Commit Graph

22 Commits

Author SHA1 Message Date
Wolfram Sang
faed9c3808 pwm: don't use devm_pinctrl_get_select_default() in probe
Since commit ab78029 (drivers/pinctrl: grab default handles from device core),
we can rely on device core for setting the default pins. Compile tested only.

Acked-by: Linus Walleij <linus.walleij@linaro.org> (personally at LCE13)
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-10-15 12:16:35 +02:00
Jingoo Han
ac872bc9ed pwm: tiehrpwm: add missing __iomem annotation
Fix the following sparse warnings:

drivers/pwm/pwm-tiehrpwm.c:144:16: warning: incorrect type in argument 1 (different address spaces)
drivers/pwm/pwm-tiehrpwm.c:144:16:    expected void const volatile [noderef] <asn:2>*addr
drivers/pwm/pwm-tiehrpwm.c:144:16:    got void *
drivers/pwm/pwm-tiehrpwm.c:149:9: warning: incorrect type in argument 2 (different address spaces)
drivers/pwm/pwm-tiehrpwm.c:149:9:    expected void volatile [noderef] <asn:2>*addr
drivers/pwm/pwm-tiehrpwm.c:149:9:    got void *
drivers/pwm/pwm-tiehrpwm.c:157:18: warning: incorrect type in argument 1 (different address spaces)
drivers/pwm/pwm-tiehrpwm.c:157:18:    expected void const volatile [noderef] <asn:2>*addr
drivers/pwm/pwm-tiehrpwm.c:157:18:    got void *
drivers/pwm/pwm-tiehrpwm.c:160:9: warning: incorrect type in argument 2 (different address spaces)
drivers/pwm/pwm-tiehrpwm.c:160:9:    expected void volatile [noderef] <asn:2>*addr
drivers/pwm/pwm-tiehrpwm.c:160:9:    got void *

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-09-03 13:09:16 +02:00
Marek Belisko
b388f15fd1 pwm: pwm-tiehrpwm: Use clk_enable/disable instead clk_prepare/unprepare.
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: Marek Belisko <marek.belisko@streamunlimited.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-26 23:23:54 +02:00
Wolfram Sang
362e9cd2f5 drivers/pwm: don't check resource with devm_ioremap_resource
devm_ioremap_resource does sanity checks on the given resource. No need to
duplicate this in the driver.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Stephen Warren <swarren@nvidia.com>
2013-05-18 11:55:58 +02:00
Axel Lin
b343a1887e pwm: tiehrpwm: Staticize non-exported symbols
Both ehrpwm_pwm_save_context() and ehrpwm_pwm_restore_context() are only used in
this file, make them static.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2013-03-26 16:04:03 +01:00
Jingoo Han
29258b215a pwm: pwm-tiehrpwm: add CONFIG_PM_SLEEP to suspend/resume functions
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: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2013-03-11 08:28:22 +01:00
Linus Torvalds
3eb05225ee pwm: Changes for v3.9-rc1
A new driver has been added to support the PWM mode of the timer counter
 blocks found on Atmel AT91 SoCs. The VT8500 driver now supports changing
 the PWM signal polarity and the TI drivers (EHRPWM and ECAP) gained
 suspend and resume functionality.
 
 User drivers can now query the core for whether access to a PWM device
 will sleep (if the PWM chip is on a slow bus such as I2C or SPI).
 
 The pwm-backlight driver now handles the backlight BL_CORE_FBBLANK state
 in addition to the FB layer's blanking states.
 
 To round things off, a few fixes and cleanups are also included.
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Merge tag 'for-3.9-rc1' of git://gitorious.org/linux-pwm/linux-pwm

Pull PWM changes from Thierry Reding:
 "A new driver has been added to support the PWM mode of the timer
  counter blocks found on Atmel AT91 SoCs.  The VT8500 driver now
  supports changing the PWM signal polarity and the TI drivers (EHRPWM
  and ECAP) gained suspend and resume functionality.

  User drivers can now query the core for whether access to a PWM device
  will sleep (if the PWM chip is on a slow bus such as I2C or SPI).

  The pwm-backlight driver now handles the backlight BL_CORE_FBBLANK
  state in addition to the FB layer's blanking states.

  To round things off, a few fixes and cleanups are also included"

* tag 'for-3.9-rc1' of git://gitorious.org/linux-pwm/linux-pwm:
  pwm: twl: Use to_twl() instead of container_of()
  pwm: tegra: assume CONFIG_OF
  pwm_backlight: Validate dft_brightness in main probe function
  pwm: Export pwm_{set,get}_chip_data()
  pwm: Make Kconfig entries more consistent
  pwm: Add can_sleep property to drivers
  pwm: Add pwm_can_sleep() as exported API to users
  pwm-backlight: handle BL_CORE_FBBLANK state
  pwm: pwm-tiecap: Low power sleep support
  pwm: pwm-tiehrpwm: Low power sleep support
  pwm: pwm-tiehrpwm: Update the clock handling of pwm-tiehrpwm driver
  pwm: vt8500: Add polarity support
  pwm: vt8500: Register write busy test performed incorrectly
  pwm: atmel: add Timer Counter Block PWM driver
2013-02-26 09:34:29 -08:00
Thierry Reding
6d4294d163 pwm: Convert to devm_ioremap_resource()
Convert all uses of devm_request_and_ioremap() to the newly introduced
devm_ioremap_resource() which provides more consistent error handling.

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-22 11:41:57 -08:00
Philip Avinash
0e2feb17de pwm: pwm-tiehrpwm: Low power sleep support
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: Philip Avinash <avinashphilip@ti.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2013-01-17 16:52:58 +01:00
Philip, Avinash
0074b49b3f pwm: pwm-tiehrpwm: Update the clock handling of pwm-tiehrpwm driver
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: Philip Avinash <avinashphilip@ti.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2013-01-14 08:12:27 +01:00
Linus Torvalds
74779e2226 pwm: Changes for v3.8-rc1
A new driver has been added for the SPEAr platform and the TWL4030/6030
 driver has been replaced by two drivers that control the regular PWMs
 and the PWM driven LEDs provided by the chips.
 
 The vt8500, tiecap, tiehrpwm, i.MX, LPC32xx and Samsung drivers have all
 been improved and the device tree bindings now support the PWM signal
 polarity.
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Merge tag 'for-3.8-rc1' of git://gitorious.org/linux-pwm/linux-pwm

Pull pwm changes from Thierry Reding:
 "A new driver has been added for the SPEAr platform and the
  TWL4030/6030 driver has been replaced by two drivers that control the
  regular PWMs and the PWM driven LEDs provided by the chips.

  The vt8500, tiecap, tiehrpwm, i.MX, LPC32xx and Samsung drivers have
  all been improved and the device tree bindings now support the PWM
  signal polarity."

Fix up trivial conflicts due to __devinit/exit removal.

* tag 'for-3.8-rc1' of git://gitorious.org/linux-pwm/linux-pwm: (21 commits)
  pwm: samsung: add missing s3c->pwm_id assignment
  pwm: lpc32xx: Set the chip base for dynamic allocation
  pwm: lpc32xx: Properly disable the clock on device removal
  pwm: lpc32xx: Fix the PWM polarity
  pwm: i.MX: eliminate build warning
  pwm: Export of_pwm_xlate_with_flags()
  pwm: Remove pwm-twl6030 driver
  pwm: New driver to support PWM driven LEDs on TWL4030/6030 series of PMICs
  pwm: New driver to support PWMs on TWL4030/6030 series of PMICs
  pwm: pwm-tiehrpwm: pinctrl support
  pwm: tiehrpwm: Add device-tree binding
  pwm: pwm-tiehrpwm: Adding TBCLK gating support.
  pwm: pwm-tiecap: pinctrl support
  pwm: tiecap: Add device-tree binding
  pwm: Add TI PWM subsystem driver
  pwm: Device tree support for PWM polarity
  pwm: vt8500: Ensure PWM clock is enabled during pwm_config
  pwm: vt8500: Fix build error
  pwm: spear: Staticize spear_pwm_config()
  pwm: Add SPEAr PWM chip driver support
  ...
2012-12-19 08:19:07 -08:00
Bill Pemberton
77f37917a6 pwm: remove use of __devexit
CONFIG_HOTPLUG is going away as an option so __devexit is no
longer needed.

Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Acked-by: Thierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-28 12:23:41 -08:00
Bill Pemberton
3e9fe83d27 pwm: remove use of __devinit
CONFIG_HOTPLUG is going away as an option so __devinit is no longer
needed.

Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Acked-by: Thierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-28 12:23:41 -08:00
Bill Pemberton
fd1091125a pwm: remove use of __devexit_p
CONFIG_HOTPLUG is going away as an option so __devexit_p is no longer
needed.

Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Acked-by: Thierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-28 12:23:41 -08:00
Philip, Avinash
98ccf49daf pwm: pwm-tiehrpwm: pinctrl support
Enable pinctrl for pwm-tiehrpwm if pinctrl driver available, else
bail out with warning message.

Signed-off-by: Philip, Avinash <avinashphilip@ti.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-11-28 15:16:18 +01:00
Philip, Avinash
53ad9e8d37 pwm: tiehrpwm: Add device-tree binding
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: Philip, 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: Thierry Reding <thierry.reding@avionic-design.de>
2012-11-28 15:16:17 +01:00
Philip, Avinash
d91861dafd pwm: pwm-tiehrpwm: Adding TBCLK gating support.
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: Philip, Avinash <avinashphilip@ti.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-11-28 15:16:16 +01:00
Thierry Reding
c2d476a98f pwm: Check for negative duty-cycle and period
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: Thierry 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: Jingoo Han <jg1.han@samsung.com>
2012-10-05 20:56:43 +02:00
Philip, Avinash
daa5629b21 pwm: pwm-tiehrpwm: Add support for configuring polarity of PWM
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: Philip, Avinash <avinashphilip@ti.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-09-10 17:05:53 +02:00
Philip, Avinash
01b2d4536f pwm: pwm-tiehrpwm: Fix conflicting channel period setting
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: Philip, Avinash <avinashphilip@ti.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-09-10 17:04:38 +02:00
Axel Lin
2ffdc9a648 pwm: Remove a redundant error message when devm_request_and_ioremap fails
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: Axel Lin <axel.lin@gmail.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Philip, Avinash <avinashphilip@ti.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-08-17 14:08:25 +02:00
Philip, Avinash
19891b20e7 pwm: pwm-tiehrpwm: PWM driver support for EHRPWM
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: Vaibhav Bedia <vaibhav.bedia@ti.com>
Signed-off-by: Philip, Avinash <avinashphilip@ti.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-07-26 07:45:20 +02:00