Commit e1ddb4b6 authored by Alan Cox's avatar Alan Cox Committed by Jeff Garzik
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[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: default avatarAlan 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: default avatarAlan Cox <alan@redhat.com>

Combined into a single changeset and
Signed-off-by: default avatarJeff Garzik <jeff@garzik.org>
parent 6d32d30f

drivers/ata/libata-acpi.c

+38 −0
Original line number Diff line number Diff line
@@ -296,6 +296,44 @@ static int ata_dev_get_GTF(struct ata_device *dev, struct ata_acpi_gtf **gtf, 
	return rc;

}



/**

 * 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

include/linux/libata.h

+6 −0
Original line number Diff line number Diff line
@@ -885,6 +885,12 @@ enum { 
				  ATA_TIMING_CYCLE | ATA_TIMING_UDMA,

};



/* libata-acpi.c */

#ifdef CONFIG_ATA_ACPI

extern int ata_acpi_cbl_80wire(struct ata_port *ap);

#else

static inline int ata_acpi_cbl_80wire(struct ata_port *ap) { return 0; }

#endif



#ifdef CONFIG_PCI

struct pci_bits {

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