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 struct { 19 s32 humidity_data; 20 aligned_s64 timestamp; 21 } scan; 22 int scale_pre_decml; 23 int scale_post_decml; 24 int scale_precision; 25 int value_offset; 26 }; 27 28 static const u32 humidity_sensitivity_addresses[] = { 29 HID_USAGE_SENSOR_ATMOSPHERIC_HUMIDITY, 30 }; 31 32 /* Channel definitions */ 33 static const struct iio_chan_spec humidity_channels[] = { 34 { 35 .type = IIO_HUMIDITYRELATIVE, 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 }, 42 IIO_CHAN_SOFT_TIMESTAMP(1) 43 }; 44 45 /* Adjust channel real bits based on report descriptor */ 46 static void humidity_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 s32 */ 53 channels[channel].scan_type.storagebits = sizeof(s32) * 8; 54 } 55 56 static int humidity_read_raw(struct iio_dev *indio_dev, 57 struct iio_chan_spec const *chan, 58 int *val, int *val2, long mask) 59 { 60 struct hid_humidity_state *humid_st = iio_priv(indio_dev); 61 62 switch (mask) { 63 case IIO_CHAN_INFO_RAW: 64 if (chan->type != IIO_HUMIDITYRELATIVE) 65 return -EINVAL; 66 hid_sensor_power_state(&humid_st->common_attributes, true); 67 *val = sensor_hub_input_attr_get_raw_value( 68 humid_st->common_attributes.hsdev, 69 HID_USAGE_SENSOR_HUMIDITY, 70 HID_USAGE_SENSOR_ATMOSPHERIC_HUMIDITY, 71 humid_st->humidity_attr.report_id, 72 SENSOR_HUB_SYNC, 73 humid_st->humidity_attr.logical_minimum < 0); 74 hid_sensor_power_state(&humid_st->common_attributes, false); 75 76 return IIO_VAL_INT; 77 78 case IIO_CHAN_INFO_SCALE: 79 *val = humid_st->scale_pre_decml; 80 *val2 = humid_st->scale_post_decml; 81 82 return humid_st->scale_precision; 83 84 case IIO_CHAN_INFO_OFFSET: 85 *val = humid_st->value_offset; 86 87 return IIO_VAL_INT; 88 89 case IIO_CHAN_INFO_SAMP_FREQ: 90 return hid_sensor_read_samp_freq_value( 91 &humid_st->common_attributes, val, val2); 92 93 case IIO_CHAN_INFO_HYSTERESIS: 94 return hid_sensor_read_raw_hyst_value( 95 &humid_st->common_attributes, val, val2); 96 97 default: 98 return -EINVAL; 99 } 100 } 101 102 static int humidity_write_raw(struct iio_dev *indio_dev, 103 struct iio_chan_spec const *chan, 104 int val, int val2, long mask) 105 { 106 struct hid_humidity_state *humid_st = iio_priv(indio_dev); 107 108 switch (mask) { 109 case IIO_CHAN_INFO_SAMP_FREQ: 110 return hid_sensor_write_samp_freq_value( 111 &humid_st->common_attributes, val, val2); 112 113 case IIO_CHAN_INFO_HYSTERESIS: 114 return hid_sensor_write_raw_hyst_value( 115 &humid_st->common_attributes, val, val2); 116 117 default: 118 return -EINVAL; 119 } 120 } 121 122 static const struct iio_info humidity_info = { 123 .read_raw = &humidity_read_raw, 124 .write_raw = &humidity_write_raw, 125 }; 126 127 /* Callback handler to send event after all samples are received and captured */ 128 static int humidity_proc_event(struct hid_sensor_hub_device *hsdev, 129 u32 usage_id, void *pdev) 130 { 131 struct iio_dev *indio_dev = platform_get_drvdata(pdev); 132 struct hid_humidity_state *humid_st = iio_priv(indio_dev); 133 134 if (atomic_read(&humid_st->common_attributes.data_ready)) 135 iio_push_to_buffers_with_timestamp(indio_dev, &humid_st->scan, 136 iio_get_time_ns(indio_dev)); 137 138 return 0; 139 } 140 141 /* Capture samples in local storage */ 142 static int humidity_capture_sample(struct hid_sensor_hub_device *hsdev, 143 u32 usage_id, 144 size_t raw_len, char *raw_data, 145 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 */ 161 static int humidity_parse_report(struct platform_device *pdev, 162 struct hid_sensor_hub_device *hsdev, 163 struct iio_chan_spec *channels, 164 u32 usage_id, 165 struct hid_humidity_state *st) 166 { 167 int ret; 168 169 ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT, 170 usage_id, 171 HID_USAGE_SENSOR_ATMOSPHERIC_HUMIDITY, 172 &st->humidity_attr); 173 if (ret < 0) 174 return ret; 175 176 humidity_adjust_channel_bit_mask(channels, 0, st->humidity_attr.size); 177 178 st->scale_precision = hid_sensor_format_scale( 179 HID_USAGE_SENSOR_HUMIDITY, 180 &st->humidity_attr, 181 &st->scale_pre_decml, 182 &st->scale_post_decml); 183 184 return ret; 185 } 186 187 static 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 */ 193 static 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(&pdev->dev); 200 int ret; 201 202 indio_dev = devm_iio_device_alloc(&pdev->dev, 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 &humid_st->common_attributes, 213 humidity_sensitivity_addresses, 214 ARRAY_SIZE(humidity_sensitivity_addresses)); 215 if (ret) 216 return ret; 217 218 humid_chans = devm_kmemdup(&pdev->dev, humidity_channels, 219 sizeof(humidity_channels), GFP_KERNEL); 220 if (!humid_chans) 221 return -ENOMEM; 222 223 ret = humidity_parse_report(pdev, hsdev, humid_chans, 224 HID_USAGE_SENSOR_HUMIDITY, 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(&humid_st->common_attributes.data_ready, 0); 235 236 ret = hid_sensor_setup_trigger(indio_dev, name, 237 &humid_st->common_attributes); 238 if (ret) 239 return ret; 240 241 platform_set_drvdata(pdev, indio_dev); 242 243 humidity_callbacks.pdev = pdev; 244 ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_HUMIDITY, 245 &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; 254 255 error_remove_callback: 256 sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_HUMIDITY); 257 error_remove_trigger: 258 hid_sensor_remove_trigger(indio_dev, &humid_st->common_attributes); 259 return ret; 260 } 261 262 /* Function to deinitialize the processing for usage id */ 263 static void hid_humidity_remove(struct platform_device *pdev) 264 { 265 struct hid_sensor_hub_device *hsdev = dev_get_platdata(&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, &humid_st->common_attributes); 272 } 273 274 static 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 { } 280 }; 281 MODULE_DEVICE_TABLE(platform, hid_humidity_ids); 282 283 static 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 = hid_humidity_remove, 291 }; 292 module_platform_driver(hid_humidity_platform_driver); 293 294 MODULE_DESCRIPTION("HID Environmental humidity sensor"); 295 MODULE_AUTHOR("Song Hongyan <hongyan.song@intel.com>"); 296 MODULE_LICENSE("GPL v2"); 297 MODULE_IMPORT_NS("IIO_HID"); 298