[patch 22/26] sis5513: fix PIO setup for ATAPI devices

Greg KH
2009-10-09T23:19:21Z

[-- Attachment #1: sis5513-fix-pio-setup-for-atapi-devices.patch --]
[-- Type: text/plain, Size: 1969 bytes --]

2.6.31-stable review patch. If anyone has any objections, please let us know.

------------------
From: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

commit e13ee546bb06453939014c7b854e77fb643fd6f1 upstream.

Clear prefetch setting before potentially (re-)enabling it in
config_drive_art_rwp() so the transition of the device type on
the port from ATA to ATAPI (i.e. during warm-plug operation)
is handled correctly.

This is a really old bug (it probably goes back to very early
days of the driver) but it was only affecting warm-plug operation
until the recent "ide: try to use PIO Mode 0 during probe if
possible" change (commit 6029336426a2b43e4bc6f4a84be8789a047d139e).

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Tested-by: David Fries <david@fries.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
drivers/ide/sis5513.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)

--- a/drivers/ide/sis5513.c
+++ b/drivers/ide/sis5513.c
@@ -2,7 +2,7 @@
* Copyright (C) 1999-2000 Andre Hedrick <andre@linux-ide.org>
* Copyright (C) 2002 Lionel Bouton <Lionel.Bouton@inet6.fr>, Maintainer
* Copyright (C) 2003 Vojtech Pavlik <vojtech@suse.cz>
- * Copyright (C) 2007 Bartlomiej Zolnierkiewicz
+ * Copyright (C) 2007-2009 Bartlomiej Zolnierkiewicz
*
* May be copied or modified under the terms of the GNU General Public License
*
@@ -281,11 +281,13 @@ static void config_drive_art_rwp(ide_dri

pci_read_config_byte(dev, 0x4b, &reg4bh);

+ rw_prefetch = reg4bh & ~(0x11 << drive->dn);
+
if (drive->media == ide_disk)
- rw_prefetch = 0x11 << drive->dn;
+ rw_prefetch |= 0x11 << drive->dn;

- if ((reg4bh & (0x11 << drive->dn)) != rw_prefetch)
- pci_write_config_byte(dev, 0x4b, reg4bh|rw_prefetch);
+ if (reg4bh != rw_prefetch)
+ pci_write_config_byte(dev, 0x4b, rw_prefetch);
}

static void sis_set_pio_mode(ide_drive_t *drive, const u8 pio)