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authorAlan Cox <alan@lxorguk.ukuu.org.uk>2007-08-16 02:33:36 -0400
committerJeff Garzik <jeff@garzik.org>2007-10-12 14:55:34 -0400
commite1ddb4b6a2c9b2c72991eb8640ef2f50691ac502 (patch)
treefd9d0f14c5a5e329f4c1d2ee737177c5caf24b02 /drivers/ata/libata-acpi.c
parent6d32d30f55020d766388df7515f771f68c973033 (diff)
downloadlwn-e1ddb4b6a2c9b2c72991eb8640ef2f50691ac502.tar.gz
lwn-e1ddb4b6a2c9b2c72991eb8640ef2f50691ac502.zip
[libata] add ACPI cable detect API
Combined from two Alan Cox patches: 1) libata: ACPI checks for 80wire cable We can use the ACPI mode information with several drivers as a hint to cable type. If the ACPI mode set by the BIOS is faster than UDMA33 then we know the BIOS thinks there are 80wire cables. If it doesn't set such a mode or it has no ACPI method then we get no further information and can rely on existing approaches Introduce the function headers needed. Null it out for non ACPI boxes Signed-off-by: Alan Cox <alan@redhat.com> 2) libata: ACPI checks for 80wire cable Provide actual methods for checking if the ACPI support thinks the cable is 80wire, or doesn't know Signed-off-by: Alan Cox <alan@redhat.com> Combined into a single changeset and Signed-off-by: Jeff Garzik <jeff@garzik.org>
Diffstat (limited to 'drivers/ata/libata-acpi.c')
-rw-r--r--drivers/ata/libata-acpi.c38
1 files changed, 38 insertions, 0 deletions
diff --git a/drivers/ata/libata-acpi.c b/drivers/ata/libata-acpi.c
index 43af2e06d446..dc9842ec6f06 100644
--- a/drivers/ata/libata-acpi.c
+++ b/drivers/ata/libata-acpi.c
@@ -297,6 +297,44 @@ static int ata_dev_get_GTF(struct ata_device *dev, struct ata_acpi_gtf **gtf,
}
/**
+ * ata_acpi_cbl_80wire - Check for 80 wire cable
+ * @ap: Port to check
+ *
+ * Return 1 if the ACPI mode data for this port indicates the BIOS selected
+ * an 80wire mode.
+ */
+
+int ata_acpi_cbl_80wire(struct ata_port *ap)
+{
+ struct ata_acpi_gtm gtm;
+ int valid = 0;
+
+ /* No _GTM data, no information */
+ if (ata_acpi_gtm(ap, &gtm) < 0)
+ return 0;
+
+ /* Split timing, DMA enabled */
+ if ((gtm.flags & 0x11) == 0x11 && gtm.drive[0].dma < 55)
+ valid |= 1;
+ if ((gtm.flags & 0x14) == 0x14 && gtm.drive[1].dma < 55)
+ valid |= 2;
+ /* Shared timing, DMA enabled */
+ if ((gtm.flags & 0x11) == 0x01 && gtm.drive[0].dma < 55)
+ valid |= 1;
+ if ((gtm.flags & 0x14) == 0x04 && gtm.drive[0].dma < 55)
+ valid |= 2;
+
+ /* Drive check */
+ if ((valid & 1) && ata_dev_enabled(&ap->link.device[0]))
+ return 1;
+ if ((valid & 2) && ata_dev_enabled(&ap->link.device[1]))
+ return 1;
+ return 0;
+}
+
+EXPORT_SYMBOL_GPL(ata_acpi_cbl_80wire);
+
+/**
* taskfile_load_raw - send taskfile registers to host controller
* @dev: target ATA device
* @gtf: raw ATA taskfile register set (0x1f1 - 0x1f7)