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/delay.h>
  26 #include <linux/hid-sensor-hub.h>
  27 #include <linux/iio/iio.h>
  28 #include <linux/iio/sysfs.h>
  29 #include <linux/iio/buffer.h>
  30 #include <linux/iio/trigger_consumer.h>
  31 #include <linux/iio/triggered_buffer.h>
  32 #include "../common/hid-sensors/hid-sensor-trigger.h"
  33
  34 #define CHANNEL_SCAN_INDEX_ILLUM 0
  35
  36 struct als_state {
  37         struct hid_sensor_hub_callbacks callbacks;
  38         struct hid_sensor_common common_attributes;
  39         struct hid_sensor_hub_attribute_info als_illum;
  40         u32 illum;
  41         int scale_pre_decml;
  42         int scale_post_decml;
  43         int scale_precision;
  44         int value_offset;
  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_separate = BIT(IIO_CHAN_INFO_RAW),
  54                 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
  55                 BIT(IIO_CHAN_INFO_SCALE) |
  56                 BIT(IIO_CHAN_INFO_SAMP_FREQ) |
  57                 BIT(IIO_CHAN_INFO_HYSTERESIS),
  58                 .scan_index = CHANNEL_SCAN_INDEX_ILLUM,
  59         }
  60 };
  61
  62 /* Adjust channel real bits based on report descriptor */
  63 static void als_adjust_channel_bit_mask(struct iio_chan_spec *channels,
  64                                         int channel, int size)
  65 {
  66         channels[channel].scan_type.sign = 's';
  67         /* Real storage bits will change based on the report desc. */
  68         channels[channel].scan_type.realbits = size * 8;
  69         /* Maximum size of a sample to capture is u32 */
  70         channels[channel].scan_type.storagebits = sizeof(u32) * 8;
  71 }
  72
  73 /* Channel read_raw handler */
  74 static int als_read_raw(struct iio_dev *indio_dev,
  75                               struct iio_chan_spec const *chan,
  76                               int *val, int *val2,
  77                               long mask)
  78 {
  79         struct als_state *als_state = iio_priv(indio_dev);
  80         int report_id = -1;
  81         u32 address;
  82         int ret_type;
  83         s32 poll_value;
  84
  85         *val = 0;
  86         *val2 = 0;
  87         switch (mask) {
  88         case 0:
  89                 switch (chan->scan_index) {
  90                 case  CHANNEL_SCAN_INDEX_ILLUM:
  91                         report_id = als_state->als_illum.report_id;
  92                         address =
  93                         HID_USAGE_SENSOR_LIGHT_ILLUM;
  94                         break;
  95                 default:
  96                         report_id = -1;
  97                         break;
  98                 }
  99                 if (report_id >= 0) {
 100                         poll_value = hid_sensor_read_poll_value(
 101                                                 &als_state->common_attributes);
 102                         if (poll_value < 0)
 103                                 return -EINVAL;
 104
 105                         hid_sensor_power_state(&als_state->common_attributes,
 106                                                 true);
 107                         msleep_interruptible(poll_value * 2);
 108
 109                         *val = sensor_hub_input_attr_get_raw_value(
 110                                         als_state->common_attributes.hsdev,
 111                                         HID_USAGE_SENSOR_ALS, address,
 112                                         report_id,
 113                                         SENSOR_HUB_SYNC);
 114                         hid_sensor_power_state(&als_state->common_attributes,
 115                                                 false);
 116                 } else {
 117                         *val = 0;
 118                         return -EINVAL;
 119                 }
 120                 ret_type = IIO_VAL_INT;
 121                 break;
 122         case IIO_CHAN_INFO_SCALE:
 123                 *val = als_state->scale_pre_decml;
 124                 *val2 = als_state->scale_post_decml;
 125                 ret_type = als_state->scale_precision;
 126                 break;
 127         case IIO_CHAN_INFO_OFFSET:
 128                 *val = als_state->value_offset;
 129                 ret_type = IIO_VAL_INT;
 130                 break;
 131         case IIO_CHAN_INFO_SAMP_FREQ:
 132                 ret_type = hid_sensor_read_samp_freq_value(
 133                                 &als_state->common_attributes, val, val2);
 134                 break;
 135         case IIO_CHAN_INFO_HYSTERESIS:
 136                 ret_type = hid_sensor_read_raw_hyst_value(
 137                                 &als_state->common_attributes, val, val2);
 138                 break;
 139         default:
 140                 ret_type = -EINVAL;
 141                 break;
 142         }
 143
 144         return ret_type;
 145 }
 146
 147 /* Channel write_raw handler */
 148 static int als_write_raw(struct iio_dev *indio_dev,
 149                                struct iio_chan_spec const *chan,
 150                                int val,
 151                                int val2,
 152                                long mask)
 153 {
 154         struct als_state *als_state = iio_priv(indio_dev);
 155         int ret = 0;
 156
 157         switch (mask) {
 158         case IIO_CHAN_INFO_SAMP_FREQ:
 159                 ret = hid_sensor_write_samp_freq_value(
 160                                 &als_state->common_attributes, val, val2);
 161                 break;
 162         case IIO_CHAN_INFO_HYSTERESIS:
 163                 ret = hid_sensor_write_raw_hyst_value(
 164                                 &als_state->common_attributes, val, val2);
 165                 break;
 166         default:
 167                 ret = -EINVAL;
 168         }
 169
 170         return ret;
 171 }
 172
 173 static const struct iio_info als_info = {
 174         .driver_module = THIS_MODULE,
 175         .read_raw = &als_read_raw,
 176         .write_raw = &als_write_raw,
 177 };
 178
 179 /* Function to push data to buffer */
 180 static void hid_sensor_push_data(struct iio_dev *indio_dev, const void *data,
 181                                         int len)
 182 {
 183         dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n");
 184         iio_push_to_buffers(indio_dev, data);
 185 }
 186
 187 /* Callback handler to send event after all samples are received and captured */
 188 static int als_proc_event(struct hid_sensor_hub_device *hsdev,
 189                                 unsigned usage_id,
 190                                 void *priv)
 191 {
 192         struct iio_dev *indio_dev = platform_get_drvdata(priv);
 193         struct als_state *als_state = iio_priv(indio_dev);
 194
 195         dev_dbg(&indio_dev->dev, "als_proc_event\n");
 196         if (atomic_read(&als_state->common_attributes.data_ready))
 197                 hid_sensor_push_data(indio_dev,
 198                                 &als_state->illum,
 199                                 sizeof(als_state->illum));
 200
 201         return 0;
 202 }
 203
 204 /* Capture samples in local storage */
 205 static int als_capture_sample(struct hid_sensor_hub_device *hsdev,
 206                                 unsigned usage_id,
 207                                 size_t raw_len, char *raw_data,
 208                                 void *priv)
 209 {
 210         struct iio_dev *indio_dev = platform_get_drvdata(priv);
 211         struct als_state *als_state = iio_priv(indio_dev);
 212         int ret = -EINVAL;
 213
 214         switch (usage_id) {
 215         case HID_USAGE_SENSOR_LIGHT_ILLUM:
 216                 als_state->illum = *(u32 *)raw_data;
 217                 ret = 0;
 218                 break;
 219         default:
 220                 break;
 221         }
 222
 223         return ret;
 224 }
 225
 226 /* Parse report which is specific to an usage id*/
 227 static int als_parse_report(struct platform_device *pdev,
 228                                 struct hid_sensor_hub_device *hsdev,
 229                                 struct iio_chan_spec *channels,
 230                                 unsigned usage_id,
 231                                 struct als_state *st)
 232 {
 233         int ret;
 234
 235         ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
 236                         usage_id,
 237                         HID_USAGE_SENSOR_LIGHT_ILLUM,
 238                         &st->als_illum);
 239         if (ret < 0)
 240                 return ret;
 241         als_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_ILLUM,
 242                                         st->als_illum.size);
 243
 244         dev_dbg(&pdev->dev, "als %x:%x\n", st->als_illum.index,
 245                         st->als_illum.report_id);
 246
 247         st->scale_precision = hid_sensor_format_scale(
 248                                 HID_USAGE_SENSOR_ALS,
 249                                 &st->als_illum,
 250                                 &st->scale_pre_decml, &st->scale_post_decml);
 251
 252         /* Set Sensitivity field ids, when there is no individual modifier */
 253         if (st->common_attributes.sensitivity.index < 0) {
 254                 sensor_hub_input_get_attribute_info(hsdev,
 255                         HID_FEATURE_REPORT, usage_id,
 256                         HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS |
 257                         HID_USAGE_SENSOR_DATA_LIGHT,
 258                         &st->common_attributes.sensitivity);
 259                 dev_dbg(&pdev->dev, "Sensitivity index:report %d:%d\n",
 260                         st->common_attributes.sensitivity.index,
 261                         st->common_attributes.sensitivity.report_id);
 262         }
 263         return ret;
 264 }
 265
 266 /* Function to initialize the processing for usage id */
 267 static int hid_als_probe(struct platform_device *pdev)
 268 {
 269         int ret = 0;
 270         static const char *name = "als";
 271         struct iio_dev *indio_dev;
 272         struct als_state *als_state;
 273         struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
 274         struct iio_chan_spec *channels;
 275
 276         indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(struct als_state));
 277         if (!indio_dev)
 278                 return -ENOMEM;
 279         platform_set_drvdata(pdev, indio_dev);
 280
 281         als_state = iio_priv(indio_dev);
 282         als_state->common_attributes.hsdev = hsdev;
 283         als_state->common_attributes.pdev = pdev;
 284
 285         ret = hid_sensor_parse_common_attributes(hsdev, HID_USAGE_SENSOR_ALS,
 286                                         &als_state->common_attributes);
 287         if (ret) {
 288                 dev_err(&pdev->dev, "failed to setup common attributes\n");
 289                 return ret;
 290         }
 291
 292         channels = kmemdup(als_channels, sizeof(als_channels), GFP_KERNEL);
 293         if (!channels) {
 294                 dev_err(&pdev->dev, "failed to duplicate channels\n");
 295                 return -ENOMEM;
 296         }
 297
 298         ret = als_parse_report(pdev, hsdev, channels,
 299                                 HID_USAGE_SENSOR_ALS, als_state);
 300         if (ret) {
 301                 dev_err(&pdev->dev, "failed to setup attributes\n");
 302                 goto error_free_dev_mem;
 303         }
 304
 305         indio_dev->channels = channels;
 306         indio_dev->num_channels =
 307                                 ARRAY_SIZE(als_channels);
 308         indio_dev->dev.parent = &pdev->dev;
 309         indio_dev->info = &als_info;
 310         indio_dev->name = name;
 311         indio_dev->modes = INDIO_DIRECT_MODE;
 312
 313         ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
 314                 NULL, NULL);
 315         if (ret) {
 316                 dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
 317                 goto error_free_dev_mem;
 318         }
 319         atomic_set(&als_state->common_attributes.data_ready, 0);
 320         ret = hid_sensor_setup_trigger(indio_dev, name,
 321                                 &als_state->common_attributes);
 322         if (ret < 0) {
 323                 dev_err(&pdev->dev, "trigger setup failed\n");
 324                 goto error_unreg_buffer_funcs;
 325         }
 326
 327         ret = iio_device_register(indio_dev);
 328         if (ret) {
 329                 dev_err(&pdev->dev, "device register failed\n");
 330                 goto error_remove_trigger;
 331         }
 332
 333         als_state->callbacks.send_event = als_proc_event;
 334         als_state->callbacks.capture_sample = als_capture_sample;
 335         als_state->callbacks.pdev = pdev;
 336         ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_ALS,
 337                                         &als_state->callbacks);
 338         if (ret < 0) {
 339                 dev_err(&pdev->dev, "callback reg failed\n");
 340                 goto error_iio_unreg;
 341         }
 342
 343         return ret;
 344
 345 error_iio_unreg:
 346         iio_device_unregister(indio_dev);
 347 error_remove_trigger:
 348         hid_sensor_remove_trigger(&als_state->common_attributes);
 349 error_unreg_buffer_funcs:
 350         iio_triggered_buffer_cleanup(indio_dev);
 351 error_free_dev_mem:
 352         kfree(indio_dev->channels);
 353         return ret;
 354 }
 355
 356 /* Function to deinitialize the processing for usage id */
 357 static int hid_als_remove(struct platform_device *pdev)
 358 {
 359         struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
 360         struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 361         struct als_state *als_state = iio_priv(indio_dev);
 362
 363         sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_ALS);
 364         iio_device_unregister(indio_dev);
 365         hid_sensor_remove_trigger(&als_state->common_attributes);
 366         iio_triggered_buffer_cleanup(indio_dev);
 367         kfree(indio_dev->channels);
 368
 369         return 0;
 370 }
 371
 372 static struct platform_device_id hid_als_ids[] = {
 373         {
 374                 /* Format: HID-SENSOR-usage_id_in_hex_lowercase */
 375                 .name = "HID-SENSOR-200041",
 376         },
 377         { /* sentinel */ }
 378 };
 379 MODULE_DEVICE_TABLE(platform, hid_als_ids);
 380
 381 static struct platform_driver hid_als_platform_driver = {
 382         .id_table = hid_als_ids,
 383         .driver = {
 384                 .name   = KBUILD_MODNAME,
 385         },
 386         .probe          = hid_als_probe,
 387         .remove         = hid_als_remove,
 388 };
 389 module_platform_driver(hid_als_platform_driver);
 390
 391 MODULE_DESCRIPTION("HID Sensor ALS");
 392 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@intel.com>");
 393 MODULE_LICENSE("GPL");