tree 188e0eb7c0e09ebe5eda090df9570c5a7348816f
parent 03d152d5582abc8a1c19cb107164c3724bbd4be4
author Alexandre Courbot <acourbot@nvidia.com> 1380909597 -0700
committer Linus Walleij <linus.walleij@linaro.org> 1381501913 +0200

gpiolib: safer implementation of desc_to_gpio()

The current implementation of desc_to_gpio() relies on the chip pointer
to be set to a valid value in order to compute the GPIO number. This
was done in the hope that we can get rid of the gpio_desc global array,
but this is not happening anytime soon.

This patch reimplements desc_to_gpio() in a fashion similar to that of
gpio_to_desc(). As a result, desc_to_gpio(gpio_to_desc(gpio)) == gpio is
now always true. This allows to call desc_to_gpio() on non-initialized
descriptors as some error-handling code currently does.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Reported-by: Dr. H. Nikolaus Schaller <hns@goldelico.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>