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/buffer.h>
  18 #include <linux/iio/kfifo_buf.h>
  19 #include <linux/module.h>
  20 #include <linux/slab.h>
  21 #include "ssp_iio_sensor.h"
  22
  23 /**
  24  * ssp_common_buffer_postenable() - generic postenable callback for ssp buffer
  25  *
  26  * @indio_dev:          iio device
  27  *
  28  * Returns 0 or negative value in case of error
  29  */
  30 int ssp_common_buffer_postenable(struct iio_dev *indio_dev)
  31 {
  32         struct ssp_sensor_data *spd = iio_priv(indio_dev);
  33         struct ssp_data *data = dev_get_drvdata(indio_dev->dev.parent->parent);
  34
  35         /* the allocation is made in post because scan size is known in this
  36          * moment
  37          * */
  38         spd->buffer = kmalloc(indio_dev->scan_bytes, GFP_KERNEL | GFP_DMA);
  39         if (!spd->buffer)
  40                 return -ENOMEM;
  41
  42         return ssp_enable_sensor(data, spd->type,
  43                                  ssp_get_sensor_delay(data, spd->type));
  44 }
  45 EXPORT_SYMBOL(ssp_common_buffer_postenable);
  46
  47 /**
  48  * ssp_common_buffer_postdisable() - generic postdisable callback for ssp buffer
  49  *
  50  * @indio_dev:          iio device
  51  *
  52  * Returns 0 or negative value in case of error
  53  */
  54 int ssp_common_buffer_postdisable(struct iio_dev *indio_dev)
  55 {
  56         int ret;
  57         struct ssp_sensor_data *spd = iio_priv(indio_dev);
  58         struct ssp_data *data = dev_get_drvdata(indio_dev->dev.parent->parent);
  59
  60         ret = ssp_disable_sensor(data, spd->type);
  61         if (ret < 0)
  62                 return ret;
  63
  64         kfree(spd->buffer);
  65
  66         return ret;
  67 }
  68 EXPORT_SYMBOL(ssp_common_buffer_postdisable);
  69
  70 /**
  71  * ssp_common_process_data() - Common process data callback for ssp sensors
  72  *
  73  * @indio_dev:          iio device
  74  * @buf:                source buffer
  75  * @len:                sensor data length
  76  * @timestamp:          system timestamp
  77  *
  78  * Returns 0 or negative value in case of error
  79  */
  80 int ssp_common_process_data(struct iio_dev *indio_dev, void *buf,
  81                             unsigned int len, int64_t timestamp)
  82 {
  83         __le32 time;
  84         int64_t calculated_time;
  85         struct ssp_sensor_data *spd = iio_priv(indio_dev);
  86
  87         if (indio_dev->scan_bytes == 0)
  88                 return 0;
  89
  90         /*
  91          * it always sends full set of samples, remember about available masks
  92          */
  93         memcpy(spd->buffer, buf, len);
  94
  95         if (indio_dev->scan_timestamp) {
  96                 memcpy(&time, &((char *)buf)[len], SSP_TIME_SIZE);
  97                 calculated_time =
  98                         timestamp + (int64_t)le32_to_cpu(time) * 1000000;
  99         }
 100
 101         return iio_push_to_buffers_with_timestamp(indio_dev, spd->buffer,
 102                                                   calculated_time);
 103 }
 104 EXPORT_SYMBOL(ssp_common_process_data);
 105
 106 MODULE_AUTHOR("Karol Wrona <k.wrona@samsung.com>");
 107 MODULE_DESCRIPTION("Samsung sensorhub commons");
 108 MODULE_LICENSE("GPL");