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: 669a5db ("[libata] Add a bunch of PATA drivers.") Reported-by: Damien Le Moal <[email protected]> Signed-off-by: Sergey Shtylyov <[email protected]> Signed-off-by: Damien Le Moal <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
zeelog · Nov 10, 2022 · e4b7e0d · e4b7e0d
1 parent 72a20bc
commit e4b7e0d
Showing 1 changed file with 3 additions and 2 deletions.
diff --git 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);