drivers/iio/accel/st_accel_buffer.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * STMicroelectronics accelerometers driver
   4  *
   5  * Copyright 2012-2013 STMicroelectronics Inc.
   6  *
   7  * Denis Ciocca <denis.ciocca@st.com>
   8  */
   9
  10 #include <linux/module.h>
  11 #include <linux/kernel.h>
  12 #include <linux/slab.h>
  13 #include <linux/stat.h>
  14 #include <linux/interrupt.h>
  15 #include <linux/i2c.h>
  16 #include <linux/delay.h>
  17 #include <linux/iio/iio.h>
  18 #include <linux/iio/buffer.h>
  19 #include <linux/iio/trigger_consumer.h>
  20 #include <linux/iio/triggered_buffer.h>
  21
  22 #include <linux/iio/common/st_sensors.h>
  23 #include "st_accel.h"
  24
  25 int st_accel_trig_set_state(struct iio_trigger *trig, bool state)
  26 {
  27         struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
  28
  29         return st_sensors_set_dataready_irq(indio_dev, state);
  30 }
  31
  32 static int st_accel_buffer_preenable(struct iio_dev *indio_dev)
  33 {
  34         return st_sensors_set_enable(indio_dev, true);
  35 }
  36
  37 static int st_accel_buffer_postenable(struct iio_dev *indio_dev)
  38 {
  39         int err;
  40         struct st_sensor_data *adata = iio_priv(indio_dev);
  41
  42         adata->buffer_data = kmalloc(indio_dev->scan_bytes, GFP_KERNEL);
  43         if (adata->buffer_data == NULL) {
  44                 err = -ENOMEM;
  45                 goto allocate_memory_error;
  46         }
  47
  48         err = st_sensors_set_axis_enable(indio_dev,
  49                                         (u8)indio_dev->active_scan_mask[0]);
  50         if (err < 0)
  51                 goto st_accel_buffer_postenable_error;
  52
  53         err = iio_triggered_buffer_postenable(indio_dev);
  54         if (err < 0)
  55                 goto st_accel_buffer_postenable_error;
  56
  57         return err;
  58
  59 st_accel_buffer_postenable_error:
  60         kfree(adata->buffer_data);
  61 allocate_memory_error:
  62         return err;
  63 }
  64
  65 static int st_accel_buffer_predisable(struct iio_dev *indio_dev)
  66 {
  67         int err;
  68         struct st_sensor_data *adata = iio_priv(indio_dev);
  69
  70         err = iio_triggered_buffer_predisable(indio_dev);
  71         if (err < 0)
  72                 goto st_accel_buffer_predisable_error;
  73
  74         err = st_sensors_set_axis_enable(indio_dev, ST_SENSORS_ENABLE_ALL_AXIS);
  75         if (err < 0)
  76                 goto st_accel_buffer_predisable_error;
  77
  78         err = st_sensors_set_enable(indio_dev, false);
  79
  80 st_accel_buffer_predisable_error:
  81         kfree(adata->buffer_data);
  82         return err;
  83 }
  84
  85 static const struct iio_buffer_setup_ops st_accel_buffer_setup_ops = {
  86         .preenable = &st_accel_buffer_preenable,
  87         .postenable = &st_accel_buffer_postenable,
  88         .predisable = &st_accel_buffer_predisable,
  89 };
  90
  91 int st_accel_allocate_ring(struct iio_dev *indio_dev)
  92 {
  93         return iio_triggered_buffer_setup(indio_dev, NULL,
  94                 &st_sensors_trigger_handler, &st_accel_buffer_setup_ops);
  95 }
  96
  97 void st_accel_deallocate_ring(struct iio_dev *indio_dev)
  98 {
  99         iio_triggered_buffer_cleanup(indio_dev);
 100 }
 101
 102 MODULE_AUTHOR("Denis Ciocca <denis.ciocca@st.com>");
 103 MODULE_DESCRIPTION("STMicroelectronics accelerometers buffer");
 104 MODULE_LICENSE("GPL v2");