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* Merge tag 'pwm/for-6.15-rc2-fixes' of ↵Linus Torvalds2025-04-126-31/+42
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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()
| * pwm: axi-pwmgen: Let .round_waveform_tohw() signal when request was rounded upUwe Kleine-König2025-04-071-3/+7
| | | | | | | | | | | | | | | | | | | | | | | | 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>
| * pwm: stm32: Search an appropriate duty_cycle if period cannot be modifiedUwe Kleine-König2025-04-071-9/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: deaba9cff809 ("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>
| * pwm: Let pwm_set_waveform() succeed even if lowlevel driver rounded upUwe Kleine-König2025-04-071-6/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * pwm: fsl-ftm: Handle clk_get_rate() returning 0Uwe Kleine-König2025-04-041-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | 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>
| * pwm: rcar: Improve register calculationUwe Kleine-König2025-04-041-11/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * pwm: mediatek: Prevent divide-by-zero in pwm_mediatek_config()Josh Poimboeuf2025-04-021-2/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | Merge tag 'pinctrl-v6.15-1' of ↵Linus Torvalds2025-03-291-2/+2
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: lpss: Actually use a module namespace by defining the namespace earlierUwe Kleine-König2025-02-031-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | pwm: stmpe: Allow to compile as a moduleUwe Kleine-König2025-03-032-3/+24
| | | | | | | | | | | | | | | | | | 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>
* | pwm: Strengthen dependency for PWM_SIFIVEUwe Kleine-König2025-02-151-1/+1
| | | | | | | | | | | | | | | | | | | | | | 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>
* | pwm: clps711x: Drop of_match_ptr() usage for .of_match_tableUwe Kleine-König2025-02-151-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | pwm: pca9685: Drop ACPI_PTR() and of_match_ptr()Andy Shevchenko2025-02-151-7/+2
| | | | | | | | | | | | | | | | | | 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>
* | pwm: Add support for pwm nexus dt bindingsHerve Codina2025-02-121-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | pwm: Add upgrade path to #pwm-cells = <3> for users of of_pwm_single_xlate()Uwe Kleine-König2025-02-101-0/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | pwm: gpio: Switch to use hrtimer_setup()Nam Cao2025-02-071-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | pwm: sophgo: add driver for Sophgo SG2042 PWMChen Wang2025-02-053-0/+205
| | | | | | | | | | | | | | | | | | | | Add a PWM driver for PWM controller in Sophgo SG2042 SoC. Signed-off-by: Sean Young <sean@mess.org> Signed-off-by: Chen Wang <unicorn_wang@outlook.com> Link: https://lore.kernel.org/r/ae8ea1bf0bb0a09336cd8b7f627a994630524bba.1738737617.git.unicorn_wang@outlook.com [ukleinek: Drop unneeded reset_control_assert() from error path] Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
* | pwm: lpss: Only include <linux/pwm.h> where neededUwe Kleine-König2025-02-042-1/+1
|/ | | | | | | | | | | 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>
* Merge tag 'driver-core-6.14-rc1' of ↵Linus Torvalds2025-01-281-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 ...
| * Merge 6.13-rc7 into driver-core-nextGreg Kroah-Hartman2025-01-131-1/+1
| |\ | | | | | | | | | | | | | | | | | | 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>
| * | driver core: Constify API device_find_child() and adapt for various usagesZijun Hu2025-01-031-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | | Merge tag 'pwm/for-6.14-rc1-fixes' of ↵Linus Torvalds2025-01-272-3/+12
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
| * | | pwm: Ensure callbacks exist before calling themUwe Kleine-König2025-01-231-2/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: 6c5126c6406d ("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>
| * | | pwm: microchip-core: fix incorrect comparison with max periodConor Dooley2025-01-231-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: 2bf7ecf7b4ff ("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>
* | | | Merge tag 'pwm/for-6.14-rc1' of ↵Linus Torvalds2025-01-224-17/+21
|\| | | | |_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
| * | pwm: stm32: Add check for clk_enable()Mingwei Zheng2025-01-171-2/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add check for the return value of clk_enable() to catch the potential error. Fixes: 19f1016ea960 ("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>
| * | pwm: stm32-lp: Add check for clk_enable()Mingwei Zheng2024-12-181-2/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add check for the return value of clk_enable() to catch the potential error. We used APP-Miner to find it. Fixes: e70a540b4e02 ("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>
| * | pwm: Replace deprecated PCI functionsPhilipp Stanner2024-12-182-13/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | pcim_iomap_table() and pcim_request_regions() have been deprecated in commit e354bb84a4c1 ("PCI: Deprecate pcim_iomap_table(), pcim_iomap_regions_request_all()") and commit d140f80f60358 ("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>
* | | Merge tag 'pwm/for-6.13-rc4-fixes' of ↵Linus Torvalds2024-12-191-1/+1
|\| | | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | 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()
| * pwm: stm32: Fix complementary output in round_waveform_tohw()Fabrice Gasnier2024-12-181-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | 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: deaba9cff809 ("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>
* | module: Convert default symbol namespace to string literalMasahiro Yamada2024-12-033-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | Commit cdd30ebb1b9f ("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>
* | module: Convert symbol namespace to string literalPeter Zijlstra2024-12-023-3/+3
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Clean up the existing export namespace code along the same lines of commit 33def8498fdd ("treewide: Convert macro and uses of __section(foo) to __section("foo")") and for the same reason, it is not desired for the namespace argument to be a macro expansion itself. Scripted using git grep -l -e MODULE_IMPORT_NS -e EXPORT_SYMBOL_NS | while read file; do awk -i inplace ' /^#define EXPORT_SYMBOL_NS/ { gsub(/__stringify\(ns\)/, "ns"); print; next; } /^#define MODULE_IMPORT_NS/ { gsub(/__stringify\(ns\)/, "ns"); print; next; } /MODULE_IMPORT_NS/ { $0 = gensub(/MODULE_IMPORT_NS\(([^)]*)\)/, "MODULE_IMPORT_NS(\"\\1\")", "g"); } /EXPORT_SYMBOL_NS/ { if ($0 ~ /(EXPORT_SYMBOL_NS[^(]*)\(([^,]+),/) { if ($0 !~ /(EXPORT_SYMBOL_NS[^(]*)\(([^,]+), ([^)]+)\)/ && $0 !~ /(EXPORT_SYMBOL_NS[^(]*)\(\)/ && $0 !~ /^my/) { getline line; gsub(/[[:space:]]*\\$/, ""); gsub(/[[:space:]]/, "", line); $0 = $0 " " line; } $0 = gensub(/(EXPORT_SYMBOL_NS[^(]*)\(([^,]+), ([^)]+)\)/, "\\1(\\2, \"\\3\")", "g"); } } { print }' $file; done Requested-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://mail.google.com/mail/u/2/#inbox/FMfcgzQXKWgMmjdFwwdsfgxzKpVHWPlc Acked-by: Greg KH <gregkh@linuxfoundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* pwm: Assume a disabled PWM to emit a constant inactive outputUwe Kleine-König2024-11-071-3/+7
| | | | | | | | | | | | | | | | | | | 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: 3ad1f3a33286 ("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>
* pwm: core: export pwm_get_state_hw()David Lechner2024-11-031-13/+27
| | | | | | | | | | | | | | | 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>
* pwm: core: use device_match_name() instead of strcmp(dev_name(...Andy Shevchenko2024-10-251-3/+1
| | | | | | | | | | | | | 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>
* pwm: imx27: Use clk_bulk_*() API to simplify clock handlingFrank Li2024-10-251-41/+22
| | | | | | | | Simplify the clock handling logic by using the clk_bulk_*() API. Signed-off-by: Frank Li <Frank.Li@nxp.com> Link: https://lore.kernel.org/r/20240910-pwm-v3-2-fbb047896618@nxp.com Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
* pwm: imx27: Workaround of the pwm output bug when decrease the duty cycleClark Wang2024-10-251-2/+96
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: 166091b1894d ("[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>
* pwm: axi-pwmgen: Enable FORCE_ALIGN by defaultDavid Lechner2024-10-251-0/+12
| | | | | | | | | | | | | | | | | | | | | | | | 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>
* pwm: axi-pwmgen: Rename 0x10 registerDavid Lechner2024-10-251-6/+6
| | | | | | | | | | | | | | | | | | | 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>
* Merge tag 'pwm/duty_offset-for-6.13-rc1' of ↵Uwe Kleine-König2024-10-253-416/+1201
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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.
| * pwm: stm32: Fix error checking for a regmap_read() callUwe Kleine-König2024-10-041-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Without first assigning ret, it always evaluates to zero because otherwise this code isn't reached. So assign the return code of regmap_read() to ret to make the following error path do something. This issue was spotted by Coverity. Reported-by: Kees Bakker <kees@ijzerbout.nl> Link: https://lore.kernel.org/linux-pwm/b0199625-9dbb-414b-8948-26ad86fd2740@ijzerbout.nl Fixes: deaba9cff809 ("pwm: stm32: Implementation of the waveform callbacks") Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com> Link: https://lore.kernel.org/r/20241003114216.163715-2-u.kleine-koenig@baylibre.com Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
| * pwm: Reorder symbols in core.cUwe Kleine-König2024-09-281-156/+156
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * pwm: stm32: Implementation of the waveform callbacksUwe Kleine-König2024-09-281-221/+391
| | | | | | | | | | | | | | | | | | Convert the stm32 pwm driver to use the new callbacks for hardware programming. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com> Link: https://lore.kernel.org/r/332d4f736d8360038d03f109c013441c655eea23.1726819463.git.u.kleine-koenig@baylibre.com Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
| * pwm: axi-pwmgen: Implementation of the waveform callbacksUwe Kleine-König2024-09-281-43/+105
| | | | | | | | | | | | | | | | | | | | Convert the axi-pwmgen driver to use the new callbacks for hardware programming. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com> Tested-by: Trevor Gamblin <tgamblin@baylibre.com> Link: https://lore.kernel.org/r/922277f07b1d1fb9c9cd915b1ec3fdeec888a916.1726819463.git.u.kleine-koenig@baylibre.com Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
| * pwm: Add tracing for waveform callbacksUwe Kleine-König2024-09-281-4/+20
| | | | | | | | | | | | | | | | | | | | This adds trace events for the recently introduced waveform callbacks. With the introduction of some helper macros consistency among the different events is ensured. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com> Link: https://lore.kernel.org/r/1d71879b0de3bf01459c7a9d0f040d43eb5ace56.1726819463.git.u.kleine-koenig@baylibre.com Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
| * pwm: Provide new consumer API functions for waveformsUwe Kleine-König2024-09-281-0/+261
| | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * pwm: New abstraction for PWM waveformsUwe Kleine-König2024-09-281-21/+213
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * pwm: Add more lockingUwe Kleine-König2024-09-271-8/+92
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This ensures that a pwm_chip that has no corresponding driver isn't used and that a driver doesn't go away while a callback is still running. In the presence of device links this isn't necessary yet (so this is no fix) but for pwm character device support this is needed. To not serialize all pwm_apply_state() calls, this introduces a per chip lock. An additional complication is that for atomic chips a mutex cannot be used (as pwm_apply_atomic() must not sleep) and a spinlock cannot be held while calling an operation for a sleeping chip. So depending on the chip being atomic or not a spinlock or a mutex is used. An additional change implemented here is that on driver remove the .free() callback is called for each requested pwm_device. This is the right time because later (e.g. when the consumer calls pwm_put()) the free function is (maybe) not available any more. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com> Link: https://lore.kernel.org/r/026aa891c8270a11723a1ba7e4256f456f7e1e86.1726819463.git.u.kleine-koenig@baylibre.com Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
* | pwm: axi-pwmgen: Create a dedicated function for getting driver data from a chipUwe Kleine-König2024-10-251-2/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | pwm: atmel-tcb: Use min() macroShen Lichuan2024-10-251-2/+2
| | | | | | | | | | | | | | | | | | 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>
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