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