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