[<prev] [next>] [day] [month] [year] [list]
Message-Id: <46C05C8A.76E4.0078.0@novell.com>
Date: Mon, 13 Aug 2007 12:28:42 +0100
From: "Jan Beulich" <jbeulich@...ell.com>
To: <linux-kernel@...r.kernel.org>
Subject: [PATCH] floppy: tolerate DMA channel unavailability
The floppy driver is already written to be able to operate in virtual
DMA mode. Thus it can easily be adjusted to tolerate failure from
fd_request_dma() as long as virtual DMA mode is not disallowed.
Signed-off-by: Jan Beulich <jbeulich@...ell.com>
drivers/block/floppy.c | 14 +++++++++-----
1 files changed, 9 insertions(+), 5 deletions(-)
--- linux-2.6.23-rc3/drivers/block/floppy.c 2007-08-13 08:59:58.000000000 +0200
+++ 2.6.23-rc3-floppy-no-dma/drivers/block/floppy.c 2007-08-07 10:40:43.000000000 +0200
@@ -4397,11 +4397,15 @@ static int floppy_grab_irq_and_dma(void)
if (fd_request_dma()) {
DPRINT("Unable to grab DMA%d for the floppy driver\n",
FLOPPY_DMA);
- fd_free_irq();
- spin_lock_irqsave(&floppy_usage_lock, flags);
- usage_count--;
- spin_unlock_irqrestore(&floppy_usage_lock, flags);
- return -1;
+ if (can_use_virtual_dma & 2)
+ use_virtual_dma = can_use_virtual_dma = 1;
+ if (!(can_use_virtual_dma & 1)) {
+ fd_free_irq();
+ spin_lock_irqsave(&floppy_usage_lock, flags);
+ usage_count--;
+ spin_unlock_irqrestore(&floppy_usage_lock, flags);
+ return -1;
+ }
}
for (fdc = 0; fdc < N_FDC; fdc++) {
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists