From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Gleixner Subject: Re: [PATCH 1/2] gpiolib: Add possibility to mask which GPIOs are added to IRQ domain Date: Thu, 15 Sep 2016 20:50:31 +0200 (CEST) Message-ID: References: <20160915155210.94413-1-mika.westerberg@linux.intel.com> <57DAC75E.5080203@arm.com> <20160915181244.GI1811@lahna.fi.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Return-path: In-Reply-To: <20160915181244.GI1811@lahna.fi.intel.com> Sender: linux-kernel-owner@vger.kernel.org To: Mika Westerberg Cc: Marc Zyngier , Linus Walleij , Phidias Chiang , Anisse Astier , Heikki Krogerus , Yu C Chen , linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-gpio@vger.kernel.org On Thu, 15 Sep 2016, Mika Westerberg wrote: > On Thu, Sep 15, 2016 at 05:07:58PM +0100, Marc Zyngier wrote: > > Mika, > > > > On 15/09/16 16:52, Mika Westerberg wrote: > > > When using GPIO irqchip helpers to setup irqchip for a gpiolib based > > > driver, it is not possible to select which GPIOs to add to the IRQ domain. > > > Instead it just adds all GPIOs which is not always desired. For example > > > there might be GPIOs that for some reason just cannot be used as interrupts > > > at all. > > > > > > To make this possible we add valid_mask to each gpio_chip and by default > > > assume all GPIOs can be used as interrupts. Drivers can then tune this > > > using clear_bit() or similar before they call gpiochip_irqchip_add(). > > > > > > Suggested-by: Linus Walleij > > > Signed-off-by: Mika Westerberg > > > --- > > > drivers/gpio/gpiolib.c | 32 +++++++++++++++++++++++++++++--- > > > include/linux/gpio/driver.h | 1 + > > > 2 files changed, 30 insertions(+), 3 deletions(-) > > > > > > diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c > > > index 53ff25ac66d8..d84c23b47f44 100644 > > > --- a/drivers/gpio/gpiolib.c > > > +++ b/drivers/gpio/gpiolib.c > > > @@ -1186,6 +1186,18 @@ int gpiochip_add_data(struct gpio_chip *chip, void *data) > > > if (status) > > > goto err_remove_chip; > > > } > > > + > > > +#ifdef CONFIG_GPIOLIB_IRQCHIP > > > + chip->valid_mask = kcalloc(BITS_TO_LONGS(chip->ngpio), sizeof(long), > > > + GFP_KERNEL); > > > > Do we really want to make this a mandatory thing? In most cases, I'd > > expect this valid_mask to have all bits set, so you might as well not > > allocate it at all in that case (and only allocate it if you actually > > need it). > > We can make drivers to allocate it and only if set use it in core. Make it a flag in gpio_chip which allocates it here when requested so we don't end up with driver writers getting the alloc/free/error handling wrong over and over. Thanks, tglx