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pata_cs5536: add quirk for broken udma

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I am working on a device which uses the cs5536 pata driver. There
are some broken hardware revisions out in the field, which can be
detected via DMI. On older versions with an embedded BIOS I
used libata.dma=0 to disable dma completely.
Now we are switching to a coreboot/seabios based BIOS where we
have DMI support and so I think its a good idea to get rid of
all those hacky kernel parameters as the same image
is used other devices where libata.dma=0 is not a good idea.

Signed-off-by: Christian Gmeiner <christian.gmeiner@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
This commit is contained in:
Christian Gmeiner 2012-10-09 17:53:12 +02:00 committed by Jeff Garzik
parent d9904344fc
commit abf8f2b877
1 changed files with 31 additions and 1 deletions
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32
drivers/ata/pata_cs5536.c
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@ -38,6 +38,7 @@
#include <linux/delay.h>
#include <linux/libata.h>
#include <scsi/scsi_host.h>
#include <linux/dmi.h>
#ifdef CONFIG_X86_32
#include <asm/msr.h>
@ -80,6 +81,21 @@ enum {
IDE_ETC_UDMA_MASK = 0xc0,
};
/* Some Bachmann OT200 devices have a non working UDMA support due a
* missing resistor.
*/
static const struct dmi_system_id udma_quirk_dmi_table[] = {
{
.ident = "Bachmann electronic OT200",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Bachmann electronic"),
DMI_MATCH(DMI_PRODUCT_NAME, "OT200"),
DMI_MATCH(DMI_PRODUCT_VERSION, "1")
},
},
{ }
};
static int cs5536_read(struct pci_dev *pdev, int reg, u32 *val)
{
if (unlikely(use_msr)) {
@ -242,9 +258,23 @@ static int cs5536_init_one(struct pci_dev *dev, const struct pci_device_id *id)
.port_ops = &cs5536_port_ops,
};
const struct ata_port_info *ppi[] = { &info, &ata_dummy_port_info };
static const struct ata_port_info no_udma_info = {
.flags = ATA_FLAG_SLAVE_POSS,
.pio_mask = ATA_PIO4,
.port_ops = &cs5536_port_ops,
};
const struct ata_port_info *ppi[2];
u32 cfg;
if (dmi_check_system(udma_quirk_dmi_table))
ppi[0] = &no_udma_info;
else
ppi[0] = &info;
ppi[1] = &ata_dummy_port_info;
if (use_msr)
printk(KERN_ERR DRV_NAME ": Using MSR regs instead of PCI\n");