2023-09-13 20:21:44

by Ian Abbott

[permalink] [raw]
Subject: [PATCH 12/13] comedi: amplc_dio200_common: Conditionally remove I/O port support

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 amplc_dio200_common module is used by the amplc_dio200 module (for
ISA cards) and the amplc_dio200_pci module (for PCI and PCI Express
cards). It supports both port I/O and memory-mapped I/O.

Port I/O and memory-mapped I/O is confined to the `dio200___read8()`,
`dio200___read32()`, `dio200___write8()` and `dio200___write32()`
functions. Conditionally compile two versions of those functions. If
the `CONFIG_HAS_PORTIO` macro is defined, call either the port I/O or
memory mapped I/O functions depending on the `mmio` member of the
`struct comedi_device`. If the `CONFIG_HAS_PORTIO` macro is undefined
only call the memory-mapped I/O functions.

Add a run-time check to `amplc_dio200_common_attach()` to return an
error if the device wants to use port I/O when the `CONFIG_HAS_PORTIO`
macro is undefined.

The changes allow the module to be built even if the port I/O functions
have not been declared.

Cc: Arnd Bergmann <[email protected]>
Cc: Niklas Schnelle <[email protected]>
Signed-off-by: Ian Abbott <[email protected]>
---
drivers/comedi/drivers/amplc_dio200_common.c | 36 ++++++++++++++++++++
1 file changed, 36 insertions(+)

diff --git a/drivers/comedi/drivers/amplc_dio200_common.c b/drivers/comedi/drivers/amplc_dio200_common.c
index e6d63e89e7bf..b1a9b4c4a185 100644
--- a/drivers/comedi/drivers/amplc_dio200_common.c
+++ b/drivers/comedi/drivers/amplc_dio200_common.c
@@ -86,6 +86,8 @@ struct dio200_subdev_intr {
unsigned int active:1;
};

+#ifdef CONFIG_HAS_IOPORT
+
static unsigned char dio200___read8(struct comedi_device *dev,
unsigned int offset)
{
@@ -120,6 +122,34 @@ static void dio200___write32(struct comedi_device *dev,
outl(val, dev->iobase + offset);
}

+#else /* CONFIG_HAS_IOPORT */
+
+static unsigned char dio200___read8(struct comedi_device *dev,
+ unsigned int offset)
+{
+ return readb(dev->mmio + offset);
+}
+
+static void dio200___write8(struct comedi_device *dev,
+ unsigned int offset, unsigned char val)
+{
+ writeb(val, dev->mmio + offset);
+}
+
+static unsigned int dio200___read32(struct comedi_device *dev,
+ unsigned int offset)
+{
+ return readl(dev->mmio + offset);
+}
+
+static void dio200___write32(struct comedi_device *dev,
+ unsigned int offset, unsigned int val)
+{
+ writel(val, dev->mmio + offset);
+}
+
+#endif /* CONFIG_HAS_IOPORT */
+
static unsigned char dio200_read8(struct comedi_device *dev,
unsigned int offset)
{
@@ -803,6 +833,12 @@ int amplc_dio200_common_attach(struct comedi_device *dev, unsigned int irq,
unsigned int n;
int ret;

+ if (!IS_ENABLED(CONFIG_HAS_IOPORT) && !dev->mmio) {
+ dev_err(dev->class_dev,
+ "error! need I/O port support\n");
+ return -ENXIO;
+ }
+
ret = comedi_alloc_subdevices(dev, board->n_subdevs);
if (ret)
return ret;
--
2.40.1