Date: Mon, 10 Feb 2014 12:05:44 +0200
From: Mika Westerberg <mika.westerberg@linux.intel.com>
To: Alexandre Courbot <acourbot@nvidia.com>
Cc: Linus Walleij <linus.walleij@linaro.org>,
        Jean-Jacques Hiblot <jjhiblot@traphandler.com>,
        linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/2] gpiolib: add gpiochip_get_desc() driver function
Message-ID: <20140210100544.GU18029@intel.com>
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On Sun, Feb 09, 2014 at 05:43:54PM +0900, Alexandre Courbot wrote:
> Some drivers dealing with a gpio_chip might need to act on its
> descriptors directly; one example is pinctrl drivers that need to lock a
> GPIO for being used as IRQ using gpiod_lock_as_irq().
> 
> This patch exports a gpiochip_get_desc() function that returns the
> GPIO descriptor at the requested index. It also sweeps the
> gpio_to_chip() function out of the consumer interface since any holder
> of a gpio_chip reference can manipulate its GPIOs way beyond what a
> consumer should be allowed to do.
> 
> As a result, gpio_chip is not visible anymore to simple GPIO consumers.
> 
> Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
> ---
> Jean-Jacques, I think you will want to use this function for locking GPIOs
> in the AT91 pinctrl driver. Mika, we talked about this a while ago already,
> but here it is finally. Next patch uses it in the GPIO ACPI driver.

This seems to be useful for ACPI GPIO operation region implementation as
well.

Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
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