Re: [PATCH] gpio: dwapb: Add support for 32 interrupts
From: Rob Herring
Date: Mon Apr 09 2018 - 15:20:22 EST
On Wed, Mar 28, 2018 at 03:22:30PM +0100, Phil Edworthy wrote:
> The DesignWare GPIO IP can be configured for either 1 or 32 interrupts,
> but the driver currently only supports 1 interrupt. See the DesignWare
> DW_apb_gpio Databook description of the 'GPIO_INTR_IO' parameter.
Someday h/w designers will realize this does nothing to optimize
interrupt handling...
> This change allows the driver to work with up to 32 interrupts, it will
> get as many interrupts as specified in the DT 'interrupts' property.
> It doesn't do anything clever with the different interrupts, it just calls
> the same handler used for single interrupt hardware.
>
> Signed-off-by: Phil Edworthy <phil.edworthy@xxxxxxxxxxx>
> ---
> Note: There are a few lines over 80 chars, but this is just guidance, right?
> Especially as there are already some lines over 80 chars.
Code, yes, but not for paragraphs of text in DT bindings.
> ---
> .../devicetree/bindings/gpio/snps-dwapb-gpio.txt | 10 ++++-
> drivers/gpio/gpio-dwapb.c | 44 +++++++++++++++++-----
> include/linux/platform_data/gpio-dwapb.h | 3 +-
> 3 files changed, 45 insertions(+), 12 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/gpio/snps-dwapb-gpio.txt b/Documentation/devicetree/bindings/gpio/snps-dwapb-gpio.txt
> index 4a75da7..e343581 100644
> --- a/Documentation/devicetree/bindings/gpio/snps-dwapb-gpio.txt
> +++ b/Documentation/devicetree/bindings/gpio/snps-dwapb-gpio.txt
> @@ -26,8 +26,14 @@ controller.
> the second encodes the triger flags encoded as described in
> Documentation/devicetree/bindings/interrupt-controller/interrupts.txt
> - interrupt-parent : The parent interrupt controller.
> -- interrupts : The interrupt to the parent controller raised when GPIOs
> - generate the interrupts.
> +- interrupts : The interrupts to the parent controller raised when GPIOs
> + generate the interrupts. If the controller provides one combined interrupt
> + for all GPIOs, specify a single interrupt. If the controller provides one
> + interrupt for each GPIO, provide a list of interrupts that correspond to each
> + of the GPIO pins. When specifying multiple interrupts, if any of the GPIOs are
> + not connected to an interrupt, use the interrupt-mask property.
> +- interrupt-mask : a 32-bit bit mask that specifies which interrupts in the list
> + of interrupts is valid, bit is 1 for a valid irq.
This is not a standard property and would need a vendor prefix. However,
I'd prefer you just skip any not connected interrupts with an invalid
interrupt number. Then the GPIO number is the index into "interrupts".
> - snps,nr-gpios : The number of pins in the port, a single cell.
This BTW should be deprecated to use "nr-gpios" instead, but that's
another patch.
> - resets : Reset line for the controller.
>