From c05e6ff035c1b25d17364a685432b33937d3dc23 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Sat, 15 Dec 2007 15:05:02 +0900 Subject: 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 Signed-off-by: Jeff Garzik --- include/linux/libata.h | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) (limited to 'include') 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 -- cgit v1.2.3-59-g8ed1b