comedi: 8255_pci: Conditionally remove devices that use port I/O

In a future patch, the port I/O functions (`inb()`, `outb()`, and
friends will only be declared in the `HAS_IOPORT` configuration option
is enabled.

The 8255_pci module supports PCI digital I/O devices from various
manufacturers that consist of one or more 8255 Programmable Peripheral
Interface chips (or equivalent hardware) to provide their digital I/O
ports.  Some of the devices use port I/O and some only use memory-mapped
I/O.

Conditionally compile in support for the devices that need port I/O if
and only if the `CONFIG_HAS_IOPORT` macro is defined.  Change
`pci_8255_auto_attach()` to return an error if the device actually
requires port I/O (based on the PCI BAR resource flags) but the
`HAS_IOPORT` configuration is not enabled.

Cc: Arnd Bergmann <arnd@kernel.org>
Cc: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://lore.kernel.org/r/20230913170712.111719-6-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: ian-abbott

drivers/comedi/drivers/8255_pci.c

@@ -57,6 +57,7 @@
 #include <linux/comedi/comedi_8255.h>
 
 enum pci_8255_boardid {
+#ifdef CONFIG_HAS_IOPORT
 	BOARD_ADLINK_PCI7224,
 	BOARD_ADLINK_PCI7248,
 	BOARD_ADLINK_PCI7296,
@@ -65,6 +66,7 @@ enum pci_8255_boardid {
 	BOARD_CB_PCIDIO48H_OLD,
 	BOARD_CB_PCIDIO48H_NEW,
 	BOARD_CB_PCIDIO96H,
+#endif	/* CONFIG_HAS_IOPORT */
 	BOARD_NI_PCIDIO96,
 	BOARD_NI_PCIDIO96B,
 	BOARD_NI_PXI6508,
@@ -82,6 +84,7 @@ struct pci_8255_boardinfo {
 };
 
 static const struct pci_8255_boardinfo pci_8255_boards[] = {
+#ifdef CONFIG_HAS_IOPORT
 	[BOARD_ADLINK_PCI7224] = {
 		.name		= "adl_pci-7224",
 		.dio_badr	= 2,
@@ -122,6 +125,7 @@ static const struct pci_8255_boardinfo pci_8255_boards[] = {
 		.dio_badr	= 2,
 		.n_8255		= 4,
 	},
+#endif	/* CONFIG_HAS_IOPORT */
 	[BOARD_NI_PCIDIO96] = {
 		.name		= "ni_pci-dio-96",
 		.dio_badr	= 1,
@@ -219,8 +223,11 @@ static int pci_8255_auto_attach(struct comedi_device *dev,
 		dev->mmio = pci_ioremap_bar(pcidev, board->dio_badr);
 		if (!dev->mmio)
 			return -ENOMEM;
-	} else {
+	} else if (IS_ENABLED(CONFIG_HAS_IOPORT)) {
 		dev->iobase = pci_resource_start(pcidev, board->dio_badr);
+	} else {
+		dev_err(dev->class_dev, "error! need I/O port support\n");
+		return -ENXIO;
 	}
 
 	/*
@@ -259,6 +266,7 @@ static int pci_8255_pci_probe(struct pci_dev *dev,
 }
 
 static const struct pci_device_id pci_8255_pci_table[] = {
+#ifdef CONFIG_HAS_IOPORT
 	{ PCI_VDEVICE(ADLINK, 0x7224), BOARD_ADLINK_PCI7224 },
 	{ PCI_VDEVICE(ADLINK, 0x7248), BOARD_ADLINK_PCI7248 },
 	{ PCI_VDEVICE(ADLINK, 0x7296), BOARD_ADLINK_PCI7296 },
@@ -269,6 +277,7 @@ static const struct pci_device_id pci_8255_pci_table[] = {
 	{ PCI_DEVICE_SUB(PCI_VENDOR_ID_CB, 0x000b, PCI_VENDOR_ID_CB, 0x000b),
 	  .driver_data = BOARD_CB_PCIDIO48H_NEW },
 	{ PCI_VDEVICE(CB, 0x0017), BOARD_CB_PCIDIO96H },
+#endif	/* CONFIG_HAS_IOPORT */
 	{ PCI_VDEVICE(NI, 0x0160), BOARD_NI_PCIDIO96 },
 	{ PCI_VDEVICE(NI, 0x1630), BOARD_NI_PCIDIO96B },
 	{ PCI_VDEVICE(NI, 0x13c0), BOARD_NI_PXI6508 },