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linux/drivers/pwm
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Paul Cercueil a020f22a4f pwm: jz4740: Make PWM start with the active part 
The PWM in Ingenic SoCs starts in inactive state until the internal
timer reaches the duty value, then becomes active until the timer
reaches the period value. In theory, we should then use (period - duty)
as the real duty value, as a high duty value would otherwise result in
the PWM pin being inactive most of the time.

This is the reason why the duty value was inverted in the driver until
now, but it still had the problem that it would not start with the
active part.

To address this remaining issue, the common trick is to invert the
duty, and invert the polarity when the PWM is enabled.

Since the duty was already inverted, and we invert it again, we now
program the hardware for the requested duty, and simply invert the
polarity when the PWM is enabled.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
 		2020-06-02 14:24:26 +02:00
..
Kconfig pwm: jz4740: Drop dependency on MACH_INGENIC 2020-06-02 14:23:42 +02:00
Makefile pwm: Add support for Azoteq IQS620A PWM generator 2020-04-14 16:02:28 +02:00
core.c pwm: Add missing '\n' in log messages 2020-04-14 15:57:51 +02:00
pwm-ab8500.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 194 2019-05-30 11:29:22 -07:00
pwm-atmel-hlcdc.c pwm: Ensure pwm_apply_state() doesn't modify the state argument 2019-09-21 03:25:10 +02:00
pwm-atmel-tcb.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 194 2019-05-30 11:29:22 -07:00
pwm-atmel.c pwm: atmel: Implement .get_state() 2020-01-08 13:47:46 +01:00
pwm-bcm-iproc.c pwm: bcm-iproc: Prevent unloading the driver module while in use 2019-11-08 18:38:06 +01:00
pwm-bcm-kona.c pwm: bcm-kona: Update macros to remove braces around numbers 2019-03-04 12:52:49 +01:00
pwm-bcm2835.c pwm: bcm2835: Dynamically allocate base 2020-03-30 16:55:25 +02:00
pwm-berlin.c pwm: Clear chip_data in pwm_put() 2019-05-09 17:09:54 +02:00
pwm-brcmstb.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157 2019-05-30 11:26:37 -07:00
pwm-clps711x.c pwm: clps711x: Switch to SPDX identifier 2018-12-24 12:06:56 +01:00
pwm-crc.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174 2019-05-30 11:26:41 -07:00
pwm-cros-ec.c pwm: cros-ec: Cache duty cycle value 2019-12-09 10:05:42 +01:00
pwm-ep93xx.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157 2019-05-30 11:26:37 -07:00
pwm-fsl-ftm.c pwm: Ensure pwm_apply_state() doesn't modify the state argument 2019-09-21 03:25:10 +02:00
pwm-hibvt.c pwm: Ensure pwm_apply_state() doesn't modify the state argument 2019-09-21 03:25:10 +02:00
pwm-img.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 178 2019-05-30 11:29:19 -07:00
pwm-imx-tpm.c pwm: imx-tpm: Remove unused includes 2020-03-30 16:55:26 +02:00
pwm-imx1.c pwm: imx: Split into two drivers 2019-01-16 08:45:33 +01:00
pwm-imx27.c pwm: imx27: Remove unused include of of_device.h 2020-03-30 16:55:26 +02:00
pwm-iqs620a.c pwm: Add support for Azoteq IQS620A PWM generator 2020-04-14 16:02:28 +02:00
pwm-jz4740.c pwm: jz4740: Make PWM start with the active part 2020-06-02 14:24:26 +02:00
pwm-lp3943.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 372 2019-06-05 17:37:10 +02:00
pwm-lpc18xx-sct.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 178 2019-05-30 11:29:19 -07:00
pwm-lpc32xx.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 372 2019-06-05 17:37:10 +02:00
pwm-lpss-pci.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
pwm-lpss-platform.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
pwm-lpss.c pwm: lpss: Fix get_state runtime-pm reference handling 2020-06-02 14:21:42 +02:00
pwm-lpss.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
pwm-mediatek.c pwm: mediatek: Add MT7629 compatible string 2019-09-26 13:27:50 +02:00
pwm-meson.c pwm: meson: Remove redundant assignment to variable fin_freq 2020-04-03 21:40:56 +02:00
pwm-mtk-disp.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174 2019-05-30 11:26:41 -07:00
pwm-mxs.c pwm: mxs: Remove unused include of of_address.h 2020-03-30 16:55:27 +02:00
pwm-omap-dmtimer.c pwm: omap-dmtimer: Implement .apply callback 2020-03-30 18:03:08 +02:00
pwm-pca9685.c pwm: pca9685: Fix PWM/GPIO inter-operation 2020-04-03 21:41:42 +02:00
pwm-puv3.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
pwm-pxa.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
pwm-rcar.c pwm: rcar: Fix late Runtime PM enablement 2020-03-30 18:03:05 +02:00
pwm-renesas-tpu.c pwm: renesas-tpu: Drop confusing registered message 2020-03-30 18:03:06 +02:00
pwm-rockchip.c pwm: Ensure pwm_apply_state() doesn't modify the state argument 2019-09-21 03:25:10 +02:00
pwm-samsung.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 178 2019-05-30 11:29:19 -07:00
pwm-sifive.c pwm: Ensure pwm_apply_state() doesn't modify the state argument 2019-09-21 03:25:10 +02:00
pwm-spear.c pwm: drop owner assignment from platform_drivers 2014-10-20 16:21:28 +02:00
pwm-sprd.c pwm: Ensure pwm_apply_state() doesn't modify the state argument 2019-09-21 03:25:10 +02:00
pwm-sti.c pwm: Remove dev_err() usage after platform_get_irq() 2019-09-21 00:58:35 +02:00
pwm-stm32-lp.c pwm: stm32-lp: Add check in case requested period cannot be achieved 2019-09-21 03:25:10 +02:00
pwm-stm32.c pwm: stm32: Remove automatic output enable 2020-01-20 13:47:36 +01:00
pwm-stmpe.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
pwm-sun4i.c pwm: sun4i: Support direct clock output on Allwinner A64 2020-06-02 14:20:11 +02:00
pwm-tegra.c pwm: tegra: Add support for Tegra194 2020-03-30 18:03:04 +02:00
pwm-tiecap.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 61 2019-05-24 17:36:45 +02:00
pwm-tiehrpwm.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 61 2019-05-24 17:36:45 +02:00
pwm-twl-led.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
pwm-twl.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
pwm-vt8500.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 282 2019-06-05 17:36:37 +02:00
pwm-zx.c pwm: Ensure pwm_apply_state() doesn't modify the state argument 2019-09-21 03:25:10 +02:00
sysfs.c pwm: Changes for v5.3-rc1 2019-07-09 08:57:45 -07:00