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