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 hid_sensor_power_state(&press_state->common_attributes, 105 false); 106 } else { 107 *val = 0; 108 return -EINVAL; 109 } 110 ret_type = IIO_VAL_INT; 111 break; 112 case IIO_CHAN_INFO_SCALE: 113 *val = press_state->scale_pre_decml; 114 *val2 = press_state->scale_post_decml; 115 ret_type = press_state->scale_precision; 116 break; 117 case IIO_CHAN_INFO_OFFSET: 118 *val = press_state->value_offset; 119 ret_type = IIO_VAL_INT; 120 break; 121 case IIO_CHAN_INFO_SAMP_FREQ: 122 ret_type = hid_sensor_read_samp_freq_value( 123 &press_state->common_attributes, val, val2); 124 break; 125 case IIO_CHAN_INFO_HYSTERESIS: 126 ret_type = hid_sensor_read_raw_hyst_value( 127 &press_state->common_attributes, val, val2); 128 break; 129 default: 130 ret_type = -EINVAL; 131 break; 132 } 133 134 return ret_type; 135 } 136 137 /* Channel write_raw handler */ 138 static int press_write_raw(struct iio_dev *indio_dev, 139 struct iio_chan_spec const *chan, 140 int val, 141 int val2, 142 long mask) 143 { 144 struct press_state *press_state = iio_priv(indio_dev); 145 int ret = 0; 146 147 switch (mask) { 148 case IIO_CHAN_INFO_SAMP_FREQ: 149 ret = hid_sensor_write_samp_freq_value( 150 &press_state->common_attributes, val, val2); 151 break; 152 case IIO_CHAN_INFO_HYSTERESIS: 153 ret = hid_sensor_write_raw_hyst_value( 154 &press_state->common_attributes, val, val2); 155 break; 156 default: 157 ret = -EINVAL; 158 } 159 160 return ret; 161 } 162 163 static const struct iio_info press_info = { 164 .driver_module = THIS_MODULE, 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 struct iio_chan_spec *channels; 265 266 indio_dev = devm_iio_device_alloc(&pdev->dev, 267 sizeof(struct press_state)); 268 if (!indio_dev) 269 return -ENOMEM; 270 platform_set_drvdata(pdev, indio_dev); 271 272 press_state = iio_priv(indio_dev); 273 press_state->common_attributes.hsdev = hsdev; 274 press_state->common_attributes.pdev = pdev; 275 276 ret = hid_sensor_parse_common_attributes(hsdev, 277 HID_USAGE_SENSOR_PRESSURE, 278 &press_state->common_attributes); 279 if (ret) { 280 dev_err(&pdev->dev, "failed to setup common attributes\n"); 281 return ret; 282 } 283 284 channels = kmemdup(press_channels, sizeof(press_channels), GFP_KERNEL); 285 if (!channels) { 286 dev_err(&pdev->dev, "failed to duplicate channels\n"); 287 return -ENOMEM; 288 } 289 290 ret = press_parse_report(pdev, hsdev, 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->channels = channels; 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 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