diff options
Diffstat (limited to 'drivers/staging/comedi/comedi_fops.c')
| -rw-r--r-- | drivers/staging/comedi/comedi_fops.c | 16 |
1 files changed, 7 insertions, 9 deletions
diff --git a/drivers/staging/comedi/comedi_fops.c b/drivers/staging/comedi/comedi_fops.c index d569484f315b..8cb9d956e8f2 100644 --- a/drivers/staging/comedi/comedi_fops.c +++ b/drivers/staging/comedi/comedi_fops.c @@ -177,7 +177,7 @@ static void comedi_free_board_dev(struct comedi_device *dev) } static struct comedi_subdevice -*comedi_subdevice_from_minor(unsigned minor) +*comedi_subdevice_from_minor(const struct comedi_device *dev, unsigned minor) { struct comedi_subdevice *s; unsigned int i = minor - COMEDI_NUM_BOARD_MINORS; @@ -185,6 +185,8 @@ static struct comedi_subdevice BUG_ON(i >= COMEDI_NUM_SUBDEVICE_MINORS); mutex_lock(&comedi_subdevice_minor_table_lock); s = comedi_subdevice_minor_table[i]; + if (s && s->device != dev) + s = NULL; mutex_unlock(&comedi_subdevice_minor_table_lock); return s; } @@ -229,10 +231,8 @@ comedi_read_subdevice(const struct comedi_device *dev, unsigned int minor) struct comedi_subdevice *s; if (minor >= COMEDI_NUM_BOARD_MINORS) { - s = comedi_subdevice_from_minor(minor); - if (!s || s->device != dev) - return NULL; - if (s->subdev_flags & SDF_CMD_READ) + s = comedi_subdevice_from_minor(dev, minor); + if (s == NULL || (s->subdev_flags & SDF_CMD_READ)) return s; } return dev->read_subdev; @@ -244,10 +244,8 @@ comedi_write_subdevice(const struct comedi_device *dev, unsigned int minor) struct comedi_subdevice *s; if (minor >= COMEDI_NUM_BOARD_MINORS) { - s = comedi_subdevice_from_minor(minor); - if (!s || s->device != dev) - return NULL; - if (s->subdev_flags & SDF_CMD_WRITE) + s = comedi_subdevice_from_minor(dev, minor); + if (s == NULL || (s->subdev_flags & SDF_CMD_WRITE)) return s; } return dev->write_subdev; |