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authorKenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>2008-11-10 13:54:43 +0900
committerJesse Barnes <jbarnes@virtuousgeek.org>2008-11-11 13:33:05 -0800
commit2485b8674bf5762822e14e1554938e36511c0ae4 (patch)
tree9594d7366d234f9b23c33da9b087c120562b0070 /drivers/pci
parentf21f237cf55494c3a4209de323281a3b0528da10 (diff)
downloadlinux-2485b8674bf5762822e14e1554938e36511c0ae4.tar.bz2
PCI: ignore bit0 of _OSC return code
Currently acpi_run_osc() checks all the bits in _OSC result code (the first DWORD in the capabilities buffer) to see error condition. But the bit 0, which doesn't indicate any error, must be ignored. The bit 0 is used as the query flag at _OSC invocation time. Some platforms clear it during _OSC evaluation, but the others don't. On latter platforms, current acpi_run_osc() mis-detects error when _OSC is evaluated with query flag set because it doesn't ignore the bit 0. Because of this, the __acpi_query_osc() always fails on such platforms. And this is the cause of the problem that pci_osc_control_set() doesn't work since the commit 4e39432f4df544d3dfe4fc90a22d87de64d15815 which changed pci_osc_control_set() to use __acpi_query_osc(). Tested-by:"Tomasz Czernecki <czernecki@gmail.com> Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Diffstat (limited to 'drivers/pci')
-rw-r--r--drivers/pci/pci-acpi.c15
1 files changed, 8 insertions, 7 deletions
diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c
index b3a63edb6901..ae5ec76dca77 100644
--- a/drivers/pci/pci-acpi.c
+++ b/drivers/pci/pci-acpi.c
@@ -63,7 +63,7 @@ static acpi_status acpi_run_osc(acpi_handle handle,
union acpi_object in_params[4];
struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
union acpi_object *out_obj;
- u32 osc_dw0, flags = osc_args->capbuf[OSC_QUERY_TYPE];
+ u32 errors, flags = osc_args->capbuf[OSC_QUERY_TYPE];
/* Setting up input parameters */
input.count = 4;
@@ -92,15 +92,16 @@ static acpi_status acpi_run_osc(acpi_handle handle,
status = AE_TYPE;
goto out_kfree;
}
- osc_dw0 = *((u32 *)out_obj->buffer.pointer);
- if (osc_dw0) {
- if (osc_dw0 & OSC_REQUEST_ERROR)
+ /* Need to ignore the bit0 in result code */
+ errors = *((u32 *)out_obj->buffer.pointer) & ~(1 << 0);
+ if (errors) {
+ if (errors & OSC_REQUEST_ERROR)
printk(KERN_DEBUG "_OSC request fails\n");
- if (osc_dw0 & OSC_INVALID_UUID_ERROR)
+ if (errors & OSC_INVALID_UUID_ERROR)
printk(KERN_DEBUG "_OSC invalid UUID\n");
- if (osc_dw0 & OSC_INVALID_REVISION_ERROR)
+ if (errors & OSC_INVALID_REVISION_ERROR)
printk(KERN_DEBUG "_OSC invalid revision\n");
- if (osc_dw0 & OSC_CAPABILITIES_MASK_ERROR) {
+ if (errors & OSC_CAPABILITIES_MASK_ERROR) {
if (flags & OSC_QUERY_ENABLE)
goto out_success;
printk(KERN_DEBUG "_OSC FW not grant req. control\n");