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/platform_device.h>
12
13 #include "hid-sensor-trigger.h"
14
15 struct hid_humidity_state {
16 struct hid_sensor_common common_attributes;
17 struct hid_sensor_hub_attribute_info humidity_attr;
18 s32 humidity_data;
19 int scale_pre_decml;
20 int scale_post_decml;
21 int scale_precision;
22 int value_offset;
23 };
24
25 /* Channel definitions */
26 static const struct iio_chan_spec humidity_channels[] = {
27 {
28 .type = IIO_HUMIDITYRELATIVE,
29 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
30 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
31 BIT(IIO_CHAN_INFO_SCALE) |
32 BIT(IIO_CHAN_INFO_SAMP_FREQ) |
33 BIT(IIO_CHAN_INFO_HYSTERESIS),
34 },
35 IIO_CHAN_SOFT_TIMESTAMP(1)
36 };
37
38 /* Adjust channel real bits based on report descriptor */
humidity_adjust_channel_bit_mask(struct iio_chan_spec * channels,int channel,int size)39 static void humidity_adjust_channel_bit_mask(struct iio_chan_spec *channels,
40 int channel, int size)
41 {
42 channels[channel].scan_type.sign = 's';
43 /* Real storage bits will change based on the report desc. */
44 channels[channel].scan_type.realbits = size * 8;
45 /* Maximum size of a sample to capture is s32 */
46 channels[channel].scan_type.storagebits = sizeof(s32) * 8;
47 }
48
humidity_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)49 static int humidity_read_raw(struct iio_dev *indio_dev,
50 struct iio_chan_spec const *chan,
51 int *val, int *val2, long mask)
52 {
53 struct hid_humidity_state *humid_st = iio_priv(indio_dev);
54
55 switch (mask) {
56 case IIO_CHAN_INFO_RAW:
57 if (chan->type != IIO_HUMIDITYRELATIVE)
58 return -EINVAL;
59 hid_sensor_power_state(&humid_st->common_attributes, true);
60 *val = sensor_hub_input_attr_get_raw_value(
61 humid_st->common_attributes.hsdev,
62 HID_USAGE_SENSOR_HUMIDITY,
63 HID_USAGE_SENSOR_ATMOSPHERIC_HUMIDITY,
64 humid_st->humidity_attr.report_id,
65 SENSOR_HUB_SYNC,
66 humid_st->humidity_attr.logical_minimum < 0);
67 hid_sensor_power_state(&humid_st->common_attributes, false);
68
69 return IIO_VAL_INT;
70
71 case IIO_CHAN_INFO_SCALE:
72 *val = humid_st->scale_pre_decml;
73 *val2 = humid_st->scale_post_decml;
74
75 return humid_st->scale_precision;
76
77 case IIO_CHAN_INFO_OFFSET:
78 *val = humid_st->value_offset;
79
80 return IIO_VAL_INT;
81
82 case IIO_CHAN_INFO_SAMP_FREQ:
83 return hid_sensor_read_samp_freq_value(
84 &humid_st->common_attributes, val, val2);
85
86 case IIO_CHAN_INFO_HYSTERESIS:
87 return hid_sensor_read_raw_hyst_value(
88 &humid_st->common_attributes, val, val2);
89
90 default:
91 return -EINVAL;
92 }
93 }
94
humidity_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)95 static int humidity_write_raw(struct iio_dev *indio_dev,
96 struct iio_chan_spec const *chan,
97 int val, int val2, long mask)
98 {
99 struct hid_humidity_state *humid_st = iio_priv(indio_dev);
100
101 switch (mask) {
102 case IIO_CHAN_INFO_SAMP_FREQ:
103 return hid_sensor_write_samp_freq_value(
104 &humid_st->common_attributes, val, val2);
105
106 case IIO_CHAN_INFO_HYSTERESIS:
107 return hid_sensor_write_raw_hyst_value(
108 &humid_st->common_attributes, val, val2);
109
110 default:
111 return -EINVAL;
112 }
113 }
114
115 static const struct iio_info humidity_info = {
116 .read_raw = &humidity_read_raw,
117 .write_raw = &humidity_write_raw,
118 };
119
120 /* Callback handler to send event after all samples are received and captured */
humidity_proc_event(struct hid_sensor_hub_device * hsdev,unsigned int usage_id,void * pdev)121 static int humidity_proc_event(struct hid_sensor_hub_device *hsdev,
122 unsigned int usage_id, void *pdev)
123 {
124 struct iio_dev *indio_dev = platform_get_drvdata(pdev);
125 struct hid_humidity_state *humid_st = iio_priv(indio_dev);
126
127 if (atomic_read(&humid_st->common_attributes.data_ready))
128 iio_push_to_buffers_with_timestamp(indio_dev,
129 &humid_st->humidity_data,
130 iio_get_time_ns(indio_dev));
131
132 return 0;
133 }
134
135 /* Capture samples in local storage */
humidity_capture_sample(struct hid_sensor_hub_device * hsdev,unsigned int usage_id,size_t raw_len,char * raw_data,void * pdev)136 static int humidity_capture_sample(struct hid_sensor_hub_device *hsdev,
137 unsigned int usage_id, size_t raw_len,
138 char *raw_data, void *pdev)
139 {
140 struct iio_dev *indio_dev = platform_get_drvdata(pdev);
141 struct hid_humidity_state *humid_st = iio_priv(indio_dev);
142
143 switch (usage_id) {
144 case HID_USAGE_SENSOR_ATMOSPHERIC_HUMIDITY:
145 humid_st->humidity_data = *(s32 *)raw_data;
146
147 return 0;
148 default:
149 return -EINVAL;
150 }
151 }
152
153 /* Parse report which is specific to an usage id */
humidity_parse_report(struct platform_device * pdev,struct hid_sensor_hub_device * hsdev,struct iio_chan_spec * channels,unsigned int usage_id,struct hid_humidity_state * st)154 static int humidity_parse_report(struct platform_device *pdev,
155 struct hid_sensor_hub_device *hsdev,
156 struct iio_chan_spec *channels,
157 unsigned int usage_id,
158 struct hid_humidity_state *st)
159 {
160 int ret;
161
162 ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
163 usage_id,
164 HID_USAGE_SENSOR_ATMOSPHERIC_HUMIDITY,
165 &st->humidity_attr);
166 if (ret < 0)
167 return ret;
168
169 humidity_adjust_channel_bit_mask(channels, 0, st->humidity_attr.size);
170
171 st->scale_precision = hid_sensor_format_scale(
172 HID_USAGE_SENSOR_HUMIDITY,
173 &st->humidity_attr,
174 &st->scale_pre_decml,
175 &st->scale_post_decml);
176
177 /* Set Sensitivity field ids, when there is no individual modifier */
178 if (st->common_attributes.sensitivity.index < 0)
179 sensor_hub_input_get_attribute_info(hsdev,
180 HID_FEATURE_REPORT, usage_id,
181 HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS |
182 HID_USAGE_SENSOR_ATMOSPHERIC_HUMIDITY,
183 &st->common_attributes.sensitivity);
184
185 return ret;
186 }
187
188 static struct hid_sensor_hub_callbacks humidity_callbacks = {
189 .send_event = &humidity_proc_event,
190 .capture_sample = &humidity_capture_sample,
191 };
192
193 /* Function to initialize the processing for usage id */
hid_humidity_probe(struct platform_device * pdev)194 static int hid_humidity_probe(struct platform_device *pdev)
195 {
196 static const char *name = "humidity";
197 struct iio_dev *indio_dev;
198 struct hid_humidity_state *humid_st;
199 struct iio_chan_spec *humid_chans;
200 struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);
201 int ret;
202
203 indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*humid_st));
204 if (!indio_dev)
205 return -ENOMEM;
206
207 humid_st = iio_priv(indio_dev);
208 humid_st->common_attributes.hsdev = hsdev;
209 humid_st->common_attributes.pdev = pdev;
210
211 ret = hid_sensor_parse_common_attributes(hsdev,
212 HID_USAGE_SENSOR_HUMIDITY,
213 &humid_st->common_attributes);
214 if (ret)
215 return ret;
216
217 humid_chans = devm_kmemdup(&indio_dev->dev, humidity_channels,
218 sizeof(humidity_channels), GFP_KERNEL);
219 if (!humid_chans)
220 return -ENOMEM;
221
222 ret = humidity_parse_report(pdev, hsdev, humid_chans,
223 HID_USAGE_SENSOR_HUMIDITY, humid_st);
224 if (ret)
225 return ret;
226
227 indio_dev->channels = humid_chans;
228 indio_dev->num_channels = ARRAY_SIZE(humidity_channels);
229 indio_dev->info = &humidity_info;
230 indio_dev->name = name;
231 indio_dev->modes = INDIO_DIRECT_MODE;
232
233 atomic_set(&humid_st->common_attributes.data_ready, 0);
234
235 ret = hid_sensor_setup_trigger(indio_dev, name,
236 &humid_st->common_attributes);
237 if (ret)
238 return ret;
239
240 platform_set_drvdata(pdev, indio_dev);
241
242 humidity_callbacks.pdev = pdev;
243 ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_HUMIDITY,
244 &humidity_callbacks);
245 if (ret)
246 goto error_remove_trigger;
247
248 ret = iio_device_register(indio_dev);
249 if (ret)
250 goto error_remove_callback;
251
252 return ret;
253
254 error_remove_callback:
255 sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_HUMIDITY);
256 error_remove_trigger:
257 hid_sensor_remove_trigger(indio_dev, &humid_st->common_attributes);
258 return ret;
259 }
260
261 /* Function to deinitialize the processing for usage id */
hid_humidity_remove(struct platform_device * pdev)262 static int hid_humidity_remove(struct platform_device *pdev)
263 {
264 struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);
265 struct iio_dev *indio_dev = platform_get_drvdata(pdev);
266 struct hid_humidity_state *humid_st = iio_priv(indio_dev);
267
268 iio_device_unregister(indio_dev);
269 sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_HUMIDITY);
270 hid_sensor_remove_trigger(indio_dev, &humid_st->common_attributes);
271
272 return 0;
273 }
274
275 static const struct platform_device_id hid_humidity_ids[] = {
276 {
277 /* Format: HID-SENSOR-usage_id_in_hex_lowercase */
278 .name = "HID-SENSOR-200032",
279 },
280 { /* sentinel */ }
281 };
282 MODULE_DEVICE_TABLE(platform, hid_humidity_ids);
283
284 static struct platform_driver hid_humidity_platform_driver = {
285 .id_table = hid_humidity_ids,
286 .driver = {
287 .name = KBUILD_MODNAME,
288 .pm = &hid_sensor_pm_ops,
289 },
290 .probe = hid_humidity_probe,
291 .remove = hid_humidity_remove,
292 };
293 module_platform_driver(hid_humidity_platform_driver);
294
295 MODULE_DESCRIPTION("HID Environmental humidity sensor");
296 MODULE_AUTHOR("Song Hongyan <hongyan.song@intel.com>");
297 MODULE_LICENSE("GPL v2");
298