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/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 "../common/hid-sensors/hid-sensor-trigger.h"
18 
19 #define CHANNEL_SCAN_INDEX_PRESSURE 0
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 	u32 press_data;
26 	int scale_pre_decml;
27 	int scale_post_decml;
28 	int scale_precision;
29 	int value_offset;
30 };
31 
32 /* Channel definitions */
33 static const struct iio_chan_spec press_channels[] = {
34 	{
35 		.type = IIO_PRESSURE,
36 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
37 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
38 		BIT(IIO_CHAN_INFO_SCALE) |
39 		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
40 		BIT(IIO_CHAN_INFO_HYSTERESIS),
41 		.scan_index = CHANNEL_SCAN_INDEX_PRESSURE,
42 	}
43 };
44 
45 /* Adjust channel real bits based on report descriptor */
46 static void press_adjust_channel_bit_mask(struct iio_chan_spec *channels,
47 					int channel, int size)
48 {
49 	channels[channel].scan_type.sign = 's';
50 	/* Real storage bits will change based on the report desc. */
51 	channels[channel].scan_type.realbits = size * 8;
52 	/* Maximum size of a sample to capture is u32 */
53 	channels[channel].scan_type.storagebits = sizeof(u32) * 8;
54 }
55 
56 /* Channel read_raw handler */
57 static int press_read_raw(struct iio_dev *indio_dev,
58 			      struct iio_chan_spec const *chan,
59 			      int *val, int *val2,
60 			      long mask)
61 {
62 	struct press_state *press_state = iio_priv(indio_dev);
63 	int report_id = -1;
64 	u32 address;
65 	int ret_type;
66 	s32 min;
67 
68 	*val = 0;
69 	*val2 = 0;
70 	switch (mask) {
71 	case IIO_CHAN_INFO_RAW:
72 		switch (chan->scan_index) {
73 		case  CHANNEL_SCAN_INDEX_PRESSURE:
74 			report_id = press_state->press_attr.report_id;
75 			min = press_state->press_attr.logical_minimum;
76 			address = HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE;
77 			break;
78 		default:
79 			report_id = -1;
80 			break;
81 		}
82 		if (report_id >= 0) {
83 			hid_sensor_power_state(&press_state->common_attributes,
84 						true);
85 			*val = sensor_hub_input_attr_get_raw_value(
86 				press_state->common_attributes.hsdev,
87 				HID_USAGE_SENSOR_PRESSURE, address,
88 				report_id,
89 				SENSOR_HUB_SYNC,
90 				min < 0);
91 			hid_sensor_power_state(&press_state->common_attributes,
92 						false);
93 		} else {
94 			*val = 0;
95 			return -EINVAL;
96 		}
97 		ret_type = IIO_VAL_INT;
98 		break;
99 	case IIO_CHAN_INFO_SCALE:
100 		*val = press_state->scale_pre_decml;
101 		*val2 = press_state->scale_post_decml;
102 		ret_type = press_state->scale_precision;
103 		break;
104 	case IIO_CHAN_INFO_OFFSET:
105 		*val = press_state->value_offset;
106 		ret_type = IIO_VAL_INT;
107 		break;
108 	case IIO_CHAN_INFO_SAMP_FREQ:
109 		ret_type = hid_sensor_read_samp_freq_value(
110 				&press_state->common_attributes, val, val2);
111 		break;
112 	case IIO_CHAN_INFO_HYSTERESIS:
113 		ret_type = hid_sensor_read_raw_hyst_value(
114 				&press_state->common_attributes, val, val2);
115 		break;
116 	default:
117 		ret_type = -EINVAL;
118 		break;
119 	}
120 
121 	return ret_type;
122 }
123 
124 /* Channel write_raw handler */
125 static int press_write_raw(struct iio_dev *indio_dev,
126 			       struct iio_chan_spec const *chan,
127 			       int val,
128 			       int val2,
129 			       long mask)
130 {
131 	struct press_state *press_state = iio_priv(indio_dev);
132 	int ret = 0;
133 
134 	switch (mask) {
135 	case IIO_CHAN_INFO_SAMP_FREQ:
136 		ret = hid_sensor_write_samp_freq_value(
137 				&press_state->common_attributes, val, val2);
138 		break;
139 	case IIO_CHAN_INFO_HYSTERESIS:
140 		ret = hid_sensor_write_raw_hyst_value(
141 				&press_state->common_attributes, val, val2);
142 		break;
143 	default:
144 		ret = -EINVAL;
145 	}
146 
147 	return ret;
148 }
149 
150 static const struct iio_info press_info = {
151 	.read_raw = &press_read_raw,
152 	.write_raw = &press_write_raw,
153 };
154 
155 /* Function to push data to buffer */
156 static void hid_sensor_push_data(struct iio_dev *indio_dev, const void *data,
157 					int len)
158 {
159 	dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n");
160 	iio_push_to_buffers(indio_dev, data);
161 }
162 
163 /* Callback handler to send event after all samples are received and captured */
164 static int press_proc_event(struct hid_sensor_hub_device *hsdev,
165 				unsigned usage_id,
166 				void *priv)
167 {
168 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
169 	struct press_state *press_state = iio_priv(indio_dev);
170 
171 	dev_dbg(&indio_dev->dev, "press_proc_event\n");
172 	if (atomic_read(&press_state->common_attributes.data_ready))
173 		hid_sensor_push_data(indio_dev,
174 				&press_state->press_data,
175 				sizeof(press_state->press_data));
176 
177 	return 0;
178 }
179 
180 /* Capture samples in local storage */
181 static int press_capture_sample(struct hid_sensor_hub_device *hsdev,
182 				unsigned usage_id,
183 				size_t raw_len, char *raw_data,
184 				void *priv)
185 {
186 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
187 	struct press_state *press_state = iio_priv(indio_dev);
188 	int ret = -EINVAL;
189 
190 	switch (usage_id) {
191 	case HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE:
192 		press_state->press_data = *(u32 *)raw_data;
193 		ret = 0;
194 		break;
195 	default:
196 		break;
197 	}
198 
199 	return ret;
200 }
201 
202 /* Parse report which is specific to an usage id*/
203 static int press_parse_report(struct platform_device *pdev,
204 				struct hid_sensor_hub_device *hsdev,
205 				struct iio_chan_spec *channels,
206 				unsigned usage_id,
207 				struct press_state *st)
208 {
209 	int ret;
210 
211 	ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
212 			usage_id,
213 			HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE,
214 			&st->press_attr);
215 	if (ret < 0)
216 		return ret;
217 	press_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_PRESSURE,
218 					st->press_attr.size);
219 
220 	dev_dbg(&pdev->dev, "press %x:%x\n", st->press_attr.index,
221 			st->press_attr.report_id);
222 
223 	st->scale_precision = hid_sensor_format_scale(
224 				HID_USAGE_SENSOR_PRESSURE,
225 				&st->press_attr,
226 				&st->scale_pre_decml, &st->scale_post_decml);
227 
228 	/* Set Sensitivity field ids, when there is no individual modifier */
229 	if (st->common_attributes.sensitivity.index < 0) {
230 		sensor_hub_input_get_attribute_info(hsdev,
231 			HID_FEATURE_REPORT, usage_id,
232 			HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS |
233 			HID_USAGE_SENSOR_DATA_ATMOSPHERIC_PRESSURE,
234 			&st->common_attributes.sensitivity);
235 		dev_dbg(&pdev->dev, "Sensitivity index:report %d:%d\n",
236 			st->common_attributes.sensitivity.index,
237 			st->common_attributes.sensitivity.report_id);
238 	}
239 	return ret;
240 }
241 
242 /* Function to initialize the processing for usage id */
243 static int hid_press_probe(struct platform_device *pdev)
244 {
245 	int ret = 0;
246 	static const char *name = "press";
247 	struct iio_dev *indio_dev;
248 	struct press_state *press_state;
249 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
250 
251 	indio_dev = devm_iio_device_alloc(&pdev->dev,
252 				sizeof(struct press_state));
253 	if (!indio_dev)
254 		return -ENOMEM;
255 	platform_set_drvdata(pdev, indio_dev);
256 
257 	press_state = iio_priv(indio_dev);
258 	press_state->common_attributes.hsdev = hsdev;
259 	press_state->common_attributes.pdev = pdev;
260 
261 	ret = hid_sensor_parse_common_attributes(hsdev,
262 					HID_USAGE_SENSOR_PRESSURE,
263 					&press_state->common_attributes);
264 	if (ret) {
265 		dev_err(&pdev->dev, "failed to setup common attributes\n");
266 		return ret;
267 	}
268 
269 	indio_dev->channels = kmemdup(press_channels, sizeof(press_channels),
270 				      GFP_KERNEL);
271 	if (!indio_dev->channels) {
272 		dev_err(&pdev->dev, "failed to duplicate channels\n");
273 		return -ENOMEM;
274 	}
275 
276 	ret = press_parse_report(pdev, hsdev,
277 				 (struct iio_chan_spec *)indio_dev->channels,
278 				 HID_USAGE_SENSOR_PRESSURE, press_state);
279 	if (ret) {
280 		dev_err(&pdev->dev, "failed to setup attributes\n");
281 		goto error_free_dev_mem;
282 	}
283 
284 	indio_dev->num_channels =
285 				ARRAY_SIZE(press_channels);
286 	indio_dev->dev.parent = &pdev->dev;
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 		goto error_free_dev_mem;
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 error_free_dev_mem:
323 	kfree(indio_dev->channels);
324 	return ret;
325 }
326 
327 /* Function to deinitialize the processing for usage id */
328 static int hid_press_remove(struct platform_device *pdev)
329 {
330 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
331 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
332 	struct press_state *press_state = iio_priv(indio_dev);
333 
334 	sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_PRESSURE);
335 	iio_device_unregister(indio_dev);
336 	hid_sensor_remove_trigger(indio_dev, &press_state->common_attributes);
337 	kfree(indio_dev->channels);
338 
339 	return 0;
340 }
341 
342 static const struct platform_device_id hid_press_ids[] = {
343 	{
344 		/* Format: HID-SENSOR-usage_id_in_hex_lowercase */
345 		.name = "HID-SENSOR-200031",
346 	},
347 	{ /* sentinel */ }
348 };
349 MODULE_DEVICE_TABLE(platform, hid_press_ids);
350 
351 static struct platform_driver hid_press_platform_driver = {
352 	.id_table = hid_press_ids,
353 	.driver = {
354 		.name	= KBUILD_MODNAME,
355 		.pm	= &hid_sensor_pm_ops,
356 	},
357 	.probe		= hid_press_probe,
358 	.remove		= hid_press_remove,
359 };
360 module_platform_driver(hid_press_platform_driver);
361 
362 MODULE_DESCRIPTION("HID Sensor Pressure");
363 MODULE_AUTHOR("Archana Patni <archana.patni@intel.com>");
364 MODULE_LICENSE("GPL");
365