drivers/iio/light/hid-sensor-als.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-trigger.h"
  32
  33 /*Format: HID-SENSOR-usage_id_in_hex*/
  34 /*Usage ID from spec for Accelerometer-3D: 0x200041*/
  35 #define DRIVER_NAME "HID-SENSOR-200041"
  36
  37 #define CHANNEL_SCAN_INDEX_ILLUM 0
  38
  39 struct als_state {
  40         struct hid_sensor_hub_callbacks callbacks;
  41         struct hid_sensor_common common_attributes;
  42         struct hid_sensor_hub_attribute_info als_illum;
  43         u32 illum;
  44 };
  45
  46 /* Channel definitions */
  47 static const struct iio_chan_spec als_channels[] = {
  48         {
  49                 .type = IIO_INTENSITY,
  50                 .modified = 1,
  51                 .channel2 = IIO_MOD_LIGHT_BOTH,
  52                 .info_mask = IIO_CHAN_INFO_OFFSET_SHARED_BIT |
  53                 IIO_CHAN_INFO_SCALE_SHARED_BIT |
  54                 IIO_CHAN_INFO_SAMP_FREQ_SHARED_BIT |
  55                 IIO_CHAN_INFO_HYSTERESIS_SHARED_BIT,
  56                 .scan_index = CHANNEL_SCAN_INDEX_ILLUM,
  57         }
  58 };
  59
  60 /* Adjust channel real bits based on report descriptor */
  61 static void als_adjust_channel_bit_mask(struct iio_chan_spec *channels,
  62                                         int channel, int size)
  63 {
  64         channels[channel].scan_type.sign = 's';
  65         /* Real storage bits will change based on the report desc. */
  66         channels[channel].scan_type.realbits = size * 8;
  67         /* Maximum size of a sample to capture is u32 */
  68         channels[channel].scan_type.storagebits = sizeof(u32) * 8;
  69 }
  70
  71 /* Channel read_raw handler */
  72 static int als_read_raw(struct iio_dev *indio_dev,
  73                               struct iio_chan_spec const *chan,
  74                               int *val, int *val2,
  75                               long mask)
  76 {
  77         struct als_state *als_state = iio_priv(indio_dev);
  78         int report_id = -1;
  79         u32 address;
  80         int ret;
  81         int ret_type;
  82
  83         *val = 0;
  84         *val2 = 0;
  85         switch (mask) {
  86         case 0:
  87                 switch (chan->scan_index) {
  88                 case  CHANNEL_SCAN_INDEX_ILLUM:
  89                         report_id = als_state->als_illum.report_id;
  90                         address =
  91                         HID_USAGE_SENSOR_LIGHT_ILLUM;
  92                         break;
  93                 default:
  94                         report_id = -1;
  95                         break;
  96                 }
  97                 if (report_id >= 0)
  98                         *val = sensor_hub_input_attr_get_raw_value(
  99                                 als_state->common_attributes.hsdev,
 100                                 HID_USAGE_SENSOR_ALS, address,
 101                                 report_id);
 102                 else {
 103                         *val = 0;
 104                         return -EINVAL;
 105                 }
 106                 ret_type = IIO_VAL_INT;
 107                 break;
 108         case IIO_CHAN_INFO_SCALE:
 109                 *val = als_state->als_illum.units;
 110                 ret_type = IIO_VAL_INT;
 111                 break;
 112         case IIO_CHAN_INFO_OFFSET:
 113                 *val = hid_sensor_convert_exponent(
 114                                 als_state->als_illum.unit_expo);
 115                 ret_type = IIO_VAL_INT;
 116                 break;
 117         case IIO_CHAN_INFO_SAMP_FREQ:
 118                 ret = hid_sensor_read_samp_freq_value(
 119                                 &als_state->common_attributes, val, val2);
 120                 ret_type = IIO_VAL_INT_PLUS_MICRO;
 121                 break;
 122         case IIO_CHAN_INFO_HYSTERESIS:
 123                 ret = hid_sensor_read_raw_hyst_value(
 124                                 &als_state->common_attributes, val, val2);
 125                 ret_type = IIO_VAL_INT_PLUS_MICRO;
 126                 break;
 127         default:
 128                 ret_type = -EINVAL;
 129                 break;
 130         }
 131
 132         return ret_type;
 133 }
 134
 135 /* Channel write_raw handler */
 136 static int als_write_raw(struct iio_dev *indio_dev,
 137                                struct iio_chan_spec const *chan,
 138                                int val,
 139                                int val2,
 140                                long mask)
 141 {
 142         struct als_state *als_state = iio_priv(indio_dev);
 143         int ret = 0;
 144
 145         switch (mask) {
 146         case IIO_CHAN_INFO_SAMP_FREQ:
 147                 ret = hid_sensor_write_samp_freq_value(
 148                                 &als_state->common_attributes, val, val2);
 149                 break;
 150         case IIO_CHAN_INFO_HYSTERESIS:
 151                 ret = hid_sensor_write_raw_hyst_value(
 152                                 &als_state->common_attributes, val, val2);
 153                 break;
 154         default:
 155                 ret = -EINVAL;
 156         }
 157
 158         return ret;
 159 }
 160
 161 static int als_write_raw_get_fmt(struct iio_dev *indio_dev,
 162                                struct iio_chan_spec const *chan,
 163                                long mask)
 164 {
 165         return IIO_VAL_INT_PLUS_MICRO;
 166 }
 167
 168 static const struct iio_info als_info = {
 169         .driver_module = THIS_MODULE,
 170         .read_raw = &als_read_raw,
 171         .write_raw = &als_write_raw,
 172         .write_raw_get_fmt = &als_write_raw_get_fmt,
 173 };
 174
 175 /* Function to push data to buffer */
 176 static void hid_sensor_push_data(struct iio_dev *indio_dev, u8 *data, int len)
 177 {
 178         dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n");
 179         iio_push_to_buffers(indio_dev, (u8 *)data);
 180 }
 181
 182 /* Callback handler to send event after all samples are received and captured */
 183 static int als_proc_event(struct hid_sensor_hub_device *hsdev,
 184                                 unsigned usage_id,
 185                                 void *priv)
 186 {
 187         struct iio_dev *indio_dev = platform_get_drvdata(priv);
 188         struct als_state *als_state = iio_priv(indio_dev);
 189
 190         dev_dbg(&indio_dev->dev, "als_proc_event [%d]\n",
 191                                 als_state->common_attributes.data_ready);
 192         if (als_state->common_attributes.data_ready)
 193                 hid_sensor_push_data(indio_dev,
 194                                 (u8 *)&als_state->illum,
 195                                 sizeof(als_state->illum));
 196
 197         return 0;
 198 }
 199
 200 /* Capture samples in local storage */
 201 static int als_capture_sample(struct hid_sensor_hub_device *hsdev,
 202                                 unsigned usage_id,
 203                                 size_t raw_len, char *raw_data,
 204                                 void *priv)
 205 {
 206         struct iio_dev *indio_dev = platform_get_drvdata(priv);
 207         struct als_state *als_state = iio_priv(indio_dev);
 208         int ret = -EINVAL;
 209
 210         switch (usage_id) {
 211         case HID_USAGE_SENSOR_LIGHT_ILLUM:
 212                 als_state->illum = *(u32 *)raw_data;
 213                 ret = 0;
 214                 break;
 215         default:
 216                 break;
 217         }
 218
 219         return ret;
 220 }
 221
 222 /* Parse report which is specific to an usage id*/
 223 static int als_parse_report(struct platform_device *pdev,
 224                                 struct hid_sensor_hub_device *hsdev,
 225                                 struct iio_chan_spec *channels,
 226                                 unsigned usage_id,
 227                                 struct als_state *st)
 228 {
 229         int ret;
 230
 231         ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
 232                         usage_id,
 233                         HID_USAGE_SENSOR_LIGHT_ILLUM,
 234                         &st->als_illum);
 235         if (ret < 0)
 236                 return ret;
 237         als_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_ILLUM,
 238                                         st->als_illum.size);
 239
 240         dev_dbg(&pdev->dev, "als %x:%x\n", st->als_illum.index,
 241                         st->als_illum.report_id);
 242
 243         return ret;
 244 }
 245
 246 /* Function to initialize the processing for usage id */
 247 static int hid_als_probe(struct platform_device *pdev)
 248 {
 249         int ret = 0;
 250         static const char *name = "als";
 251         struct iio_dev *indio_dev;
 252         struct als_state *als_state;
 253         struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
 254         struct iio_chan_spec *channels;
 255
 256         indio_dev = iio_device_alloc(sizeof(struct als_state));
 257         if (indio_dev == NULL) {
 258                 ret = -ENOMEM;
 259                 goto error_ret;
 260         }
 261         platform_set_drvdata(pdev, indio_dev);
 262
 263         als_state = iio_priv(indio_dev);
 264         als_state->common_attributes.hsdev = hsdev;
 265         als_state->common_attributes.pdev = pdev;
 266
 267         ret = hid_sensor_parse_common_attributes(hsdev, HID_USAGE_SENSOR_ALS,
 268                                         &als_state->common_attributes);
 269         if (ret) {
 270                 dev_err(&pdev->dev, "failed to setup common attributes\n");
 271                 goto error_free_dev;
 272         }
 273
 274         channels = kmemdup(als_channels, sizeof(als_channels), GFP_KERNEL);
 275         if (!channels) {
 276                 ret = -ENOMEM;
 277                 dev_err(&pdev->dev, "failed to duplicate channels\n");
 278                 goto error_free_dev;
 279         }
 280
 281         ret = als_parse_report(pdev, hsdev, channels,
 282                                 HID_USAGE_SENSOR_ALS, als_state);
 283         if (ret) {
 284                 dev_err(&pdev->dev, "failed to setup attributes\n");
 285                 goto error_free_dev_mem;
 286         }
 287
 288         indio_dev->channels = channels;
 289         indio_dev->num_channels =
 290                                 ARRAY_SIZE(als_channels);
 291         indio_dev->dev.parent = &pdev->dev;
 292         indio_dev->info = &als_info;
 293         indio_dev->name = name;
 294         indio_dev->modes = INDIO_DIRECT_MODE;
 295
 296         ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
 297                 NULL, NULL);
 298         if (ret) {
 299                 dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
 300                 goto error_free_dev_mem;
 301         }
 302         als_state->common_attributes.data_ready = false;
 303         ret = hid_sensor_setup_trigger(indio_dev, name,
 304                                 &als_state->common_attributes);
 305         if (ret < 0) {
 306                 dev_err(&pdev->dev, "trigger setup failed\n");
 307                 goto error_unreg_buffer_funcs;
 308         }
 309
 310         ret = iio_device_register(indio_dev);
 311         if (ret) {
 312                 dev_err(&pdev->dev, "device register failed\n");
 313                 goto error_remove_trigger;
 314         }
 315
 316         als_state->callbacks.send_event = als_proc_event;
 317         als_state->callbacks.capture_sample = als_capture_sample;
 318         als_state->callbacks.pdev = pdev;
 319         ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_ALS,
 320                                         &als_state->callbacks);
 321         if (ret < 0) {
 322                 dev_err(&pdev->dev, "callback reg failed\n");
 323                 goto error_iio_unreg;
 324         }
 325
 326         return ret;
 327
 328 error_iio_unreg:
 329         iio_device_unregister(indio_dev);
 330 error_remove_trigger:
 331         hid_sensor_remove_trigger(indio_dev);
 332 error_unreg_buffer_funcs:
 333         iio_triggered_buffer_cleanup(indio_dev);
 334 error_free_dev_mem:
 335         kfree(indio_dev->channels);
 336 error_free_dev:
 337         iio_device_free(indio_dev);
 338 error_ret:
 339         return ret;
 340 }
 341
 342 /* Function to deinitialize the processing for usage id */
 343 static int hid_als_remove(struct platform_device *pdev)
 344 {
 345         struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
 346         struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 347
 348         sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_ALS);
 349         iio_device_unregister(indio_dev);
 350         hid_sensor_remove_trigger(indio_dev);
 351         iio_triggered_buffer_cleanup(indio_dev);
 352         kfree(indio_dev->channels);
 353         iio_device_free(indio_dev);
 354
 355         return 0;
 356 }
 357
 358 static struct platform_driver hid_als_platform_driver = {
 359         .driver = {
 360                 .name   = DRIVER_NAME,
 361                 .owner  = THIS_MODULE,
 362         },
 363         .probe          = hid_als_probe,
 364         .remove         = hid_als_remove,
 365 };
 366 module_platform_driver(hid_als_platform_driver);
 367
 368 MODULE_DESCRIPTION("HID Sensor ALS");
 369 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@intel.com>");
 370 MODULE_LICENSE("GPL");