1 /* 2 * HID Sensors Driver 3 * Copyright (c) 2014, Intel Corporation. 4 * 5 * This program is free software; you can redistribute it and/or modify it 6 * under the terms and conditions of the GNU General Public License, 7 * version 2, as published by the Free Software Foundation. 8 * 9 * This program is distributed in the hope it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 12 * more details. 13 * 14 * You should have received a copy of the GNU General Public License along with 15 * this program. 16 * 17 */ 18 #include <linux/device.h> 19 #include <linux/platform_device.h> 20 #include <linux/module.h> 21 #include <linux/interrupt.h> 22 #include <linux/irq.h> 23 #include <linux/slab.h> 24 #include <linux/delay.h> 25 #include <linux/hid-sensor-hub.h> 26 #include <linux/iio/iio.h> 27 #include <linux/iio/sysfs.h> 28 #include <linux/iio/buffer.h> 29 #include <linux/iio/trigger_consumer.h> 30 #include <linux/iio/triggered_buffer.h> 31 #include "../common/hid-sensors/hid-sensor-trigger.h" 32 33 #define CHANNEL_SCAN_INDEX_PRESSURE 0 34 35 struct press_state { 36 struct hid_sensor_hub_callbacks callbacks; 37 struct hid_sensor_common common_attributes; 38 struct hid_sensor_hub_attribute_info press_attr; 39 u32 press_data; 40 int scale_pre_decml; 41 int scale_post_decml; 42 int scale_precision; 43 int value_offset; 44 }; 45 46 /* Channel definitions */ 47 static const struct iio_chan_spec press_channels[] = { 48 { 49 .type = IIO_PRESSURE, 50 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), 51 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) | 52 BIT(IIO_CHAN_INFO_SCALE) | 53 BIT(IIO_CHAN_INFO_SAMP_FREQ) | 54 BIT(IIO_CHAN_INFO_HYSTERESIS), 55 .scan_index = CHANNEL_SCAN_INDEX_PRESSURE, 56 } 57 }; 58 59 /* Adjust channel real bits based on report descriptor */ 60 static void press_adjust_channel_bit_mask(struct iio_chan_spec *channels, 61 int channel, int size) 62 { 63 channels[channel].scan_type.sign = 's'; 64 /* Real storage bits will change based on the report desc. */ 65 channels[channel].scan_type.realbits = size * 8; 66 /* Maximum size of a sample to capture is u32 */ 67 channels[channel].scan_type.storagebits = sizeof(u32) * 8; 68 } 69 70 /* Channel read_raw handler */ 71 static int press_read_raw(struct iio_dev *indio_dev, 72 struct iio_chan_spec const *chan, 73 int *val, int *val2, 74 long mask) 75 { 76 struct press_state *press_state = iio_priv(indio_dev); 77 int report_id = -1; 78 u32 address; 79 int ret_type; 80 81 *val = 0; 82 *val2 = 0; 83 switch (mask) { 84 case IIO_CHAN_INFO_RAW: 85 switch (chan->scan_index) { 86 case CHANNEL_SCAN_INDEX_PRESSURE: 87 report_id = press_state->press_attr.report_id; 88 address = 89 HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE; 90 break; 91 default: 92 report_id = -1; 93 break; 94 } 95 if (report_id >= 0) { 96 hid_sensor_power_state(&press_state->common_attributes, 97 true); 98 *val = sensor_hub_input_attr_get_raw_value( 99 press_state->common_attributes.hsdev, 100 HID_USAGE_SENSOR_PRESSURE, address, 101 report_id, 102 SENSOR_HUB_SYNC); 103 hid_sensor_power_state(&press_state->common_attributes, 104 false); 105 } else { 106 *val = 0; 107 return -EINVAL; 108 } 109 ret_type = IIO_VAL_INT; 110 break; 111 case IIO_CHAN_INFO_SCALE: 112 *val = press_state->scale_pre_decml; 113 *val2 = press_state->scale_post_decml; 114 ret_type = press_state->scale_precision; 115 break; 116 case IIO_CHAN_INFO_OFFSET: 117 *val = press_state->value_offset; 118 ret_type = IIO_VAL_INT; 119 break; 120 case IIO_CHAN_INFO_SAMP_FREQ: 121 ret_type = hid_sensor_read_samp_freq_value( 122 &press_state->common_attributes, val, val2); 123 break; 124 case IIO_CHAN_INFO_HYSTERESIS: 125 ret_type = hid_sensor_read_raw_hyst_value( 126 &press_state->common_attributes, val, val2); 127 break; 128 default: 129 ret_type = -EINVAL; 130 break; 131 } 132 133 return ret_type; 134 } 135 136 /* Channel write_raw handler */ 137 static int press_write_raw(struct iio_dev *indio_dev, 138 struct iio_chan_spec const *chan, 139 int val, 140 int val2, 141 long mask) 142 { 143 struct press_state *press_state = iio_priv(indio_dev); 144 int ret = 0; 145 146 switch (mask) { 147 case IIO_CHAN_INFO_SAMP_FREQ: 148 ret = hid_sensor_write_samp_freq_value( 149 &press_state->common_attributes, val, val2); 150 break; 151 case IIO_CHAN_INFO_HYSTERESIS: 152 ret = hid_sensor_write_raw_hyst_value( 153 &press_state->common_attributes, val, val2); 154 break; 155 default: 156 ret = -EINVAL; 157 } 158 159 return ret; 160 } 161 162 static const struct iio_info press_info = { 163 .read_raw = &press_read_raw, 164 .write_raw = &press_write_raw, 165 }; 166 167 /* Function to push data to buffer */ 168 static void hid_sensor_push_data(struct iio_dev *indio_dev, const void *data, 169 int len) 170 { 171 dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n"); 172 iio_push_to_buffers(indio_dev, data); 173 } 174 175 /* Callback handler to send event after all samples are received and captured */ 176 static int press_proc_event(struct hid_sensor_hub_device *hsdev, 177 unsigned usage_id, 178 void *priv) 179 { 180 struct iio_dev *indio_dev = platform_get_drvdata(priv); 181 struct press_state *press_state = iio_priv(indio_dev); 182 183 dev_dbg(&indio_dev->dev, "press_proc_event\n"); 184 if (atomic_read(&press_state->common_attributes.data_ready)) 185 hid_sensor_push_data(indio_dev, 186 &press_state->press_data, 187 sizeof(press_state->press_data)); 188 189 return 0; 190 } 191 192 /* Capture samples in local storage */ 193 static int press_capture_sample(struct hid_sensor_hub_device *hsdev, 194 unsigned usage_id, 195 size_t raw_len, char *raw_data, 196 void *priv) 197 { 198 struct iio_dev *indio_dev = platform_get_drvdata(priv); 199 struct press_state *press_state = iio_priv(indio_dev); 200 int ret = -EINVAL; 201 202 switch (usage_id) { 203 case HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE: 204 press_state->press_data = *(u32 *)raw_data; 205 ret = 0; 206 break; 207 default: 208 break; 209 } 210 211 return ret; 212 } 213 214 /* Parse report which is specific to an usage id*/ 215 static int press_parse_report(struct platform_device *pdev, 216 struct hid_sensor_hub_device *hsdev, 217 struct iio_chan_spec *channels, 218 unsigned usage_id, 219 struct press_state *st) 220 { 221 int ret; 222 223 ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT, 224 usage_id, 225 HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE, 226 &st->press_attr); 227 if (ret < 0) 228 return ret; 229 press_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_PRESSURE, 230 st->press_attr.size); 231 232 dev_dbg(&pdev->dev, "press %x:%x\n", st->press_attr.index, 233 st->press_attr.report_id); 234 235 st->scale_precision = hid_sensor_format_scale( 236 HID_USAGE_SENSOR_PRESSURE, 237 &st->press_attr, 238 &st->scale_pre_decml, &st->scale_post_decml); 239 240 /* Set Sensitivity field ids, when there is no individual modifier */ 241 if (st->common_attributes.sensitivity.index < 0) { 242 sensor_hub_input_get_attribute_info(hsdev, 243 HID_FEATURE_REPORT, usage_id, 244 HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS | 245 HID_USAGE_SENSOR_DATA_ATMOSPHERIC_PRESSURE, 246 &st->common_attributes.sensitivity); 247 dev_dbg(&pdev->dev, "Sensitivity index:report %d:%d\n", 248 st->common_attributes.sensitivity.index, 249 st->common_attributes.sensitivity.report_id); 250 } 251 return ret; 252 } 253 254 /* Function to initialize the processing for usage id */ 255 static int hid_press_probe(struct platform_device *pdev) 256 { 257 int ret = 0; 258 static const char *name = "press"; 259 struct iio_dev *indio_dev; 260 struct press_state *press_state; 261 struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data; 262 263 indio_dev = devm_iio_device_alloc(&pdev->dev, 264 sizeof(struct press_state)); 265 if (!indio_dev) 266 return -ENOMEM; 267 platform_set_drvdata(pdev, indio_dev); 268 269 press_state = iio_priv(indio_dev); 270 press_state->common_attributes.hsdev = hsdev; 271 press_state->common_attributes.pdev = pdev; 272 273 ret = hid_sensor_parse_common_attributes(hsdev, 274 HID_USAGE_SENSOR_PRESSURE, 275 &press_state->common_attributes); 276 if (ret) { 277 dev_err(&pdev->dev, "failed to setup common attributes\n"); 278 return ret; 279 } 280 281 indio_dev->channels = kmemdup(press_channels, sizeof(press_channels), 282 GFP_KERNEL); 283 if (!indio_dev->channels) { 284 dev_err(&pdev->dev, "failed to duplicate channels\n"); 285 return -ENOMEM; 286 } 287 288 ret = press_parse_report(pdev, hsdev, 289 (struct iio_chan_spec *)indio_dev->channels, 290 HID_USAGE_SENSOR_PRESSURE, press_state); 291 if (ret) { 292 dev_err(&pdev->dev, "failed to setup attributes\n"); 293 goto error_free_dev_mem; 294 } 295 296 indio_dev->num_channels = 297 ARRAY_SIZE(press_channels); 298 indio_dev->dev.parent = &pdev->dev; 299 indio_dev->info = &press_info; 300 indio_dev->name = name; 301 indio_dev->modes = INDIO_DIRECT_MODE; 302 303 ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time, 304 NULL, NULL); 305 if (ret) { 306 dev_err(&pdev->dev, "failed to initialize trigger buffer\n"); 307 goto error_free_dev_mem; 308 } 309 atomic_set(&press_state->common_attributes.data_ready, 0); 310 ret = hid_sensor_setup_trigger(indio_dev, name, 311 &press_state->common_attributes); 312 if (ret) { 313 dev_err(&pdev->dev, "trigger setup failed\n"); 314 goto error_unreg_buffer_funcs; 315 } 316 317 ret = iio_device_register(indio_dev); 318 if (ret) { 319 dev_err(&pdev->dev, "device register failed\n"); 320 goto error_remove_trigger; 321 } 322 323 press_state->callbacks.send_event = press_proc_event; 324 press_state->callbacks.capture_sample = press_capture_sample; 325 press_state->callbacks.pdev = pdev; 326 ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_PRESSURE, 327 &press_state->callbacks); 328 if (ret < 0) { 329 dev_err(&pdev->dev, "callback reg failed\n"); 330 goto error_iio_unreg; 331 } 332 333 return ret; 334 335 error_iio_unreg: 336 iio_device_unregister(indio_dev); 337 error_remove_trigger: 338 hid_sensor_remove_trigger(&press_state->common_attributes); 339 error_unreg_buffer_funcs: 340 iio_triggered_buffer_cleanup(indio_dev); 341 error_free_dev_mem: 342 kfree(indio_dev->channels); 343 return ret; 344 } 345 346 /* Function to deinitialize the processing for usage id */ 347 static int hid_press_remove(struct platform_device *pdev) 348 { 349 struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data; 350 struct iio_dev *indio_dev = platform_get_drvdata(pdev); 351 struct press_state *press_state = iio_priv(indio_dev); 352 353 sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_PRESSURE); 354 iio_device_unregister(indio_dev); 355 hid_sensor_remove_trigger(&press_state->common_attributes); 356 iio_triggered_buffer_cleanup(indio_dev); 357 kfree(indio_dev->channels); 358 359 return 0; 360 } 361 362 static const struct platform_device_id hid_press_ids[] = { 363 { 364 /* Format: HID-SENSOR-usage_id_in_hex_lowercase */ 365 .name = "HID-SENSOR-200031", 366 }, 367 { /* sentinel */ } 368 }; 369 MODULE_DEVICE_TABLE(platform, hid_press_ids); 370 371 static struct platform_driver hid_press_platform_driver = { 372 .id_table = hid_press_ids, 373 .driver = { 374 .name = KBUILD_MODNAME, 375 .pm = &hid_sensor_pm_ops, 376 }, 377 .probe = hid_press_probe, 378 .remove = hid_press_remove, 379 }; 380 module_platform_driver(hid_press_platform_driver); 381 382 MODULE_DESCRIPTION("HID Sensor Pressure"); 383 MODULE_AUTHOR("Archana Patni <archana.patni@intel.com>"); 384 MODULE_LICENSE("GPL"); 385