tree ba3b74d202a655a9a68fafb8ca1cffcc66101bbe
parent bd1dbc3b9d20f9fe43d7b06848fc821bc88124c3
author Alexandre Courbot <acourbot@nvidia.com> 1414570394 +0900
committer Linus Walleij <linus.walleij@linaro.org> 1414683707 +0100

Documentation: gpio: guidelines for bindings

Now that ACPI supports named GPIO properties, either through ACPI 5.1 or
the per-driver ACPI GPIO mappings, we can be more narrow about the way
GPIOs should be specified in Device Tree bindings.

This patch updates the GPIO DT bindings documentation to highlight the
following rules for new GPIO bindings:

- All new bindings must have a meaningful name (e.g. the "gpios"
  property must not be used)
- The only suffix allowed is "-gpios", no matter the number of
  descriptors in the property
- GPIOs can only be grouped under the same property when they serve the
  same purpose, a case that should remain exceptional (e.g. bit-banged
  data lines).

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>