The "pcmmio" driver uses an admin-supplied configuration option
(`it->options[0]`) to configure the I/O port base address of a
PCM-UIO48A or PCM-UIO96A board.  It will probably work with the later
PCM-UIO48C and PCM-UIO96C boards.  It currently allows any base address
to be configured but the hardware only supports base addresses
(configured by on-board jumpers) in the range 0 to 0xFFF0 on 16-byte
boundaries (for PCM-UIO48C) or 0 to 0xFFE0 on 32-byte boundaries (for
PCM-UIO96C).  (The PCM-UIO48A supports base addresses up to 0xFF0 and
the PCI-UIO96A supports base addresses up to 0x7E0.)

Add a sanity check to ensure the device is not configured at an
unsupported base address (allowing for the extended range of the "C"
models).

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
---
 drivers/comedi/drivers/pcmuio.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/comedi/drivers/pcmuio.c b/drivers/comedi/drivers/pcmuio.c
index 33b24dbbb919..0995911a3ea3 100644
--- a/drivers/comedi/drivers/pcmuio.c
+++ b/drivers/comedi/drivers/pcmuio.c
@@ -521,11 +521,12 @@ static int pcmuio_attach(struct comedi_device *dev, struct comedi_devconfig *it)
 	const struct pcmuio_board *board = dev->board_ptr;
 	struct comedi_subdevice *s;
 	struct pcmuio_private *devpriv;
+	unsigned int io_len = board->num_asics * PCMUIO_ASIC_IOSIZE;
 	int ret;
 	int i;
 
-	ret = comedi_request_region(dev, it->options[0],
-				    board->num_asics * PCMUIO_ASIC_IOSIZE);
+	ret = comedi_check_request_region(dev, it->options[0], io_len,
+					  0, 0xffff, io_len);
 	if (ret)
 		return ret;
 
-- 
2.51.0