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, u8 *data, int len)
165 {
166 	dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n");
167 	iio_push_to_buffers(indio_dev, (u8 *)data);
168 }
169 
170 /* Callback handler to send event after all samples are received and captured */
171 static int als_proc_event(struct hid_sensor_hub_device *hsdev,
172 				unsigned usage_id,
173 				void *priv)
174 {
175 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
176 	struct als_state *als_state = iio_priv(indio_dev);
177 
178 	dev_dbg(&indio_dev->dev, "als_proc_event [%d]\n",
179 				als_state->common_attributes.data_ready);
180 	if (als_state->common_attributes.data_ready)
181 		hid_sensor_push_data(indio_dev,
182 				(u8 *)&als_state->illum,
183 				sizeof(als_state->illum));
184 
185 	return 0;
186 }
187 
188 /* Capture samples in local storage */
189 static int als_capture_sample(struct hid_sensor_hub_device *hsdev,
190 				unsigned usage_id,
191 				size_t raw_len, char *raw_data,
192 				void *priv)
193 {
194 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
195 	struct als_state *als_state = iio_priv(indio_dev);
196 	int ret = -EINVAL;
197 
198 	switch (usage_id) {
199 	case HID_USAGE_SENSOR_LIGHT_ILLUM:
200 		als_state->illum = *(u32 *)raw_data;
201 		ret = 0;
202 		break;
203 	default:
204 		break;
205 	}
206 
207 	return ret;
208 }
209 
210 /* Parse report which is specific to an usage id*/
211 static int als_parse_report(struct platform_device *pdev,
212 				struct hid_sensor_hub_device *hsdev,
213 				struct iio_chan_spec *channels,
214 				unsigned usage_id,
215 				struct als_state *st)
216 {
217 	int ret;
218 
219 	ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
220 			usage_id,
221 			HID_USAGE_SENSOR_LIGHT_ILLUM,
222 			&st->als_illum);
223 	if (ret < 0)
224 		return ret;
225 	als_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_ILLUM,
226 					st->als_illum.size);
227 
228 	dev_dbg(&pdev->dev, "als %x:%x\n", st->als_illum.index,
229 			st->als_illum.report_id);
230 
231 	return ret;
232 }
233 
234 /* Function to initialize the processing for usage id */
235 static int hid_als_probe(struct platform_device *pdev)
236 {
237 	int ret = 0;
238 	static const char *name = "als";
239 	struct iio_dev *indio_dev;
240 	struct als_state *als_state;
241 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
242 	struct iio_chan_spec *channels;
243 
244 	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(struct als_state));
245 	if (!indio_dev)
246 		return -ENOMEM;
247 	platform_set_drvdata(pdev, indio_dev);
248 
249 	als_state = iio_priv(indio_dev);
250 	als_state->common_attributes.hsdev = hsdev;
251 	als_state->common_attributes.pdev = pdev;
252 
253 	ret = hid_sensor_parse_common_attributes(hsdev, HID_USAGE_SENSOR_ALS,
254 					&als_state->common_attributes);
255 	if (ret) {
256 		dev_err(&pdev->dev, "failed to setup common attributes\n");
257 		return ret;
258 	}
259 
260 	channels = kmemdup(als_channels, sizeof(als_channels), GFP_KERNEL);
261 	if (!channels) {
262 		dev_err(&pdev->dev, "failed to duplicate channels\n");
263 		return -ENOMEM;
264 	}
265 
266 	ret = als_parse_report(pdev, hsdev, channels,
267 				HID_USAGE_SENSOR_ALS, als_state);
268 	if (ret) {
269 		dev_err(&pdev->dev, "failed to setup attributes\n");
270 		goto error_free_dev_mem;
271 	}
272 
273 	indio_dev->channels = channels;
274 	indio_dev->num_channels =
275 				ARRAY_SIZE(als_channels);
276 	indio_dev->dev.parent = &pdev->dev;
277 	indio_dev->info = &als_info;
278 	indio_dev->name = name;
279 	indio_dev->modes = INDIO_DIRECT_MODE;
280 
281 	ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
282 		NULL, NULL);
283 	if (ret) {
284 		dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
285 		goto error_free_dev_mem;
286 	}
287 	als_state->common_attributes.data_ready = false;
288 	ret = hid_sensor_setup_trigger(indio_dev, name,
289 				&als_state->common_attributes);
290 	if (ret < 0) {
291 		dev_err(&pdev->dev, "trigger setup failed\n");
292 		goto error_unreg_buffer_funcs;
293 	}
294 
295 	ret = iio_device_register(indio_dev);
296 	if (ret) {
297 		dev_err(&pdev->dev, "device register failed\n");
298 		goto error_remove_trigger;
299 	}
300 
301 	als_state->callbacks.send_event = als_proc_event;
302 	als_state->callbacks.capture_sample = als_capture_sample;
303 	als_state->callbacks.pdev = pdev;
304 	ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_ALS,
305 					&als_state->callbacks);
306 	if (ret < 0) {
307 		dev_err(&pdev->dev, "callback reg failed\n");
308 		goto error_iio_unreg;
309 	}
310 
311 	return ret;
312 
313 error_iio_unreg:
314 	iio_device_unregister(indio_dev);
315 error_remove_trigger:
316 	hid_sensor_remove_trigger(indio_dev);
317 error_unreg_buffer_funcs:
318 	iio_triggered_buffer_cleanup(indio_dev);
319 error_free_dev_mem:
320 	kfree(indio_dev->channels);
321 	return ret;
322 }
323 
324 /* Function to deinitialize the processing for usage id */
325 static int hid_als_remove(struct platform_device *pdev)
326 {
327 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
328 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
329 
330 	sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_ALS);
331 	iio_device_unregister(indio_dev);
332 	hid_sensor_remove_trigger(indio_dev);
333 	iio_triggered_buffer_cleanup(indio_dev);
334 	kfree(indio_dev->channels);
335 
336 	return 0;
337 }
338 
339 static struct platform_device_id hid_als_ids[] = {
340 	{
341 		/* Format: HID-SENSOR-usage_id_in_hex_lowercase */
342 		.name = "HID-SENSOR-200041",
343 	},
344 	{ /* sentinel */ }
345 };
346 MODULE_DEVICE_TABLE(platform, hid_als_ids);
347 
348 static struct platform_driver hid_als_platform_driver = {
349 	.id_table = hid_als_ids,
350 	.driver = {
351 		.name	= KBUILD_MODNAME,
352 		.owner	= THIS_MODULE,
353 	},
354 	.probe		= hid_als_probe,
355 	.remove		= hid_als_remove,
356 };
357 module_platform_driver(hid_als_platform_driver);
358 
359 MODULE_DESCRIPTION("HID Sensor ALS");
360 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@intel.com>");
361 MODULE_LICENSE("GPL");
362