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/iio/triggered_buffer.h> 11 #include <linux/iio/trigger_consumer.h> 12 #include <linux/module.h> 13 #include <linux/platform_device.h> 14 15 #include "hid-sensor-trigger.h" 16 17 struct hid_humidity_state { 18 struct hid_sensor_common common_attributes; 19 struct hid_sensor_hub_attribute_info humidity_attr; 20 s32 humidity_data; 21 int scale_pre_decml; 22 int scale_post_decml; 23 int scale_precision; 24 int value_offset; 25 }; 26 27 /* Channel definitions */ 28 static const struct iio_chan_spec humidity_channels[] = { 29 { 30 .type = IIO_HUMIDITYRELATIVE, 31 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), 32 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) | 33 BIT(IIO_CHAN_INFO_SCALE) | 34 BIT(IIO_CHAN_INFO_SAMP_FREQ) | 35 BIT(IIO_CHAN_INFO_HYSTERESIS), 36 }, 37 IIO_CHAN_SOFT_TIMESTAMP(1) 38 }; 39 40 /* Adjust channel real bits based on report descriptor */ 41 static void humidity_adjust_channel_bit_mask(struct iio_chan_spec *channels, 42 int channel, int size) 43 { 44 channels[channel].scan_type.sign = 's'; 45 /* Real storage bits will change based on the report desc. */ 46 channels[channel].scan_type.realbits = size * 8; 47 /* Maximum size of a sample to capture is s32 */ 48 channels[channel].scan_type.storagebits = sizeof(s32) * 8; 49 } 50 51 static int humidity_read_raw(struct iio_dev *indio_dev, 52 struct iio_chan_spec const *chan, 53 int *val, int *val2, long mask) 54 { 55 struct hid_humidity_state *humid_st = iio_priv(indio_dev); 56 57 switch (mask) { 58 case IIO_CHAN_INFO_RAW: 59 if (chan->type != IIO_HUMIDITYRELATIVE) 60 return -EINVAL; 61 hid_sensor_power_state(&humid_st->common_attributes, true); 62 *val = sensor_hub_input_attr_get_raw_value( 63 humid_st->common_attributes.hsdev, 64 HID_USAGE_SENSOR_HUMIDITY, 65 HID_USAGE_SENSOR_ATMOSPHERIC_HUMIDITY, 66 humid_st->humidity_attr.report_id, 67 SENSOR_HUB_SYNC, 68 humid_st->humidity_attr.logical_minimum < 0); 69 hid_sensor_power_state(&humid_st->common_attributes, false); 70 71 return IIO_VAL_INT; 72 73 case IIO_CHAN_INFO_SCALE: 74 *val = humid_st->scale_pre_decml; 75 *val2 = humid_st->scale_post_decml; 76 77 return humid_st->scale_precision; 78 79 case IIO_CHAN_INFO_OFFSET: 80 *val = humid_st->value_offset; 81 82 return IIO_VAL_INT; 83 84 case IIO_CHAN_INFO_SAMP_FREQ: 85 return hid_sensor_read_samp_freq_value( 86 &humid_st->common_attributes, val, val2); 87 88 case IIO_CHAN_INFO_HYSTERESIS: 89 return hid_sensor_read_raw_hyst_value( 90 &humid_st->common_attributes, val, val2); 91 92 default: 93 return -EINVAL; 94 } 95 } 96 97 static int humidity_write_raw(struct iio_dev *indio_dev, 98 struct iio_chan_spec const *chan, 99 int val, int val2, long mask) 100 { 101 struct hid_humidity_state *humid_st = iio_priv(indio_dev); 102 103 switch (mask) { 104 case IIO_CHAN_INFO_SAMP_FREQ: 105 return hid_sensor_write_samp_freq_value( 106 &humid_st->common_attributes, val, val2); 107 108 case IIO_CHAN_INFO_HYSTERESIS: 109 return hid_sensor_write_raw_hyst_value( 110 &humid_st->common_attributes, val, val2); 111 112 default: 113 return -EINVAL; 114 } 115 } 116 117 static const struct iio_info humidity_info = { 118 .read_raw = &humidity_read_raw, 119 .write_raw = &humidity_write_raw, 120 }; 121 122 /* Callback handler to send event after all samples are received and captured */ 123 static int humidity_proc_event(struct hid_sensor_hub_device *hsdev, 124 unsigned int usage_id, void *pdev) 125 { 126 struct iio_dev *indio_dev = platform_get_drvdata(pdev); 127 struct hid_humidity_state *humid_st = iio_priv(indio_dev); 128 129 if (atomic_read(&humid_st->common_attributes.data_ready)) 130 iio_push_to_buffers_with_timestamp(indio_dev, 131 &humid_st->humidity_data, 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->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->dev.parent = &pdev->dev; 232 indio_dev->info = &humidity_info; 233 indio_dev->name = name; 234 indio_dev->modes = INDIO_DIRECT_MODE; 235 236 ret = devm_iio_triggered_buffer_setup(&pdev->dev, indio_dev, 237 &iio_pollfunc_store_time, NULL, NULL); 238 if (ret) 239 return ret; 240 241 atomic_set(&humid_st->common_attributes.data_ready, 0); 242 ret = hid_sensor_setup_trigger(indio_dev, name, 243 &humid_st->common_attributes); 244 if (ret) 245 return ret; 246 247 platform_set_drvdata(pdev, indio_dev); 248 249 humidity_callbacks.pdev = pdev; 250 ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_HUMIDITY, 251 &humidity_callbacks); 252 if (ret) 253 goto error_remove_trigger; 254 255 ret = iio_device_register(indio_dev); 256 if (ret) 257 goto error_remove_callback; 258 259 return ret; 260 261 error_remove_callback: 262 sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_HUMIDITY); 263 error_remove_trigger: 264 hid_sensor_remove_trigger(&humid_st->common_attributes); 265 return ret; 266 } 267 268 /* Function to deinitialize the processing for usage id */ 269 static int hid_humidity_remove(struct platform_device *pdev) 270 { 271 struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev); 272 struct iio_dev *indio_dev = platform_get_drvdata(pdev); 273 struct hid_humidity_state *humid_st = iio_priv(indio_dev); 274 275 iio_device_unregister(indio_dev); 276 sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_HUMIDITY); 277 hid_sensor_remove_trigger(&humid_st->common_attributes); 278 279 return 0; 280 } 281 282 static const struct platform_device_id hid_humidity_ids[] = { 283 { 284 /* Format: HID-SENSOR-usage_id_in_hex_lowercase */ 285 .name = "HID-SENSOR-200032", 286 }, 287 { /* sentinel */ } 288 }; 289 MODULE_DEVICE_TABLE(platform, hid_humidity_ids); 290 291 static struct platform_driver hid_humidity_platform_driver = { 292 .id_table = hid_humidity_ids, 293 .driver = { 294 .name = KBUILD_MODNAME, 295 .pm = &hid_sensor_pm_ops, 296 }, 297 .probe = hid_humidity_probe, 298 .remove = hid_humidity_remove, 299 }; 300 module_platform_driver(hid_humidity_platform_driver); 301 302 MODULE_DESCRIPTION("HID Environmental humidity sensor"); 303 MODULE_AUTHOR("Song Hongyan <hongyan.song@intel.com>"); 304 MODULE_LICENSE("GPL v2"); 305