Re: [PATCH v3 1/2] gpio: gpiolib: Generalise state persistence beyond sleep

From: Rob Herring
Date: Wed Nov 01 2017 - 20:15:40 EST


On Wed, Nov 01, 2017 at 03:04:56PM +1100, Andrew Jeffery wrote:
> General support for state persistence is added to gpiolib with the
> introduction of a new pinconf parameter to propagate the request to
> hardware. The existing persistence support for sleep is adapted to
> include hardware support if the GPIO driver provides it. Persistence
> continues to be enabled by default; in-kernel consumers can opt out, but
> userspace (currently) does not have a choice.
>
> The *_SLEEP_MAY_LOSE_VALUE and *_SLEEP_MAINTAIN_VALUE symbols are
> renamed, dropping the SLEEP prefix to reflect that the concept is no
> longer sleep-specific. I feel that renaming to just *_MAY_LOSE_VALUE
> could initially be misinterpreted, so I've further changed the symbols
> to *_TRANSITORY and *_PERSISTENT to address this.
>
> The sysfs interface is modified only to keep consistency with the
> chardev interface in enforcing persistence for userspace exports.
>
> Signed-off-by: Andrew Jeffery <andrew@xxxxxxxx>
> ---
> drivers/gpio/gpiolib-of.c | 6 ++--
> drivers/gpio/gpiolib-sysfs.c | 14 +++++---
> drivers/gpio/gpiolib.c | 61 ++++++++++++++++++++++++++++++---
> drivers/gpio/gpiolib.h | 2 +-

> include/dt-bindings/gpio/gpio.h | 6 ++--

Acked-by: Rob Herring <robh@xxxxxxxxxx>

> include/linux/gpio/consumer.h | 8 +++++
> include/linux/gpio/machine.h | 4 +--
> include/linux/of_gpio.h | 2 +-
> include/linux/pinctrl/pinconf-generic.h | 2 ++
> 9 files changed, 87 insertions(+), 18 deletions(-)