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 .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 */ 60static 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 */ 71static 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 */ 137static 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 162static const struct iio_info press_info = { 163 .driver_module = THIS_MODULE, 164 .read_raw = &press_read_raw, 165 .write_raw = &press_write_raw, 166}; 167 168/* Function to push data to buffer */ 169static void hid_sensor_push_data(struct iio_dev *indio_dev, const void *data, 170 int len) 171{ 172 dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n"); 173 iio_push_to_buffers(indio_dev, data); 174} 175 176/* Callback handler to send event after all samples are received and captured */ 177static int press_proc_event(struct hid_sensor_hub_device *hsdev, 178 unsigned usage_id, 179 void *priv) 180{ 181 struct iio_dev *indio_dev = platform_get_drvdata(priv); 182 struct press_state *press_state = iio_priv(indio_dev); 183 184 dev_dbg(&indio_dev->dev, "press_proc_event\n"); 185 if (atomic_read(&press_state->common_attributes.data_ready)) 186 hid_sensor_push_data(indio_dev, 187 &press_state->press_data, 188 sizeof(press_state->press_data)); 189 190 return 0; 191} 192 193/* Capture samples in local storage */ 194static int press_capture_sample(struct hid_sensor_hub_device *hsdev, 195 unsigned usage_id, 196 size_t raw_len, char *raw_data, 197 void *priv) 198{ 199 struct iio_dev *indio_dev = platform_get_drvdata(priv); 200 struct press_state *press_state = iio_priv(indio_dev); 201 int ret = -EINVAL; 202 203 switch (usage_id) { 204 case HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE: 205 press_state->press_data = *(u32 *)raw_data; 206 ret = 0; 207 break; 208 default: 209 break; 210 } 211 212 return ret; 213} 214 215/* Parse report which is specific to an usage id*/ 216static int press_parse_report(struct platform_device *pdev, 217 struct hid_sensor_hub_device *hsdev, 218 struct iio_chan_spec *channels, 219 unsigned usage_id, 220 struct press_state *st) 221{ 222 int ret; 223 224 ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT, 225 usage_id, 226 HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE, 227 &st->press_attr); 228 if (ret < 0) 229 return ret; 230 press_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_PRESSURE, 231 st->press_attr.size); 232 233 dev_dbg(&pdev->dev, "press %x:%x\n", st->press_attr.index, 234 st->press_attr.report_id); 235 236 st->scale_precision = hid_sensor_format_scale( 237 HID_USAGE_SENSOR_PRESSURE, 238 &st->press_attr, 239 &st->scale_pre_decml, &st->scale_post_decml); 240 241 /* Set Sensitivity field ids, when there is no individual modifier */ 242 if (st->common_attributes.sensitivity.index < 0) { 243 sensor_hub_input_get_attribute_info(hsdev, 244 HID_FEATURE_REPORT, usage_id, 245 HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS | 246 HID_USAGE_SENSOR_DATA_ATMOSPHERIC_PRESSURE, 247 &st->common_attributes.sensitivity); 248 dev_dbg(&pdev->dev, "Sensitivity index:report %d:%d\n", 249 st->common_attributes.sensitivity.index, 250 st->common_attributes.sensitivity.report_id); 251 } 252 return ret; 253} 254 255/* Function to initialize the processing for usage id */ 256static int hid_press_probe(struct platform_device *pdev) 257{ 258 int ret = 0; 259 static const char *name = "press"; 260 struct iio_dev *indio_dev; 261 struct press_state *press_state; 262 struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data; 263 264 indio_dev = devm_iio_device_alloc(&pdev->dev, 265 sizeof(struct press_state)); 266 if (!indio_dev) 267 return -ENOMEM; 268 platform_set_drvdata(pdev, indio_dev); 269 270 press_state = iio_priv(indio_dev); 271 press_state->common_attributes.hsdev = hsdev; 272 press_state->common_attributes.pdev = pdev; 273 274 ret = hid_sensor_parse_common_attributes(hsdev, 275 HID_USAGE_SENSOR_PRESSURE, 276 &press_state->common_attributes); 277 if (ret) { 278 dev_err(&pdev->dev, "failed to setup common attributes\n"); 279 return ret; 280 } 281 282 indio_dev->channels = kmemdup(press_channels, sizeof(press_channels), 283 GFP_KERNEL); 284 if (!indio_dev->channels) { 285 dev_err(&pdev->dev, "failed to duplicate channels\n"); 286 return -ENOMEM; 287 } 288 289 ret = press_parse_report(pdev, hsdev, 290 (struct iio_chan_spec *)indio_dev->channels, 291 HID_USAGE_SENSOR_PRESSURE, press_state); 292 if (ret) { 293 dev_err(&pdev->dev, "failed to setup attributes\n"); 294 goto error_free_dev_mem; 295 } 296 297 indio_dev->num_channels = 298 ARRAY_SIZE(press_channels); 299 indio_dev->dev.parent = &pdev->dev; 300 indio_dev->info = &press_info; 301 indio_dev->name = name; 302 indio_dev->modes = INDIO_DIRECT_MODE; 303 304 ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time, 305 NULL, NULL); 306 if (ret) { 307 dev_err(&pdev->dev, "failed to initialize trigger buffer\n"); 308 goto error_free_dev_mem; 309 } 310 atomic_set(&press_state->common_attributes.data_ready, 0); 311 ret = hid_sensor_setup_trigger(indio_dev, name, 312 &press_state->common_attributes); 313 if (ret) { 314 dev_err(&pdev->dev, "trigger setup failed\n"); 315 goto error_unreg_buffer_funcs; 316 } 317 318 ret = iio_device_register(indio_dev); 319 if (ret) { 320 dev_err(&pdev->dev, "device register failed\n"); 321 goto error_remove_trigger; 322 } 323 324 press_state->callbacks.send_event = press_proc_event; 325 press_state->callbacks.capture_sample = press_capture_sample; 326 press_state->callbacks.pdev = pdev; 327 ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_PRESSURE, 328 &press_state->callbacks); 329 if (ret < 0) { 330 dev_err(&pdev->dev, "callback reg failed\n"); 331 goto error_iio_unreg; 332 } 333 334 return ret; 335 336error_iio_unreg: 337 iio_device_unregister(indio_dev); 338error_remove_trigger: 339 hid_sensor_remove_trigger(&press_state->common_attributes); 340error_unreg_buffer_funcs: 341 iio_triggered_buffer_cleanup(indio_dev); 342error_free_dev_mem: 343 kfree(indio_dev->channels); 344 return ret; 345} 346 347/* Function to deinitialize the processing for usage id */ 348static int hid_press_remove(struct platform_device *pdev) 349{ 350 struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data; 351 struct iio_dev *indio_dev = platform_get_drvdata(pdev); 352 struct press_state *press_state = iio_priv(indio_dev); 353 354 sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_PRESSURE); 355 iio_device_unregister(indio_dev); 356 hid_sensor_remove_trigger(&press_state->common_attributes); 357 iio_triggered_buffer_cleanup(indio_dev); 358 kfree(indio_dev->channels); 359 360 return 0; 361} 362 363static const struct platform_device_id hid_press_ids[] = { 364 { 365 /* Format: HID-SENSOR-usage_id_in_hex_lowercase */ 366 .name = "HID-SENSOR-200031", 367 }, 368 { /* sentinel */ } 369}; 370MODULE_DEVICE_TABLE(platform, hid_press_ids); 371 372static struct platform_driver hid_press_platform_driver = { 373 .id_table = hid_press_ids, 374 .driver = { 375 .name = KBUILD_MODNAME, 376 .pm = &hid_sensor_pm_ops, 377 }, 378 .probe = hid_press_probe, 379 .remove = hid_press_remove, 380}; 381module_platform_driver(hid_press_platform_driver); 382 383MODULE_DESCRIPTION("HID Sensor Pressure"); 384MODULE_AUTHOR("Archana Patni <archana.patni@intel.com>"); 385MODULE_LICENSE("GPL"); 386