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