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