[PATCH] gpio: of_get_named_gpio_flags() return -EPROBE_DEFER if GPIO not yet available
From: Stephen Warren <hidden>
Date: 2012-06-18 02:06:35
Also in:
linux-mmc, lkml
From: Stephen Warren <hidden>
Date: 2012-06-18 02:06:35
Also in:
linux-mmc, lkml
On 06/17/2012 04:11 AM, Roland Stigge wrote:
of_get_named_gpio_flags() and of_get_named_gpio() return -EPROBE_DEFER if the respective GPIO is not (yet) available. This is useful if driver's probe() functions try to get a GPIO whose controller isn't probed yet. Thus, the driver can be probed again later on. The function still returns -EINVAL on other errors (parse error or node doesn't exist). This way, the case of an optional/intentionally missing GPIO is handled appropriately.
While I agree this is a correct change, it is going to break some
existing code - at least sound/soc/tegra/tegra_{wm8903.c,alc5632.c}. I'm
happy to send patches for those files though (is this going into 3.5 or
3.6?). However, have you audited all existing callers (including
indirect, e.g. through plain of_get_named_gpio()) for issues this will
cause?