[PATCH v2 0/4] ARM: S5P: Support gpio interrupts

[Marek Szyprowski]

Hello,

On Wednesday, June 23, 2010 9:51 AM Kukjin Kim wrote:

> Joonyoung Shim wrote:
> >
> > This patch v2 set is to support gpio interrupts of samsung s5p cpus, and
> > the GPIOlib gpio_to_irq goes to plat-samsung gpiolib, so patch v2 set
> > has four commit smaller than v1.
> >
> > Changes since v1:
> > - Add irq_base to s3c_gpio_chip struct
> > - GPIOlib gpio_to_irq() is implemented to samsung_gpiolib_to_irq() of
> >   plat-samsung gpiolib
> >
> > Joonyoung Shim (4):
> >       ARM: S5PV210: Add gpio interrupt support
> >       ARM: S5PC100: Use S5P gpio interrupts interface
> >       ARM: S5PC100: Move external interrupt defines
> >       ARM: SAMSUNG: Add GPIOlib gpio_to_irq
> >
> >  arch/arm/mach-s5pc100/Makefile                 |    2 +-
> >  arch/arm/mach-s5pc100/gpiolib.c                |   70 ++-----
> >  arch/arm/mach-s5pc100/include/mach/gpio.h      |    7 -
> >  arch/arm/mach-s5pc100/include/mach/irqs.h      |   18 ++-
> >  arch/arm/mach-s5pc100/include/mach/regs-gpio.h |    7 +
> >  arch/arm/mach-s5pc100/irq-gpio.c               |  266
> ------------------------
> >  arch/arm/mach-s5pv210/gpiolib.c                |   18 ++-
> >  arch/arm/mach-s5pv210/include/mach/irqs.h      |   16 ++-
> >  arch/arm/plat-s5p/Makefile                     |    2 +-
> >  arch/arm/plat-s5p/irq-gpioint.c                |  208 ++++++++++++++++++
> >  arch/arm/plat-samsung/gpiolib.c                |    9 +
> >  arch/arm/plat-samsung/include/plat/gpio-core.h |    6 +
> >  12 files changed, 295 insertions(+), 334 deletions(-)
> >  delete mode 100644 arch/arm/mach-s5pc100/irq-gpio.c
> >  create mode 100644 arch/arm/plat-s5p/irq-gpioint.c
> >
> 
> I am sure this patchset is working code, but Ben had made suggestion about
> 'sparse irq'...
> It is because there are too many gpio interrupts and having support of all
> of them is unnecessary as realistically only few of them maybe used.

Right. Ben suggested to create a pool for gpio interrupts (for example 16
interrupts) and selectively assign them in machine startup code to those
gpio pins that really need it.

The problem is that such solution is not yet ready and we really need the
gpio interrupt functionality for our boards (Aquila and GONI). 

Maybe these current patches could be merged now, and then, once the new
solution is prepared, the gpio interrupt support get converted to selective
registering?

S5PC100 already has gpio interrupt support.
 
> In fact in SMDK board there is no use of gpio in interrupt mode.

We are talking about support for Samsung S5PV210/S5PC110 SoCs in the Linux
mainline kernel, not the support for only SMDK boards. GPIO interrupts is
a feature of the SoC not a particular board.

Best regards
--
Marek Szyprowski
Samsung Poland R&D Center