xref: /linux/drivers/iio/light/hid-sensor-als.c (revision ebf68996de0ab250c5d520eb2291ab65643e9a1e)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * HID Sensors Driver
4  * Copyright (c) 2012, Intel Corporation.
5  */
6 #include <linux/device.h>
7 #include <linux/platform_device.h>
8 #include <linux/module.h>
9 #include <linux/interrupt.h>
10 #include <linux/irq.h>
11 #include <linux/slab.h>
12 #include <linux/delay.h>
13 #include <linux/hid-sensor-hub.h>
14 #include <linux/iio/iio.h>
15 #include <linux/iio/sysfs.h>
16 #include <linux/iio/buffer.h>
17 #include <linux/iio/trigger_consumer.h>
18 #include <linux/iio/triggered_buffer.h>
19 #include "../common/hid-sensors/hid-sensor-trigger.h"
20 
21 enum {
22 	CHANNEL_SCAN_INDEX_INTENSITY = 0,
23 	CHANNEL_SCAN_INDEX_ILLUM = 1,
24 	CHANNEL_SCAN_INDEX_MAX
25 };
26 
27 struct als_state {
28 	struct hid_sensor_hub_callbacks callbacks;
29 	struct hid_sensor_common common_attributes;
30 	struct hid_sensor_hub_attribute_info als_illum;
31 	u32 illum[CHANNEL_SCAN_INDEX_MAX];
32 	int scale_pre_decml;
33 	int scale_post_decml;
34 	int scale_precision;
35 	int value_offset;
36 };
37 
38 /* Channel definitions */
39 static const struct iio_chan_spec als_channels[] = {
40 	{
41 		.type = IIO_INTENSITY,
42 		.modified = 1,
43 		.channel2 = IIO_MOD_LIGHT_BOTH,
44 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
45 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
46 		BIT(IIO_CHAN_INFO_SCALE) |
47 		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
48 		BIT(IIO_CHAN_INFO_HYSTERESIS),
49 		.scan_index = CHANNEL_SCAN_INDEX_INTENSITY,
50 	},
51 	{
52 		.type = IIO_LIGHT,
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 min;
84 
85 	*val = 0;
86 	*val2 = 0;
87 	switch (mask) {
88 	case IIO_CHAN_INFO_RAW:
89 		switch (chan->scan_index) {
90 		case  CHANNEL_SCAN_INDEX_INTENSITY:
91 		case  CHANNEL_SCAN_INDEX_ILLUM:
92 			report_id = als_state->als_illum.report_id;
93 			min = als_state->als_illum.logical_minimum;
94 			address = HID_USAGE_SENSOR_LIGHT_ILLUM;
95 			break;
96 		default:
97 			report_id = -1;
98 			break;
99 		}
100 		if (report_id >= 0) {
101 			hid_sensor_power_state(&als_state->common_attributes,
102 						true);
103 			*val = sensor_hub_input_attr_get_raw_value(
104 					als_state->common_attributes.hsdev,
105 					HID_USAGE_SENSOR_ALS, address,
106 					report_id,
107 					SENSOR_HUB_SYNC,
108 					min < 0);
109 			hid_sensor_power_state(&als_state->common_attributes,
110 						false);
111 		} else {
112 			*val = 0;
113 			return -EINVAL;
114 		}
115 		ret_type = IIO_VAL_INT;
116 		break;
117 	case IIO_CHAN_INFO_SCALE:
118 		*val = als_state->scale_pre_decml;
119 		*val2 = als_state->scale_post_decml;
120 		ret_type = als_state->scale_precision;
121 		break;
122 	case IIO_CHAN_INFO_OFFSET:
123 		*val = als_state->value_offset;
124 		ret_type = IIO_VAL_INT;
125 		break;
126 	case IIO_CHAN_INFO_SAMP_FREQ:
127 		ret_type = hid_sensor_read_samp_freq_value(
128 				&als_state->common_attributes, val, val2);
129 		break;
130 	case IIO_CHAN_INFO_HYSTERESIS:
131 		ret_type = hid_sensor_read_raw_hyst_value(
132 				&als_state->common_attributes, val, val2);
133 		break;
134 	default:
135 		ret_type = -EINVAL;
136 		break;
137 	}
138 
139 	return ret_type;
140 }
141 
142 /* Channel write_raw handler */
143 static int als_write_raw(struct iio_dev *indio_dev,
144 			       struct iio_chan_spec const *chan,
145 			       int val,
146 			       int val2,
147 			       long mask)
148 {
149 	struct als_state *als_state = iio_priv(indio_dev);
150 	int ret = 0;
151 
152 	switch (mask) {
153 	case IIO_CHAN_INFO_SAMP_FREQ:
154 		ret = hid_sensor_write_samp_freq_value(
155 				&als_state->common_attributes, val, val2);
156 		break;
157 	case IIO_CHAN_INFO_HYSTERESIS:
158 		ret = hid_sensor_write_raw_hyst_value(
159 				&als_state->common_attributes, val, val2);
160 		break;
161 	default:
162 		ret = -EINVAL;
163 	}
164 
165 	return ret;
166 }
167 
168 static const struct iio_info als_info = {
169 	.read_raw = &als_read_raw,
170 	.write_raw = &als_write_raw,
171 };
172 
173 /* Function to push data to buffer */
174 static void hid_sensor_push_data(struct iio_dev *indio_dev, const void *data,
175 					int len)
176 {
177 	dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n");
178 	iio_push_to_buffers(indio_dev, data);
179 }
180 
181 /* Callback handler to send event after all samples are received and captured */
182 static int als_proc_event(struct hid_sensor_hub_device *hsdev,
183 				unsigned usage_id,
184 				void *priv)
185 {
186 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
187 	struct als_state *als_state = iio_priv(indio_dev);
188 
189 	dev_dbg(&indio_dev->dev, "als_proc_event\n");
190 	if (atomic_read(&als_state->common_attributes.data_ready))
191 		hid_sensor_push_data(indio_dev,
192 				&als_state->illum,
193 				sizeof(als_state->illum));
194 
195 	return 0;
196 }
197 
198 /* Capture samples in local storage */
199 static int als_capture_sample(struct hid_sensor_hub_device *hsdev,
200 				unsigned usage_id,
201 				size_t raw_len, char *raw_data,
202 				void *priv)
203 {
204 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
205 	struct als_state *als_state = iio_priv(indio_dev);
206 	int ret = -EINVAL;
207 	u32 sample_data = *(u32 *)raw_data;
208 
209 	switch (usage_id) {
210 	case HID_USAGE_SENSOR_LIGHT_ILLUM:
211 		als_state->illum[CHANNEL_SCAN_INDEX_INTENSITY] = sample_data;
212 		als_state->illum[CHANNEL_SCAN_INDEX_ILLUM] = sample_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_INTENSITY,
238 				    st->als_illum.size);
239 	als_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_ILLUM,
240 					st->als_illum.size);
241 
242 	dev_dbg(&pdev->dev, "als %x:%x\n", st->als_illum.index,
243 			st->als_illum.report_id);
244 
245 	st->scale_precision = hid_sensor_format_scale(
246 				HID_USAGE_SENSOR_ALS,
247 				&st->als_illum,
248 				&st->scale_pre_decml, &st->scale_post_decml);
249 
250 	/* Set Sensitivity field ids, when there is no individual modifier */
251 	if (st->common_attributes.sensitivity.index < 0) {
252 		sensor_hub_input_get_attribute_info(hsdev,
253 			HID_FEATURE_REPORT, usage_id,
254 			HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS |
255 			HID_USAGE_SENSOR_DATA_LIGHT,
256 			&st->common_attributes.sensitivity);
257 		dev_dbg(&pdev->dev, "Sensitivity index:report %d:%d\n",
258 			st->common_attributes.sensitivity.index,
259 			st->common_attributes.sensitivity.report_id);
260 	}
261 	return ret;
262 }
263 
264 /* Function to initialize the processing for usage id */
265 static int hid_als_probe(struct platform_device *pdev)
266 {
267 	int ret = 0;
268 	static const char *name = "als";
269 	struct iio_dev *indio_dev;
270 	struct als_state *als_state;
271 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
272 
273 	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(struct als_state));
274 	if (!indio_dev)
275 		return -ENOMEM;
276 	platform_set_drvdata(pdev, indio_dev);
277 
278 	als_state = iio_priv(indio_dev);
279 	als_state->common_attributes.hsdev = hsdev;
280 	als_state->common_attributes.pdev = pdev;
281 
282 	ret = hid_sensor_parse_common_attributes(hsdev, HID_USAGE_SENSOR_ALS,
283 					&als_state->common_attributes);
284 	if (ret) {
285 		dev_err(&pdev->dev, "failed to setup common attributes\n");
286 		return ret;
287 	}
288 
289 	indio_dev->channels = kmemdup(als_channels,
290 				      sizeof(als_channels), GFP_KERNEL);
291 	if (!indio_dev->channels) {
292 		dev_err(&pdev->dev, "failed to duplicate channels\n");
293 		return -ENOMEM;
294 	}
295 
296 	ret = als_parse_report(pdev, hsdev,
297 			       (struct iio_chan_spec *)indio_dev->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->num_channels =
305 				ARRAY_SIZE(als_channels);
306 	indio_dev->dev.parent = &pdev->dev;
307 	indio_dev->info = &als_info;
308 	indio_dev->name = name;
309 	indio_dev->modes = INDIO_DIRECT_MODE;
310 
311 	ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
312 		NULL, NULL);
313 	if (ret) {
314 		dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
315 		goto error_free_dev_mem;
316 	}
317 	atomic_set(&als_state->common_attributes.data_ready, 0);
318 	ret = hid_sensor_setup_trigger(indio_dev, name,
319 				&als_state->common_attributes);
320 	if (ret < 0) {
321 		dev_err(&pdev->dev, "trigger setup failed\n");
322 		goto error_unreg_buffer_funcs;
323 	}
324 
325 	ret = iio_device_register(indio_dev);
326 	if (ret) {
327 		dev_err(&pdev->dev, "device register failed\n");
328 		goto error_remove_trigger;
329 	}
330 
331 	als_state->callbacks.send_event = als_proc_event;
332 	als_state->callbacks.capture_sample = als_capture_sample;
333 	als_state->callbacks.pdev = pdev;
334 	ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_ALS,
335 					&als_state->callbacks);
336 	if (ret < 0) {
337 		dev_err(&pdev->dev, "callback reg failed\n");
338 		goto error_iio_unreg;
339 	}
340 
341 	return ret;
342 
343 error_iio_unreg:
344 	iio_device_unregister(indio_dev);
345 error_remove_trigger:
346 	hid_sensor_remove_trigger(&als_state->common_attributes);
347 error_unreg_buffer_funcs:
348 	iio_triggered_buffer_cleanup(indio_dev);
349 error_free_dev_mem:
350 	kfree(indio_dev->channels);
351 	return ret;
352 }
353 
354 /* Function to deinitialize the processing for usage id */
355 static int hid_als_remove(struct platform_device *pdev)
356 {
357 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
358 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
359 	struct als_state *als_state = iio_priv(indio_dev);
360 
361 	sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_ALS);
362 	iio_device_unregister(indio_dev);
363 	hid_sensor_remove_trigger(&als_state->common_attributes);
364 	iio_triggered_buffer_cleanup(indio_dev);
365 	kfree(indio_dev->channels);
366 
367 	return 0;
368 }
369 
370 static const struct platform_device_id hid_als_ids[] = {
371 	{
372 		/* Format: HID-SENSOR-usage_id_in_hex_lowercase */
373 		.name = "HID-SENSOR-200041",
374 	},
375 	{ /* sentinel */ }
376 };
377 MODULE_DEVICE_TABLE(platform, hid_als_ids);
378 
379 static struct platform_driver hid_als_platform_driver = {
380 	.id_table = hid_als_ids,
381 	.driver = {
382 		.name	= KBUILD_MODNAME,
383 		.pm	= &hid_sensor_pm_ops,
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