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Revision bd8733738c5af6114dd15d340b3f8713e9b624c2 authored by Boris Brezillon on 08 February 2015, 18:23:42 UTC, committed by Linus Walleij on 18 March 2015, 01:01:36 UTC 
pinctrl: at91: move lock/unlock_as_irq calls into request/release
 
The gpiochip_lock_as_irq call can fail and return an error,
while the irq_startup is not expected to fail (returns an
unsigned int which is not checked by irq core code).

irq_request/release_resources functions have been created
to address this problem.

Move gpiochip_lock/unlock_as_irq calls into
irq_request/release_resources functions to prevent using a
gpio as an irq if the gpiochip_lock_as_irq call failed.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
1 parent 549e783
Raw File
dynamic-resolution-notes.txt 
Device Tree Dynamic Resolver Notes
----------------------------------

This document describes the implementation of the in-kernel
Device Tree resolver, residing in drivers/of/resolver.c and is a
companion document to Documentation/devicetree/dt-object-internal.txt[1]

How the resolver works
----------------------

The resolver is given as an input an arbitrary tree compiled with the
proper dtc option and having a /plugin/ tag. This generates the
appropriate __fixups__ & __local_fixups__ nodes as described in [1].

In sequence the resolver works by the following steps:

1. Get the maximum device tree phandle value from the live tree + 1.
2. Adjust all the local phandles of the tree to resolve by that amount.
3. Using the __local__fixups__ node information adjust all local references
   by the same amount.
4. For each property in the __fixups__ node locate the node it references
   in the live tree. This is the label used to tag the node.
5. Retrieve the phandle of the target of the fixup.
6. For each fixup in the property locate the node:property:offset location
   and replace it with the phandle value.
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