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Linux kernel
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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: 3479bbd1e1f8 ("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: ed6c1476bf7f ("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: caf065f8fd58 ("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>
Add compatible string "fsl,imx93-pwm", "fsl,imx94-pwm" and "fsl,imx95-pwm",
which is backward compatible with i.MX7ULP. Set it to fall back to
"fsl,imx7ulp-pwm".
Signed-off-by: Frank Li <Frank.Li@nxp.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20250306170845.240555-1-Frank.Li@nxp.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
Document pwm compatible for rk3528 which is fallback compatible
of rk3328-pwm group.
Signed-off-by: Chukun Pan <amadeus@jmu.edu.cn>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Acked-by: Uwe Kleine-König <ukleinek@kernel.org>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Link: https://lore.kernel.org/r/20250307120004.959980-2-amadeus@jmu.edu.cn
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
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>
Preparing CONFIG_PWM becoming tristate the right magic to check for the
availability of the pwm functions is using IS_REACHABLE() and not
IS_ENABLED(). The latter gives the wrong result for built-in code with
CONFIG_PWM=m.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Link: https://lore.kernel.org/r/20250217102504.687916-2-u.kleine-koenig@baylibre.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
The PWM core on Rockchip's RK3562 is the same as the one already
included in RK3328. Extend the binding accordingly to allow
compatible = "rockchip,rk3562-pwm", "rockchip,rk3328-pwm";
Signed-off-by: Kever Yang <kever.yang@rock-chips.com>
Acked-by: Uwe Kleine-König <ukleinek@kernel.org>
Acked-by: Rob Herring (Arm) <robh@kernel.org>
Link: https://lore.kernel.org/r/20250227111913.2344207-11-kever.yang@rock-chips.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>
Drop rather useless use of ACPI_PTR() and of_match_ptr().
It also removes the necessity to be dependent acpi.h inclusion.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20250214154031.3395014-1-andriy.shevchenko@linux.intel.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 bd6f2fd5a1d5 ("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 c11e6f0f04db ("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>
Platforms can have a standardized connector/expansion slot that exposes
PWMs signals to expansion boards.
A nexus node [1] allows to remap a phandle list in a consumer node
through a connector node in a generic way. With this remapping, the
consumer node needs to know 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.
[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>
[ukleinek: Make description node use folded style (>) as suggested by Rob]
Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Link: https://lore.kernel.org/r/20250205095547.536083-2-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>
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