diff options
| author | Tejun Heo <htejun@gmail.com> | 2007-12-15 15:05:02 +0900 |
|---|---|---|
| committer | Jeff Garzik <jeff@garzik.org> | 2007-12-17 20:33:14 -0500 |
| commit | c05e6ff035c1b25d17364a685432b33937d3dc23 (patch) | |
| tree | 08c9171d024b6659b29a4f9f7d95318430b75b6a /include/linux | |
| parent | 562f0c2d771ee7be6b37fe015f94a929f8056120 (diff) | |
libata-acpi: implement and use ata_acpi_init_gtm()
_GTM fetches currently configured transfer mode while _STM configures
controller according to _GTM parameter and prepares transfer mode
configuration TFs for _GTF. In many cases _GTM and _STM
implementations are quite brittle and can't cope with configuration
changed by libata.
libata does not depend on ATA ACPI to configure devices. The only
reason libata performs _GTM and _STM are to make _GTF evaluation
succeed and libata also doesn't care about how _GTF TFs configure
transfer mode. It overrides that configuration anyway, so from
libata's POV, it doesn't matter what value is feeded to _STM as long
as evaluation succeeds for _STM and following _GTF.
This patch adds dev->__acpi_init_gtm and store initial _GTM values on
host initialization before modified by reset and mode configuration.
If the field is valid, ata_acpi_init_gtm() returns pointer to the
saved _GTM structure; otherwise, NULL.
This saved value is used for _STM during resume and peek at
BIOS/firmware programmed initial timing for later use. The accessor
is there to make building w/o ACPI easy as dev->__acpi_init doesn't
exist if ACPI is not enabled.
On driver detach, the initial BIOS configuration is restored by
executing _STM with the initial _GTM values such that the next driver
can also use the initial BIOS configured values.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/libata.h | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/include/linux/libata.h b/include/linux/libata.h index 3784af395576..ba84d8a37545 100644 --- a/include/linux/libata.h +++ b/include/linux/libata.h @@ -211,7 +211,7 @@ enum { ATA_PFLAG_SUSPENDED = (1 << 17), /* port is suspended (power) */ ATA_PFLAG_PM_PENDING = (1 << 18), /* PM operation pending */ - ATA_PFLAG_GTM_VALID = (1 << 19), /* acpi_gtm data valid */ + ATA_PFLAG_INIT_GTM_VALID = (1 << 19), /* initial gtm data valid */ /* struct ata_queued_cmd flags */ ATA_QCFLAG_ACTIVE = (1 << 0), /* cmd not yet ack'd to scsi lyer */ @@ -653,7 +653,7 @@ struct ata_port { #ifdef CONFIG_ATA_ACPI acpi_handle acpi_handle; - struct ata_acpi_gtm acpi_gtm; + struct ata_acpi_gtm __acpi_init_gtm; /* use ata_acpi_init_gtm() */ #endif u8 sector_buf[ATA_SECT_SIZE]; /* owned by EH */ }; @@ -939,10 +939,20 @@ enum { /* libata-acpi.c */ #ifdef CONFIG_ATA_ACPI +static inline const struct ata_acpi_gtm *ata_acpi_init_gtm(struct ata_port *ap) +{ + if (ap->pflags & ATA_PFLAG_INIT_GTM_VALID) + return &ap->__acpi_init_gtm; + return NULL; +} extern int ata_acpi_cbl_80wire(struct ata_port *ap); int ata_acpi_stm(struct ata_port *ap, const struct ata_acpi_gtm *stm); int ata_acpi_gtm(struct ata_port *ap, struct ata_acpi_gtm *stm); #else +static inline const struct ata_acpi_gtm *ata_acpi_init_gtm(struct ata_port *ap) +{ + return NULL; +} static inline int ata_acpi_cbl_80wire(struct ata_port *ap) { return 0; } #endif |