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 */ 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 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 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 */ 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 */ 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 */ 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 */ 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 */ 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