summaryrefslogtreecommitdiffstats
path: root/drivers/pwm/pwm-fsl-ftm.c (follow)
Commit message (Collapse)AuthorAgeFilesLines
* pwm: fsl-ftm: Simplify using devm_pwmchip_add()Uwe Kleine-König2021-09-021-9/+1
| | | | | | | This allows to drop the platform_driver's remove function. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
* pwm: Simplify all drivers with explicit of_pwm_n_cells = 3Uwe Kleine-König2021-05-251-2/+0
| | | | | | | | | | | | | | With the previous commit there is no need for the lowlevel driver any more to specify it it uses two or three cells. So simplify accordingly. The only non-trival change affects the pwm-rockchip driver: It used to only support three cells if the hardware supports polarity. Now the default number depends on the device tree which has to match hardware anyhow (and if it doesn't the error is just a bit delayed as a PWM handle with an inverted setting is catched when pwm_apply_state() is called). Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
* pwm: Always allocate PWM chip base ID dynamicallyUwe Kleine-König2021-03-221-1/+0
| | | | | | | | | | Since commit 5e5da1e9fbee ("pwm: ab8500: Explicitly allocate pwm chip base dynamically") all drivers use dynamic ID allocation explicitly. New drivers are supposed to do the same, so remove support for driver specified base IDs and drop all assignments in the low-level drivers. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
* pwm: fsl-ftm: Convert to devm_platform_ioremap_resource()Yangtao Li2020-12-171-3/+1
| | | | | | | | Use devm_platform_ioremap_resource() to simplify code. Signed-off-by: Yangtao Li <tiny.windzz@gmail.com> Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
* pwm: Ensure pwm_apply_state() doesn't modify the state argumentUwe Kleine-König2019-09-211-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It is surprising for a PWM consumer when the variable holding the requested state is modified by pwm_apply_state(). Consider for example a driver doing: #define PERIOD 5000000 #define DUTY_LITTLE 10 ... struct pwm_state state = { .period = PERIOD, .duty_cycle = DUTY_LITTLE, .polarity = PWM_POLARITY_NORMAL, .enabled = true, }; pwm_apply_state(mypwm, &state); ... state.duty_cycle = PERIOD / 2; pwm_apply_state(mypwm, &state); For sure the second call to pwm_apply_state() should still have state.period = PERIOD and not something the hardware driver chose for a reason that doesn't necessarily apply to the second call. So declare the state argument as a pointer to a const type and adapt all drivers' .apply callbacks. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
* pwm: fsl-ftm: Don't update the state for the caller of pwm_apply_state()Uwe Kleine-König2019-09-211-4/+0
| | | | | | | | | | The pwm-fsl-ftm driver is one of only three PWM drivers which updates the state for the caller of pwm_apply_state(). This might have surprising results if the caller reuses the values expecting them to still represent the same state. Signed-off-by: Uwe Kleine-König <uwe@kleine-koenig.org> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
* Merge tag 'pwm/for-5.3-rc1' of ↵Linus Torvalds2019-07-091-178/+205
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm Pull pwm updates from Thierry Reding: "This set of changes contains a new driver for SiFive SoCs as well as enhancements to the core (device links are used to track dependencies between PWM providers and consumers, support for PWM controllers via ACPI, sysfs will now suspend/resume PWMs that it has claimed) and various existing drivers" * tag 'pwm/for-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm: (37 commits) pwm: fsl-ftm: Make sure to unlock mutex on failure pwm: fsl-ftm: Use write protection for prescaler & polarity pwm: fsl-ftm: More relaxed permissions for updating period pwm: atmel-hlcdc: Add compatible for SAM9X60 HLCDC's PWM pwm: bcm2835: Improve precision of PWM leds: pwm: Support ACPI via firmware-node framework pwm: Add support referencing PWMs from ACPI pwm: rcar: Remove suspend/resume support pwm: sysfs: Add suspend/resume support pwm: Add power management descriptions pwm: meson: Add documentation to the driver pwm: meson: Add support PWM_POLARITY_INVERSED when disabling pwm: meson: Don't cache struct pwm_state internally pwm: meson: Read the full hardware state in meson_pwm_get_state() pwm: meson: Simplify the calculation of the pre-divider and count pwm: meson: Move pwm_set_chip_data() to meson_pwm_request() pwm: meson: Add the per-channel register offsets and bits in a struct pwm: meson: Add the meson_pwm_channel data to struct meson_pwm pwm: meson: Pass struct pwm_device to meson_pwm_calc() pwm: meson: Don't duplicate the polarity internally ...
| * pwm: fsl-ftm: Make sure to unlock mutex on failureThierry Reding2019-06-261-2/+2
| | | | | | | | | | | | | | | | | | | | | | Upon failure to enable clocks while trying to enable the PWM, make sure to unlock the mutex that was taken to avoid a deadlock during subsequent operations. Reported-by: kbuild test robot <lkp@intel.com> Reported-by: Julia Lawall <julia.lawall@lip6.fr> Cc: Patrick Havelange <patrick.havelange@essensium.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
| * pwm: fsl-ftm: Use write protection for prescaler & polarityPatrick Havelange2019-06-261-0/+21
| | | | | | | | | | | | | | | | | | | | | | Modifying the prescaler or polarity value must be done with the write protection disabled. Currently this is working by chance as the write protection is in a disabled state by default. This patch makes sure that we enable/disable the write protection when needed. Signed-off-by: Patrick Havelange <patrick.havelange@essensium.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
| * pwm: fsl-ftm: More relaxed permissions for updating periodPatrick Havelange2019-06-261-180/+186
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The Flextimer has only one period for several channels. The PWM subsystem doesn't allow to model something like that. The current implementation simply disallows changing the period once it has been set, having as a side effect that you need to enable and disable the PWM if you want to change the period. The driver should allow as much freedom as possible for configuring the period and duty cycle. Therefore, this patch reworks the code to allow the following: - period and duty_cycle can be set at will when the PWM is disabled; - when enabling a PWM, verify that the period is either not set yet, or the same as the other already enabled PWM(s), and fail if not; - allow to change the period on the fly when the PWM is the only one enabled. It also allows to have different periods configured for different PWMs. Only one period can be used at a time, thus the first PWM to be enabled will set that period, only other PWMs with that same period can be enabled at the same time. To use another PWM with another period, the enabled PWMs must be disabled first. Example scenario : echo 5000000 > pwm0/period #OK echo 1000000 > pwm0/duty_cycle #OK echo 1000000 > pwm1/period #OK echo 1000000 > pwm1/duty_cycle #OK echo 1 > pwm0/enable #OK echo 1 > pwm1/enable #FAIL (pwm0/period != pwm1/period) echo 0 > pwm0/enable #OK echo 1 > pwm1/enable #OK echo 1000000 > pwm0/period #OK echo 2000000 > pwm0/period #OK echo 1 > pwm0/enable #FAIL (pwm0/period != pwm1/period) echo 2000000 > pwm1/period #OK (pwm1 still running, changed on the fly) echo 1 > pwm0/enable #OK (now pwm0/period == pwm1/period) echo 3000000 > pwm1/period #FAIL (other PWMs running) echo 0 > pwm0/enable #OK echo 3000000 > pwm1/period #OK (only this PWM running) Adapting the code to satisfy these constraints turned up a number of additional issues with the current implementation: - the prescaler value 0 was not used (when it could have been); - when setting the period was not possible, the internal state was inconsistent; - the maximal value for configuring the period was never used; Since all of these interact with each other, rather than trying to fix each individual issue, this patch reworks how the period and duty cycle are set entirely, with the following additional improvements: - implement the new apply() method instead of the individual methods; - return the exact used period/duty_cycle values; - more coherent argument types for period, duty_cycle; Signed-off-by: Patrick Havelange <patrick.havelange@essensium.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
* | treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152Thomas Gleixner2019-05-301-5/+1
|/ | | | | | | | | | | | | | | | | | | | | Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* drivers/pwm: pwm-fsl-ftm: use common header for FlexTimer #definesPatrick Havelange2019-04-251-43/+1
| | | | | | | | | | This also fixes the wrong value for the previously defined FTM_MODE_INIT macro (it was not used). Reviewed-by: Esben Haabendal <esben@haabendal.dk> Signed-off-by: Patrick Havelange <patrick.havelange@essensium.com> Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* pwm: fsl-ftm: Enable support for the new SoC i.MX8QMshenwei.wang@nxp.com2018-07-091-0/+5
| | | | | | | | | Enabled the support for the new SoC i.MX8QM by adding the compatible string of "fsl,imx8qm-ftm-pwm" and its per-compatible data with setting "has_enable_bits" to "true". Signed-off-by: Shenwei Wang <shenwei.wang@nxp.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
* pwm: fsl-ftm: Added the support of per-compatible datashenwei.wang@nxp.com2018-07-091-2/+30
| | | | | | | | | | | On the i.MX8x SoC family, an additional PWM enable bit is added for each PWM channel in the register FTM_SC[23:16]. It supports 8 channels. Bit 16 is for channel 0, and bit 23 is for channel 7. As the IP version information can not be obtained via any of the FTM registers, a property of "has_enable_bits" is added via per-compatible data structure. Signed-off-by: Shenwei Wang <shenwei.wang@nxp.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
* pwm: fsl-ftm: Added a dedicated IP interface clockshenwei.wang@nxp.com2018-07-091-6/+16
| | | | | | | | | | | | | | The current driver assumes that the ftm_sys clock works as one of the clock sources for the IP block as well as the IP interface clock. This assumption does not apply any more on the latest i.MX8x SoC family. On i.MX8x SoCs, a dedicated IP interface clock is introduced and it must be enabled before accessing any FTM registers. Moreover, the clock can not be used as the source clock for the FTM IP block. This patch introduces the ipg_clk as the dedicated IP interface clock and by default it is the same as the ftm_sys clock if not specified. Signed-off-by: Shenwei Wang <shenwei.wang@nxp.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
* pwm: Remove .can_sleep from struct pwm_chipThierry Reding2017-01-041-1/+0
| | | | | | | All PWM devices have been marked as "might sleep" since v4.5, there is no longer a need to differentiate on a per-chip basis. Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
* pwm: fsl-ftm: Use flat regmap cacheStefan Agner2016-04-141-1/+1
| | | | | | | | | | | | | | | | | | | | | Use flat regmap cache to avoid lockdep warning at probe: [ 0.697285] WARNING: CPU: 0 PID: 1 at kernel/locking/lockdep.c:2755 lockdep_trace_alloc+0x15c/0x160() [ 0.697449] DEBUG_LOCKS_WARN_ON(irqs_disabled_flags(flags)) The RB-tree regmap cache needs to allocate new space on first writes. However, allocations in an atomic context (e.g. when a spinlock is held) are not allowed. The function regmap_write calls map->lock, which acquires a spinlock in the fast_io case. Since the pwm-fsl-ftm driver uses MMIO, the regmap bus of type regmap_mmio is being used which has fast_io set to true. The MMIO space of the pwm-fsl-ftm driver is reasonable condense, hence using the much faster flat regmap cache is anyway the better choice. Signed-off-by: Stefan Agner <stefan@agner.ch> Cc: Mark Brown <broonie@kernel.org> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
* pwm: fsl-ftm: Fix clock enable/disable when using PMStefan Agner2015-12-161-33/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A FTM PWM instance enables/disables three clocks: The bus clock, the counter clock and the PWM clock. The bus clock gets enabled on pwm_request, whereas the counter and PWM clocks will be enabled upon pwm_enable. The driver has three closesly related issues when enabling/disabling clocks during suspend/resume: - The three clocks are not treated differently in regards to the individual PWM state enabled/requested. This can lead to clocks getting disabled which have not been enabled in the first place (a PWM channel which only has been requested going through suspend/resume). - When entering suspend, the current behavior relies on the FTM_OUTMASK register: If a PWM output is unmasked, the driver assumes the clocks are enabled. However, some PWM instances have only 2 channels connected (e.g. Vybrid's FTM1). In that case, the FTM_OUTMASK reads 0x3 if all channels are disabled, even if the code wrote 0xff to it before. For those PWM instances, the current approach to detect enabled PWM signals does not work. - A third issue applies to the bus clock only, which can get enabled multiple times (once for each PWM channel of a PWM chip). This is fine, however when entering suspend mode, the clock only gets disabled once. This change introduces a different approach by relying on the enable and prepared counters of the clock framework and using the frameworks PWM signal states to address all three issues. Clocks get disabled during suspend and back enabled on resume regarding to the PWM channels individual state (requested/enabled). Since we do not count the clock enables in the driver, this change no longer clears the Status and Control registers Clock Source Selection (FTM_SC[CLKS]). However, since we disable the selected clock anyway, and we explicitly select the clock source on reenabling a PWM channel this approach should not make a difference in practice. Signed-off-by: Stefan Agner <stefan@agner.ch> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
* pwm: ftm: Add Power Management support for FTM PWMXiubo Li2014-12-011-1/+48
| | | | | | | | Add PM support for FTM PWM driver using callback function suspend and resume in .driver.pm of platform_driver. Signed-off-by: Xiubo Li <Li.Xiubo@freescale.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
* pwm: ftm: Add regmap rbtree type cache supportXiubo Li2014-12-011-0/+11
| | | | | | | | This patch is to prepare for adding PM support for FTM PWM driver using callback function suspend and resume in .driver.pm of platform_driver. Signed-off-by: Xiubo Li <Li.Xiubo@freescale.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
* pwm: ftm: Correctly track usage countXiubo Li2014-12-011-3/+1
| | | | | | | | No matter how many times the FTM PWM is enabled, the use_count will always be one. Signed-off-by: Xiubo Li <Li.Xiubo@freescale.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
* pwm: fsl-ftm: Convert to direct regmap API usageXiubo Li2014-08-201-39/+44
| | | | | | | | | | | | The regmap core supports different endian modes for devices. This patch convert to direct regmap API usage, preparing to support big endianness for LS1 SoC. Using the regmap framework it will be easy to support devices that only differ in endianness with the same device driver. Signed-off-by: Xiubo Li <Li.Xiubo@freescale.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
* pwm: fsl-ftm: Clean up the codeXiubo Li2014-08-201-7/+6
| | | | | | | This patch intends to prepare for converting to direct regmap API usage. Signed-off-by: Xiubo Li <Li.Xiubo@freescale.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
* pwm: fsl-ftm: set pwm_chip can_sleep flagAxel Lin2014-05-231-0/+1
| | | | | | | | | The implementation of .config(), .enable() and .disable() operations in this driver may sleep, thus set pwm_chip can_sleep flag. Signed-off-by: Axel Lin <axel.lin@ingics.com> Acked-by: Xiubo Li <Li.Xiubo@freescale.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
* pwm: Add Freescale FTM PWM driver supportXiubo Li2014-03-181-0/+495
The FTM PWM device can be found on Vybrid VF610 Tower and Layerscape LS-1 SoCs. Signed-off-by: Xiubo Li <Li.Xiubo@freescale.com> Signed-off-by: Alison Wang <b18965@freescale.com> Signed-off-by: Jingchang Lu <b35083@freescale.com> Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de> Reviewed-by: Yuan Yao <yao.yuan@freescale.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>