[PATCH] ARM: drivers/amba: release the resource to allow for deferred probe

[Dinh Nguyen]

With commit "79bdcb202a35 ARM: 8906/1: drivers/amba: add reset control to
amba bus probe", the amba bus driver needs to be deferred probe because the
reset driver is probed later than the amba bus. However with a deferred
probe, the call to request_resource() in the driver returns -EBUSY. The
reason is the driver has not released the resource from the previous probe
attempt.

This patch releases the resource when amba_device_try_add() returns
-EPROBE_DEFER. This allows the deferred probe to continue.

Fixes: 79bdcb202a35 ("ARM: 8906/1: drivers/amba: add reset control to
amba bus probe")
Signed-off-by: Dinh Nguyen <dingu...@kernel.org>
---
 drivers/amba/bus.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/amba/bus.c b/drivers/amba/bus.c
index f39f075abff9..f246b847c991 100644
--- a/drivers/amba/bus.c
+++ b/drivers/amba/bus.c
@@ -535,6 +535,7 @@ int amba_device_add(struct amba_device *dev, struct 
resource *parent)
 
        if (ret == -EPROBE_DEFER) {
                struct deferred_device *ddev;
+               release_resource(&dev->res);
 
                ddev = kmalloc(sizeof(*ddev), GFP_KERNEL);
                if (!ddev)
-- 
2.20.0