1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * HID Sensors Driver
4  * Copyright (c) 2014, Intel Corporation.
5  */
6 #include <linux/device.h>
7 #include <linux/platform_device.h>
8 #include <linux/module.h>
9 #include <linux/mod_devicetable.h>
10 #include <linux/slab.h>
11 #include <linux/hid-sensor-hub.h>
12 #include <linux/iio/iio.h>
13 #include <linux/iio/buffer.h>
14 #include "../common/hid-sensors/hid-sensor-trigger.h"
15 
16 enum {
17 	CHANNEL_SCAN_INDEX_PRESSURE,
18 	CHANNEL_SCAN_INDEX_TIMESTAMP,
19 };
20 
21 struct press_state {
22 	struct hid_sensor_hub_callbacks callbacks;
23 	struct hid_sensor_common common_attributes;
24 	struct hid_sensor_hub_attribute_info press_attr;
25 	struct {
26 		u32 press_data;
27 		u64 timestamp __aligned(8);
28 	} scan;
29 	int scale_pre_decml;
30 	int scale_post_decml;
31 	int scale_precision;
32 	int value_offset;
33 	s64 timestamp;
34 };
35 
36 static const u32 press_sensitivity_addresses[] = {
37 	HID_USAGE_SENSOR_DATA_ATMOSPHERIC_PRESSURE,
38 	HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE
39 };
40 
41 /* Channel definitions */
42 static const struct iio_chan_spec press_channels[] = {
43 	{
44 		.type = IIO_PRESSURE,
45 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
46 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
47 		BIT(IIO_CHAN_INFO_SCALE) |
48 		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
49 		BIT(IIO_CHAN_INFO_HYSTERESIS),
50 		.scan_index = CHANNEL_SCAN_INDEX_PRESSURE,
51 	},
52 	IIO_CHAN_SOFT_TIMESTAMP(CHANNEL_SCAN_INDEX_TIMESTAMP)
53 
54 };
55 
56 /* Adjust channel real bits based on report descriptor */
57 static void press_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 press_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 press_state *press_state = iio_priv(indio_dev);
74 	int report_id = -1;
75 	u32 address;
76 	int ret_type;
77 	s32 min;
78 
79 	*val = 0;
80 	*val2 = 0;
81 	switch (mask) {
82 	case IIO_CHAN_INFO_RAW:
83 		switch (chan->scan_index) {
84 		case  CHANNEL_SCAN_INDEX_PRESSURE:
85 			report_id = press_state->press_attr.report_id;
86 			min = press_state->press_attr.logical_minimum;
87 			address = HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE;
88 			break;
89 		default:
90 			report_id = -1;
91 			break;
92 		}
93 		if (report_id >= 0) {
94 			hid_sensor_power_state(&press_state->common_attributes,
95 						true);
96 			*val = sensor_hub_input_attr_get_raw_value(
97 				press_state->common_attributes.hsdev,
98 				HID_USAGE_SENSOR_PRESSURE, address,
99 				report_id,
100 				SENSOR_HUB_SYNC,
101 				min < 0);
102 			hid_sensor_power_state(&press_state->common_attributes,
103 						false);
104 		} else {
105 			*val = 0;
106 			return -EINVAL;
107 		}
108 		ret_type = IIO_VAL_INT;
109 		break;
110 	case IIO_CHAN_INFO_SCALE:
111 		*val = press_state->scale_pre_decml;
112 		*val2 = press_state->scale_post_decml;
113 		ret_type = press_state->scale_precision;
114 		break;
115 	case IIO_CHAN_INFO_OFFSET:
116 		*val = press_state->value_offset;
117 		ret_type = IIO_VAL_INT;
118 		break;
119 	case IIO_CHAN_INFO_SAMP_FREQ:
120 		ret_type = hid_sensor_read_samp_freq_value(
121 				&press_state->common_attributes, val, val2);
122 		break;
123 	case IIO_CHAN_INFO_HYSTERESIS:
124 		ret_type = hid_sensor_read_raw_hyst_value(
125 				&press_state->common_attributes, val, val2);
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 press_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 press_state *press_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 				&press_state->common_attributes, val, val2);
149 		break;
150 	case IIO_CHAN_INFO_HYSTERESIS:
151 		ret = hid_sensor_write_raw_hyst_value(
152 				&press_state->common_attributes, val, val2);
153 		break;
154 	default:
155 		ret = -EINVAL;
156 	}
157 
158 	return ret;
159 }
160 
161 static const struct iio_info press_info = {
162 	.read_raw = &press_read_raw,
163 	.write_raw = &press_write_raw,
164 };
165 
166 /* Callback handler to send event after all samples are received and captured */
167 static int press_proc_event(struct hid_sensor_hub_device *hsdev,
168 				unsigned usage_id,
169 				void *priv)
170 {
171 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
172 	struct press_state *press_state = iio_priv(indio_dev);
173 
174 	dev_dbg(&indio_dev->dev, "press_proc_event\n");
175 	if (atomic_read(&press_state->common_attributes.data_ready)) {
176 		if (!press_state->timestamp)
177 			press_state->timestamp = iio_get_time_ns(indio_dev);
178 
179 		iio_push_to_buffers_with_timestamp(
180 			indio_dev, &press_state->scan, press_state->timestamp);
181 	}
182 
183 	return 0;
184 }
185 
186 /* Capture samples in local storage */
187 static int press_capture_sample(struct hid_sensor_hub_device *hsdev,
188 				unsigned usage_id,
189 				size_t raw_len, char *raw_data,
190 				void *priv)
191 {
192 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
193 	struct press_state *press_state = iio_priv(indio_dev);
194 	int ret = -EINVAL;
195 
196 	switch (usage_id) {
197 	case HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE:
198 		press_state->scan.press_data = *(u32 *)raw_data;
199 		ret = 0;
200 		break;
201 	case HID_USAGE_SENSOR_TIME_TIMESTAMP:
202 		press_state->timestamp = hid_sensor_convert_timestamp(
203 			&press_state->common_attributes, *(s64 *)raw_data);
204 		break;
205 	default:
206 		break;
207 	}
208 
209 	return ret;
210 }
211 
212 /* Parse report which is specific to an usage id*/
213 static int press_parse_report(struct platform_device *pdev,
214 				struct hid_sensor_hub_device *hsdev,
215 				struct iio_chan_spec *channels,
216 				unsigned usage_id,
217 				struct press_state *st)
218 {
219 	int ret;
220 
221 	ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
222 			usage_id,
223 			HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE,
224 			&st->press_attr);
225 	if (ret < 0)
226 		return ret;
227 	press_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_PRESSURE,
228 					st->press_attr.size);
229 
230 	dev_dbg(&pdev->dev, "press %x:%x\n", st->press_attr.index,
231 			st->press_attr.report_id);
232 
233 	st->scale_precision = hid_sensor_format_scale(
234 				HID_USAGE_SENSOR_PRESSURE,
235 				&st->press_attr,
236 				&st->scale_pre_decml, &st->scale_post_decml);
237 
238 	return ret;
239 }
240 
241 /* Function to initialize the processing for usage id */
242 static int hid_press_probe(struct platform_device *pdev)
243 {
244 	int ret = 0;
245 	static const char *name = "press";
246 	struct iio_dev *indio_dev;
247 	struct press_state *press_state;
248 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
249 
250 	indio_dev = devm_iio_device_alloc(&pdev->dev,
251 				sizeof(struct press_state));
252 	if (!indio_dev)
253 		return -ENOMEM;
254 	platform_set_drvdata(pdev, indio_dev);
255 
256 	press_state = iio_priv(indio_dev);
257 	press_state->common_attributes.hsdev = hsdev;
258 	press_state->common_attributes.pdev = pdev;
259 
260 	ret = hid_sensor_parse_common_attributes(hsdev,
261 					HID_USAGE_SENSOR_PRESSURE,
262 					&press_state->common_attributes,
263 					press_sensitivity_addresses,
264 					ARRAY_SIZE(press_sensitivity_addresses));
265 	if (ret) {
266 		dev_err(&pdev->dev, "failed to setup common attributes\n");
267 		return ret;
268 	}
269 
270 	indio_dev->channels = devm_kmemdup(&pdev->dev, press_channels,
271 					   sizeof(press_channels), GFP_KERNEL);
272 	if (!indio_dev->channels) {
273 		dev_err(&pdev->dev, "failed to duplicate channels\n");
274 		return -ENOMEM;
275 	}
276 
277 	ret = press_parse_report(pdev, hsdev,
278 				 (struct iio_chan_spec *)indio_dev->channels,
279 				 HID_USAGE_SENSOR_PRESSURE, press_state);
280 	if (ret) {
281 		dev_err(&pdev->dev, "failed to setup attributes\n");
282 		return ret;
283 	}
284 
285 	indio_dev->num_channels =
286 				ARRAY_SIZE(press_channels);
287 	indio_dev->info = &press_info;
288 	indio_dev->name = name;
289 	indio_dev->modes = INDIO_DIRECT_MODE;
290 
291 	atomic_set(&press_state->common_attributes.data_ready, 0);
292 
293 	ret = hid_sensor_setup_trigger(indio_dev, name,
294 				&press_state->common_attributes);
295 	if (ret) {
296 		dev_err(&pdev->dev, "trigger setup failed\n");
297 		return ret;
298 	}
299 
300 	ret = iio_device_register(indio_dev);
301 	if (ret) {
302 		dev_err(&pdev->dev, "device register failed\n");
303 		goto error_remove_trigger;
304 	}
305 
306 	press_state->callbacks.send_event = press_proc_event;
307 	press_state->callbacks.capture_sample = press_capture_sample;
308 	press_state->callbacks.pdev = pdev;
309 	ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_PRESSURE,
310 					&press_state->callbacks);
311 	if (ret < 0) {
312 		dev_err(&pdev->dev, "callback reg failed\n");
313 		goto error_iio_unreg;
314 	}
315 
316 	return ret;
317 
318 error_iio_unreg:
319 	iio_device_unregister(indio_dev);
320 error_remove_trigger:
321 	hid_sensor_remove_trigger(indio_dev, &press_state->common_attributes);
322 	return ret;
323 }
324 
325 /* Function to deinitialize the processing for usage id */
326 static int hid_press_remove(struct platform_device *pdev)
327 {
328 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
329 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
330 	struct press_state *press_state = iio_priv(indio_dev);
331 
332 	sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_PRESSURE);
333 	iio_device_unregister(indio_dev);
334 	hid_sensor_remove_trigger(indio_dev, &press_state->common_attributes);
335 
336 	return 0;
337 }
338 
339 static const struct platform_device_id hid_press_ids[] = {
340 	{
341 		/* Format: HID-SENSOR-usage_id_in_hex_lowercase */
342 		.name = "HID-SENSOR-200031",
343 	},
344 	{ /* sentinel */ }
345 };
346 MODULE_DEVICE_TABLE(platform, hid_press_ids);
347 
348 static struct platform_driver hid_press_platform_driver = {
349 	.id_table = hid_press_ids,
350 	.driver = {
351 		.name	= KBUILD_MODNAME,
352 		.pm	= &hid_sensor_pm_ops,
353 	},
354 	.probe		= hid_press_probe,
355 	.remove		= hid_press_remove,
356 };
357 module_platform_driver(hid_press_platform_driver);
358 
359 MODULE_DESCRIPTION("HID Sensor Pressure");
360 MODULE_AUTHOR("Archana Patni <archana.patni@intel.com>");
361 MODULE_LICENSE("GPL");
362 MODULE_IMPORT_NS(IIO_HID);
363