1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * HID Sensors Driver
4 * Copyright (c) 2017, Intel Corporation.
5 */
6#include <linux/device.h>
7#include <linux/hid-sensor-hub.h>
8#include <linux/iio/buffer.h>
9#include <linux/iio/iio.h>
10#include <linux/module.h>
11#include <linux/mod_devicetable.h>
12#include <linux/platform_device.h>
13
14#include "hid-sensor-trigger.h"
15
16struct hid_humidity_state {
17 struct hid_sensor_common common_attributes;
18 struct hid_sensor_hub_attribute_info humidity_attr;
19 struct {
20 s32 humidity_data;
21 u64 timestamp __aligned(8);
22 } scan;
23 int scale_pre_decml;
24 int scale_post_decml;
25 int scale_precision;
26 int value_offset;
27};
28
29static const u32 humidity_sensitivity_addresses[] = {
30 HID_USAGE_SENSOR_ATMOSPHERIC_HUMIDITY,
31};
32
33/* Channel definitions */
34static const struct iio_chan_spec humidity_channels[] = {
35 {
36 .type = IIO_HUMIDITYRELATIVE,
37 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
38 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
39 BIT(IIO_CHAN_INFO_SCALE) |
40 BIT(IIO_CHAN_INFO_SAMP_FREQ) |
41 BIT(IIO_CHAN_INFO_HYSTERESIS),
42 },
43 IIO_CHAN_SOFT_TIMESTAMP(1)
44};
45
46/* Adjust channel real bits based on report descriptor */
47static void humidity_adjust_channel_bit_mask(struct iio_chan_spec *channels,
48 int channel, int size)
49{
50 channels[channel].scan_type.sign = 's';
51 /* Real storage bits will change based on the report desc. */
52 channels[channel].scan_type.realbits = size * 8;
53 /* Maximum size of a sample to capture is s32 */
54 channels[channel].scan_type.storagebits = sizeof(s32) * 8;
55}
56
57static int humidity_read_raw(struct iio_dev *indio_dev,
58 struct iio_chan_spec const *chan,
59 int *val, int *val2, long mask)
60{
61 struct hid_humidity_state *humid_st = iio_priv(indio_dev);
62
63 switch (mask) {
64 case IIO_CHAN_INFO_RAW:
65 if (chan->type != IIO_HUMIDITYRELATIVE)
66 return -EINVAL;
67 hid_sensor_power_state(st: &humid_st->common_attributes, state: true);
68 *val = sensor_hub_input_attr_get_raw_value(
69 hsdev: humid_st->common_attributes.hsdev,
70 HID_USAGE_SENSOR_HUMIDITY,
71 HID_USAGE_SENSOR_ATMOSPHERIC_HUMIDITY,
72 report_id: humid_st->humidity_attr.report_id,
73 flag: SENSOR_HUB_SYNC,
74 is_signed: humid_st->humidity_attr.logical_minimum < 0);
75 hid_sensor_power_state(st: &humid_st->common_attributes, state: false);
76
77 return IIO_VAL_INT;
78
79 case IIO_CHAN_INFO_SCALE:
80 *val = humid_st->scale_pre_decml;
81 *val2 = humid_st->scale_post_decml;
82
83 return humid_st->scale_precision;
84
85 case IIO_CHAN_INFO_OFFSET:
86 *val = humid_st->value_offset;
87
88 return IIO_VAL_INT;
89
90 case IIO_CHAN_INFO_SAMP_FREQ:
91 return hid_sensor_read_samp_freq_value(
92 st: &humid_st->common_attributes, val1: val, val2);
93
94 case IIO_CHAN_INFO_HYSTERESIS:
95 return hid_sensor_read_raw_hyst_value(
96 st: &humid_st->common_attributes, val1: val, val2);
97
98 default:
99 return -EINVAL;
100 }
101}
102
103static int humidity_write_raw(struct iio_dev *indio_dev,
104 struct iio_chan_spec const *chan,
105 int val, int val2, long mask)
106{
107 struct hid_humidity_state *humid_st = iio_priv(indio_dev);
108
109 switch (mask) {
110 case IIO_CHAN_INFO_SAMP_FREQ:
111 return hid_sensor_write_samp_freq_value(
112 st: &humid_st->common_attributes, val1: val, val2);
113
114 case IIO_CHAN_INFO_HYSTERESIS:
115 return hid_sensor_write_raw_hyst_value(
116 st: &humid_st->common_attributes, val1: val, val2);
117
118 default:
119 return -EINVAL;
120 }
121}
122
123static const struct iio_info humidity_info = {
124 .read_raw = &humidity_read_raw,
125 .write_raw = &humidity_write_raw,
126};
127
128/* Callback handler to send event after all samples are received and captured */
129static int humidity_proc_event(struct hid_sensor_hub_device *hsdev,
130 unsigned int usage_id, void *pdev)
131{
132 struct iio_dev *indio_dev = platform_get_drvdata(pdev);
133 struct hid_humidity_state *humid_st = iio_priv(indio_dev);
134
135 if (atomic_read(v: &humid_st->common_attributes.data_ready))
136 iio_push_to_buffers_with_timestamp(indio_dev, data: &humid_st->scan,
137 timestamp: iio_get_time_ns(indio_dev));
138
139 return 0;
140}
141
142/* Capture samples in local storage */
143static int humidity_capture_sample(struct hid_sensor_hub_device *hsdev,
144 unsigned int usage_id, size_t raw_len,
145 char *raw_data, void *pdev)
146{
147 struct iio_dev *indio_dev = platform_get_drvdata(pdev);
148 struct hid_humidity_state *humid_st = iio_priv(indio_dev);
149
150 switch (usage_id) {
151 case HID_USAGE_SENSOR_ATMOSPHERIC_HUMIDITY:
152 humid_st->scan.humidity_data = *(s32 *)raw_data;
153
154 return 0;
155 default:
156 return -EINVAL;
157 }
158}
159
160/* Parse report which is specific to an usage id */
161static int humidity_parse_report(struct platform_device *pdev,
162 struct hid_sensor_hub_device *hsdev,
163 struct iio_chan_spec *channels,
164 unsigned int usage_id,
165 struct hid_humidity_state *st)
166{
167 int ret;
168
169 ret = sensor_hub_input_get_attribute_info(hsdev, type: HID_INPUT_REPORT,
170 usage_id,
171 HID_USAGE_SENSOR_ATMOSPHERIC_HUMIDITY,
172 info: &st->humidity_attr);
173 if (ret < 0)
174 return ret;
175
176 humidity_adjust_channel_bit_mask(channels, channel: 0, size: st->humidity_attr.size);
177
178 st->scale_precision = hid_sensor_format_scale(
179 HID_USAGE_SENSOR_HUMIDITY,
180 attr_info: &st->humidity_attr,
181 val0: &st->scale_pre_decml,
182 val1: &st->scale_post_decml);
183
184 return ret;
185}
186
187static struct hid_sensor_hub_callbacks humidity_callbacks = {
188 .send_event = &humidity_proc_event,
189 .capture_sample = &humidity_capture_sample,
190};
191
192/* Function to initialize the processing for usage id */
193static int hid_humidity_probe(struct platform_device *pdev)
194{
195 static const char *name = "humidity";
196 struct iio_dev *indio_dev;
197 struct hid_humidity_state *humid_st;
198 struct iio_chan_spec *humid_chans;
199 struct hid_sensor_hub_device *hsdev = dev_get_platdata(dev: &pdev->dev);
200 int ret;
201
202 indio_dev = devm_iio_device_alloc(parent: &pdev->dev, sizeof_priv: sizeof(*humid_st));
203 if (!indio_dev)
204 return -ENOMEM;
205
206 humid_st = iio_priv(indio_dev);
207 humid_st->common_attributes.hsdev = hsdev;
208 humid_st->common_attributes.pdev = pdev;
209
210 ret = hid_sensor_parse_common_attributes(hsdev,
211 HID_USAGE_SENSOR_HUMIDITY,
212 st: &humid_st->common_attributes,
213 sensitivity_addresses: humidity_sensitivity_addresses,
214 ARRAY_SIZE(humidity_sensitivity_addresses));
215 if (ret)
216 return ret;
217
218 humid_chans = devm_kmemdup(dev: &indio_dev->dev, src: humidity_channels,
219 len: sizeof(humidity_channels), GFP_KERNEL);
220 if (!humid_chans)
221 return -ENOMEM;
222
223 ret = humidity_parse_report(pdev, hsdev, channels: humid_chans,
224 HID_USAGE_SENSOR_HUMIDITY, st: humid_st);
225 if (ret)
226 return ret;
227
228 indio_dev->channels = humid_chans;
229 indio_dev->num_channels = ARRAY_SIZE(humidity_channels);
230 indio_dev->info = &humidity_info;
231 indio_dev->name = name;
232 indio_dev->modes = INDIO_DIRECT_MODE;
233
234 atomic_set(v: &humid_st->common_attributes.data_ready, i: 0);
235
236 ret = hid_sensor_setup_trigger(indio_dev, name,
237 attrb: &humid_st->common_attributes);
238 if (ret)
239 return ret;
240
241 platform_set_drvdata(pdev, data: indio_dev);
242
243 humidity_callbacks.pdev = pdev;
244 ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_HUMIDITY,
245 usage_callback: &humidity_callbacks);
246 if (ret)
247 goto error_remove_trigger;
248
249 ret = iio_device_register(indio_dev);
250 if (ret)
251 goto error_remove_callback;
252
253 return ret;
254
255error_remove_callback:
256 sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_HUMIDITY);
257error_remove_trigger:
258 hid_sensor_remove_trigger(indio_dev, attrb: &humid_st->common_attributes);
259 return ret;
260}
261
262/* Function to deinitialize the processing for usage id */
263static void hid_humidity_remove(struct platform_device *pdev)
264{
265 struct hid_sensor_hub_device *hsdev = dev_get_platdata(dev: &pdev->dev);
266 struct iio_dev *indio_dev = platform_get_drvdata(pdev);
267 struct hid_humidity_state *humid_st = iio_priv(indio_dev);
268
269 iio_device_unregister(indio_dev);
270 sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_HUMIDITY);
271 hid_sensor_remove_trigger(indio_dev, attrb: &humid_st->common_attributes);
272}
273
274static const struct platform_device_id hid_humidity_ids[] = {
275 {
276 /* Format: HID-SENSOR-usage_id_in_hex_lowercase */
277 .name = "HID-SENSOR-200032",
278 },
279 { /* sentinel */ }
280};
281MODULE_DEVICE_TABLE(platform, hid_humidity_ids);
282
283static struct platform_driver hid_humidity_platform_driver = {
284 .id_table = hid_humidity_ids,
285 .driver = {
286 .name = KBUILD_MODNAME,
287 .pm = &hid_sensor_pm_ops,
288 },
289 .probe = hid_humidity_probe,
290 .remove_new = hid_humidity_remove,
291};
292module_platform_driver(hid_humidity_platform_driver);
293
294MODULE_DESCRIPTION("HID Environmental humidity sensor");
295MODULE_AUTHOR("Song Hongyan <hongyan.song@intel.com>");
296MODULE_LICENSE("GPL v2");
297MODULE_IMPORT_NS(IIO_HID);
298

source code of linux/drivers/iio/humidity/hid-sensor-humidity.c