GPIOs can be also used on bcm53xx, however this arch requires different
implementation of IRQ support. It uses different IRQ number (117) and
different masks & acking.
Signed-off-by: NRafał Miłecki <zajec5@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

I've here a device detected as:
bcma: bus0: Found chip with id 0xD144, rev 0x01 and package 0x08
I couldn't find GPIO handling hw button until trying GPIO 20. It seems
BCM53572 also has 32 GPIOs.
Signed-off-by: NRafał Miłecki <zajec5@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Some Broadcom boards have more GPIOs available. For example Linksys
E3200 home router is based on SoC id 0x5357, package 0x0A and uses GPIO
23 to reset internal USB WiFi (gpio23=wombo_reset).
Signed-off-by: NRafał Miłecki <zajec5@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Signed-off-by: NRafał Miłecki <zajec5@gmail.com>
Signed-off-by: NJohn Crispin <blogic@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/6343/

With this patch we prevent the irq from being fired when it is
registered. The Hardware fires an IRQ when input signal XOR polarity
AND gpio mask is 1. Now we are setting polarity to a vlaue so that is
is 0 when we register it.

In addition we also set the irq mask register to 0 when the irq handler
is initialized, so all gpio irqs are masked and there will be no
unexpected irq.
Signed-off-by: NHauke Mehrtens <hauke@hauke-m.de>
Tested-by: NRafał Miłecki <zajec5@gmail.com>
Signed-off-by: NJohn Crispin <blogic@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/6304/

Input GPIO changes can generate interrupts, but we need kind of ACK for
them by changing IRQ polarity. This is required to stop hardware from
keep generating interrupts and generate another one on the next GPIO
state change.
This code allows using GPIOs with standard interrupts and add for
example GPIO buttons support.
Signed-off-by: NRafał Miłecki <zajec5@gmail.com>
Acked-by: NHauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: NJohn Crispin <blogic@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/6216/

This patch unregisters the gpio chip before bcma gets unloaded.
Signed-off-by: NHauke Mehrtens <hauke@hauke-m.de>
Reported-by: NPiotr Haber <phaber@broadcom.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The old bcm47xx gpio code had support for gpio_to_irq, but the new
code did not provide this function, but returned -ENXIO all the time.
This patch adds the missing function.
Signed-off-by: NHauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Register a GPIO driver to access the GPIOs provided by the chip.
The GPIOs of the SoC should always start at 0 and the other GPIOs could
start at a random position. There is just one SoC in a system and when
they start at 0 the number is predictable.
Signed-off-by: NHauke Mehrtens <hauke@hauke-m.de>
Patchwork: http://patchwork.linux-mips.org/patch/4587Acked-by: NFlorian Fainelli <florian@openwrt.org>