2013/5/22 Jeff Wu [off-list ref]:

2013/5/21 Lan Tianyu [off-list ref]:

quoted

2013/5/21  [off-list ref]:

quoted

From: Jeff Wu <redacted>

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 <redacted>
---
 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;

Will this affect other devices? Since the device maybe disabled during
do binding with ACPI.
After some operations, the device would be enabled.

At our platforms, DEV1 use for win8,DEV2 use for win7,DEV1 use for Linux.
If these devices are disabled when do init, they will always be
disabled ,so, work fine.

At some of the platforms, the devices may be disabled during do the
first binding ,if their status are changed,do they not do re-binding ?

Currently, the glue binding operation takes place when the device  is
created. In my mind, there is no re-binding operation after the device being
created, Unless the device being removed and created again.

quoted

Hi Rafael:
                 How about add a new function
"acpi_get_children_with_same_addr" to return a list
which contains all these child devices with same _ADR.And then do some
special check in the specific
bus glue callback. Since these cases are no common.

quoted

                *ret_p = handle;
                return AE_CTRL_TERMINATE;
        }
--
1.8.1.2


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--
Best regards
Tianyu Lan

-- 
Best regards
Tianyu Lan