From: Lv Zheng <lv.zheng@xxxxxxxxx>
This patch restores libata.noacpi support to libata-acpi.c.
There are broken optional control methods for ATA controller devices in the
real world. The libata.noacpi has been used for a long time as a
workaround to deal with issues caused by the broken ASL codes.
1. The "noacpi" option is introduced by the following commit:
commit 11ef697b37e3c85ce1ac21f7711babf1f5b12784
Date: Thu, 28 Sep 2006 11:29:01 -0700
Subject: libata: ACPI and _GTF support
2. The "noacpi" option is renamed to "libata_noacpi" by the following
commit:
commit d7d0dad62a641c156386288a747c1a2f6bb2e42d
Date: Wed, 28 Mar 2007 01:57:37 -0400
Subject: [libata] Disable ACPI by default; fix namespace problems
3. Some of its logics are changed over time - becomes relying on the
"acpi_handle" bound to the ATA devices since this commit:
commit fafbae87db88a73b166d3bc3294d209207f27056
Date: Tue, 15 May 2007 03:28:16 +0900
Subject: libata-acpi: implement ata_acpi_associate()
4. The option is deleted by the following commit:
commit 30dcf76acc695cbd2fa919e294670fe9552e16e7
Date: Mon, 25 Jun 2012 16:13:04 +0800
Subject: libata: migrate ACPI code over to new bindings
But the libata.noacpi setup is still left in the kernel without codes to
implement it. So the deletion introduces a regression to the Linux.
This patch disables ATA_ACPI support at runtime by stopping acpi binding
on the ATA devices to fix this regression.
This patch is tested by booting a SATA x86-64 kernel or a PATA x86 kernel
with or without "libata.noacpi=1" kernel command line argument.
Signed-off-by: Lv Zheng <lv.zheng@xxxxxxxxx>
Signed-off-by: Aaron Lu <aaron.lu@xxxxxxxxx>
---
drivers/ata/libata-acpi.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/ata/libata-acpi.c b/drivers/ata/libata-acpi.c
index f6d80e3..87f2f39 100644
--- a/drivers/ata/libata-acpi.c
+++ b/drivers/ata/libata-acpi.c
@@ -77,7 +77,7 @@ acpi_handle ata_dev_acpi_handle(struct ata_device *dev)
acpi_integer adr;
struct ata_port *ap = dev->link->ap;
- if (dev->flags & ATA_DFLAG_ACPI_DISABLED)
+ if (libata_noacpi || dev->flags & ATA_DFLAG_ACPI_DISABLED)
return NULL;
if (ap->flags & ATA_FLAG_ACPI_SATA) {
@@ -1047,7 +1047,7 @@ static int compat_pci_ata(struct ata_port *ap)
static int ata_acpi_bind_host(struct ata_port *ap, acpi_handle *handle)
{
- if (ap->flags & ATA_FLAG_ACPI_SATA)
+ if (libata_noacpi || ap->flags & ATA_FLAG_ACPI_SATA)
return -ENODEV;
*handle = acpi_get_child(DEVICE_ACPI_HANDLE(ap->tdev.parent),
--
1.8.2.1.94.g173f9a7
--
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