UIO: Add write function to allow irq masking
Sometimes it is necessary to enable/disable the interrupt of a UIO device
from the userspace part of the driver. With this patch, the UIO kernel driver
can implement an "irqcontrol()" function that does this. Userspace can write
an s32 value to /dev/uioX (usually 0 or 1 to turn the irq off or on). The
UIO core will then call the driver's irqcontrol function.
Signed-off-by: Hans J. Koch <hjk@linutronix.de>
Acked-by: Uwe Kleine-König <Uwe.Kleine-Koenig@digi.com>
Acked-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/include/linux/uio_driver.h b/include/linux/uio_driver.h
index 973386d..cf65e96 100644
--- a/include/linux/uio_driver.h
+++ b/include/linux/uio_driver.h
@@ -53,6 +53,7 @@
* @mmap: mmap operation for this uio device
* @open: open operation for this uio device
* @release: release operation for this uio device
+ * @irqcontrol: disable/enable irqs when 0/1 is written to /dev/uioX
*/
struct uio_info {
struct uio_device *uio_dev;
@@ -66,6 +67,7 @@
int (*mmap)(struct uio_info *info, struct vm_area_struct *vma);
int (*open)(struct uio_info *info, struct inode *inode);
int (*release)(struct uio_info *info, struct inode *inode);
+ int (*irqcontrol)(struct uio_info *info, s32 irq_on);
};
extern int __must_check