[PATCH 28/46] comedi: ni_at_ao: Add sanity checks for I/O base address

[Ian Abbott]

The "ni_at_ao" driver uses an admin-supplied configuration option
(`it->options[0]`) to configure the I/O port base address of an AT-AO-6
or AT-AO-10 board.  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 0x3E0 on 32-byte boundaries.

Add a sanity check to ensure the device is not configured at an
unsupported base address.

Signed-off-by: Ian Abbott <abbotti@xxxxxxxxx>
---
 drivers/comedi/drivers/ni_at_ao.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/comedi/drivers/ni_at_ao.c b/drivers/comedi/drivers/ni_at_ao.c
index 9cf6b4ff6b65..31fd64bf8206 100644
--- a/drivers/comedi/drivers/ni_at_ao.c
+++ b/drivers/comedi/drivers/ni_at_ao.c
@@ -295,7 +295,8 @@ static int atao_attach(struct comedi_device *dev, struct comedi_devconfig *it)
 	struct comedi_subdevice *s;
 	int ret;
 
-	ret = comedi_request_region(dev, it->options[0], 0x20);
+	ret = comedi_check_request_region(dev, it->options[0], 0x20,
+					  0, 0x3ff, 32);
 	if (ret)
 		return ret;
 
-- 
2.51.0