The first three patches handle clk_get_rate() returning 0 (which might
happen for example if the CCF is disabled). The first of these was found
because this triggered a warning with clang, the two others by looking
for similar issues in other drivers. Similar patches were merged earlier
for v6.15-rc1 in commit 92b71befc3 ("Merge tag
'objtool-urgent-2025-04-01' of
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip").
The remaining three fixes address issues in the new waveform pwm API.
Now that I worked on this a bit more, the finer details and corner cases
are better understood and the code is fixed accordingly.
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Merge tag 'pwm/for-6.15-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ukleinek/linux
Pull pwm fixes from Uwe Kleine-König:
"A set of fixes for pwm core and various drivers
The first three patches handle clk_get_rate() returning 0 (which might
happen for example if the CCF is disabled). The first of these was
found because this triggered a warning with clang, the two others by
looking for similar issues in other drivers.
The remaining three fixes address issues in the new waveform pwm API.
Now that I worked on this a bit more, the finer details and corner
cases are better understood and the code is fixed accordingly"
* tag 'pwm/for-6.15-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ukleinek/linux:
pwm: axi-pwmgen: Let .round_waveform_tohw() signal when request was rounded up
pwm: stm32: Search an appropriate duty_cycle if period cannot be modified
pwm: Let pwm_set_waveform() succeed even if lowlevel driver rounded up
pwm: fsl-ftm: Handle clk_get_rate() returning 0
pwm: rcar: Improve register calculation
pwm: mediatek: Prevent divide-by-zero in pwm_mediatek_config()
The .round_waveform_tohw() is supposed to return 1 if the requested
waveform cannot be implemented by rounding down all parameters. Also
adapt the corresponding comment to better describe why the implemented
procedure is right.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Tested-by: Trevor Gamblin <tgamblin@baylibre.com>
Link: https://lore.kernel.org/r/ba451573f0218d76645f068cec78bd97802cf010.1743844730.git.u.kleine-koenig@baylibre.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
If another channel is already enabled period must not be modified. If
the requested period is smaller than this unchangable period the driver
is still supposed to search a duty_cycle according to the usual rounding
rules.
So don't set the duty_cycle to 0 but continue to determine an
appropriate value for ccr.
Fixes: deaba9cff8 ("pwm: stm32: Implementation of the waveform callbacks")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Link: https://lore.kernel.org/r/f0c50df31daa3d6069bfa8d7fb3e71fae241b026.1743844730.git.u.kleine-koenig@baylibre.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
Waveform parameters are supposed to be rounded down to the next value
possible for the hardware. However when a requested value is too small,
.round_waveform_tohw() is supposed to pick the next bigger value and
return 1. Let pwm_set_waveform() behave in the same way.
This creates consistency between pwm_set_waveform_might_sleep() with
exact=false and pwm_round_waveform_might_sleep() +
pwm_set_waveform_might_sleep() with exact=true.
The PWM_DEBUG rounding check has to be adapted to only trigger if no
uprounding happend.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Tested-by: Trevor Gamblin <tgamblin@baylibre.com>
Link: https://lore.kernel.org/r/353dc6ae31be815e41fd3df89c257127ca0d1a09.1743844730.git.u.kleine-koenig@baylibre.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
Considering that the driver doesn't enable the used clocks (and also
that clk_get_rate() returns 0 if CONFIG_HAVE_CLK is unset) better check
the return value of clk_get_rate() for being non-zero before dividing by
it.
Fixes: 3479bbd1e1 ("pwm: fsl-ftm: More relaxed permissions for updating period")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Link: https://lore.kernel.org/r/b68351a51017035651bc62ad3146afcb706874f0.1743501688.git.u.kleine-koenig@baylibre.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
There were several issues in the function rcar_pwm_set_counter():
- The u64 values period_ns and duty_ns were cast to int on function
call which might loose bits on 32 bit architectures.
Fix: Make parameters to rcar_pwm_set_counter() u64
- The algorithm divided by the result of a division which looses
precision.
Fix: Make use of mul_u64_u64_div_u64()
- The calculated values were just masked to fit the respective register
fields which again might loose bits.
Fix: Explicitly check for overlow
Implement the respective fixes.
A side effect of fixing the 2nd issue is that there is no division by 0
if clk_get_rate() returns 0.
Fixes: ed6c1476bf ("pwm: Add support for R-Car PWM Timer")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Link: https://lore.kernel.org/r/ab3dac794b2216cc1cc56d65c93dd164f8bd461b.1743501688.git.u.kleine-koenig@baylibre.com
[ukleinek: Added an explicit #include <linux/bitfield.h> to please the
0day build bot]
Link: https://lore.kernel.org/oe-kbuild-all/202504031354.VJtxScP5-lkp@intel.com/
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
With CONFIG_COMPILE_TEST && !CONFIG_HAVE_CLK, pwm_mediatek_config() has a
divide-by-zero in the following line:
do_div(resolution, clk_get_rate(pc->clk_pwms[pwm->hwpwm]));
due to the fact that the !CONFIG_HAVE_CLK version of clk_get_rate()
returns zero.
This is presumably just a theoretical problem: COMPILE_TEST overrides
the dependency on RALINK which would select COMMON_CLK. Regardless it's
a good idea to check for the error explicitly to avoid divide-by-zero.
Fixes the following warning:
drivers/pwm/pwm-mediatek.o: warning: objtool: .text: unexpected end of section
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Link: https://lore.kernel.org/r/fb56444939325cc173e752ba199abd7aeae3bf12.1742852847.git.jpoimboe@kernel.org
[ukleinek: s/CONFIG_CLK/CONFIG_HAVE_CLK/]
Fixes: caf065f8fd ("pwm: Add MediaTek PWM support")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Link: https://lore.kernel.org/r/9e78a0796acba3435553ed7db1c7965dcffa6215.1743501688.git.u.kleine-koenig@baylibre.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
Core changes:
- None really.
New drivers:
- AMD ISP411 "AMD ISP" driver.
- Exynos 2200 and 7870 SoC subdrivers.
- Sophgo RISC-V SG2042 and SG2044 subdrivers.
- Amlogic A4 subdriver.
- Rockchip RK3528 subdriver.
- Broadcom BCM21664 subdriver.
- Allwinner A523/T527 subdriver.
- Ingenic X1600 subdriver.
- Microchip SAMA7D65 subdriver, essentially a re-branded
Atmel AT91 PIO4 driver, but nowadays a Microschip SoC line.
Improvements:
- Bring in the devm_kmemdup_array() helper and use it throughout,
also bring in changes to other subsystems for this to establish
this helper.
- Support EGPIO on the Qualcomm SA8775P SoC.
- Extend EINT support in the Mediatek driver.
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Merge tag 'pinctrl-v6.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl
Pull pin control updates from Linus Walleij:
"Core changes:
- None really.
New drivers:
- AMD ISP411 "AMD ISP" driver
- Exynos 2200 and 7870 SoC subdrivers
- Sophgo RISC-V SG2042 and SG2044 subdrivers
- Amlogic A4 subdriver
- Rockchip RK3528 subdriver
- Broadcom BCM21664 subdriver
- Allwinner A523/T527 subdriver
- Ingenic X1600 subdriver
- Microchip SAMA7D65 subdriver, essentially a re-branded Atmel AT91
PIO4 driver, but nowadays a Microschip SoC line
Improvements:
- Bring in the devm_kmemdup_array() helper and use it throughout,
also bring in changes to other subsystems for this to establish
this helper
- Support EGPIO on the Qualcomm SA8775P SoC
- Extend EINT support in the Mediatek driver"
* tag 'pinctrl-v6.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (101 commits)
pinctrl: mediatek: Add EINT support for multiple addresses
pinctrl: amlogic-a4: Drop surplus semicolon
pinctrl: nuvoton: Reduce use of OF-specific APIs
pinctrl: nuvoton: Convert to use struct group_desc
pinctrl: nuvoton: Make use of struct pinfunction and PINCTRL_PINFUNCTION()
pinctrl: nuvoton: Convert to use struct pingroup and PINCTRL_PINGROUP()
pinctrl: npcm8xx: Fix incorrect struct npcm8xx_pincfg assignment
pinctrl: tegra: Fix off by one in tegra_pinctrl_get_group()
pinctrl: PINCTRL_AMDISP should depend on DRM_AMD_ISP
pinctrl: qcom: sa8775p: Enable egpio function
dt-bindings: pinctrl: qcom: Add egpio function for sa8775p
pinctrl: qcom: tlmm-test: Validate irq_enable delivers edge irqs
pinctrl: qcom: Clear latched interrupt status when changing IRQ type
dt-bindings: pinctrl: airoha: Add missing gpio-ranges property
pinctrl: bcm281xx: Add missing assignment in bcm21664_pinctrl_lock_all()
pinctrl: amd: isp411: Fix IS_ERR() vs NULL check in probe()
dt-bindings: pinctrl: at91-pio4: add microchip,sama7d65-pinctrl
pinctrl: tegra: Set SFIO mode to Mux Register
pinctrl-tegra: Restore SFSEL bit when freeing pins
pinctrl: tegra: Add descriptions for SoC data fields
...
pwm-stmpe is the only driver that cannot be built as a module. Add the
necessary boilerplate to also make this driver modular.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Link: https://lore.kernel.org/r/20250215143723.636591-2-u.kleine-koenig@baylibre.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
Back when the sifive pwm driver was added there was no symbol for sifive
SoCs yet. Today there is ARCH_SIFIVE however. Let PWM_SIFIVE depend on
that to ensure the driver is only build for platforms where there is a
chance that the hardware is available.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Link: https://lore.kernel.org/r/20250127105001.587610-2-u.kleine-koenig@baylibre.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
The pwm-clps711x driver depends on ARCH_CLPS711X || COMPILE_TEST. With
the former being an ARCH_MULTI_V4T platform, there is always OF=y when
ARCH_CLPS711X=y, so in practise clps711x_pwm_dt_ids[] is always used.
(And in the case COMPILE_TEST=y + OF=n this only increases the driver
size a bit but still compiles.)
So drop the usage of of_match_ptr().
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20250214163442.192006-2-u.kleine-koenig@baylibre.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
Platforms can have a standardized connector/expansion slot that exposes
signals like PWMs to expansion boards in an SoC agnostic way.
The support for nexus node [1] has been added to handle those cases in
commit bd6f2fd5a1 ("of: Support parsing phandle argument lists through
a nexus node"). This commit introduced of_parse_phandle_with_args_map()
to handle nexus nodes in a generic way and the gpio subsystem adopted
the support in commit c11e6f0f04 ("gpio: Support gpio nexus dt
bindings").
A nexus node allows to remap a phandle list in a consumer node through a
connector node in a generic way. With this remapping supported, the
consumer node needs to knwow only about the nexus node. Resources behind
the nexus node are decoupled by the nexus node itself.
This is particularly useful when this consumer is described in a
device-tree overlay. Indeed, to have the exact same overlay reused with
several base systems the overlay needs to known only about the connector
is going to be applied to without any knowledge of the SoC (or the
component providing the resource) available in the system.
As an example, suppose 3 PWMs connected to a connector. The connector
PWM 0 and 2 comes from the PWM 1 and 3 of the pwm-controller1. The
connector PWM 1 comes from the PWM 4 of the pwm-controller2. An
expansion device is connected to the connector and uses the connector
PMW 1.
Nexus node support in PWM allows the following description:
soc {
soc_pwm1: pwm-controller1 {
#pwm-cells = <3>;
};
soc_pwm2: pwm-controller2 {
#pwm-cells = <3>;
};
};
connector: connector {
#pwm-cells = <3>;
pwm-map = <0 0 0 &soc_pwm1 1 0 0>,
<1 0 0 &soc_pwm2 4 0 0>,
<2 0 0 &soc_pwm1 3 0 0>;
pwm-map-mask = <0xffffffff 0x0 0x0>;
pwm-map-pass-thru = <0x0 0xffffffff 0xffffffff>;
};
expansion_device {
pwms = <&connector 1 57000 0>;
};
>From the expansion device point of view, the PWM requested is the PWM 1
available at the connector regardless of the exact PWM wired to this
connector PWM 1. Thanks to nexus node remapping described at connector
node, this PWM is the PWM 4 of the pwm-controller2.
The nexus node remapping handling consists in handling #pwm-cells,
pwm-map, pwm-map-mask and pwm-map-pass-thru properties. This is already
supported by of_parse_phandle_with_args_map() thanks to its stem_name
parameter.
Add support for nexus node device-tree binding and the related remapping
in the PWM subsystem by simply using of_parse_phandle_with_args_map()
instead of of_parse_phandle_with_args().
[1] https://github.com/devicetree-org/devicetree-specification/blob/v0.4/source/chapter2-devicetree-basics.rst#nexus-nodes-and-specifier-mapping
Signed-off-by: Herve Codina <herve.codina@bootlin.com>
Link: https://lore.kernel.org/r/20250205095547.536083-3-herve.codina@bootlin.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
The PWM chip on PXA only has a single output. Back when the device tree
binding was defined it was considered a good idea to not pass the PWM
line index as is done for all other PWM types as it would be always zero
anyhow and so doesn't add any value.
However for consistency reasons it is nice when all PWMs use the same
binding. For that reason let of_pwm_single_xlate() (i.e. the function
that implements the PXA behaviour) behave in the same way as
of_pwm_xlate_with_flags() for 3 (or more) parameters. With that in
place, the pxa-pwm binding can be updated to #pwm-cells = <3> without
breaking old device trees that stick to #pwm-cells = <1>.
Reviewed-by: Herve Codina <herve.codina@bootlin.com>
Tested-by: Duje Mihanović <duje.mihanovic@skole.hr>
Reviewed-by: Daniel Mack <daniel@zonque.org>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Link: https://lore.kernel.org/r/b33a84d3f073880e94fc303cd32ebe095eb5ce46.1738842938.git.u.kleine-koenig@baylibre.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
hrtimer_setup() takes the callback function pointer as argument and
initializes the timer completely.
Replace hrtimer_init() and the open coded initialization of
hrtimer::function with the new setup mechanism.
Acked-by: Zack Rusin <zack.rusin@broadcom.com>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Link: https://lore.kernel.org/r/7b7115da84372a49e36a0ac1a5ce553129c3ce0b.1738746904.git.namcao@linutronix.de
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
Among the three files that include pwm-lpss.h only pwm-lpss.c actually
needs <linux/pwm.h>. So move the #include statement from the former to
the latter.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Reviewed-by: Andy Shevchenko <andy@kernel.org>
Link: https://lore.kernel.org/r/20250123103939.357160-2-u.kleine-koenig@baylibre.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
DEFAULT_SYMBOL_NAMESPACE must be already defined when <linux/export.h>
is included. So move the define above the include block.
With the DEFAULT_SYMBOL_NAMESPACE being defined too late, the exported
symbols end up in the default namespace. So the respective modules can
use the symbols defined in pwm-lpss.c just fine and up to now just
imported the PWM_LPSS namespace without any gain.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Here is the big set of driver core and debugfs updates for 6.14-rc1.
It's coming late in the merge cycle as there are a number of merge
conflicts with your tree now, and I wanted to make sure they were
working properly. To resolve them, look in linux-next, and I will send
the "fixup" patch as a response to the pull request.
Included in here is a bunch of driver core, PCI, OF, and platform rust
bindings (all acked by the different subsystem maintainers), hence the
merge conflict with the rust tree, and some driver core api updates to
mark things as const, which will also require some fixups due to new
stuff coming in through other trees in this merge window.
There are also a bunch of debugfs updates from Al, and there is at least
one user that does have a regression with these, but Al is working on
tracking down the fix for it. In my use (and everyone else's linux-next
use), it does not seem like a big issue at the moment.
Here's a short list of the things in here:
- driver core bindings for PCI, platform, OF, and some i/o functions.
We are almost at the "write a real driver in rust" stage now,
depending on what you want to do.
- misc device rust bindings and a sample driver to show how to use
them
- debugfs cleanups in the fs as well as the users of the fs api for
places where drivers got it wrong or were unnecessarily doing things
in complex ways.
- driver core const work, making more of the api take const * for
different parameters to make the rust bindings easier overall.
- other small fixes and updates
All of these have been in linux-next with all of the aforementioned
merge conflicts, and the one debugfs issue, which looks to be resolved
"soon".
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-6.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core and debugfs updates from Greg KH:
"Here is the big set of driver core and debugfs updates for 6.14-rc1.
Included in here is a bunch of driver core, PCI, OF, and platform rust
bindings (all acked by the different subsystem maintainers), hence the
merge conflict with the rust tree, and some driver core api updates to
mark things as const, which will also require some fixups due to new
stuff coming in through other trees in this merge window.
There are also a bunch of debugfs updates from Al, and there is at
least one user that does have a regression with these, but Al is
working on tracking down the fix for it. In my use (and everyone
else's linux-next use), it does not seem like a big issue at the
moment.
Here's a short list of the things in here:
- driver core rust bindings for PCI, platform, OF, and some i/o
functions.
We are almost at the "write a real driver in rust" stage now,
depending on what you want to do.
- misc device rust bindings and a sample driver to show how to use
them
- debugfs cleanups in the fs as well as the users of the fs api for
places where drivers got it wrong or were unnecessarily doing
things in complex ways.
- driver core const work, making more of the api take const * for
different parameters to make the rust bindings easier overall.
- other small fixes and updates
All of these have been in linux-next with all of the aforementioned
merge conflicts, and the one debugfs issue, which looks to be resolved
"soon""
* tag 'driver-core-6.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (95 commits)
rust: device: Use as_char_ptr() to avoid explicit cast
rust: device: Replace CString with CStr in property_present()
devcoredump: Constify 'struct bin_attribute'
devcoredump: Define 'struct bin_attribute' through macro
rust: device: Add property_present()
saner replacement for debugfs_rename()
orangefs-debugfs: don't mess with ->d_name
octeontx2: don't mess with ->d_parent or ->d_parent->d_name
arm_scmi: don't mess with ->d_parent->d_name
slub: don't mess with ->d_name
sof-client-ipc-flood-test: don't mess with ->d_name
qat: don't mess with ->d_name
xhci: don't mess with ->d_iname
mtu3: don't mess wiht ->d_iname
greybus/camera - stop messing with ->d_iname
mediatek: stop messing with ->d_iname
netdevsim: don't embed file_operations into your structs
b43legacy: make use of debugfs_get_aux()
b43: stop embedding struct file_operations into their objects
carl9170: stop embedding file_operations into their objects
...
Conor Dooley found and fixed a problem in the pwm-microchip-core driver
that existed since the driver's birth in v6.5-rc1. It's about a corner
case that only happens if two pwm devices of the same chip are set to
the same long period.
The other problem is about the new pwm API that currently is only
supported by two hardware drivers. The fix prevents a NULL pointer
exception if one of the new functions is called for a pwm device with a
driver that only provides the old callbacks.
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Merge tag 'pwm/for-6.14-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ukleinek/linux
Pull pwm fixes from Uwe Kleine-König:
"Two fixes.
Conor Dooley found and fixed a problem in the pwm-microchip-core
driver that existed since the driver's birth in v6.5-rc1. It's about a
corner case that only happens if two pwm devices of the same chip are
set to the same long period.
The other problem is about the new pwm API that currently is only
supported by two hardware drivers. The fix prevents a NULL pointer
exception if one of the new functions is called for a pwm device with
a driver that only provides the old callbacks"
* tag 'pwm/for-6.14-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ukleinek/linux:
pwm: Ensure callbacks exist before calling them
pwm: microchip-core: fix incorrect comparison with max period
If one of the waveform functions is called for a chip that only supports
.apply(), we want that an error code is returned and not a NULL pointer
exception.
Fixes: 6c5126c640 ("pwm: Provide new consumer API functions for waveforms")
Cc: stable@vger.kernel.org
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Tested-by: Trevor Gamblin <tgamblin@baylibre.com>
Link: https://lore.kernel.org/r/20250123172709.391349-2-u.kleine-koenig@baylibre.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
In mchp_core_pwm_apply_locked(), if hw_period_steps is equal to its max,
an error is reported and .apply fails. The max value is actually a
permitted value however, and so this check can fail where multiple
channels are enabled.
For example, the first channel to be configured requests a period that
sets hw_period_steps to the maximum value, and when a second channel
is enabled the driver reads hw_period_steps back from the hardware and
finds it to be the maximum possible value, triggering the warning on a
permitted value. The value to be avoided is 255 (PERIOD_STEPS_MAX + 1),
as that will produce undesired behaviour, so test for greater than,
rather than equal to.
Fixes: 2bf7ecf7b4 ("pwm: add microchip soft ip corePWM driver")
Cc: stable@vger.kernel.org
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20250122-pastor-fancied-0b993da2d2d2@spud
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
This time there are very little changes for pwm. There is nothing new,
just a few maintenance cleanups.
The contributors this time around were Krzysztof Kozlowski, Mingwei
Zheng, Philipp Stanner, and Stanislav Jakubek. Thanks!
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Merge tag 'pwm/for-6.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/ukleinek/linux
Pull pwm updates from Uwe Kleine-König:
"This time there are very little changes for pwm. There is nothing new,
just a few maintenance cleanups.
The contributors this time around were Krzysztof Kozlowski, Mingwei
Zheng, Philipp Stanner, and Stanislav Jakubek. Thanks!"
* tag 'pwm/for-6.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/ukleinek/linux:
pwm: stm32: Add check for clk_enable()
dt-bindings: pwm: Correct indentation and style in DTS example
pwm: stm32-lp: Add check for clk_enable()
dt-bindings: pwm: marvell,berlin-pwm: Convert from txt to yaml
dt-bindings: pwm: sprd,ums512-pwm: convert to YAML
pwm: Replace deprecated PCI functions
Add check for the return value of clk_enable() to catch the potential
error.
Fixes: 19f1016ea9 ("pwm: stm32: Fix enable count for clk in .probe()")
Signed-off-by: Mingwei Zheng <zmw12306@gmail.com>
Signed-off-by: Jiasheng Jiang <jiashengjiangcool@gmail.com>
Link: https://lore.kernel.org/r/20241215224752.220318-1-zmw12306@gmail.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
We need the debugfs / driver-core fixes in here as well for testing and
to build on top of.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Constify the following API:
struct device *device_find_child(struct device *dev, void *data,
int (*match)(struct device *dev, void *data));
To :
struct device *device_find_child(struct device *dev, const void *data,
device_match_t match);
typedef int (*device_match_t)(struct device *dev, const void *data);
with the following reasons:
- Protect caller's match data @*data which is for comparison and lookup
and the API does not actually need to modify @*data.
- Make the API's parameters (@match)() and @data have the same type as
all of other device finding APIs (bus|class|driver)_find_device().
- All kinds of existing device match functions can be directly taken
as the API's argument, they were exported by driver core.
Constify the API and adapt for various existing usages.
BTW, various subsystem changes are squashed into this commit to meet
'git bisect' requirement, and this commit has the minimal and simplest
changes to complement squashing shortcoming, and that may bring extra
code improvement.
Reviewed-by: Alison Schofield <alison.schofield@intel.com>
Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Acked-by: Uwe Kleine-König <ukleinek@kernel.org> # for drivers/pwm
Signed-off-by: Zijun Hu <quic_zijuhu@quicinc.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20241224-const_dfc_done-v5-4-6623037414d4@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fabrice Gasnier found and fixed a regression I introduced with v6.13-rc1
when converting the stm32 pwm driver to support the new waveform stuff.
On some hardware variants this completely broke the driver.
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Merge tag 'pwm/for-6.13-rc4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ukleinek/linux
Pull pwm fix from Uwe Kleine-König:
"Fix regression in pwm-stm32 driver when converting to new waveform
support
Fabrice Gasnier found and fixed a regression I introduced with
v6.13-rc1 when converting the stm32 pwm driver to support the new
waveform stuff. On some hardware variants this completely broke the
driver"
* tag 'pwm/for-6.13-rc4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ukleinek/linux:
pwm: stm32: Fix complementary output in round_waveform_tohw()
Add check for the return value of clk_enable() to catch the potential
error.
We used APP-Miner to find it.
Fixes: e70a540b4e ("pwm: Add STM32 LPTimer PWM driver")
Signed-off-by: Mingwei Zheng <zmw12306@gmail.com>
Signed-off-by: Jiasheng Jiang <jiashengjiangcool@gmail.com>
Link: https://lore.kernel.org/r/20241206215318.3402860-1-zmw12306@gmail.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
pcim_iomap_table() and pcim_request_regions() have been deprecated in
commit e354bb84a4 ("PCI: Deprecate pcim_iomap_table(),
pcim_iomap_regions_request_all()") and commit d140f80f60 ("PCI:
Deprecate pcim_iomap_regions() in favor of pcim_iomap_region()").
Replace these functions with pcim_iomap_region().
Additionally, pass the actual driver names to pcim_iomap_region()
instead of the previous pci_name(), since the 'name' parameter should
always reflect which driver owns a region.
Signed-off-by: Philipp Stanner <pstanner@redhat.com>
Link: https://lore.kernel.org/r/20241111090944.11293-2-pstanner@redhat.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
When the timer supports complementary output, the CCxNE bit must be set
additionally to the CCxE bit. So to not overwrite the latter use |=
instead of = to set the former.
Fixes: deaba9cff8 ("pwm: stm32: Implementation of the waveform callbacks")
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com>
Link: https://lore.kernel.org/r/20241217150021.2030213-1-fabrice.gasnier@foss.st.com
[ukleinek: Slightly improve commit log]
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
Commit cdd30ebb1b ("module: Convert symbol namespace to string
literal") only converted MODULE_IMPORT_NS() and EXPORT_SYMBOL_NS(),
leaving DEFAULT_SYMBOL_NAMESPACE as a macro expansion.
This commit converts DEFAULT_SYMBOL_NAMESPACE in the same way to avoid
annoyance for the default namespace as well.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Some PWM hardwares (e.g. MC33XS2410) cannot implement a zero duty cycle
but can instead disable the hardware which also results in a constant
inactive output.
There are some checks (enabled with CONFIG_PWM_DEBUG) to help
implementing a driver without violating the normal rounding rules. Make
them less strict to let above described hardware pass without warning.
Reported-by: Dimitri Fedrau <dima.fedrau@gmail.com>
Link: https://lore.kernel.org/r/20241103205215.GA509903@debian
Fixes: 3ad1f3a332 ("pwm: Implement some checks for lowlevel drivers")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Reviewed-by: Dimitri Fedrau <dima.fedrau@gmail.com>
Tested-by: Dimitri Fedrau <dima.fedrau@gmail.com>
Link: https://lore.kernel.org/r/20241105153521.1001864-2-u.kleine-koenig@baylibre.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
Export the pwm_get_state_hw() function. This is useful in cases where
we want to know what the hardware is actually doing, rather than what
what we requested it should do.
Locking had to be rearranged to ensure that the chip is still
operational before trying to access ops now that this can be called
from outside the pwm core.
Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://lore.kernel.org/r/20241029-pwm-export-pwm_get_state_hw-v2-1-03ba063a3230@baylibre.com
[ukleinek: Add dummy for !CONFIG_PWM]
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
Use the dedicated helper for comparing device names against strings.
Note, the current code has a check for the dev_name() against NULL.
With the current implementations of the device_add() and dev_set_name()
it most likely a theoretical assumption that that might happen, while
I don't see how. Hence, that check has simply been removed.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20241025142704.405340-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
Implement workaround for ERR051198
(https://www.nxp.com/docs/en/errata/IMX8MN_0N14Y.pdf)
PWM output may not function correctly if the FIFO is empty when a new SAR
value is programmed.
Description:
When the PWM FIFO is empty, a new value programmed to the PWM Sample
register (PWM_PWMSAR) will be directly applied even if the current timer
period has not expired. If the new SAMPLE value programmed in the
PWM_PWMSAR register is less than the previous value, and the PWM counter
register (PWM_PWMCNR) that contains the current COUNT value is greater
than the new programmed SAMPLE value, the current period will not flip
the level. This may result in an output pulse with a duty cycle of 100%.
Workaround:
Program the current SAMPLE value in the PWM_PWMSAR register before
updating the new duty cycle to the SAMPLE value in the PWM_PWMSAR
register. This will ensure that the new SAMPLE value is modified during
a non-empty FIFO, and can be successfully updated after the period
expires.
Write the old SAR value before updating the new duty cycle to SAR. This
avoids writing the new value into an empty FIFO.
This only resolves the issue when the PWM period is longer than 2us
(or <500kHz) because write register is not quick enough when PWM period is
very short.
Reproduce steps:
cd /sys/class/pwm/pwmchip1/pwm0
echo 2000000000 > period # It is easy to observe by using long period
echo 1000000000 > duty_cycle
echo 1 > enable
echo 8000 > duty_cycle # One full high pulse will be seen by scope
Fixes: 166091b189 ("[ARM] MXC: add pwm driver for i.MX SoCs")
Reviewed-by: Jun Li <jun.li@nxp.com>
Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
Link: https://lore.kernel.org/r/20241008194123.1943141-1-Frank.Li@nxp.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
Enable the FORCE_ALIGN flag by default in the AXI PWMGEN driver. This
flag makes the behavior of the PWM output consistent with the
description at the top of the driver file.
* Limitations:
* - The writes to registers for period and duty are shadowed until
* LOAD_CONFIG is written to AXI_PWMGEN_REG_RSTN, at which point
* they take effect.
* - Writing LOAD_CONFIG also has the effect of re-synchronizing all
* enabled channels, which could cause glitching on other channels. It
* is therefore expected that channels are assigned harmonic periods
* and all have a single user coordinating this.
Without this flag, the PWM output does not change until the period of
all PWM output channels has run out, which makes the PWM impossible to
use in some cases because it takes too long to change the output.
Signed-off-by: David Lechner <dlechner@baylibre.com>
Reviewed-by: Nuno Sa <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20241009-pwm-axi-pwmgen-enable-force_align-v1-2-5d6ad8cbf5b4@baylibre.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
Rename the 0x10 register from REG_CONFIG to REG_RSTN. Also rename the
associated bit macros accordingly.
While touching this, move the bit macros close to the register address
macro for better organization.
According to [1], the name of the 0x10 register is REG_RSTN, and there
is a different register named REG_CONFIG (0x18). So we should not be
using REG_CONFIG for the 0x10 register to avoid confusion.
[1]: http://analogdevicesinc.github.io/hdl/library/axi_pwm_gen/index.html
Signed-off-by: David Lechner <dlechner@baylibre.com>
Reviewed-by: Nuno Sa <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20241009-pwm-axi-pwmgen-enable-force_align-v1-1-5d6ad8cbf5b4@baylibre.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
Support a new abstraction for pwm configuration that allows to specify
the time between start of period and the raising edge of the signal
("duty offset").
This is used in a patch series by Trevor Gamblin for triggering an ADC
conversion and afterwards read out the result. See
https://lore.kernel.org/linux-iio/20240909-ad7625_r1-v5-0-60a397768b25@baylibre.com/
for more details.
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Merge tag 'pwm/duty_offset-for-6.13-rc1' of https://git.kernel.org/pub/scm/linux/kernel/git/ukleinek/linux
pwm: Support for duty_offset
Support a new abstraction for pwm configuration that allows to specify
the time between start of period and the raising edge of the signal
("duty offset").
This is used in a patch series by Trevor Gamblin for triggering an ADC
conversion and afterwards read out the result. See
https://lore.kernel.org/linux-iio/20240909-ad7625_r1-v5-0-60a397768b25@baylibre.com/
for more details.
Compared to direct calls to pwmchip_get_drvdata() a dedicated function
has two upsides: A better name and the right type. So the code becomes
easier to read and the new function is harder to use wrongly.
Another side effect (which is the secret motivation for this patch, but
shhh) is that the driver becomes a bit easier to backport to kernel
versions that don't have devm_pwmchip_alloc() yet.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Reviewed-by: Trevor Gamblin <tgamblin@baylibre.com>
Link: https://lore.kernel.org/r/20240923125418.16558-2-u.kleine-koenig@baylibre.com
[ukleinek: added an * to the new function's prototype to make the compiler happy]
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
Use the min() macro to simplify the atmel_tcb_pwm_apply() function
and improve its readability.
Signed-off-by: Shen Lichuan <shenlichuan@vivo.com>
Link: https://lore.kernel.org/r/20240827075749.67583-1-shenlichuan@vivo.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
The modulo register defines the period of the edge-aligned PWM mode
(which is the only mode implemented). The reference manual states:
"The EPWM period is determined by (MOD + 0001h) ..." So the value that
is written to the MOD register must therefore be one less than the
calculated period length. Return -EINVAL if the calculated length is
already zero.
A correct MODULO value is particularly relevant if the PWM has to output
a high frequency due to a low period value.
Fixes: 738a1cfec2 ("pwm: Add i.MX TPM PWM driver support")
Cc: stable@vger.kernel.org
Signed-off-by: Erik Schumacher <erik.schumacher@iris-sensing.com>
Link: https://lore.kernel.org/r/1a3890966d68b9f800d457cbf095746627495e18.camel@iris-sensing.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
This moves pwm_get() and friends above the functions handling
registration of pwmchips. The motivation is that character device
support needs pwm_get() and pwm_put() and so ideally is defined below
these and when a pwmchip is registered this registers the character
device. So the natural order is
pwm_get() and friend
pwm character device symbols
pwm_chip functions
. The advantage of having these in their natural order is that static
functions don't need to be forward declared.
Note that the diff that git produces for this change some functions are
moved down instead. This is technically equivalent, but not how this
change was created.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Link: https://lore.kernel.org/r/193b3d933294da34e020650bff93b778de46b1c5.1726819463.git.u.kleine-koenig@baylibre.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
Provide API functions for consumers to work with waveforms.
Note that one relevant difference between pwm_get_state() and
pwm_get_waveform*() is that the latter yields the actually configured
hardware state, while the former yields the last state passed to
pwm_apply*() and so doesn't account for hardware specific rounding.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Tested-by: Trevor Gamblin <tgamblin@baylibre.com>
Link: https://lore.kernel.org/r/6c97d27682853f603e18e9196043886dd671845d.1726819463.git.u.kleine-koenig@baylibre.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
Up to now the configuration of a PWM setting is described exclusively by
a struct pwm_state which contains information about period, duty_cycle,
polarity and if the PWM is enabled. (There is another member usage_power
which doesn't completely fit into pwm_state, I ignore it here for
simplicity.)
Instead of a polarity the new abstraction has a member duty_offset_ns
that defines when the rising edge happens after the period start. This
is more general, as with a pwm_state the rising edge can only happen at
the period's start or such that the falling edge is at the end of the
period (i.e. duty_offset_ns == 0 or duty_offset_ns == period_length_ns -
duty_length_ns).
A disabled PWM is modeled by .period_length_ns = 0. In my eyes this is a
nice usage of that otherwise unusable setting, as it doesn't define
anything about the future which matches the fact that consumers should
consider the state of the output as undefined and it's just there to say
"No further requirements about the output, you can save some power.".
Further I renamed period and duty_cycle to period_length_ns and
duty_length_ns. In the past there was confusion from time to time about
duty_cycle being measured in nanoseconds because people expected a
percentage of period instead. With "length_ns" as suffix the semantic
should be more obvious to people unfamiliar with the pwm subsystem.
period is renamed to period_length_ns for consistency.
The API for consumers doesn't change yet, but lowlevel drivers can
implement callbacks that work with pwm_waveforms instead of pwm_states.
A new thing about these callbacks is that the calculation of hardware
settings needed to implement a certain waveform is separated from
actually writing these settings. The motivation for that is that this
allows a consumer to query the hardware capabilities without actually
modifying the hardware state.
The rounding rules that are expected to be implemented in the
round_waveform_tohw() are: First pick the biggest possible period not
bigger than wf->period_length_ns. For that period pick the biggest
possible duty setting not bigger than wf->duty_length_ns. Third pick the
biggest possible offset not bigger than wf->duty_offset_ns. If the
requested period is too small for the hardware, it's expected that a
setting with the minimal period and duty_length_ns = duty_offset_ns = 0
is returned and this fact is signaled by a return value of 1.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Tested-by: Trevor Gamblin <tgamblin@baylibre.com>
Link: https://lore.kernel.org/r/df0faa33bf9e7c9e2e5eab8d31bbf61e861bd401.1726819463.git.u.kleine-koenig@baylibre.com
[ukleinek: Update pwm_check_rounding() to return bool instead of int.]
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
