Use devm_* managed functions, so that slot-gpio users do not have to
call mmc_gpio_free_ro/cd to free up resources requested in
mmc_gpio_request_ro/cd.
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Acked-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NChris Ball <cjb@laptop.org>

The slot-gpio API provides a generic card-detection handler. To support a
wider range of hosts it has to call the host's card-event callback, if
implemented. Also increase the debounce interval to 200ms to match the
SDHCI driver.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Reviewed-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NChris Ball <cjb@laptop.org>

mmc_gpio_request_ro() doesn't store the requested gpio in ctx->ro_gpio.
As a result, subsequent calls to mmc_gpio_get_ro() will always fail
with -ENOSYS because the gpio number isn't available to that function.

Cc: stable <stable@vger.kernel.org>
Acked-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NChris Ball <cjb@laptop.org>

Card Write-Protect pin is often implemented, using a GPIO, which makes
it simple to provide a generic handler for it.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NChris Ball <cjb@laptop.org>

This prepares for the addition of further slot functions.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NChris Ball <cjb@laptop.org>

A simple extension of mmc slot functions add support for CD GPIO polling
for cases where the GPIO cannot produce interrupts, or where this is not
desired for some reason.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NChris Ball <cjb@laptop.org>

struct mmc_host::hotplug is becoming a generic hook for slot functions.
Rename it accordingly.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NChris Ball <cjb@laptop.org>

GPIOs can be used in MMC/SD-card slots not only for hotplug detection, but
also to implement the write-protection pin. Rename cd-gpio helpers to
slot-gpio to make addition of further slot GPIO functions possible.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NChris Ball <cjb@laptop.org>

Fix a boot regression on Mackerel boards with sh_mobile_sdhi
in existing kernels causing:

genirq: Threaded irq requested with handler=NULL and !ONESHOT for irq XXX

caused by 1c6c6952 (genirq: Reject bogus threaded irq requests).

This is backported from Guennadi's patch:
"mmc: extend and rename cd-gpio helpers to handle more slot GPIO functions"
Reported-by: NRafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NChris Ball <cjb@laptop.org>

Do not oops, even if mmc_cd_gpio_free() is mistakenly called on a driver
cleanup path, even though a previous call to mmc_cd_gpio_request() failed.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
[stable@: please apply to 3.3-stable]
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NChris Ball <cjb@laptop.org>

Include the linux/mmc/cd-gpio.h header to pickup the prototypes
for the two exported symbols.

This quiets the sparse warnings:

warning: symbol 'mmc_cd_gpio_request' was not declared. Should it be static?
warning: symbol 'mmc_cd_gpio_free' was not declared. Should it be static?
Signed-off-by: NH Hartley Sweeten <hsweeten@visionengravers.com>
Acked-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: NVenkatraman S <svenkatr@ti.com>
Signed-off-by: NChris Ball <cjb@laptop.org>

Calculate the IRQ number, using gpio_to_irq() and use fixed flags: trigger
on both edges. This makes two out of four arguments of the
mmc_cd_gpio_request() function redundant.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NChris Ball <cjb@laptop.org>

This patch adds a primitive helper to support card hotplug detection on
platforms, where a GPIO, capable of producing interrupts, is used for
detection of card-insertion and -removal events.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NChris Ball <cjb@laptop.org>