comedi: pcl724: Add sanity checks for I/O base address

The "pcl724" driver uses an admin-supplied configuration option
(`it->options[0]`) to configure the I/O port base address of various
8255 chip-based digital I/O ISA boards from Advantech, ADLINK,
WinSystems, and Diamond Systems.  It currently allows any base address
to be configured but the hardware only supports base addresses
(configured by on-board DIP switches or jumpers) in various ranges, and
on various alignment boundaries, depending on the model.

Store the minimum and maximum supported I/O address ranges in the static
board information array elements (the required alignment is already
stored in the `io_range` member), 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/20260130170416.49994-34-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/comedi/drivers/pcl724.c b/drivers/comedi/drivers/pcl724.c
index 00474710b81fd633312ea896ec0f58295b12f636..9707d0c893049330dd74486c81662c853c3a779c 100644 (file)
--- a/drivers/comedi/drivers/pcl724.c
+++ b/drivers/comedi/drivers/pcl724.c
@@ -31,6 +31,8 @@
 struct pcl724_board {
        const char *name;
        unsigned int io_range;
+       unsigned int min_io_start;
+       unsigned int max_io_end;
        unsigned int can_have96:1;
        unsigned int is_pet48:1;
        int numofports;
@@ -40,37 +42,53 @@ static const struct pcl724_board boardtypes[] = {
        {
                .name           = "pcl724",
                .io_range       = 0x04,
+               .min_io_start   = 0x200,
+               .max_io_end     = 0x3ff,
                .numofports     = 1,    /* 24 DIO channels */
        }, {
                .name           = "pcl722",
                .io_range       = 0x20,
+               .min_io_start   = 0x200,
+               .max_io_end     = 0x3ff,
                .can_have96     = 1,
                .numofports     = 6,    /* 144 (or 96) DIO channels */
        }, {
                .name           = "pcl731",
                .io_range       = 0x08,
+               .min_io_start   = 0,
+               .max_io_end     = 0x3ff,
                .numofports     = 2,    /* 48 DIO channels */
        }, {
                .name           = "acl7122",
                .io_range       = 0x20,
+               .min_io_start   = 0x200,
+               .max_io_end     = 0x3ff,
                .can_have96     = 1,
                .numofports     = 6,    /* 144 (or 96) DIO channels */
        }, {
                .name           = "acl7124",
                .io_range       = 0x04,
+               .min_io_start   = 0x200,
+               .max_io_end     = 0x3ff,
                .numofports     = 1,    /* 24 DIO channels */
        }, {
                .name           = "pet48dio",
                .io_range       = 0x02,
+               .min_io_start   = 0,
+               .max_io_end     = 0x3ff,
                .is_pet48       = 1,
                .numofports     = 2,    /* 48 DIO channels */
        }, {
                .name           = "pcmio48",
                .io_range       = 0x08,
+               .min_io_start   = 0x100,
+               .max_io_end     = 0x17f,
                .numofports     = 2,    /* 48 DIO channels */
        }, {
                .name           = "onyx-mm-dio",
                .io_range       = 0x10,
+               .min_io_start   = 0,
+               .max_io_end     = 0x3ff,
                .numofports     = 2,    /* 48 DIO channels */
        },
 };
@@ -112,7 +130,9 @@ static int pcl724_attach(struct comedi_device *dev,
                n_subdevices = 4;
        }
 
-       ret = comedi_request_region(dev, it->options[0], iorange);
+       ret = comedi_check_request_region(dev, it->options[0], iorange,
+                                         board->min_io_start,
+                                         board->max_io_end, iorange);
        if (ret)
                return ret;