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 /*Format: HID-SENSOR-usage_id_in_hex*/
34 /*Usage ID from spec for Accelerometer-3D: 0x200041*/
35 #define DRIVER_NAME "HID-SENSOR-200041"
36 
37 #define CHANNEL_SCAN_INDEX_ILLUM 0
38 
39 struct als_state {
40 	struct hid_sensor_hub_callbacks callbacks;
41 	struct hid_sensor_common common_attributes;
42 	struct hid_sensor_hub_attribute_info als_illum;
43 	u32 illum;
44 };
45 
46 /* Channel definitions */
47 static const struct iio_chan_spec als_channels[] = {
48 	{
49 		.type = IIO_INTENSITY,
50 		.modified = 1,
51 		.channel2 = IIO_MOD_LIGHT_BOTH,
52 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
53 		BIT(IIO_CHAN_INFO_SCALE) |
54 		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
55 		BIT(IIO_CHAN_INFO_HYSTERESIS),
56 		.scan_index = CHANNEL_SCAN_INDEX_ILLUM,
57 	}
58 };
59 
60 /* Adjust channel real bits based on report descriptor */
61 static void als_adjust_channel_bit_mask(struct iio_chan_spec *channels,
62 					int channel, int size)
63 {
64 	channels[channel].scan_type.sign = 's';
65 	/* Real storage bits will change based on the report desc. */
66 	channels[channel].scan_type.realbits = size * 8;
67 	/* Maximum size of a sample to capture is u32 */
68 	channels[channel].scan_type.storagebits = sizeof(u32) * 8;
69 }
70 
71 /* Channel read_raw handler */
72 static int als_read_raw(struct iio_dev *indio_dev,
73 			      struct iio_chan_spec const *chan,
74 			      int *val, int *val2,
75 			      long mask)
76 {
77 	struct als_state *als_state = iio_priv(indio_dev);
78 	int report_id = -1;
79 	u32 address;
80 	int ret;
81 	int ret_type;
82 
83 	*val = 0;
84 	*val2 = 0;
85 	switch (mask) {
86 	case 0:
87 		switch (chan->scan_index) {
88 		case  CHANNEL_SCAN_INDEX_ILLUM:
89 			report_id = als_state->als_illum.report_id;
90 			address =
91 			HID_USAGE_SENSOR_LIGHT_ILLUM;
92 			break;
93 		default:
94 			report_id = -1;
95 			break;
96 		}
97 		if (report_id >= 0)
98 			*val = sensor_hub_input_attr_get_raw_value(
99 				als_state->common_attributes.hsdev,
100 				HID_USAGE_SENSOR_ALS, address,
101 				report_id);
102 		else {
103 			*val = 0;
104 			return -EINVAL;
105 		}
106 		ret_type = IIO_VAL_INT;
107 		break;
108 	case IIO_CHAN_INFO_SCALE:
109 		*val = als_state->als_illum.units;
110 		ret_type = IIO_VAL_INT;
111 		break;
112 	case IIO_CHAN_INFO_OFFSET:
113 		*val = hid_sensor_convert_exponent(
114 				als_state->als_illum.unit_expo);
115 		ret_type = IIO_VAL_INT;
116 		break;
117 	case IIO_CHAN_INFO_SAMP_FREQ:
118 		ret = hid_sensor_read_samp_freq_value(
119 				&als_state->common_attributes, val, val2);
120 		ret_type = IIO_VAL_INT_PLUS_MICRO;
121 		break;
122 	case IIO_CHAN_INFO_HYSTERESIS:
123 		ret = hid_sensor_read_raw_hyst_value(
124 				&als_state->common_attributes, val, val2);
125 		ret_type = IIO_VAL_INT_PLUS_MICRO;
126 		break;
127 	default:
128 		ret_type = -EINVAL;
129 		break;
130 	}
131 
132 	return ret_type;
133 }
134 
135 /* Channel write_raw handler */
136 static int als_write_raw(struct iio_dev *indio_dev,
137 			       struct iio_chan_spec const *chan,
138 			       int val,
139 			       int val2,
140 			       long mask)
141 {
142 	struct als_state *als_state = iio_priv(indio_dev);
143 	int ret = 0;
144 
145 	switch (mask) {
146 	case IIO_CHAN_INFO_SAMP_FREQ:
147 		ret = hid_sensor_write_samp_freq_value(
148 				&als_state->common_attributes, val, val2);
149 		break;
150 	case IIO_CHAN_INFO_HYSTERESIS:
151 		ret = hid_sensor_write_raw_hyst_value(
152 				&als_state->common_attributes, val, val2);
153 		break;
154 	default:
155 		ret = -EINVAL;
156 	}
157 
158 	return ret;
159 }
160 
161 static int als_write_raw_get_fmt(struct iio_dev *indio_dev,
162 			       struct iio_chan_spec const *chan,
163 			       long mask)
164 {
165 	return IIO_VAL_INT_PLUS_MICRO;
166 }
167 
168 static const struct iio_info als_info = {
169 	.driver_module = THIS_MODULE,
170 	.read_raw = &als_read_raw,
171 	.write_raw = &als_write_raw,
172 	.write_raw_get_fmt = &als_write_raw_get_fmt,
173 };
174 
175 /* Function to push data to buffer */
176 static void hid_sensor_push_data(struct iio_dev *indio_dev, u8 *data, int len)
177 {
178 	dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n");
179 	iio_push_to_buffers(indio_dev, (u8 *)data);
180 }
181 
182 /* Callback handler to send event after all samples are received and captured */
183 static int als_proc_event(struct hid_sensor_hub_device *hsdev,
184 				unsigned usage_id,
185 				void *priv)
186 {
187 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
188 	struct als_state *als_state = iio_priv(indio_dev);
189 
190 	dev_dbg(&indio_dev->dev, "als_proc_event [%d]\n",
191 				als_state->common_attributes.data_ready);
192 	if (als_state->common_attributes.data_ready)
193 		hid_sensor_push_data(indio_dev,
194 				(u8 *)&als_state->illum,
195 				sizeof(als_state->illum));
196 
197 	return 0;
198 }
199 
200 /* Capture samples in local storage */
201 static int als_capture_sample(struct hid_sensor_hub_device *hsdev,
202 				unsigned usage_id,
203 				size_t raw_len, char *raw_data,
204 				void *priv)
205 {
206 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
207 	struct als_state *als_state = iio_priv(indio_dev);
208 	int ret = -EINVAL;
209 
210 	switch (usage_id) {
211 	case HID_USAGE_SENSOR_LIGHT_ILLUM:
212 		als_state->illum = *(u32 *)raw_data;
213 		ret = 0;
214 		break;
215 	default:
216 		break;
217 	}
218 
219 	return ret;
220 }
221 
222 /* Parse report which is specific to an usage id*/
223 static int als_parse_report(struct platform_device *pdev,
224 				struct hid_sensor_hub_device *hsdev,
225 				struct iio_chan_spec *channels,
226 				unsigned usage_id,
227 				struct als_state *st)
228 {
229 	int ret;
230 
231 	ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
232 			usage_id,
233 			HID_USAGE_SENSOR_LIGHT_ILLUM,
234 			&st->als_illum);
235 	if (ret < 0)
236 		return ret;
237 	als_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_ILLUM,
238 					st->als_illum.size);
239 
240 	dev_dbg(&pdev->dev, "als %x:%x\n", st->als_illum.index,
241 			st->als_illum.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 = iio_device_alloc(sizeof(struct als_state));
257 	if (indio_dev == NULL) {
258 		ret = -ENOMEM;
259 		goto error_ret;
260 	}
261 	platform_set_drvdata(pdev, indio_dev);
262 
263 	als_state = iio_priv(indio_dev);
264 	als_state->common_attributes.hsdev = hsdev;
265 	als_state->common_attributes.pdev = pdev;
266 
267 	ret = hid_sensor_parse_common_attributes(hsdev, HID_USAGE_SENSOR_ALS,
268 					&als_state->common_attributes);
269 	if (ret) {
270 		dev_err(&pdev->dev, "failed to setup common attributes\n");
271 		goto error_free_dev;
272 	}
273 
274 	channels = kmemdup(als_channels, sizeof(als_channels), GFP_KERNEL);
275 	if (!channels) {
276 		ret = -ENOMEM;
277 		dev_err(&pdev->dev, "failed to duplicate channels\n");
278 		goto error_free_dev;
279 	}
280 
281 	ret = als_parse_report(pdev, hsdev, channels,
282 				HID_USAGE_SENSOR_ALS, als_state);
283 	if (ret) {
284 		dev_err(&pdev->dev, "failed to setup attributes\n");
285 		goto error_free_dev_mem;
286 	}
287 
288 	indio_dev->channels = channels;
289 	indio_dev->num_channels =
290 				ARRAY_SIZE(als_channels);
291 	indio_dev->dev.parent = &pdev->dev;
292 	indio_dev->info = &als_info;
293 	indio_dev->name = name;
294 	indio_dev->modes = INDIO_DIRECT_MODE;
295 
296 	ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
297 		NULL, NULL);
298 	if (ret) {
299 		dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
300 		goto error_free_dev_mem;
301 	}
302 	als_state->common_attributes.data_ready = false;
303 	ret = hid_sensor_setup_trigger(indio_dev, name,
304 				&als_state->common_attributes);
305 	if (ret < 0) {
306 		dev_err(&pdev->dev, "trigger setup failed\n");
307 		goto error_unreg_buffer_funcs;
308 	}
309 
310 	ret = iio_device_register(indio_dev);
311 	if (ret) {
312 		dev_err(&pdev->dev, "device register failed\n");
313 		goto error_remove_trigger;
314 	}
315 
316 	als_state->callbacks.send_event = als_proc_event;
317 	als_state->callbacks.capture_sample = als_capture_sample;
318 	als_state->callbacks.pdev = pdev;
319 	ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_ALS,
320 					&als_state->callbacks);
321 	if (ret < 0) {
322 		dev_err(&pdev->dev, "callback reg failed\n");
323 		goto error_iio_unreg;
324 	}
325 
326 	return ret;
327 
328 error_iio_unreg:
329 	iio_device_unregister(indio_dev);
330 error_remove_trigger:
331 	hid_sensor_remove_trigger(indio_dev);
332 error_unreg_buffer_funcs:
333 	iio_triggered_buffer_cleanup(indio_dev);
334 error_free_dev_mem:
335 	kfree(indio_dev->channels);
336 error_free_dev:
337 	iio_device_free(indio_dev);
338 error_ret:
339 	return ret;
340 }
341 
342 /* Function to deinitialize the processing for usage id */
343 static int hid_als_remove(struct platform_device *pdev)
344 {
345 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
346 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
347 
348 	sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_ALS);
349 	iio_device_unregister(indio_dev);
350 	hid_sensor_remove_trigger(indio_dev);
351 	iio_triggered_buffer_cleanup(indio_dev);
352 	kfree(indio_dev->channels);
353 	iio_device_free(indio_dev);
354 
355 	return 0;
356 }
357 
358 static struct platform_driver hid_als_platform_driver = {
359 	.driver = {
360 		.name	= DRIVER_NAME,
361 		.owner	= THIS_MODULE,
362 	},
363 	.probe		= hid_als_probe,
364 	.remove		= hid_als_remove,
365 };
366 module_platform_driver(hid_als_platform_driver);
367 
368 MODULE_DESCRIPTION("HID Sensor ALS");
369 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@intel.com>");
370 MODULE_LICENSE("GPL");
371