This is a note to let you know that I've just added the patch titled
ata: pata_legacy: fix pdc20230_set_piomode()
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
ata-pata_legacy-fix-pdc20230_set_piomode.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit dcc0d6654ee44226765d50f1ac13fe79f4ef39a7
Author: Sergey Shtylyov <s.shtylyov@xxxxxx>
Date: Sat Oct 29 00:07:06 2022 +0300
ata: pata_legacy: fix pdc20230_set_piomode()
[ Upstream commit 171a93182eccd6e6835d2c86b40787f9f832efaa ]
Clang gives a warning when compiling pata_legacy.c with 'make W=1' about
the 'rt' local variable in pdc20230_set_piomode() being set but unused.
Quite obviously, there is an outb() call missing to write back the updated
variable. Moreover, checking the docs by Petr Soucek revealed that bitwise
AND should have been done with a negated timing mask and the master/slave
timing masks were swapped while updating...
Fixes: 669a5db411d8 ("[libata] Add a bunch of PATA drivers.")
Reported-by: Damien Le Moal <damien.lemoal@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Sergey Shtylyov <s.shtylyov@xxxxxx>
Signed-off-by: Damien Le Moal <damien.lemoal@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/ata/pata_legacy.c b/drivers/ata/pata_legacy.c
index 55fcdb798002..e4071768333d 100644
--- a/drivers/ata/pata_legacy.c
+++ b/drivers/ata/pata_legacy.c
@@ -292,9 +292,10 @@ static void pdc20230_set_piomode(struct ata_port *ap, struct ata_device *adev)
outb(inb(0x1F4) & 0x07, 0x1F4);
rt = inb(0x1F3);
- rt &= 0x07 << (3 * adev->devno);
+ rt &= ~(0x07 << (3 * !adev->devno));
if (pio)
- rt |= (1 + 3 * pio) << (3 * adev->devno);
+ rt |= (1 + 3 * pio) << (3 * !adev->devno);
+ outb(rt, 0x1F3);
udelay(100);
outb(inb(0x1F2) | 0x01, 0x1F2);
