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. 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 fixes how we handle the condition of EPROBE_DEFER that is returned from getting the reset controls. For this condition, the patch will jump to defer_probe, which will iounmap, dev_pm_domain_detach, and release the resource. Fixes: 79bdcb202a35 ("ARM: 8906/1: drivers/amba: add reset control to amba bus probe") Signed-off-by: Dinh Nguyen <dingu...@kernel.org> --- v3: jump to defer_probe where the driver will unmap and pm_detach the driver resource for the next probe attempt v2: release the resource when of_reset_control_array_get_optional_shared() returns EPROBE_DEFER --- drivers/amba/bus.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/amba/bus.c b/drivers/amba/bus.c index f39f075abff9..4a021b1dab3d 100644 --- a/drivers/amba/bus.c +++ b/drivers/amba/bus.c @@ -409,9 +409,12 @@ static int amba_device_try_add(struct amba_device *dev, struct resource *parent) */ rstc = of_reset_control_array_get_optional_shared(dev->dev.of_node); if (IS_ERR(rstc)) { - if (PTR_ERR(rstc) != -EPROBE_DEFER) + ret = PTR_ERR(rstc); + if (ret == -EPROBE_DEFER) + goto defer_probe; + else dev_err(&dev->dev, "Can't get amba reset!\n"); - return PTR_ERR(rstc); + return ret; } reset_control_deassert(rstc); reset_control_put(rstc); @@ -448,6 +451,7 @@ static int amba_device_try_add(struct amba_device *dev, struct resource *parent) ret = -ENODEV; } + defer_probe: iounmap(tmp); dev_pm_domain_detach(&dev->dev, true); -- 2.20.0