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 .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 */ 62 static 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 */ 73 static 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 83 *val = 0; 84 *val2 = 0; 85 switch (mask) { 86 case IIO_CHAN_INFO_RAW: 87 switch (chan->scan_index) { 88 case CHANNEL_SCAN_INDEX_PRESSURE: 89 report_id = press_state->press_attr.report_id; 90 address = 91 HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE; 92 break; 93 default: 94 report_id = -1; 95 break; 96 } 97 if (report_id >= 0) { 98 hid_sensor_power_state(&press_state->common_attributes, 99 true); 100 *val = sensor_hub_input_attr_get_raw_value( 101 press_state->common_attributes.hsdev, 102 HID_USAGE_SENSOR_PRESSURE, address, 103 report_id, 104 SENSOR_HUB_SYNC); 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 .driver_module = THIS_MODULE, 166 .read_raw = &press_read_raw, 167 .write_raw = &press_write_raw, 168 }; 169 170 /* Function to push data to buffer */ 171 static void hid_sensor_push_data(struct iio_dev *indio_dev, const void *data, 172 int len) 173 { 174 dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n"); 175 iio_push_to_buffers(indio_dev, data); 176 } 177 178 /* Callback handler to send event after all samples are received and captured */ 179 static int press_proc_event(struct hid_sensor_hub_device *hsdev, 180 unsigned usage_id, 181 void *priv) 182 { 183 struct iio_dev *indio_dev = platform_get_drvdata(priv); 184 struct press_state *press_state = iio_priv(indio_dev); 185 186 dev_dbg(&indio_dev->dev, "press_proc_event\n"); 187 if (atomic_read(&press_state->common_attributes.data_ready)) 188 hid_sensor_push_data(indio_dev, 189 &press_state->press_data, 190 sizeof(press_state->press_data)); 191 192 return 0; 193 } 194 195 /* Capture samples in local storage */ 196 static int press_capture_sample(struct hid_sensor_hub_device *hsdev, 197 unsigned usage_id, 198 size_t raw_len, char *raw_data, 199 void *priv) 200 { 201 struct iio_dev *indio_dev = platform_get_drvdata(priv); 202 struct press_state *press_state = iio_priv(indio_dev); 203 int ret = -EINVAL; 204 205 switch (usage_id) { 206 case HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE: 207 press_state->press_data = *(u32 *)raw_data; 208 ret = 0; 209 break; 210 default: 211 break; 212 } 213 214 return ret; 215 } 216 217 /* Parse report which is specific to an usage id*/ 218 static int press_parse_report(struct platform_device *pdev, 219 struct hid_sensor_hub_device *hsdev, 220 struct iio_chan_spec *channels, 221 unsigned usage_id, 222 struct press_state *st) 223 { 224 int ret; 225 226 ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT, 227 usage_id, 228 HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE, 229 &st->press_attr); 230 if (ret < 0) 231 return ret; 232 press_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_PRESSURE, 233 st->press_attr.size); 234 235 dev_dbg(&pdev->dev, "press %x:%x\n", st->press_attr.index, 236 st->press_attr.report_id); 237 238 st->scale_precision = hid_sensor_format_scale( 239 HID_USAGE_SENSOR_PRESSURE, 240 &st->press_attr, 241 &st->scale_pre_decml, &st->scale_post_decml); 242 243 /* Set Sensitivity field ids, when there is no individual modifier */ 244 if (st->common_attributes.sensitivity.index < 0) { 245 sensor_hub_input_get_attribute_info(hsdev, 246 HID_FEATURE_REPORT, usage_id, 247 HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS | 248 HID_USAGE_SENSOR_DATA_ATMOSPHERIC_PRESSURE, 249 &st->common_attributes.sensitivity); 250 dev_dbg(&pdev->dev, "Sensitivity index:report %d:%d\n", 251 st->common_attributes.sensitivity.index, 252 st->common_attributes.sensitivity.report_id); 253 } 254 return ret; 255 } 256 257 /* Function to initialize the processing for usage id */ 258 static int hid_press_probe(struct platform_device *pdev) 259 { 260 int ret = 0; 261 static const char *name = "press"; 262 struct iio_dev *indio_dev; 263 struct press_state *press_state; 264 struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data; 265 struct iio_chan_spec *channels; 266 267 indio_dev = devm_iio_device_alloc(&pdev->dev, 268 sizeof(struct press_state)); 269 if (!indio_dev) 270 return -ENOMEM; 271 platform_set_drvdata(pdev, indio_dev); 272 273 press_state = iio_priv(indio_dev); 274 press_state->common_attributes.hsdev = hsdev; 275 press_state->common_attributes.pdev = pdev; 276 277 ret = hid_sensor_parse_common_attributes(hsdev, 278 HID_USAGE_SENSOR_PRESSURE, 279 &press_state->common_attributes); 280 if (ret) { 281 dev_err(&pdev->dev, "failed to setup common attributes\n"); 282 return ret; 283 } 284 285 channels = kmemdup(press_channels, sizeof(press_channels), GFP_KERNEL); 286 if (!channels) { 287 dev_err(&pdev->dev, "failed to duplicate channels\n"); 288 return -ENOMEM; 289 } 290 291 ret = press_parse_report(pdev, hsdev, 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->channels = channels; 299 indio_dev->num_channels = 300 ARRAY_SIZE(press_channels); 301 indio_dev->dev.parent = &pdev->dev; 302 indio_dev->info = &press_info; 303 indio_dev->name = name; 304 indio_dev->modes = INDIO_DIRECT_MODE; 305 306 ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time, 307 NULL, NULL); 308 if (ret) { 309 dev_err(&pdev->dev, "failed to initialize trigger buffer\n"); 310 goto error_free_dev_mem; 311 } 312 atomic_set(&press_state->common_attributes.data_ready, 0); 313 ret = hid_sensor_setup_trigger(indio_dev, name, 314 &press_state->common_attributes); 315 if (ret) { 316 dev_err(&pdev->dev, "trigger setup failed\n"); 317 goto error_unreg_buffer_funcs; 318 } 319 320 ret = iio_device_register(indio_dev); 321 if (ret) { 322 dev_err(&pdev->dev, "device register failed\n"); 323 goto error_remove_trigger; 324 } 325 326 press_state->callbacks.send_event = press_proc_event; 327 press_state->callbacks.capture_sample = press_capture_sample; 328 press_state->callbacks.pdev = pdev; 329 ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_PRESSURE, 330 &press_state->callbacks); 331 if (ret < 0) { 332 dev_err(&pdev->dev, "callback reg failed\n"); 333 goto error_iio_unreg; 334 } 335 336 return ret; 337 338 error_iio_unreg: 339 iio_device_unregister(indio_dev); 340 error_remove_trigger: 341 hid_sensor_remove_trigger(&press_state->common_attributes); 342 error_unreg_buffer_funcs: 343 iio_triggered_buffer_cleanup(indio_dev); 344 error_free_dev_mem: 345 kfree(indio_dev->channels); 346 return ret; 347 } 348 349 /* Function to deinitialize the processing for usage id */ 350 static int hid_press_remove(struct platform_device *pdev) 351 { 352 struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data; 353 struct iio_dev *indio_dev = platform_get_drvdata(pdev); 354 struct press_state *press_state = iio_priv(indio_dev); 355 356 sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_PRESSURE); 357 iio_device_unregister(indio_dev); 358 hid_sensor_remove_trigger(&press_state->common_attributes); 359 iio_triggered_buffer_cleanup(indio_dev); 360 kfree(indio_dev->channels); 361 362 return 0; 363 } 364 365 static struct platform_device_id hid_press_ids[] = { 366 { 367 /* Format: HID-SENSOR-usage_id_in_hex_lowercase */ 368 .name = "HID-SENSOR-200031", 369 }, 370 { /* sentinel */ } 371 }; 372 MODULE_DEVICE_TABLE(platform, hid_press_ids); 373 374 static struct platform_driver hid_press_platform_driver = { 375 .id_table = hid_press_ids, 376 .driver = { 377 .name = KBUILD_MODNAME, 378 .pm = &hid_sensor_pm_ops, 379 }, 380 .probe = hid_press_probe, 381 .remove = hid_press_remove, 382 }; 383 module_platform_driver(hid_press_platform_driver); 384 385 MODULE_DESCRIPTION("HID Sensor Pressure"); 386 MODULE_AUTHOR("Archana Patni <archana.patni@intel.com>"); 387 MODULE_LICENSE("GPL"); 388