[patch 2/3] pata_atiixp: simplex clear

[patch 2/3] pata_atiixp: simplex clear

[akpm]

From: Alan Cox <alan@lxorguk.ukuu.org.uk>

Some of the other quirks changes seem to have left some users with the simplex
bits mis-set by the time the driver loads.  Clear simplex mode before we probe
the controller therefore.

[akpm@linux-foundation.org: fix build after upstream renamed things]
Signed-off-by: Alan Cox <alan@redhat.com>
Cc: Jeff Garzik <jeff@garzik.org>

On Sat, 29 Mar 2008 12:15:40 -0400 Jeff Garzik <jeff@garzik.org> wrote:
> This patch triggered an audit which led me to... bug city.
> 
> 1) This call occurs before resources are guaranteed to be present, which 
> happens when pci[m]_enable_device() is called.
> 
> 2) Auditing the other ata_pci_clear_simplex() uses, it seems the others 
> are equally broken.
> 
> 3) Further, looking at pata_amd, I notice that the resume code twiddles 
> bits before the PCI device is even bought into D0 state!
> 
> 4) ata_pci_clear_simplex() does its work before resources are mapped, 
> and assumes PCI IDE and PCI BAR #4 behavior.  This works at present, but 
> is less robust than it could be.
> 
> 
> Anyway, my suggestion would be to add a "post-enable" function pointer 
> to ata_pci_init_one() arguments, and call ata_pci_clear_simplex() from 
> that hook.  That would permit this patch and other 
> ata_pci_clear_simplex() callsites to be fixed.
> 
> 	Jeff
> 

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 drivers/ata/pata_atiixp.c |    7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff -puN drivers/ata/pata_atiixp.c~pata_atiixp-simplex-clear drivers/ata/pata_atiixp.c
--- a/drivers/ata/pata_atiixp.c~pata_atiixp-simplex-clear
+++ a/drivers/ata/pata_atiixp.c
@@ -22,7 +22,7 @@
 #include <linux/libata.h>
 
 #define DRV_NAME "pata_atiixp"
-#define DRV_VERSION "0.4.6"
+#define DRV_VERSION "0.4.7"
 
 enum {
 	ATIIXP_IDE_PIO_TIMING	= 0x40,
@@ -243,6 +243,9 @@ static int atiixp_init_one(struct pci_de
 		.port_ops = &atiixp_port_ops
 	};
 	const struct ata_port_info *ppi[] = { &info, NULL };
+	/* Some of the quirk reconfiguration messes up the simplex flag, so
+	   clear it again */
+	ata_pci_bmdma_clear_simplex(dev);
 	return ata_pci_sff_init_one(dev, ppi, &atiixp_sht, NULL);
 }
 
@@ -279,7 +282,7 @@ static void __exit atiixp_exit(void)
 }
 
 MODULE_AUTHOR("Alan Cox");
-MODULE_DESCRIPTION("low-level driver for ATI IXP200/300/400");
+MODULE_DESCRIPTION("low-level driver for ATI IXP series");
 MODULE_LICENSE("GPL");
 MODULE_DEVICE_TABLE(pci, atiixp);
 MODULE_VERSION(DRV_VERSION);
_

Re: [patch 2/3] pata_atiixp: simplex clear

[Alan Cox]

On Fri, May 02, 2008 at 01:37:41PM -0700, akpm@linux-foundation.org wrote:
> From: Alan Cox <alan@lxorguk.ukuu.org.uk>
> 
> Some of the other quirks changes seem to have left some users with the simplex
> bits mis-set by the time the driver loads.  Clear simplex mode before we probe
> the controller therefore.

Self NAK this one. I turns out to be *far* more complicated and I sent
Jeff a replacement fix