[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <500D632B.3000206@gmail.com>
Date: Mon, 23 Jul 2012 16:43:55 +0200
From: Daniel Mack <zonque@...il.com>
To: Daniel Mack <zonque@...il.com>
CC: linux-kernel@...r.kernel.org,
Grant Likely <grant.likely@...retlab.ca>,
Linus Walleij <linus.walleij@...ricsson.com>,
Arnd Bergmann <arnd@...db.de>
Subject: Re: [PATCH] gpiolib: fix chip->base handling in of_gpio_simple_xlate()
(Cc: Arnd)
On 22.07.2012 19:10, Daniel Mack wrote:
> of_gpio_simple_xlate() is called for each chip when a GPIO is looked up.
> When registering several chips off the same DT node (with different pin
> offsets) however, the lookup fails as the GPIO number passed in to
> of_gpio_simple_xlate() is likely higher than the chip's ->ngpio value.
>
> Fix that by taking into account the chip's ->base value, and return the
> relative offset of the pin inside the chip.
>
> Signed-off-by: Daniel Mack <zonque@...il.com>
> Cc: Grant Likely <grant.likely@...retlab.ca>
> Cc: Linus Walleij <linus.walleij@...ricsson.com>
> ---
>
> I'm currently porting the PXA pieces over to DT, and stumbled over what
> looks like an obvious bug to me. Correct me if I'm mistaken, but I see
> no reason why one shouldn't be able to instanciate several GPIO chips
> from a single DT node.
>
> Thanks,
> Daniel
>
> drivers/gpio/gpiolib-of.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c
> index d18068a..51bc232 100644
> --- a/drivers/gpio/gpiolib-of.c
> +++ b/drivers/gpio/gpiolib-of.c
> @@ -147,13 +147,13 @@ int of_gpio_simple_xlate(struct gpio_chip *gc,
> if (WARN_ON(gpiospec->args_count < gc->of_gpio_n_cells))
> return -EINVAL;
>
> - if (gpiospec->args[0] >= gc->ngpio)
> + if (gpiospec->args[0] >= gc->ngpio + gc->base)
> return -EINVAL;
>
> if (flags)
> *flags = gpiospec->args[1];
>
> - return gpiospec->args[0];
> + return gpiospec->args[0] - gc->base;
> }
> EXPORT_SYMBOL(of_gpio_simple_xlate);
>
>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists