[PATCH v7 REPOST 00/24] gpio/omap: driver cleanup and fixes

[Tarun Kanti DebBarma]

This series is continuation of cleanup of OMAP GPIO driver and fixes.
The cleanup include getting rid of cpu_is_* checks wherever possible,
use of gpio_bank list instead of static array, use of unique platform
specific value associated data member to OMAP platforms to avoid
cpu_is_* checks. The series also include PM runtime support.*

Baseline: git://gitorious.org/khilman/linux-omap-pm.git
Branch: for_3.2/gpio-cleanup
Commit: 8323374

REPOST
- Fixed debounce clock handling in
  [PATCH v7 18/26] gpio/omap: optimize suspend and resume functions
- Remove [PATCH v7 20/26] gpio/omap: skip operations in runtime callbacks
  The bank->mod_usage check in this patch is not needed any more because
  they are now already being taken care in suspend/resume and Idle paths.
- Remove [PATCH v7 26/26] gpio/omap: add dbclk aliases for all gpio modules
  This is already taken care in hwmod.
- Remove redundant blank line in
  [PATCH v7 14/26] gpio/omap: remove unnecessary bit-masking for read access

-               if (cpu_is_omap15xx() && (bank->method == METHOD_MPUIO))
-                       isr &= 0x0000ffff;

                if (bank->level_mask)
                        level_mask = bank->level_mask & enabled;

Test Details:
- Compile tested for omap1_defconfig and omap2plus_defconfig.
- OMAP1710-H3: Bootup test.
- OMAP2430/SDP, OMAP3430/SDP, OMAP4430/SDP: Functional testing.
- PM Testing on OMAP3430-SDP: retention, off_mode, system_wide
  suspend and gpio wakeup.

v7:
- Use pm_runtime_put() instead of pm_runtime_put_sync_suspend()

- Keep *_runtime_get/put*()  outside spinlock

- Remove additional checking of conditions in _restore_context()
  From:
  if (bank->regs->set_dataout && bank->regs->clear_dataout)
  ...
  To:
  if (bank->regs->set_dataout)
  ...

- Use SET_RUNTIME_PM_OPS and SET_SYSTEM_SLEEP_PM_OPS macros

- In [PATCH 19/25] gpio/omap: cleanup prepare_for_idle and resume_after_idle,
  protect the bank data elements and register access using spinlock in
  runtime_suspend/resume() callbacks.
  This is because these callbacks run with interrupts enabled.

- Add dbclk aliases for all GPIO modules. Without this, GPIO modules were not
  getting the correct clock handle to enable/disable debounec clock.

- Fix log comments on the following patches:
  [PATCH 19/25] gpio/omap: cleanup prepare_for_idle and resume_after_idle
  [PATCH 20/25] gpio/omap: skip operations in runtime callbacks
  [PATCH 24/25] gpio/omap: restore OE only after setting the output level

v6:
- Save and restore debounce registers for proper driver operation.
- Restore interrupt enable after all configuration to avoid spurious interrupts.
- Restore dataout register before oe register.
- Restore dataout into dataout_set or dataout based upon the OMAP version.
- Change register name from wkup_status to wkup_en.
- Remove wrapper around omap_pm_get_dev_context_loss_count(). Use it directly.
  Also, changed the signature of get_context_loss_count in pdata and bank structure
  from int to u32.

- Use 'context' instead of 'ctx' for clarity wherever it is used.
- Merged two patches into one which are related to bank_is_mpuio() modification.
- Use shift operator instead of following:
+       .irqctrl        = OMAP_MPUIO_GPIO_INT_EDGE / 2,

- Remove redundant check from the following
+       if (bank_is_mpuio(bank)) {
+               if (bank->regs->wkup_status) <--- redundant check
+                       mpuio_init(bank);

- Change subject of following patch
  [PATCH v5 15/22] gpio/omap: use readl in irq_handler for all access
  into
  [PATCH 14/25] gpio/omap: remove unnecessary bit-masking for read access

- Fix multi-line comments in
  [PATCH v5 20/22] gpio/omap: cleanup prepare_for_idle and resume_after_idle

v5:
- Reduce runtime callback overhead when *_get/put_sync() called from probe()
  and *_gpio_request/free().

- Dynamic context save within functions where context is modified instead of
  saving all context within a common function.

- Removed call to mpuio_init() from omap_gpio_mod_init(). Both the functions are
  called once during initialization in *_gpio_probe().
  Call to omap_gpio_mod_init() has been removed from omap_gpio_request() on the
  first access to gpio bank. One time initialization looks sufficient.

- In *_gpio_irq_handler() use *_put_sync_suspend() instead of *_put_sync().

- Removed hardcoding of OMAP16xx sysconfig register value and instead defined an
  associated constant.

- Removed *_get_sync() call from *_gpio_suspend() and *_put_sync() call from
  *_gpio_resume(). They got wrongly slipped into the code.

- Removed following redundant zero allocated initialization from mach-omap2/gpio.c
+       pdata->regs->irqctrl = 0;
+       pdata->regs->edgectrl1 = 0;
+       pdata->regs->edgectrl2 = 0;

- Removed following redundant code in gpio-omap.c
  -#define bank_is_mpuio(bank)  ((bank)->method == METHOD_MPUIO)

v4:
- since all accesses to registers are 4-byte aligned, removing special
  checks and handling of 16 and 32-bit wide bank registers and instead
  use 32-bit read/write access consistently.

- redundant usage of MOD_REG_BIT has been corrected and replaced with
  _gpio_rmw().

- omap_gpio_mod_init() function has been simplified further using _gpio_rmw().

- sysconfig register offset specific to omap16xx has been removed along
  with its usage.

- additional logic to skip from suspend/resume:

  if (!bank->regs->wkup_status || !bank->suspend_wakeup)
        return 0;

  if (!bank->regs->wkup_status || !bank->saved_wakeup)
        return 0;

- separated mpuio related changes into a different patch from the patch where
  wakeup status register related changes are done.

- Incorrect replacement of !cpu_class_is_omap2() in gpio_irq_type()
  corrected:
+       if (!bank->regs->leveldetect0 &&
+               (type & (IRQ_TYPE_LEVEL_LOW|IRQ_TYPE_LEVEL_HIGH)))
                return -EINVAL;

v3:
- Avoid use of wkup_set and wkup_clear registers. Instead use wkup_status
  register for all platforms. This is because on OMAP4 it is recommended
  not to use them.

- Remove duplicate code in omap_gpio_mod_init() for handling the same for
  32-bit and 16-bit GPIO bank widths. This is accomplished by having two
  functions to handle each case while assiging a common function pointer
  during initialization.

- Remove OMAP16xx specific one time initialization from omap_gpio_mod_init().
  Move it inside omap16xx_gpio_init().

- Avoid usage of USHRT_MAX to indicate undefined values. Use 0 instead.

- In omap_gpio_suspend()/resume() functions remove code that checks
  if the feature is supported. Instead, assign these functions to
  struct platform_driver's suspend & resume function pointers for those
  OMAP platforms whcih support this feature.

- Remove 'suspend_support' flag because it is redundant. Instead use
  wkup_* registers to decode the same information.

- Restore context also when we don't know if the context is lost.

- Make omap_gpio_save_context() and omap_gpio_restore_context()
  static.

v2:
- Do special handling of non-wakeup GPIOs only on OMAP2420. Avoid this
  handling on OMAP3430.
- Isolate cleanups and fixes into separate set of patches. Keep the cleanup
  first followed by the fixes.
- Avoid calling omap_gpio_get_context_loss() directly and instead call it
  through function pointer in pdata initialized during init.
- workaround_enabled flag is not longer needed and is removed.
- Call pwrdm_post_transition() before calling omap_gpio_resume_after_idle().
- In omap2_gpio_resume_after_idle() do context restore before handling
  workaround.
- Use PM runtime framework.
- Modify register offset names to : wkup_status, wkup_clear, wkup_set.
  Also use 'base + offset' for readibility in all relevant places.
- Remove unwanted messages from commit section like TODO, etc.

Charulatha V (10):
  gpio/omap: remove dependency on gpio_bank_count
  gpio/omap: use flag to identify wakeup domain
  gpio/omap: make gpio_context part of gpio_bank structure
  gpio/omap: fix pwrdm_post_transition call sequence
  gpio/omap: handle save/restore context in GPIO driver
  gpio/omap: make non-wakeup GPIO part of pdata
  gpio/omap: avoid cpu checks during module ena/disable
  gpio/omap: use pinctrl offset instead of macro
  gpio/omap: remove bank->method & METHOD_* macros
  gpio/omap: fix bankwidth for OMAP7xx MPUIO

Nishanth Menon (4):
  gpio/omap: save and restore debounce registers
  gpio/omap: enable irq at the end of all configuration in restore
  gpio/omap: restore OE only after setting the output level
  gpio/omap: handle set_dataout reg capable IP on restore

Tarun Kanti DebBarma (10):
  gpio/omap: further cleanup using wkup_en register
  gpio/omap: use level/edge detect reg offsets
  gpio/omap: remove hardcoded offsets in context save/restore
  gpio/omap: cleanup set_gpio_triggering function
  gpio/omap: cleanup omap_gpio_mod_init function
  gpio/omap: remove unnecessary bit-masking for read access
  gpio/omap: use pm-runtime framework
  gpio/omap: optimize suspend and resume functions
  gpio/omap: cleanup prepare_for_idle and resume_after_idle
  gpio/omap: remove omap_gpio_save_context overhead

 arch/arm/mach-omap1/gpio15xx.c         |    7 +-
 arch/arm/mach-omap1/gpio16xx.c         |   47 ++-
 arch/arm/mach-omap1/gpio7xx.c          |   14 +-
 arch/arm/mach-omap2/gpio.c             |   36 +-
 arch/arm/mach-omap2/pm34xx.c           |   21 +-
 arch/arm/plat-omap/include/plat/gpio.h |   29 +-
 drivers/gpio/gpio-omap.c               | 1049 +++++++++++++-------------------
 7 files changed, 511 insertions(+), 692 deletions(-)