This function can be more easily tested if it is in the uclass.

Signed-off-by: Simon Glass <sjg@chromium.org>

Add helpers to the uclass to allow finding out the pin function.

Signed-off-by: Simon Glass <sjg@chromium.org>

We have several GPIO drivers now and all are doing similar things to record
which GPIOs are reserved.

Move this logic into the uclass to make the drivers similar.

We retain the request()/free() methods since currently one driver does use
these for setting up the pin.

Signed-off-by: Simon Glass <sjg@chromium.org>

At present banks must be named and it is not possible to refer to GPIOs by
number in driver model. Some boards use numbering - e.g. OMAP. It is fairly
easy to support by detecting the absense of a bank name (which starts with
a letter).

Add support for numbered GPIOs in addition to the existing bank support.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@ti.com>

We want 'N0' and 'n0' to mean the same thing, so ensure that case is not
considered when naming GPIO banks.

Signed-off-by: Simon Glass <sjg@chromium.org>

using UBI and DM together leads in compiler error, as
both define a "struct device", so rename "struct device"
in include/dm/device.h to "struct udevice", as we use
linux code (MTD/UBI/UBIFS some USB code,...) and cannot
change the linux "struct device"

Signed-off-by: Heiko Schocher <hs@denx.de>
Cc: Simon Glass <sjg@chromium.org>
Cc: Marek Vasut <marex@denx.de>

Add driver model support for GPIOs. Since existing GPIO drivers do not use
driver model, this feature must be enabled by CONFIG_DM_GPIO. After all
GPO drivers are converted over we can perhaps remove this config.

Tests are provided for the sandbox implementation, and are a sufficient
sanity check for basic operation.

The GPIO uclass understands the concept of named banks of GPIOs, with each
GPIO device providing a single bank. Within each bank the GPIOs are numbered
using an offset from 0 to n-1. For example a bank named 'b' with 20
offsets will provide GPIOs named b0 to b19.

Anonymous GPIO banks are also supported, and are just numbered without any
prefix.

Each time a GPIO driver is added to the uclass, the GPIOs are renumbered
accordinging, so there is always a global GPIO numbering order.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Marek Vasut <marex@denx.de>
Signed-off-by: Pavel Herrmann <morpheus.ibis@gmail.com>
Signed-off-by: Viktor Křivák <viktor.krivak@gmail.com>
Signed-off-by: Tomas Hlavacek <tmshlvck@gmail.com>