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 u64 timestamp __aligned(8); 21 } scan; 22 int scale_pre_decml; 23 int scale_post_decml; 24 int scale_precision; 25 int value_offset; 26 }; 27 28 /* Channel definitions */ 29 static const struct iio_chan_spec humidity_channels[] = { 30 { 31 .type = IIO_HUMIDITYRELATIVE, 32 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), 33 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) | 34 BIT(IIO_CHAN_INFO_SCALE) | 35 BIT(IIO_CHAN_INFO_SAMP_FREQ) | 36 BIT(IIO_CHAN_INFO_HYSTERESIS), 37 }, 38 IIO_CHAN_SOFT_TIMESTAMP(1) 39 }; 40 41 /* Adjust channel real bits based on report descriptor */ 42 static void humidity_adjust_channel_bit_mask(struct iio_chan_spec *channels, 43 int channel, int size) 44 { 45 channels[channel].scan_type.sign = 's'; 46 /* Real storage bits will change based on the report desc. */ 47 channels[channel].scan_type.realbits = size * 8; 48 /* Maximum size of a sample to capture is s32 */ 49 channels[channel].scan_type.storagebits = sizeof(s32) * 8; 50 } 51 52 static int humidity_read_raw(struct iio_dev *indio_dev, 53 struct iio_chan_spec const *chan, 54 int *val, int *val2, long mask) 55 { 56 struct hid_humidity_state *humid_st = iio_priv(indio_dev); 57 58 switch (mask) { 59 case IIO_CHAN_INFO_RAW: 60 if (chan->type != IIO_HUMIDITYRELATIVE) 61 return -EINVAL; 62 hid_sensor_power_state(&humid_st->common_attributes, true); 63 *val = sensor_hub_input_attr_get_raw_value( 64 humid_st->common_attributes.hsdev, 65 HID_USAGE_SENSOR_HUMIDITY, 66 HID_USAGE_SENSOR_ATMOSPHERIC_HUMIDITY, 67 humid_st->humidity_attr.report_id, 68 SENSOR_HUB_SYNC, 69 humid_st->humidity_attr.logical_minimum < 0); 70 hid_sensor_power_state(&humid_st->common_attributes, false); 71 72 return IIO_VAL_INT; 73 74 case IIO_CHAN_INFO_SCALE: 75 *val = humid_st->scale_pre_decml; 76 *val2 = humid_st->scale_post_decml; 77 78 return humid_st->scale_precision; 79 80 case IIO_CHAN_INFO_OFFSET: 81 *val = humid_st->value_offset; 82 83 return IIO_VAL_INT; 84 85 case IIO_CHAN_INFO_SAMP_FREQ: 86 return hid_sensor_read_samp_freq_value( 87 &humid_st->common_attributes, val, val2); 88 89 case IIO_CHAN_INFO_HYSTERESIS: 90 return hid_sensor_read_raw_hyst_value( 91 &humid_st->common_attributes, val, val2); 92 93 default: 94 return -EINVAL; 95 } 96 } 97 98 static int humidity_write_raw(struct iio_dev *indio_dev, 99 struct iio_chan_spec const *chan, 100 int val, int val2, long mask) 101 { 102 struct hid_humidity_state *humid_st = iio_priv(indio_dev); 103 104 switch (mask) { 105 case IIO_CHAN_INFO_SAMP_FREQ: 106 return hid_sensor_write_samp_freq_value( 107 &humid_st->common_attributes, val, val2); 108 109 case IIO_CHAN_INFO_HYSTERESIS: 110 return hid_sensor_write_raw_hyst_value( 111 &humid_st->common_attributes, val, val2); 112 113 default: 114 return -EINVAL; 115 } 116 } 117 118 static const struct iio_info humidity_info = { 119 .read_raw = &humidity_read_raw, 120 .write_raw = &humidity_write_raw, 121 }; 122 123 /* Callback handler to send event after all samples are received and captured */ 124 static int humidity_proc_event(struct hid_sensor_hub_device *hsdev, 125 unsigned int usage_id, void *pdev) 126 { 127 struct iio_dev *indio_dev = platform_get_drvdata(pdev); 128 struct hid_humidity_state *humid_st = iio_priv(indio_dev); 129 130 if (atomic_read(&humid_st->common_attributes.data_ready)) 131 iio_push_to_buffers_with_timestamp(indio_dev, &humid_st->scan, 132 iio_get_time_ns(indio_dev)); 133 134 return 0; 135 } 136 137 /* Capture samples in local storage */ 138 static int humidity_capture_sample(struct hid_sensor_hub_device *hsdev, 139 unsigned int usage_id, size_t raw_len, 140 char *raw_data, void *pdev) 141 { 142 struct iio_dev *indio_dev = platform_get_drvdata(pdev); 143 struct hid_humidity_state *humid_st = iio_priv(indio_dev); 144 145 switch (usage_id) { 146 case HID_USAGE_SENSOR_ATMOSPHERIC_HUMIDITY: 147 humid_st->scan.humidity_data = *(s32 *)raw_data; 148 149 return 0; 150 default: 151 return -EINVAL; 152 } 153 } 154 155 /* Parse report which is specific to an usage id */ 156 static int humidity_parse_report(struct platform_device *pdev, 157 struct hid_sensor_hub_device *hsdev, 158 struct iio_chan_spec *channels, 159 unsigned int usage_id, 160 struct hid_humidity_state *st) 161 { 162 int ret; 163 164 ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT, 165 usage_id, 166 HID_USAGE_SENSOR_ATMOSPHERIC_HUMIDITY, 167 &st->humidity_attr); 168 if (ret < 0) 169 return ret; 170 171 humidity_adjust_channel_bit_mask(channels, 0, st->humidity_attr.size); 172 173 st->scale_precision = hid_sensor_format_scale( 174 HID_USAGE_SENSOR_HUMIDITY, 175 &st->humidity_attr, 176 &st->scale_pre_decml, 177 &st->scale_post_decml); 178 179 /* Set Sensitivity field ids, when there is no individual modifier */ 180 if (st->common_attributes.sensitivity.index < 0) 181 sensor_hub_input_get_attribute_info(hsdev, 182 HID_FEATURE_REPORT, usage_id, 183 HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS | 184 HID_USAGE_SENSOR_ATMOSPHERIC_HUMIDITY, 185 &st->common_attributes.sensitivity); 186 187 return ret; 188 } 189 190 static struct hid_sensor_hub_callbacks humidity_callbacks = { 191 .send_event = &humidity_proc_event, 192 .capture_sample = &humidity_capture_sample, 193 }; 194 195 /* Function to initialize the processing for usage id */ 196 static int hid_humidity_probe(struct platform_device *pdev) 197 { 198 static const char *name = "humidity"; 199 struct iio_dev *indio_dev; 200 struct hid_humidity_state *humid_st; 201 struct iio_chan_spec *humid_chans; 202 struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev); 203 int ret; 204 205 indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*humid_st)); 206 if (!indio_dev) 207 return -ENOMEM; 208 209 humid_st = iio_priv(indio_dev); 210 humid_st->common_attributes.hsdev = hsdev; 211 humid_st->common_attributes.pdev = pdev; 212 213 ret = hid_sensor_parse_common_attributes(hsdev, 214 HID_USAGE_SENSOR_HUMIDITY, 215 &humid_st->common_attributes); 216 if (ret) 217 return ret; 218 219 humid_chans = devm_kmemdup(&indio_dev->dev, humidity_channels, 220 sizeof(humidity_channels), GFP_KERNEL); 221 if (!humid_chans) 222 return -ENOMEM; 223 224 ret = humidity_parse_report(pdev, hsdev, humid_chans, 225 HID_USAGE_SENSOR_HUMIDITY, humid_st); 226 if (ret) 227 return ret; 228 229 indio_dev->channels = humid_chans; 230 indio_dev->num_channels = ARRAY_SIZE(humidity_channels); 231 indio_dev->info = &humidity_info; 232 indio_dev->name = name; 233 indio_dev->modes = INDIO_DIRECT_MODE; 234 235 atomic_set(&humid_st->common_attributes.data_ready, 0); 236 237 ret = hid_sensor_setup_trigger(indio_dev, name, 238 &humid_st->common_attributes); 239 if (ret) 240 return ret; 241 242 platform_set_drvdata(pdev, indio_dev); 243 244 humidity_callbacks.pdev = pdev; 245 ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_HUMIDITY, 246 &humidity_callbacks); 247 if (ret) 248 goto error_remove_trigger; 249 250 ret = iio_device_register(indio_dev); 251 if (ret) 252 goto error_remove_callback; 253 254 return ret; 255 256 error_remove_callback: 257 sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_HUMIDITY); 258 error_remove_trigger: 259 hid_sensor_remove_trigger(indio_dev, &humid_st->common_attributes); 260 return ret; 261 } 262 263 /* Function to deinitialize the processing for usage id */ 264 static int hid_humidity_remove(struct platform_device *pdev) 265 { 266 struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev); 267 struct iio_dev *indio_dev = platform_get_drvdata(pdev); 268 struct hid_humidity_state *humid_st = iio_priv(indio_dev); 269 270 iio_device_unregister(indio_dev); 271 sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_HUMIDITY); 272 hid_sensor_remove_trigger(indio_dev, &humid_st->common_attributes); 273 274 return 0; 275 } 276 277 static const struct platform_device_id hid_humidity_ids[] = { 278 { 279 /* Format: HID-SENSOR-usage_id_in_hex_lowercase */ 280 .name = "HID-SENSOR-200032", 281 }, 282 { /* sentinel */ } 283 }; 284 MODULE_DEVICE_TABLE(platform, hid_humidity_ids); 285 286 static struct platform_driver hid_humidity_platform_driver = { 287 .id_table = hid_humidity_ids, 288 .driver = { 289 .name = KBUILD_MODNAME, 290 .pm = &hid_sensor_pm_ops, 291 }, 292 .probe = hid_humidity_probe, 293 .remove = hid_humidity_remove, 294 }; 295 module_platform_driver(hid_humidity_platform_driver); 296 297 MODULE_DESCRIPTION("HID Environmental humidity sensor"); 298 MODULE_AUTHOR("Song Hongyan <hongyan.song@intel.com>"); 299 MODULE_LICENSE("GPL v2"); 300