| Message ID | 20191002123349.23771-1-dinguyen@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [PATCHv2] ARM: drivers/amba: release the resource to allow for deferred probe | expand |
On Wed, Oct 02, 2019 at 07:33:49AM -0500, Dinh Nguyen wrote: > 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 err_release, which will release the resource. > > Fixes: 79bdcb202a35 ("ARM: 8906/1: drivers/amba: add reset control to > amba bus probe") > Signed-off-by: Dinh Nguyen <dinguyen@kernel.org> > --- > v2: release the resource when of_reset_control_array_get_optional_shared() > returns EPROBE_DEFER > --- > drivers/amba/bus.c | 7 +++++-- > 1 file changed, 5 insertions(+), 2 deletions(-) > > diff --git a/drivers/amba/bus.c b/drivers/amba/bus.c > index f39f075abff9..1109437815eb 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 err_release; > + else > dev_err(&dev->dev, "Can't get amba reset!\n"); > - return PTR_ERR(rstc); > + return ret; Still a negative. Remember in the comments to the previous patch I talked about ioremap(). Please read the code that you are modifying and carefully consider what needs to happen at this site to properly clean up on failure.
diff --git a/drivers/amba/bus.c b/drivers/amba/bus.c index f39f075abff9..1109437815eb 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 err_release; + 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);
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 err_release, which will release the resource. Fixes: 79bdcb202a35 ("ARM: 8906/1: drivers/amba: add reset control to amba bus probe") Signed-off-by: Dinh Nguyen <dinguyen@kernel.org> --- v2: release the resource when of_reset_control_array_get_optional_shared() returns EPROBE_DEFER --- drivers/amba/bus.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)