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 35struct 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 */ 47static const struct iio_chan_spec press_channels[] = { 48 { 49 .type = IIO_PRESSURE, 50 .modified = 1, 51 .channel2 = IIO_NO_MOD, 52 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), 53 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) | 54 BIT(IIO_CHAN_INFO_SCALE) | 55 BIT(IIO_CHAN_INFO_SAMP_FREQ) | 56 BIT(IIO_CHAN_INFO_HYSTERESIS), 57 .scan_index = CHANNEL_SCAN_INDEX_PRESSURE, 58 } 59}; 60 61/* Adjust channel real bits based on report descriptor */ 62static void press_adjust_channel_bit_mask(struct iio_chan_spec *channels, 63 int channel, int size) 64{ 65 channels[channel].scan_type.sign = 's'; 66 /* Real storage bits will change based on the report desc. */ 67 channels[channel].scan_type.realbits = size * 8; 68 /* Maximum size of a sample to capture is u32 */ 69 channels[channel].scan_type.storagebits = sizeof(u32) * 8; 70} 71 72/* Channel read_raw handler */ 73static int press_read_raw(struct iio_dev *indio_dev, 74 struct iio_chan_spec const *chan, 75 int *val, int *val2, 76 long mask) 77{ 78 struct press_state *press_state = iio_priv(indio_dev); 79 int report_id = -1; 80 u32 address; 81 int ret_type; 82 s32 poll_value; 83 84 *val = 0; 85 *val2 = 0; 86 switch (mask) { 87 case IIO_CHAN_INFO_RAW: 88 switch (chan->scan_index) { 89 case CHANNEL_SCAN_INDEX_PRESSURE: 90 report_id = press_state->press_attr.report_id; 91 address = 92 HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE; 93 break; 94 default: 95 report_id = -1; 96 break; 97 } 98 if (report_id >= 0) { 99 poll_value = hid_sensor_read_poll_value( 100 &press_state->common_attributes); 101 if (poll_value < 0) 102 return -EINVAL; 103 hid_sensor_power_state(&press_state->common_attributes, 104 true); 105 106 msleep_interruptible(poll_value * 2); 107 108 *val = sensor_hub_input_attr_get_raw_value( 109 press_state->common_attributes.hsdev, 110 HID_USAGE_SENSOR_PRESSURE, address, 111 report_id); 112 hid_sensor_power_state(&press_state->common_attributes, 113 false); 114 } else { 115 *val = 0; 116 return -EINVAL; 117 } 118 ret_type = IIO_VAL_INT; 119 break; 120 case IIO_CHAN_INFO_SCALE: 121 *val = press_state->scale_pre_decml; 122 *val2 = press_state->scale_post_decml; 123 ret_type = press_state->scale_precision; 124 break; 125 case IIO_CHAN_INFO_OFFSET: 126 *val = press_state->value_offset; 127 ret_type = IIO_VAL_INT; 128 break; 129 case IIO_CHAN_INFO_SAMP_FREQ: 130 ret_type = hid_sensor_read_samp_freq_value( 131 &press_state->common_attributes, val, val2); 132 break; 133 case IIO_CHAN_INFO_HYSTERESIS: 134 ret_type = hid_sensor_read_raw_hyst_value( 135 &press_state->common_attributes, val, val2); 136 break; 137 default: 138 ret_type = -EINVAL; 139 break; 140 } 141 142 return ret_type; 143} 144 145/* Channel write_raw handler */ 146static int press_write_raw(struct iio_dev *indio_dev, 147 struct iio_chan_spec const *chan, 148 int val, 149 int val2, 150 long mask) 151{ 152 struct press_state *press_state = iio_priv(indio_dev); 153 int ret = 0; 154 155 switch (mask) { 156 case IIO_CHAN_INFO_SAMP_FREQ: 157 ret = hid_sensor_write_samp_freq_value( 158 &press_state->common_attributes, val, val2); 159 break; 160 case IIO_CHAN_INFO_HYSTERESIS: 161 ret = hid_sensor_write_raw_hyst_value( 162 &press_state->common_attributes, val, val2); 163 break; 164 default: 165 ret = -EINVAL; 166 } 167 168 return ret; 169} 170 171static const struct iio_info press_info = { 172 .driver_module = THIS_MODULE, 173 .read_raw = &press_read_raw, 174 .write_raw = &press_write_raw, 175}; 176 177/* Function to push data to buffer */ 178static void hid_sensor_push_data(struct iio_dev *indio_dev, const void *data, 179 int len) 180{ 181 dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n"); 182 iio_push_to_buffers(indio_dev, data); 183} 184 185/* Callback handler to send event after all samples are received and captured */ 186static int press_proc_event(struct hid_sensor_hub_device *hsdev, 187 unsigned usage_id, 188 void *priv) 189{ 190 struct iio_dev *indio_dev = platform_get_drvdata(priv); 191 struct press_state *press_state = iio_priv(indio_dev); 192 193 dev_dbg(&indio_dev->dev, "press_proc_event\n"); 194 if (atomic_read(&press_state->common_attributes.data_ready)) 195 hid_sensor_push_data(indio_dev, 196 &press_state->press_data, 197 sizeof(press_state->press_data)); 198 199 return 0; 200} 201 202/* Capture samples in local storage */ 203static int press_capture_sample(struct hid_sensor_hub_device *hsdev, 204 unsigned usage_id, 205 size_t raw_len, char *raw_data, 206 void *priv) 207{ 208 struct iio_dev *indio_dev = platform_get_drvdata(priv); 209 struct press_state *press_state = iio_priv(indio_dev); 210 int ret = -EINVAL; 211 212 switch (usage_id) { 213 case HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE: 214 press_state->press_data = *(u32 *)raw_data; 215 ret = 0; 216 break; 217 default: 218 break; 219 } 220 221 return ret; 222} 223 224/* Parse report which is specific to an usage id*/ 225static int press_parse_report(struct platform_device *pdev, 226 struct hid_sensor_hub_device *hsdev, 227 struct iio_chan_spec *channels, 228 unsigned usage_id, 229 struct press_state *st) 230{ 231 int ret; 232 233 ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT, 234 usage_id, 235 HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE, 236 &st->press_attr); 237 if (ret < 0) 238 return ret; 239 press_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_PRESSURE, 240 st->press_attr.size); 241 242 dev_dbg(&pdev->dev, "press %x:%x\n", st->press_attr.index, 243 st->press_attr.report_id); 244 245 st->scale_precision = hid_sensor_format_scale( 246 HID_USAGE_SENSOR_PRESSURE, 247 &st->press_attr, 248 &st->scale_pre_decml, &st->scale_post_decml); 249 250 /* Set Sensitivity field ids, when there is no individual modifier */ 251 if (st->common_attributes.sensitivity.index < 0) { 252 sensor_hub_input_get_attribute_info(hsdev, 253 HID_FEATURE_REPORT, usage_id, 254 HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS | 255 HID_USAGE_SENSOR_DATA_ATMOSPHERIC_PRESSURE, 256 &st->common_attributes.sensitivity); 257 dev_dbg(&pdev->dev, "Sensitivity index:report %d:%d\n", 258 st->common_attributes.sensitivity.index, 259 st->common_attributes.sensitivity.report_id); 260 } 261 return ret; 262} 263 264/* Function to initialize the processing for usage id */ 265static int hid_press_probe(struct platform_device *pdev) 266{ 267 int ret = 0; 268 static const char *name = "press"; 269 struct iio_dev *indio_dev; 270 struct press_state *press_state; 271 struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data; 272 struct iio_chan_spec *channels; 273 274 indio_dev = devm_iio_device_alloc(&pdev->dev, 275 sizeof(struct press_state)); 276 if (!indio_dev) 277 return -ENOMEM; 278 platform_set_drvdata(pdev, indio_dev); 279 280 press_state = iio_priv(indio_dev); 281 press_state->common_attributes.hsdev = hsdev; 282 press_state->common_attributes.pdev = pdev; 283 284 ret = hid_sensor_parse_common_attributes(hsdev, 285 HID_USAGE_SENSOR_PRESSURE, 286 &press_state->common_attributes); 287 if (ret) { 288 dev_err(&pdev->dev, "failed to setup common attributes\n"); 289 return ret; 290 } 291 292 channels = kmemdup(press_channels, sizeof(press_channels), GFP_KERNEL); 293 if (!channels) { 294 dev_err(&pdev->dev, "failed to duplicate channels\n"); 295 return -ENOMEM; 296 } 297 298 ret = press_parse_report(pdev, hsdev, channels, 299 HID_USAGE_SENSOR_PRESSURE, press_state); 300 if (ret) { 301 dev_err(&pdev->dev, "failed to setup attributes\n"); 302 goto error_free_dev_mem; 303 } 304 305 indio_dev->channels = channels; 306 indio_dev->num_channels = 307 ARRAY_SIZE(press_channels); 308 indio_dev->dev.parent = &pdev->dev; 309 indio_dev->info = &press_info; 310 indio_dev->name = name; 311 indio_dev->modes = INDIO_DIRECT_MODE; 312 313 ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time, 314 NULL, NULL); 315 if (ret) { 316 dev_err(&pdev->dev, "failed to initialize trigger buffer\n"); 317 goto error_free_dev_mem; 318 } 319 atomic_set(&press_state->common_attributes.data_ready, 0); 320 ret = hid_sensor_setup_trigger(indio_dev, name, 321 &press_state->common_attributes); 322 if (ret) { 323 dev_err(&pdev->dev, "trigger setup failed\n"); 324 goto error_unreg_buffer_funcs; 325 } 326 327 ret = iio_device_register(indio_dev); 328 if (ret) { 329 dev_err(&pdev->dev, "device register failed\n"); 330 goto error_remove_trigger; 331 } 332 333 press_state->callbacks.send_event = press_proc_event; 334 press_state->callbacks.capture_sample = press_capture_sample; 335 press_state->callbacks.pdev = pdev; 336 ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_PRESSURE, 337 &press_state->callbacks); 338 if (ret < 0) { 339 dev_err(&pdev->dev, "callback reg failed\n"); 340 goto error_iio_unreg; 341 } 342 343 return ret; 344 345error_iio_unreg: 346 iio_device_unregister(indio_dev); 347error_remove_trigger: 348 hid_sensor_remove_trigger(&press_state->common_attributes); 349error_unreg_buffer_funcs: 350 iio_triggered_buffer_cleanup(indio_dev); 351error_free_dev_mem: 352 kfree(indio_dev->channels); 353 return ret; 354} 355 356/* Function to deinitialize the processing for usage id */ 357static int hid_press_remove(struct platform_device *pdev) 358{ 359 struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data; 360 struct iio_dev *indio_dev = platform_get_drvdata(pdev); 361 struct press_state *press_state = iio_priv(indio_dev); 362 363 sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_PRESSURE); 364 iio_device_unregister(indio_dev); 365 hid_sensor_remove_trigger(&press_state->common_attributes); 366 iio_triggered_buffer_cleanup(indio_dev); 367 kfree(indio_dev->channels); 368 369 return 0; 370} 371 372static struct platform_device_id hid_press_ids[] = { 373 { 374 /* Format: HID-SENSOR-usage_id_in_hex_lowercase */ 375 .name = "HID-SENSOR-200031", 376 }, 377 { /* sentinel */ } 378}; 379MODULE_DEVICE_TABLE(platform, hid_press_ids); 380 381static struct platform_driver hid_press_platform_driver = { 382 .id_table = hid_press_ids, 383 .driver = { 384 .name = KBUILD_MODNAME, 385 }, 386 .probe = hid_press_probe, 387 .remove = hid_press_remove, 388}; 389module_platform_driver(hid_press_platform_driver); 390 391MODULE_DESCRIPTION("HID Sensor Pressure"); 392MODULE_AUTHOR("Archana Patni <archana.patni@intel.com>"); 393MODULE_LICENSE("GPL"); 394