drivers/iio/magnetometer/hid-sensor-magn-3d.c

   1 /*
   2  * HID Sensors Driver
   3  * Copyright (c) 2012, 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; if not, write to the Free Software Foundation, Inc.,
  16  * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
  17  *
  18  */
  19 #include <linux/device.h>
  20 #include <linux/platform_device.h>
  21 #include <linux/module.h>
  22 #include <linux/interrupt.h>
  23 #include <linux/irq.h>
  24 #include <linux/slab.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-attributes.h"
  32 #include "../common/hid-sensors/hid-sensor-trigger.h"
  33
  34 /*Format: HID-SENSOR-usage_id_in_hex*/
  35 /*Usage ID from spec for Magnetometer-3D: 0x200083*/
  36 #define DRIVER_NAME "HID-SENSOR-200083"
  37
  38 enum magn_3d_channel {
  39         CHANNEL_SCAN_INDEX_X,
  40         CHANNEL_SCAN_INDEX_Y,
  41         CHANNEL_SCAN_INDEX_Z,
  42         MAGN_3D_CHANNEL_MAX,
  43 };
  44
  45 struct magn_3d_state {
  46         struct hid_sensor_hub_callbacks callbacks;
  47         struct hid_sensor_iio_common common_attributes;
  48         struct hid_sensor_hub_attribute_info magn[MAGN_3D_CHANNEL_MAX];
  49         u32 magn_val[MAGN_3D_CHANNEL_MAX];
  50 };
  51
  52 static const u32 magn_3d_addresses[MAGN_3D_CHANNEL_MAX] = {
  53         HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_X_AXIS,
  54         HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_Y_AXIS,
  55         HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_Z_AXIS
  56 };
  57
  58 /* Channel definitions */
  59 static const struct iio_chan_spec magn_3d_channels[] = {
  60         {
  61                 .type = IIO_MAGN,
  62                 .modified = 1,
  63                 .channel2 = IIO_MOD_X,
  64                 .info_mask = IIO_CHAN_INFO_OFFSET_SHARED_BIT |
  65                 IIO_CHAN_INFO_SCALE_SHARED_BIT |
  66                 IIO_CHAN_INFO_SAMP_FREQ_SHARED_BIT |
  67                 IIO_CHAN_INFO_HYSTERESIS_SHARED_BIT,
  68                 .scan_index = CHANNEL_SCAN_INDEX_X,
  69         }, {
  70                 .type = IIO_MAGN,
  71                 .modified = 1,
  72                 .channel2 = IIO_MOD_Y,
  73                 .info_mask = IIO_CHAN_INFO_OFFSET_SHARED_BIT |
  74                 IIO_CHAN_INFO_SCALE_SHARED_BIT |
  75                 IIO_CHAN_INFO_SAMP_FREQ_SHARED_BIT |
  76                 IIO_CHAN_INFO_HYSTERESIS_SHARED_BIT,
  77                 .scan_index = CHANNEL_SCAN_INDEX_Y,
  78         }, {
  79                 .type = IIO_MAGN,
  80                 .modified = 1,
  81                 .channel2 = IIO_MOD_Z,
  82                 .info_mask = IIO_CHAN_INFO_OFFSET_SHARED_BIT |
  83                 IIO_CHAN_INFO_SCALE_SHARED_BIT |
  84                 IIO_CHAN_INFO_SAMP_FREQ_SHARED_BIT |
  85                 IIO_CHAN_INFO_HYSTERESIS_SHARED_BIT,
  86                 .scan_index = CHANNEL_SCAN_INDEX_Z,
  87         }
  88 };
  89
  90 /* Adjust channel real bits based on report descriptor */
  91 static void magn_3d_adjust_channel_bit_mask(struct iio_chan_spec *channels,
  92                                                 int channel, int size)
  93 {
  94         channels[channel].scan_type.sign = 's';
  95         /* Real storage bits will change based on the report desc. */
  96         channels[channel].scan_type.realbits = size * 8;
  97         /* Maximum size of a sample to capture is u32 */
  98         channels[channel].scan_type.storagebits = sizeof(u32) * 8;
  99 }
 100
 101 /* Channel read_raw handler */
 102 static int magn_3d_read_raw(struct iio_dev *indio_dev,
 103                               struct iio_chan_spec const *chan,
 104                               int *val, int *val2,
 105                               long mask)
 106 {
 107         struct magn_3d_state *magn_state = iio_priv(indio_dev);
 108         int report_id = -1;
 109         u32 address;
 110         int ret;
 111         int ret_type;
 112
 113         *val = 0;
 114         *val2 = 0;
 115         switch (mask) {
 116         case 0:
 117                 report_id =
 118                         magn_state->magn[chan->scan_index].report_id;
 119                 address = magn_3d_addresses[chan->scan_index];
 120                 if (report_id >= 0)
 121                         *val = sensor_hub_input_attr_get_raw_value(
 122                                 magn_state->common_attributes.hsdev,
 123                                 HID_USAGE_SENSOR_COMPASS_3D, address,
 124                                 report_id);
 125                 else {
 126                         *val = 0;
 127                         return -EINVAL;
 128                 }
 129                 ret_type = IIO_VAL_INT;
 130                 break;
 131         case IIO_CHAN_INFO_SCALE:
 132                 *val = magn_state->magn[CHANNEL_SCAN_INDEX_X].units;
 133                 ret_type = IIO_VAL_INT;
 134                 break;
 135         case IIO_CHAN_INFO_OFFSET:
 136                 *val = hid_sensor_convert_exponent(
 137                         magn_state->magn[CHANNEL_SCAN_INDEX_X].unit_expo);
 138                 ret_type = IIO_VAL_INT;
 139                 break;
 140         case IIO_CHAN_INFO_SAMP_FREQ:
 141                 ret = hid_sensor_read_samp_freq_value(
 142                         &magn_state->common_attributes, val, val2);
 143                 ret_type = IIO_VAL_INT_PLUS_MICRO;
 144                 break;
 145         case IIO_CHAN_INFO_HYSTERESIS:
 146                 ret = hid_sensor_read_raw_hyst_value(
 147                         &magn_state->common_attributes, val, val2);
 148                 ret_type = IIO_VAL_INT_PLUS_MICRO;
 149                 break;
 150         default:
 151                 ret_type = -EINVAL;
 152                 break;
 153         }
 154
 155         return ret_type;
 156 }
 157
 158 /* Channel write_raw handler */
 159 static int magn_3d_write_raw(struct iio_dev *indio_dev,
 160                                struct iio_chan_spec const *chan,
 161                                int val,
 162                                int val2,
 163                                long mask)
 164 {
 165         struct magn_3d_state *magn_state = iio_priv(indio_dev);
 166         int ret = 0;
 167
 168         switch (mask) {
 169         case IIO_CHAN_INFO_SAMP_FREQ:
 170                 ret = hid_sensor_write_samp_freq_value(
 171                                 &magn_state->common_attributes, val, val2);
 172                 break;
 173         case IIO_CHAN_INFO_HYSTERESIS:
 174                 ret = hid_sensor_write_raw_hyst_value(
 175                                 &magn_state->common_attributes, val, val2);
 176                 break;
 177         default:
 178                 ret = -EINVAL;
 179         }
 180
 181         return ret;
 182 }
 183
 184 static int magn_3d_write_raw_get_fmt(struct iio_dev *indio_dev,
 185                                struct iio_chan_spec const *chan,
 186                                long mask)
 187 {
 188         return IIO_VAL_INT_PLUS_MICRO;
 189 }
 190
 191 static const struct iio_info magn_3d_info = {
 192         .driver_module = THIS_MODULE,
 193         .read_raw = &magn_3d_read_raw,
 194         .write_raw = &magn_3d_write_raw,
 195         .write_raw_get_fmt = &magn_3d_write_raw_get_fmt,
 196 };
 197
 198 /* Function to push data to buffer */
 199 static void hid_sensor_push_data(struct iio_dev *indio_dev, u8 *data, int len)
 200 {
 201         struct iio_buffer *buffer = indio_dev->buffer;
 202         int datum_sz;
 203
 204         dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n");
 205         if (!buffer) {
 206                 dev_err(&indio_dev->dev, "Buffer == NULL\n");
 207                 return;
 208         }
 209         datum_sz = buffer->access->get_bytes_per_datum(buffer);
 210         if (len > datum_sz) {
 211                 dev_err(&indio_dev->dev, "Datum size mismatch %d:%d\n", len,
 212                                 datum_sz);
 213                 return;
 214         }
 215         iio_push_to_buffer(buffer, (u8 *)data);
 216 }
 217
 218 /* Callback handler to send event after all samples are received and captured */
 219 static int magn_3d_proc_event(struct hid_sensor_hub_device *hsdev,
 220                                 unsigned usage_id,
 221                                 void *priv)
 222 {
 223         struct iio_dev *indio_dev = platform_get_drvdata(priv);
 224         struct magn_3d_state *magn_state = iio_priv(indio_dev);
 225
 226         dev_dbg(&indio_dev->dev, "magn_3d_proc_event [%d]\n",
 227                                 magn_state->common_attributes.data_ready);
 228         if (magn_state->common_attributes.data_ready)
 229                 hid_sensor_push_data(indio_dev,
 230                                 (u8 *)magn_state->magn_val,
 231                                 sizeof(magn_state->magn_val));
 232
 233         return 0;
 234 }
 235
 236 /* Capture samples in local storage */
 237 static int magn_3d_capture_sample(struct hid_sensor_hub_device *hsdev,
 238                                 unsigned usage_id,
 239                                 size_t raw_len, char *raw_data,
 240                                 void *priv)
 241 {
 242         struct iio_dev *indio_dev = platform_get_drvdata(priv);
 243         struct magn_3d_state *magn_state = iio_priv(indio_dev);
 244         int offset;
 245         int ret = -EINVAL;
 246
 247         switch (usage_id) {
 248         case HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_X_AXIS:
 249         case HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_Y_AXIS:
 250         case HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_Z_AXIS:
 251                 offset = usage_id - HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_X_AXIS;
 252                 magn_state->magn_val[CHANNEL_SCAN_INDEX_X + offset] =
 253                                                 *(u32 *)raw_data;
 254                 ret = 0;
 255         break;
 256         default:
 257                 break;
 258         }
 259
 260         return ret;
 261 }
 262
 263 /* Parse report which is specific to an usage id*/
 264 static int magn_3d_parse_report(struct platform_device *pdev,
 265                                 struct hid_sensor_hub_device *hsdev,
 266                                 struct iio_chan_spec *channels,
 267                                 unsigned usage_id,
 268                                 struct magn_3d_state *st)
 269 {
 270         int ret;
 271         int i;
 272
 273         for (i = 0; i <= CHANNEL_SCAN_INDEX_Z; ++i) {
 274                 ret = sensor_hub_input_get_attribute_info(hsdev,
 275                                 HID_INPUT_REPORT,
 276                                 usage_id,
 277                                 HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_X_AXIS + i,
 278                                 &st->magn[CHANNEL_SCAN_INDEX_X + i]);
 279                 if (ret < 0)
 280                         break;
 281                 magn_3d_adjust_channel_bit_mask(channels,
 282                                 CHANNEL_SCAN_INDEX_X + i,
 283                                 st->magn[CHANNEL_SCAN_INDEX_X + i].size);
 284         }
 285         dev_dbg(&pdev->dev, "magn_3d %x:%x, %x:%x, %x:%x\n",
 286                         st->magn[0].index,
 287                         st->magn[0].report_id,
 288                         st->magn[1].index, st->magn[1].report_id,
 289                         st->magn[2].index, st->magn[2].report_id);
 290
 291         return ret;
 292 }
 293
 294 /* Function to initialize the processing for usage id */
 295 static int __devinit hid_magn_3d_probe(struct platform_device *pdev)
 296 {
 297         int ret = 0;
 298         static char *name = "magn_3d";
 299         struct iio_dev *indio_dev;
 300         struct magn_3d_state *magn_state;
 301         struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
 302         struct iio_chan_spec *channels;
 303
 304         indio_dev = iio_device_alloc(sizeof(struct magn_3d_state));
 305         if (indio_dev == NULL) {
 306                 ret = -ENOMEM;
 307                 goto error_ret;
 308         }
 309         platform_set_drvdata(pdev, indio_dev);
 310
 311         magn_state = iio_priv(indio_dev);
 312         magn_state->common_attributes.hsdev = hsdev;
 313         magn_state->common_attributes.pdev = pdev;
 314
 315         ret = hid_sensor_parse_common_attributes(hsdev,
 316                                 HID_USAGE_SENSOR_COMPASS_3D,
 317                                 &magn_state->common_attributes);
 318         if (ret) {
 319                 dev_err(&pdev->dev, "failed to setup common attributes\n");
 320                 goto error_free_dev;
 321         }
 322
 323         channels = kmemdup(magn_3d_channels,
 324                                         sizeof(magn_3d_channels),
 325                                         GFP_KERNEL);
 326         if (!channels) {
 327                 dev_err(&pdev->dev, "failed to duplicate channels\n");
 328                 goto error_free_dev;
 329         }
 330
 331         ret = magn_3d_parse_report(pdev, hsdev, channels,
 332                                 HID_USAGE_SENSOR_COMPASS_3D, magn_state);
 333         if (ret) {
 334                 dev_err(&pdev->dev, "failed to setup attributes\n");
 335                 goto error_free_dev_mem;
 336         }
 337
 338         indio_dev->channels = channels;
 339         indio_dev->num_channels = ARRAY_SIZE(magn_3d_channels);
 340         indio_dev->dev.parent = &pdev->dev;
 341         indio_dev->info = &magn_3d_info;
 342         indio_dev->name = name;
 343         indio_dev->modes = INDIO_DIRECT_MODE;
 344
 345         ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
 346                 NULL, NULL);
 347         if (ret) {
 348                 dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
 349                 goto error_free_dev_mem;
 350         }
 351         magn_state->common_attributes.data_ready = false;
 352         ret = hid_sensor_setup_trigger(indio_dev, name,
 353                                         &magn_state->common_attributes);
 354         if (ret < 0) {
 355                 dev_err(&pdev->dev, "trigger setup failed\n");
 356                 goto error_unreg_buffer_funcs;
 357         }
 358
 359         ret = iio_device_register(indio_dev);
 360         if (ret) {
 361                 dev_err(&pdev->dev, "device register failed\n");
 362                 goto error_remove_trigger;
 363         }
 364
 365         magn_state->callbacks.send_event = magn_3d_proc_event;
 366         magn_state->callbacks.capture_sample = magn_3d_capture_sample;
 367         magn_state->callbacks.pdev = pdev;
 368         ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_COMPASS_3D,
 369                                         &magn_state->callbacks);
 370         if (ret < 0) {
 371                 dev_err(&pdev->dev, "callback reg failed\n");
 372                 goto error_iio_unreg;
 373         }
 374
 375         return ret;
 376
 377 error_iio_unreg:
 378         iio_device_unregister(indio_dev);
 379 error_remove_trigger:
 380         hid_sensor_remove_trigger(indio_dev);
 381 error_unreg_buffer_funcs:
 382         iio_triggered_buffer_cleanup(indio_dev);
 383 error_free_dev_mem:
 384         kfree(indio_dev->channels);
 385 error_free_dev:
 386         iio_device_free(indio_dev);
 387 error_ret:
 388         return ret;
 389 }
 390
 391 /* Function to deinitialize the processing for usage id */
 392 static int __devinit hid_magn_3d_remove(struct platform_device *pdev)
 393 {
 394         struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
 395         struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 396
 397         sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_COMPASS_3D);
 398         iio_device_unregister(indio_dev);
 399         hid_sensor_remove_trigger(indio_dev);
 400         iio_triggered_buffer_cleanup(indio_dev);
 401         kfree(indio_dev->channels);
 402         iio_device_free(indio_dev);
 403
 404         return 0;
 405 }
 406
 407 static struct platform_driver hid_magn_3d_platform_driver = {
 408         .driver = {
 409                 .name   = DRIVER_NAME,
 410                 .owner  = THIS_MODULE,
 411         },
 412         .probe          = hid_magn_3d_probe,
 413         .remove         = hid_magn_3d_remove,
 414 };
 415 module_platform_driver(hid_magn_3d_platform_driver);
 416
 417 MODULE_DESCRIPTION("HID Sensor Magnetometer 3D");
 418 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@intel.com>");
 419 MODULE_LICENSE("GPL");