This was found when using pwm-led on am33xx and enable
heartbeat trigger.

[  808.624876] =================================
[  808.629443] [ INFO: inconsistent lock state ]
[  808.634021] 3.9.0 #2 Not tainted
[  808.637415] ---------------------------------
[  808.641981] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
[  808.648288] swapper/0 [HC0[0]:SC1[1]:HE1:SE0] takes:
[  808.653494]  (prepare_lock){+.?.+.}, at: [<c027c211>] clk_unprepare+0x15/0x24
[  808.661040] {SOFTIRQ-ON-W} state was registered at:
[  808.666155]   [<c004ec4d>] __lock_acquire+0x411/0x824
[  808.671465]   [<c004f359>] lock_acquire+0x41/0x50
[  808.676412]   [<c039ee9d>] mutex_lock_nested+0x31/0x1d8
[  808.681912]   [<c027c275>] clk_prepare+0x15/0x28
[  808.686764]   [<c0590c6b>] _init+0x117/0x1e0
[  808.691256]   [<c0019ef9>] omap_hwmod_for_each+0x29/0x3c
[  808.696842]   [<c0591107>] __omap_hwmod_setup_all+0x17/0x2c
[  808.702696]   [<c0008653>] do_one_initcall+0xc3/0x10c
[  808.708017]   [<c058a627>] kernel_init_freeable+0xa7/0x134
[  808.713778]   [<c039a543>] kernel_init+0x7/0x98
[  808.718544]   [<c000cd95>] ret_from_fork+0x11/0x3c
[  808.723583] irq event stamp: 1379172
[  808.727328] hardirqs last  enabled at (1379172): [<c03a0759>] _raw_spin_unlock_irqrestore+0x21/0x30
[  808.736828] hardirqs last disabled at (1379171): [<c03a03c3>] _raw_spin_lock_irqsave+0x13/0x38
[  808.745876] softirqs last  enabled at (1379164): [<c002ae5d>] irq_enter+0x49/0x4c
[  808.753747] softirqs last disabled at (1379165): [<c002aec3>] irq_exit+0x63/0x88
[  808.761518]
[  808.761518] other info that might help us debug this:
[  808.768373]  Possible unsafe locking scenario:
[  808.768373]
[  808.774578]        CPU0
[  808.777141]        ----
[  808.779705]   lock(prepare_lock);
[  808.783186]   <Interrupt>
[  808.785929]     lock(prepare_lock);
[  808.789595]
[  808.789595]  *** DEADLOCK ***
[  808.789595]
[  808.795805] 1 lock held by swapper/0:
[  808.799643]  #0:  (((&heartbeat_data->timer))){+.-...}, at: [<c002e204>] call_timer_fn+0x0/0x90
[  808.808814]
[  808.808814] stack backtrace:
[  808.813402] [<c000ff19>] (unwind_backtrace+0x1/0x98) from [<c039bd75>] (print_usage_bug.part.25+0x16d/0x1cc)
[  808.823721] [<c039bd75>] (print_usage_bug.part.25+0x16d/0x1cc) from [<c004e595>] (mark_lock+0x18d/0x434)
[  808.833669] [<c004e595>] (mark_lock+0x18d/0x434) from [<c004ec1d>] (__lock_acquire+0x3e1/0x824)
[  808.842803] [<c004ec1d>] (__lock_acquire+0x3e1/0x824) from [<c004f359>] (lock_acquire+0x41/0x50)
[  808.852031] [<c004f359>] (lock_acquire+0x41/0x50) from [<c039ee9d>] (mutex_lock_nested+0x31/0x1d8)
[  808.861433] [<c039ee9d>] (mutex_lock_nested+0x31/0x1d8) from [<c027c211>] (clk_unprepare+0x15/0x24)
[  808.870930] [<c027c211>] (clk_unprepare+0x15/0x24) from [<c019f7bf>] (ehrpwm_pwm_disable+0x5f/0x80)
[  808.880431] [<c019f7bf>] (ehrpwm_pwm_disable+0x5f/0x80) from [<c019f29f>] (pwm_disable+0x27/0x28)
[  808.889751] [<c019f29f>] (pwm_disable+0x27/0x28) from [<c026f8f3>] (led_heartbeat_function+0x3f/0xb0)
[  808.899431] [<c026f8f3>] (led_heartbeat_function+0x3f/0xb0) from [<c002e249>] (call_timer_fn+0x45/0x90)
[  808.909288] [<c002e249>] (call_timer_fn+0x45/0x90) from [<c002e399>] (run_timer_softirq+0x105/0x17c)
[  808.918884] [<c002e399>] (run_timer_softirq+0x105/0x17c) from [<c002abc5>] (__do_softirq+0xa5/0x150)
[  808.928486] [<c002abc5>] (__do_softirq+0xa5/0x150) from [<c002aec3>] (irq_exit+0x63/0x88)
[  808.937098] [<c002aec3>] (irq_exit+0x63/0x88) from [<c000d599>] (handle_IRQ+0x21/0x54)
[  808.945415] [<c000d599>] (handle_IRQ+0x21/0x54) from [<c0008495>] (omap3_intc_handle_irq+0x5d/0x68)
[  808.954900] [<c0008495>] (omap3_intc_handle_irq+0x5d/0x68) from [<c000c7ff>] (__irq_svc+0x3f/0x64)
[  808.964287] Exception stack(0xc05b1f68 to 0xc05b1fb0)
[  808.969587] 1f60:                   00000001 00000001 00000000 00000000 c05b0000 c0619748
[  808.978158] 1f80: c05b0000 c05b0000 c0619748 413fc082 00000000 00000000 01000000 c05b1fb0
[  808.986719] 1fa0: c004f989 c000d6f0 400f0033 ffffffff
[  808.992024] [<c000c7ff>] (__irq_svc+0x3f/0x64) from [<c000d6f0>] (cpu_idle+0x60/0x98)
[  809.000250] [<c000d6f0>] (cpu_idle+0x60/0x98) from [<c058a535>] (start_kernel+0x1e9/0x234)

Remove non atomic clk api calls and use only atomic for enable/disable because
can be called from atomic context (led_heartbeat_function is timer callback).
Signed-off-by: NMarek Belisko <marek.belisko@streamunlimited.com>
Signed-off-by: NThierry Reding <thierry.reding@gmail.com>

devm_ioremap_resource does sanity checks on the given resource. No need to
duplicate this in the driver.
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>
Acked-by: NStephen Warren <swarren@nvidia.com>

Both ehrpwm_pwm_save_context() and ehrpwm_pwm_restore_context() are only used in
this file, make them static.
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Signed-off-by: NThierry Reding <thierry.reding@avionic-design.de>

This patch adds CONFIG_PM_SLEEP to suspend/resume functions to fix
the following build warning when CONFIG_PM_SLEEP is not selected.

drivers/pwm/pwm-tiehrpwm.c:562:12: warning: 'ehrpwm_pwm_suspend' defined but not used [-Wunused-function]
drivers/pwm/pwm-tiehrpwm.c:580:12: warning: 'ehrpwm_pwm_resume' defined but not used [-Wunused-function
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NThierry Reding <thierry.reding@avionic-design.de>

Convert all uses of devm_request_and_ioremap() to the newly introduced
devm_ioremap_resource() which provides more consistent error handling.
Signed-off-by: NThierry Reding <thierry.reding@avionic-design.de>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

In low power modes of AM33XX platforms, peripherals power is cut off.
This patch supports low power sleep transition support for EHRPWM
driver.
Signed-off-by: NPhilip Avinash <avinashphilip@ti.com>
Signed-off-by: NThierry Reding <thierry.reding@avionic-design.de>

The clock framework has changed and it's now better to invoke
clock_prepare_enable() and clk_disable_unprepare() rather than the
legacy clk_enable() and clk_disable() calls. This patch converts the
pwm-tiehrpwm driver to the new framework.
Signed-off-by: NPhilip Avinash <avinashphilip@ti.com>
Signed-off-by: NThierry Reding <thierry.reding@avionic-design.de>

CONFIG_HOTPLUG is going away as an option so __devexit is no
longer needed.
Signed-off-by: NBill Pemberton <wfp5p@virginia.edu>
Acked-by: NThierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

CONFIG_HOTPLUG is going away as an option so __devinit is no longer
needed.
Signed-off-by: NBill Pemberton <wfp5p@virginia.edu>
Acked-by: NThierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

CONFIG_HOTPLUG is going away as an option so __devexit_p is no longer
needed.
Signed-off-by: NBill Pemberton <wfp5p@virginia.edu>
Acked-by: NThierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Enable pinctrl for pwm-tiehrpwm if pinctrl driver available, else
bail out with warning message.
Signed-off-by: NPhilip, Avinash <avinashphilip@ti.com>
Signed-off-by: NThierry Reding <thierry.reding@avionic-design.de>

This patch
1. Add support for device-tree binding for EHRWPM driver.
2. Set size of pwm-cells set to 3 to support PWM channel number, PWM
   period & polarity configuration from device tree.
3. Add enable/disable clock gating in PWM subsystem common config space.
4. When here set .owner member in platform_driver structure to
   THIS_MODULE.
Signed-off-by: NPhilip, Avinash <avinashphilip@ti.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Rob Landley <rob@landley.net>
Signed-off-by: NThierry Reding <thierry.reding@avionic-design.de>

Some platforms (like AM33XX) requires clock gating from control module
explicitly for TBCLK. Enabling of this clock required for the
functioning of the time base sub module in EHRPWM module. Adding support
for handling by enabling the clock on PWM device enable & disable on PWM
device disable. Platforms don't have explicit TBCLK gating has to add
dummy TBCLK node.
Signed-off-by: NPhilip, Avinash <avinashphilip@ti.com>
Signed-off-by: NThierry Reding <thierry.reding@avionic-design.de>

Make sure the duty-cycle and period passed in are not negative. This
should eventually be made implicit by making them unsigned. While at
it, the drivers' .config() implementations can have the equivalent
checks removed.
Signed-off-by: NThierry Reding <thierry.reding@avionic-design.de>
Cc: Shawn Guo <shawn.guo@linaro.org>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Sachin Kamat <sachin.kamat@linaro.org>
Cc: Axel Lin <axel.lin@gmail.com>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Cc: Jingoo Han <jg1.han@samsung.com>
Cc: Jonghwan Choi <jhbird.choi@samsung.com>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: "Philip, Avinash" <avinashphilip@ti.com>
Cc: Vaibhav Bedia <vaibhav.bedia@ti.com>
Acked-by: NJingoo Han <jg1.han@samsung.com>

EHRPWM hardware supports polarity configuration of PWM output. However
configuration of polarity done in hardware only in .enable() to ensure
PWM output present only after enabling PWM. This commit adds support for
polarity configuration for EHRPWM.
When being here, remove configuring of polarity during .config() and do
it explicitly from .set_polarity().
Signed-off-by: NPhilip, Avinash <avinashphilip@ti.com>
Signed-off-by: NThierry Reding <thierry.reding@avionic-design.de>

EHRPWM hardware supports 2 independent PWM channels. However the device
uses only one register to handle period setting for both channels. So
both channels should be configured for same period (in nsec).

Fix the same by returning error for conflicting period values.

However, allow
1. Configuration of period settings if not conflicting with other
channels
2. Re-configuring of period settings if no other channels being
configured
Signed-off-by: NPhilip, Avinash <avinashphilip@ti.com>
Signed-off-by: NThierry Reding <thierry.reding@avionic-design.de>

The implementation in devm_request_and_ioremap() already shows error message,
so no need to show dev_err again if devm_request_and_ioremap() fails.
Signed-off-by: NAxel Lin <axel.lin@gmail.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Philip, Avinash <avinashphilip@ti.com>
Signed-off-by: NThierry Reding <thierry.reding@avionic-design.de>

Enhanced high resolution PWM module (EHRPWM) hardware can be used to
generate PWM output over 2 channels. This commit adds PWM driver support
for EHRPWM device present on AM33XX SOC. Current implementation supports
simple PWM functionality.
Reviewed-by: NVaibhav Bedia <vaibhav.bedia@ti.com>
Signed-off-by: NPhilip, Avinash <avinashphilip@ti.com>
Signed-off-by: NThierry Reding <thierry.reding@avionic-design.de>