xref: /linux/drivers/iio/pressure/hid-sensor-press.c (revision 23d66dbab84e8518943563df2ced14aaab28b77a)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * HID Sensors Driver
4  * Copyright (c) 2014, Intel Corporation.
5  */
6 #include <linux/bitops.h>
7 #include <linux/device.h>
8 #include <linux/platform_device.h>
9 #include <linux/module.h>
10 #include <linux/mod_devicetable.h>
11 #include <linux/slab.h>
12 #include <linux/hid-sensor-hub.h>
13 #include <linux/iio/iio.h>
14 #include <linux/iio/buffer.h>
15 #include "../common/hid-sensors/hid-sensor-trigger.h"
16 
17 enum {
18 	CHANNEL_SCAN_INDEX_PRESSURE,
19 	CHANNEL_SCAN_INDEX_TIMESTAMP,
20 };
21 
22 struct press_state {
23 	struct hid_sensor_hub_callbacks callbacks;
24 	struct hid_sensor_common common_attributes;
25 	struct hid_sensor_hub_attribute_info press_attr;
26 	struct {
27 		u32 press_data;
28 		aligned_s64 timestamp;
29 	} scan;
30 	int scale_pre_decml;
31 	int scale_post_decml;
32 	int scale_precision;
33 	int value_offset;
34 	s64 timestamp;
35 };
36 
37 static const u32 press_sensitivity_addresses[] = {
38 	HID_USAGE_SENSOR_DATA_ATMOSPHERIC_PRESSURE,
39 	HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE
40 };
41 
42 /* Channel definitions */
43 static const struct iio_chan_spec press_channels[] = {
44 	{
45 		.type = IIO_PRESSURE,
46 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
47 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
48 		BIT(IIO_CHAN_INFO_SCALE) |
49 		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
50 		BIT(IIO_CHAN_INFO_HYSTERESIS),
51 		.scan_index = CHANNEL_SCAN_INDEX_PRESSURE,
52 	},
53 	IIO_CHAN_SOFT_TIMESTAMP(CHANNEL_SCAN_INDEX_TIMESTAMP)
54 
55 };
56 
57 /* Channel read_raw handler */
58 static int press_read_raw(struct iio_dev *indio_dev,
59 			      struct iio_chan_spec const *chan,
60 			      int *val, int *val2,
61 			      long mask)
62 {
63 	struct press_state *press_state = iio_priv(indio_dev);
64 	int report_id = -1;
65 	u32 address;
66 	int ret_type;
67 	s32 min;
68 
69 	*val = 0;
70 	*val2 = 0;
71 	switch (mask) {
72 	case IIO_CHAN_INFO_RAW:
73 		switch (chan->scan_index) {
74 		case  CHANNEL_SCAN_INDEX_PRESSURE:
75 			report_id = press_state->press_attr.report_id;
76 			min = press_state->press_attr.logical_minimum;
77 			address = HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE;
78 			break;
79 		default:
80 			report_id = -1;
81 			break;
82 		}
83 		if (report_id >= 0) {
84 			hid_sensor_power_state(&press_state->common_attributes,
85 						true);
86 			*val = sensor_hub_input_attr_get_raw_value(
87 				press_state->common_attributes.hsdev,
88 				HID_USAGE_SENSOR_PRESSURE, address,
89 				report_id,
90 				SENSOR_HUB_SYNC,
91 				min < 0);
92 			hid_sensor_power_state(&press_state->common_attributes,
93 						false);
94 		} else {
95 			*val = 0;
96 			return -EINVAL;
97 		}
98 		ret_type = IIO_VAL_INT;
99 		break;
100 	case IIO_CHAN_INFO_SCALE:
101 		*val = press_state->scale_pre_decml;
102 		*val2 = press_state->scale_post_decml;
103 		ret_type = press_state->scale_precision;
104 		break;
105 	case IIO_CHAN_INFO_OFFSET:
106 		*val = press_state->value_offset;
107 		ret_type = IIO_VAL_INT;
108 		break;
109 	case IIO_CHAN_INFO_SAMP_FREQ:
110 		ret_type = hid_sensor_read_samp_freq_value(
111 				&press_state->common_attributes, val, val2);
112 		break;
113 	case IIO_CHAN_INFO_HYSTERESIS:
114 		ret_type = hid_sensor_read_raw_hyst_value(
115 				&press_state->common_attributes, val, val2);
116 		break;
117 	default:
118 		ret_type = -EINVAL;
119 		break;
120 	}
121 
122 	return ret_type;
123 }
124 
125 /* Channel write_raw handler */
126 static int press_write_raw(struct iio_dev *indio_dev,
127 			       struct iio_chan_spec const *chan,
128 			       int val,
129 			       int val2,
130 			       long mask)
131 {
132 	struct press_state *press_state = iio_priv(indio_dev);
133 	int ret = 0;
134 
135 	switch (mask) {
136 	case IIO_CHAN_INFO_SAMP_FREQ:
137 		ret = hid_sensor_write_samp_freq_value(
138 				&press_state->common_attributes, val, val2);
139 		break;
140 	case IIO_CHAN_INFO_HYSTERESIS:
141 		ret = hid_sensor_write_raw_hyst_value(
142 				&press_state->common_attributes, val, val2);
143 		break;
144 	default:
145 		ret = -EINVAL;
146 	}
147 
148 	return ret;
149 }
150 
151 static const struct iio_info press_info = {
152 	.read_raw = &press_read_raw,
153 	.write_raw = &press_write_raw,
154 };
155 
156 /* Callback handler to send event after all samples are received and captured */
157 static int press_proc_event(struct hid_sensor_hub_device *hsdev,
158 				unsigned usage_id,
159 				void *priv)
160 {
161 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
162 	struct press_state *press_state = iio_priv(indio_dev);
163 
164 	dev_dbg(&indio_dev->dev, "press_proc_event\n");
165 	if (atomic_read(&press_state->common_attributes.data_ready)) {
166 		if (!press_state->timestamp)
167 			press_state->timestamp = iio_get_time_ns(indio_dev);
168 
169 		iio_push_to_buffers_with_ts(indio_dev, &press_state->scan,
170 					    sizeof(press_state->scan),
171 					    press_state->timestamp);
172 	}
173 
174 	return 0;
175 }
176 
177 /* Capture samples in local storage */
178 static int press_capture_sample(struct hid_sensor_hub_device *hsdev,
179 				unsigned usage_id,
180 				size_t raw_len, char *raw_data,
181 				void *priv)
182 {
183 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
184 	struct press_state *press_state = iio_priv(indio_dev);
185 	int ret = -EINVAL;
186 
187 	switch (usage_id) {
188 	case HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE:
189 		press_state->scan.press_data = *(u32 *)raw_data;
190 		ret = 0;
191 		break;
192 	case HID_USAGE_SENSOR_TIME_TIMESTAMP:
193 		press_state->timestamp = hid_sensor_convert_timestamp(
194 			&press_state->common_attributes, *(s64 *)raw_data);
195 		break;
196 	default:
197 		break;
198 	}
199 
200 	return ret;
201 }
202 
203 /* Parse report which is specific to an usage id*/
204 static int press_parse_report(struct platform_device *pdev,
205 				struct hid_sensor_hub_device *hsdev,
206 				struct iio_chan_spec *channels,
207 				unsigned usage_id,
208 				struct press_state *st)
209 {
210 	int ret;
211 
212 	ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
213 			usage_id,
214 			HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE,
215 			&st->press_attr);
216 	if (ret < 0)
217 		return ret;
218 	channels[CHANNEL_SCAN_INDEX_PRESSURE].scan_type = (struct iio_scan_type) {
219 		.format = 's',
220 		.realbits = BYTES_TO_BITS(st->press_attr.size),
221 		.storagebits = BITS_PER_TYPE(u32),
222 	};
223 
224 	dev_dbg(&pdev->dev, "press %x:%x\n", st->press_attr.index,
225 			st->press_attr.report_id);
226 
227 	st->scale_precision = hid_sensor_format_scale(
228 				HID_USAGE_SENSOR_PRESSURE,
229 				&st->press_attr,
230 				&st->scale_pre_decml, &st->scale_post_decml);
231 
232 	return ret;
233 }
234 
235 /* Function to initialize the processing for usage id */
236 static int hid_press_probe(struct platform_device *pdev)
237 {
238 	struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);
239 	int ret = 0;
240 	static const char *name = "press";
241 	struct iio_dev *indio_dev;
242 	struct press_state *press_state;
243 
244 	indio_dev = devm_iio_device_alloc(&pdev->dev,
245 				sizeof(struct press_state));
246 	if (!indio_dev)
247 		return -ENOMEM;
248 	platform_set_drvdata(pdev, indio_dev);
249 
250 	press_state = iio_priv(indio_dev);
251 	press_state->common_attributes.hsdev = hsdev;
252 	press_state->common_attributes.pdev = pdev;
253 
254 	ret = hid_sensor_parse_common_attributes(hsdev,
255 					HID_USAGE_SENSOR_PRESSURE,
256 					&press_state->common_attributes,
257 					press_sensitivity_addresses,
258 					ARRAY_SIZE(press_sensitivity_addresses));
259 	if (ret) {
260 		dev_err(&pdev->dev, "failed to setup common attributes\n");
261 		return ret;
262 	}
263 
264 	indio_dev->channels = devm_kmemdup(&pdev->dev, press_channels,
265 					   sizeof(press_channels), GFP_KERNEL);
266 	if (!indio_dev->channels) {
267 		dev_err(&pdev->dev, "failed to duplicate channels\n");
268 		return -ENOMEM;
269 	}
270 
271 	ret = press_parse_report(pdev, hsdev,
272 				 (struct iio_chan_spec *)indio_dev->channels,
273 				 HID_USAGE_SENSOR_PRESSURE, press_state);
274 	if (ret) {
275 		dev_err(&pdev->dev, "failed to setup attributes\n");
276 		return ret;
277 	}
278 
279 	indio_dev->num_channels =
280 				ARRAY_SIZE(press_channels);
281 	indio_dev->info = &press_info;
282 	indio_dev->name = name;
283 	indio_dev->modes = INDIO_DIRECT_MODE;
284 
285 	atomic_set(&press_state->common_attributes.data_ready, 0);
286 
287 	ret = hid_sensor_setup_trigger(indio_dev, name,
288 				&press_state->common_attributes);
289 	if (ret) {
290 		dev_err(&pdev->dev, "trigger setup failed\n");
291 		return ret;
292 	}
293 
294 	ret = iio_device_register(indio_dev);
295 	if (ret) {
296 		dev_err(&pdev->dev, "device register failed\n");
297 		goto error_remove_trigger;
298 	}
299 
300 	press_state->callbacks.send_event = press_proc_event;
301 	press_state->callbacks.capture_sample = press_capture_sample;
302 	press_state->callbacks.pdev = pdev;
303 	ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_PRESSURE,
304 					&press_state->callbacks);
305 	if (ret < 0) {
306 		dev_err(&pdev->dev, "callback reg failed\n");
307 		goto error_iio_unreg;
308 	}
309 
310 	return ret;
311 
312 error_iio_unreg:
313 	iio_device_unregister(indio_dev);
314 error_remove_trigger:
315 	hid_sensor_remove_trigger(indio_dev, &press_state->common_attributes);
316 	return ret;
317 }
318 
319 /* Function to deinitialize the processing for usage id */
320 static void hid_press_remove(struct platform_device *pdev)
321 {
322 	struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);
323 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
324 	struct press_state *press_state = iio_priv(indio_dev);
325 
326 	sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_PRESSURE);
327 	iio_device_unregister(indio_dev);
328 	hid_sensor_remove_trigger(indio_dev, &press_state->common_attributes);
329 }
330 
331 static const struct platform_device_id hid_press_ids[] = {
332 	{
333 		/* Format: HID-SENSOR-usage_id_in_hex_lowercase */
334 		.name = "HID-SENSOR-200031",
335 	},
336 	{ }
337 };
338 MODULE_DEVICE_TABLE(platform, hid_press_ids);
339 
340 static struct platform_driver hid_press_platform_driver = {
341 	.id_table = hid_press_ids,
342 	.driver = {
343 		.name	= KBUILD_MODNAME,
344 		.pm	= &hid_sensor_pm_ops,
345 	},
346 	.probe		= hid_press_probe,
347 	.remove		= hid_press_remove,
348 };
349 module_platform_driver(hid_press_platform_driver);
350 
351 MODULE_DESCRIPTION("HID Sensor Pressure");
352 MODULE_AUTHOR("Archana Patni <archana.patni@intel.com>");
353 MODULE_LICENSE("GPL");
354 MODULE_IMPORT_NS("IIO_HID");
355