 	{
354 		/* Format: HID-SENSOR-usage_id_in_hex_lowercase */
355 		.name = "HID-SENSOR-200041",
356 	},
357 	{ /* sentinel */ }
358 };
359 MODULE_DEVICE_TABLE(platform, hid_als_ids);
360 
361 static struct platform_driver hid_als_platform_driver = {
362 	.id_table = hid_als_ids,
363 	.driver = {
364 		.name	= KBUILD_MODNAME,
365 		.owner	= THIS_MODULE,
366 	},
367 	.probe		= hid_als_probe,
368 	.remove		= hid_als_remove,
369 };
370 module_platform_driver(hid_als_platform_driver);
371 
372 MODULE_DESCRIPTION("HID Sensor ALS");
373 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@intel.com>");
374 MODULE_LICENSE("GPL");
375