drivers/iio/common/ssp_sensors/ssp_iio.c

   1 /*
   2  *  Copyright (C) 2014, Samsung Electronics Co. Ltd. All Rights Reserved.
   3  *
   4  *  This program is free software; you can redistribute it and/or modify
   5  *  it under the terms of the GNU General Public License as published by
   6  *  the Free Software Foundation; either version 2 of the License, or
   7  *  (at your option) any later version.
   8  *
   9  *  This program is distributed in the hope that it will be useful,
  10  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  *  GNU General Public License for more details.
  13  *
  14  */
  15
  16 #include <linux/iio/common/ssp_sensors.h>
  17 #include <linux/iio/kfifo_buf.h>
  18 #include <linux/module.h>
  19 #include <linux/slab.h>
  20 #include "ssp_iio_sensor.h"
  21
  22 /**
  23  * ssp_common_buffer_postenable() - generic postenable callback for ssp buffer
  24  *
  25  * @indio_dev:          iio device
  26  *
  27  * Returns 0 or negative value in case of error
  28  */
  29 int ssp_common_buffer_postenable(struct iio_dev *indio_dev)
  30 {
  31         struct ssp_sensor_data *spd = iio_priv(indio_dev);
  32         struct ssp_data *data = dev_get_drvdata(indio_dev->dev.parent->parent);
  33
  34         /* the allocation is made in post because scan size is known in this
  35          * moment
  36          * */
  37         spd->buffer = kmalloc(indio_dev->scan_bytes, GFP_KERNEL | GFP_DMA);
  38         if (!spd->buffer)
  39                 return -ENOMEM;
  40
  41         return ssp_enable_sensor(data, spd->type,
  42                                  ssp_get_sensor_delay(data, spd->type));
  43 }
  44 EXPORT_SYMBOL(ssp_common_buffer_postenable);
  45
  46 /**
  47  * ssp_common_buffer_postdisable() - generic postdisable callback for ssp buffer
  48  *
  49  * @indio_dev:          iio device
  50  *
  51  * Returns 0 or negative value in case of error
  52  */
  53 int ssp_common_buffer_postdisable(struct iio_dev *indio_dev)
  54 {
  55         int ret;
  56         struct ssp_sensor_data *spd = iio_priv(indio_dev);
  57         struct ssp_data *data = dev_get_drvdata(indio_dev->dev.parent->parent);
  58
  59         ret = ssp_disable_sensor(data, spd->type);
  60         if (ret < 0)
  61                 return ret;
  62
  63         kfree(spd->buffer);
  64
  65         return ret;
  66 }
  67 EXPORT_SYMBOL(ssp_common_buffer_postdisable);
  68
  69 /**
  70  * ssp_common_process_data() - Common process data callback for ssp sensors
  71  *
  72  * @indio_dev:          iio device
  73  * @buf:                source buffer
  74  * @len:                sensor data length
  75  * @timestamp:          system timestamp
  76  *
  77  * Returns 0 or negative value in case of error
  78  */
  79 int ssp_common_process_data(struct iio_dev *indio_dev, void *buf,
  80                             unsigned int len, int64_t timestamp)
  81 {
  82         __le32 time;
  83         int64_t calculated_time;
  84         struct ssp_sensor_data *spd = iio_priv(indio_dev);
  85
  86         if (indio_dev->scan_bytes == 0)
  87                 return 0;
  88
  89         /*
  90          * it always sends full set of samples, remember about available masks
  91          */
  92         memcpy(spd->buffer, buf, len);
  93
  94         if (indio_dev->scan_timestamp) {
  95                 memcpy(&time, &((char *)buf)[len], SSP_TIME_SIZE);
  96                 calculated_time =
  97                         timestamp + (int64_t)le32_to_cpu(time) * 1000000;
  98         }
  99
 100         return iio_push_to_buffers_with_timestamp(indio_dev, spd->buffer,
 101                                                   calculated_time);
 102 }
 103 EXPORT_SYMBOL(ssp_common_process_data);
 104
 105 MODULE_AUTHOR("Karol Wrona <k.wrona@samsung.com>");
 106 MODULE_DESCRIPTION("Samsung sensorhub commons");
 107 MODULE_LICENSE("GPL");