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