The Rockchip GPIO interrupt controller totally throws away all status
about an interrupt when you "disable" the interrupt.  That has
unfortunate consequences in the following situation:

1. An edge-triggered interrupt is enabled and should wake the system.
2. System suspend happens: interrupt is disabled and marked for wake.
3. rockchip_irq_suspend() reenables the interrupt so we can wake.
4. Interrupt happens when asleep.
5. rockchip_irq_resume() redisables the interrupt.
6. Disabling the interrupt throws away all status about it.
7. Normal system resume happens and we enable the interrupt again,
   since we threw away status about the interrupt we don't know it
   fired while suspended.  Even worse: if we need both edges of the
   interrupt the logic to swap edges never runs.

Note: even if we somehow can post the status about wakeup interrupts
in rockchip_irq_resume() we would still have a window of losing any
edges that came in while interrupts were disabled.

If we use mask only then we don't need to worry.  The GPIO Interrupt
controller keeps track of pending interrupts that are enabled and just
masked.

There was no real strong reason to support the enable/disable
functionality (other than that it seemed right), so let's go back to
just supporting mask/unmask but actually map it to the real
mask/unmask.  This ends up with slightly different (and more correct)
behavior than before (f2dd028 pinctrl: rockchip: Fix
enable/disable/mask/unmask).

Signed-off-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Linux 3.19-rc6

I was seeing cases where I was losing interrupts when inserting and
removing SD cards.  Sometimes the card would get "stuck" in the
inserted state.

I believe that the problem was related to the code to handle the case
where we needed both rising and falling edges.  This code would
disable the interrupt as the polarity was switched.  If an interrupt
came at the wrong time it could be lost.

We'll match what the gpio-dwapb.c driver does upstream and change the
interrupt polarity without disabling things.

Signed-off-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Additionally to the generic DT parameters, allow drivers to provide
driver-specific DT parameters to be used with the generic parser
infrastructure.

To achieve this 'struct pinctrl_desc' is extended to pass custom pinconf
option to the core. In order to pass this kind of information, the
related data structures - 'struct pinconf_generic_dt_params',
'pin_config_item' - are moved from pinconf internals to the
pinconf-generic header.

Additionally pinconfg-generic is refactored to not only iterate over the
generic pinconf parameters but also take the parameters into account
that are provided through the driver's 'struct pinctrl_desc'.
In particular 'pinconf_generic_parse_dt_config()' and
'pinconf_generic_dump' helpers are split into two parts each. In order
to have a more generic helper that can be used to process the generic
parameters as well as the driver-specific ones.

v2:
 - fix typo
 - add missing documentation for @conf_items member in struct
 - rebase to pinctrl/devel: conflict in abx500
 - rename _pinconf_generic_dump() to pinconf_generic_dump_one()
 - removed '_' from _parse_dt_cfg()
 - removed BUG_ONs, error condition is handled in if statements
 - removed pinconf_generic_dump_group() & pinconf_generic_dump_pin
   helpers
   - fixed up corresponding call sites
   - renamed pinconf_generic_dump() to pinconf_generic_dump_pins()
   - added kernel-doc to pinconf_generic_dump_pins()
 - add kernel-doc
 - more verbose commit message

Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
Tested-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

The Rockchip pinctrl driver was only implementing the "mask" and
"unmask" operations though the hardware actually has two distinct
things: enable/disable and mask/unmask.  It was implementing the
"mask" operations as a hardware enable/disable and always leaving all
interrupts unmasked.

I believe that the old system had some downsides, specifically:
- (Untested) if an interrupt went off while interrupts were "masked"
  it would be lost.  Now it will be kept track of.
- If someone wanted to change an interrupt back into a GPIO (is such a
  thing sensible?) by calling irq_disable() it wouldn't actually take
  effect.  That's because Linux does some extra optimizations when
  there's no true "disable" function: it does a lazy mask.

Let's actually implement enable/disable/mask/unmask properly.

Signed-off-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

The rockchip pinctrl driver was using irq_gc_set_wake() as its
implementation of irq_set_wake() but was totally ignoring everything
that irq_gc_set_wake() did (which is to upkeep gc->wake_active).

Let's fix that by setting gc->wake_active as GPIO_INTEN at suspend
time and restoring GPIO_INTEN at resume time.

NOTE a few quirks when thinking about this patch:
- Rockchip pinctrl hardware supports both "disable/enable" and
  "mask/unmask".  Right now we only use "disable/enable" and present
  those to Linux as "mask/unmask".  This should be OK because
  enable/disable is optional and Linux will implement it in terms of
  mask/unmask.  At the moment we always tell hardware all interrupts
  are unmasked (the boot default).
- At suspend time Linux tries to call "disable" on all interrupts and
  also enables wakeup on all wakeup interrupts.  One would think that
  since "disable" is implemented as "mask" when "disable" isn't
  provided and that since we were ignoring gc->wake_active that
  nothing would have woken us up.  That's not the case since Linux
  "optimizes" things and just leaves interrutps unmasked, assuming it
  could mask them later when they go off.  That meant that at suspend
  time all interrupts were actually being left enabled.

With this patch random non-wakeup interrupts no longer wake the system
up.  Wakeup interrupts still wake the system up.

Signed-off-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Pull driver core update from Greg KH:
 "Here's the set of driver core patches for 3.19-rc1.

  They are dominated by the removal of the .owner field in platform
  drivers.  They touch a lot of files, but they are "simple" changes,
  just removing a line in a structure.

  Other than that, a few minor driver core and debugfs changes.  There
  are some ath9k patches coming in through this tree that have been
  acked by the wireless maintainers as they relied on the debugfs
  changes.

  Everything has been in linux-next for a while"

* tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (324 commits)
  Revert "ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries"
  fs: debugfs: add forward declaration for struct device type
  firmware class: Deletion of an unnecessary check before the function call "vunmap"
  firmware loader: fix hung task warning dump
  devcoredump: provide a one-way disable function
  device: Add dev_<level>_once variants
  ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries
  ath: use seq_file api for ath9k debugfs files
  debugfs: add helper function to create device related seq_file
  drivers/base: cacheinfo: remove noisy error boot message
  Revert "core: platform: add warning if driver has no owner"
  drivers: base: support cpu cache information interface to userspace via sysfs
  drivers: base: add cpu_device_create to support per-cpu devices
  topology: replace custom attribute macros with standard DEVICE_ATTR*
  cpumask: factor out show_cpumap into separate helper function
  driver core: Fix unbalanced device reference in drivers_probe
  driver core: fix race with userland in device_add()
  sysfs/kernfs: make read requests on pre-alloc files use the buffer.
  sysfs/kernfs: allow attributes to request write buffer be pre-allocated.
  fs: sysfs: return EGBIG on write if offset is larger than file size
  ...

Save and restore the gpio6_c6 pinmux setting, since Maskrom of RK3288
would modify it to sdmmc0_det, so it need to be restored to the correct
setting after resume from Maskrom.

Signed-off-by: Chris Zhong <zyw@rock-chips.com>
Tested-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>

support suspend/resume of pinctrl, it allows handling sleep mode
for hogged pins in pinctrl

Signed-off-by: Chris Zhong <zyw@rock-chips.com>
Tested-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>

There were a few instances where the rockchip pinctrl driver would do
read-modify-write with no spinlock.  Add a spinlock for these cases.

Signed-off-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>