comedi: pcl711: Add sanity checks for I/O base address

The "pcl711" driver uses an admin-supplied configuration option
(`it->options[0]`) to configure the I/O port base address of an
Advantech PCL-711 series board or an Adlink ACL-8112 series board.  It
currently allows any base address to be configured but the hardware only
supports base addresses (configured by on-board DIP switches) in the
range 0 to 0x3F0 (for PCL-711) or 0x200 to 0x3F0 (for ACL-8112) on
16-byte boundaries.

Store the minimum supported I/O base address in the static board
information array elements, and add a sanity check to ensure the device
is not configured at an unsupported base address.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://patch.msgid.link/20260130170416.49994-33-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/comedi/drivers/pcl711.c b/drivers/comedi/drivers/pcl711.c
index 0cf3917defe790213342008017ef0a2a1adaa657..5d2c4b2aa3bb6590709730307e1dc7312814b255 100644 (file)
--- a/drivers/comedi/drivers/pcl711.c
+++ b/drivers/comedi/drivers/pcl711.c
@@ -112,6 +112,7 @@ struct pcl711_board {
        int n_aichan;
        int n_aochan;
        int maxirq;
+       unsigned int min_io_start;
        const struct comedi_lrange *ai_range_type;
 };
 
@@ -132,12 +133,14 @@ static const struct pcl711_board boardtypes[] = {
                .n_aichan       = 16,
                .n_aochan       = 2,
                .maxirq         = 15,
+               .min_io_start   = 0x200,
                .ai_range_type  = &range_acl8112hg_ai,
        }, {
                .name           = "acl8112dg",
                .n_aichan       = 16,
                .n_aochan       = 2,
                .maxirq         = 15,
+               .min_io_start   = 0x200,
                .ai_range_type  = &range_acl8112dg_ai,
        },
 };
@@ -418,7 +421,8 @@ static int pcl711_attach(struct comedi_device *dev, struct comedi_devconfig *it)
        struct comedi_subdevice *s;
        int ret;
 
-       ret = comedi_request_region(dev, it->options[0], 0x10);
+       ret = comedi_check_request_region(dev, it->options[0], 0x10,
+                                         board->min_io_start, 0x3ff, 16);
        if (ret)
                return ret;