I also found the similar topic at mail list : 1. [PATCH] ACPI: return first _ADR match for acpi_get_child http://www.spinics.net/lists/linux-acpi/msg39739.html 2.ACPI: Rework acpi_get_child() to be more efficient" has been added to the 3.8-stable tree http://www.spinics.net/lists/stable/msg03621.html 2013/5/21 <jeff.wu@xxxxxxx>: > From: Jeff Wu <zlinuxkernel@xxxxxxxxx> > > Once do_acpi_find_child() found the first matching handle, it makes the acpi_get_child() > loop stop and return the matching handle. But, at some of the platforms, a "_ADR" is > with the multiple devices, and if one is enabled, the others will be disabled. > Just like a case: > Address : 0x1FFFF ; handle : SB_PCI0.SATA.DEV0 > Address : 0x1FFFF ; handle : SB_PCI0.SATA.DEV1 > Address : 0x1FFFF ; handle : SB_PCI0.SATA.DEV2 > > If DEV0 and DEV1 are disabled and DEV2 is enabled, the target is to get DEV2 handle, but > actually it always return the first disabled device DEV0 handle. So add a _STA evaluating > at do_acpi_find_child() to check the device status. If the object exists, but it is disabled, > acpi_get_child() will continue looping to get the correct handle that the object exists and > is enabled. > > > Signed-off-by: Jeff Wu <zlinuxkernel@xxxxxxxxx> > --- > drivers/acpi/glue.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/drivers/acpi/glue.c b/drivers/acpi/glue.c > index 40a84cc..ace6c2e 100644 > --- a/drivers/acpi/glue.c > +++ b/drivers/acpi/glue.c > @@ -81,11 +81,14 @@ static struct acpi_bus_type *acpi_get_bus_type(struct device *dev) > static acpi_status do_acpi_find_child(acpi_handle handle, u32 lvl_not_used, > void *addr_p, void **ret_p) > { > - unsigned long long addr; > acpi_status status; > + unsigned long long addr = 0, sta = 0; > > status = acpi_evaluate_integer(handle, METHOD_NAME__ADR, NULL, &addr); > if (ACPI_SUCCESS(status) && addr == *((u64 *)addr_p)) { > + status = acpi_bus_get_status_handle(handle, &sta); > + if (ACPI_SUCCESS(status) && !(sta & ACPI_STA_DEVICE_ENABLED)) > + return AE_CTRL_DEPTH; > *ret_p = handle; > return AE_CTRL_TERMINATE; > } > -- > 1.8.1.2 > > -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
