linux/drivers/pwm
Hans de Goede 1d375b58c1 pwm: lpss: platform: Save/restore the ctrl register over a suspend/resume
On some devices the contents of the ctrl register get lost over a
suspend/resume and the PWM comes back up disabled after the resume.

This is seen on some Bay Trail devices with the PWM in ACPI enumerated
mode, so it shows up as a platform device instead of a PCI device.

If we still think it is enabled and then try to change the duty-cycle
after this, we end up with a "PWM_SW_UPDATE was not cleared" error and
the PWM is stuck in that state from then on.

This commit adds suspend and resume pm callbacks to the pwm-lpss-platform
code, which save/restore the ctrl register over a suspend/resume, fixing
this.

Note that:

1) There is no need to do this over a runtime suspend, since we
only runtime suspend when disabled and then we properly set the enable
bit and reprogram the timings when we re-enable the PWM.

2) This may be happening on more systems then we realize, but has been
covered up sofar by a bug in the acpi-lpss.c code which was save/restoring
the regular device registers instead of the lpss private registers due to
lpss_device_desc.prv_offset not being set. This is fixed by a later patch
in this series.

Cc: stable@vger.kernel.org
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2018-06-06 10:00:39 +02:00
..
core.c pwm: Silently error out on EPROBE_DEFER 2017-07-06 08:29:16 +02:00
Kconfig pwm: Changes for v4.17-rc1 2018-04-13 15:46:21 -07:00
Makefile pwm: remove pwm-bfin driver 2018-03-26 15:57:08 +02:00
pwm-ab8500.c pwm: drop owner assignment from platform_drivers 2014-10-20 16:21:28 +02:00
pwm-atmel-hlcdc.c pwm: atmel-hlcdc: Implement the suspend/resume hooks 2017-04-06 17:45:02 +02:00
pwm-atmel-tcb.c pwm: simplify getting .drvdata 2018-04-30 10:40:57 +02:00
pwm-atmel.c pwm: atmel: Enable PWM on sama5d2 2017-04-06 17:45:03 +02:00
pwm-bcm2835.c pwm: bcm2835: Support for polarity setting via DT 2017-08-21 07:27:58 +02:00
pwm-bcm-iproc.c pwm: Add support for Broadcom iProc PWM controller 2016-07-11 12:49:25 +02:00
pwm-bcm-kona.c pwm: Remove .can_sleep from struct pwm_chip 2017-01-04 09:40:54 +01:00
pwm-berlin.c pwm: Remove .can_sleep from struct pwm_chip 2017-01-04 09:40:54 +01:00
pwm-brcmstb.c pwm: Remove .can_sleep from struct pwm_chip 2017-01-04 09:40:54 +01:00
pwm-clps711x.c pwm: clps711x: Changing the compatibility string to match with the smallest supported chip 2016-07-06 17:38:17 +02:00
pwm-crc.c pwm: Use pwm_get/set_xxx() helpers where appropriate 2016-05-17 14:44:59 +02:00
pwm-cros-ec.c pwm: cros-ec: Fix transposed param settings 2017-07-06 17:16:37 +02:00
pwm-ep93xx.c pwm: Add the pwm_is_enabled() helper 2015-07-20 09:46:06 +02:00
pwm-fsl-ftm.c pwm: Remove .can_sleep from struct pwm_chip 2017-01-04 09:40:54 +01:00
pwm-hibvt.c pwm: hibvt: Explicitly request exclusive reset control 2017-08-21 08:52:40 +02:00
pwm-img.c pwm: img: Add runtime PM 2017-11-15 10:38:37 +01:00
pwm-imx.c pwm: imx: Let PWM be active during suspend 2018-03-28 00:17:36 +02:00
pwm-jz4740.c pwm: jz4740: Add support for devicetree 2018-03-28 00:23:56 +02:00
pwm-lp3943.c pwm: Remove .can_sleep from struct pwm_chip 2017-01-04 09:40:54 +01:00
pwm-lpc18xx-sct.c pwm: lpc-18xx: use pwm_set_chip_data 2016-09-08 10:55:05 +02:00
pwm-lpc32xx.c pwm: lpc32xx: Set PWM_PIN_LEVEL bit to default value 2016-07-11 12:49:29 +02:00
pwm-lpss-pci.c pwm: lpss: Set enable-bit before waiting for update-bit to go low 2017-04-06 14:48:14 +02:00
pwm-lpss-platform.c pwm: lpss: platform: Save/restore the ctrl register over a suspend/resume 2018-06-06 10:00:39 +02:00
pwm-lpss.c pwm: lpss: platform: Save/restore the ctrl register over a suspend/resume 2018-06-06 10:00:39 +02:00
pwm-lpss.h pwm: lpss: platform: Save/restore the ctrl register over a suspend/resume 2018-06-06 10:00:39 +02:00
pwm-mediatek.c pwm: mediatek: Improve precision in rate calculation 2018-03-28 00:32:25 +02:00
pwm-meson.c pwm: meson: Fix allocation of PWM channel array 2018-04-30 10:32:30 +02:00
pwm-mtk-disp.c pwm: Add MediaTek MT2701 display PWM driver support 2016-09-06 10:48:53 +02:00
pwm-mxs.c pwm: Remove .can_sleep from struct pwm_chip 2017-01-04 09:40:54 +01:00
pwm-omap-dmtimer.c pwm: pwm-omap-dmtimer: Adapt driver to utilize dmtimer pdata ops 2018-02-22 10:54:24 -08:00
pwm-pca9685.c pwm: pca9685: clarify pca9685_set_sleep_mode() interface. 2017-07-25 13:41:59 +02:00
pwm-puv3.c pwm: puv3: Delete an error message for a failed memory allocation 2018-03-27 23:27:05 +02:00
pwm-pxa.c pwm: constify pwm_ops structures 2017-01-19 00:38:17 +01:00
pwm-rcar.c pwm: simplify getting .drvdata 2018-04-30 10:40:57 +02:00
pwm-renesas-tpu.c pwm: renesas-tpu: Remove support for SH7372 2017-08-18 17:27:14 +02:00
pwm-rockchip.c pwm: rockchip: Add rk3328 support 2017-08-18 17:44:34 +02:00
pwm-samsung.c pwm: pwm-samsung: fix suspend/resume support 2017-08-21 10:39:12 +02:00
pwm-spear.c pwm: drop owner assignment from platform_drivers 2014-10-20 16:21:28 +02:00
pwm-sti.c pwm: Remove .can_sleep from struct pwm_chip 2017-01-04 09:40:54 +01:00
pwm-stm32-lp.c pwm: stm32: LPTimer: Use 3 cells ->of_xlate() 2018-03-28 00:54:56 +02:00
pwm-stm32.c pwm: stm32: Protect common prescaler for all channels 2018-03-28 00:37:37 +02:00
pwm-stmpe.c pwm: stmpe: Fix wrong register offset for hwpwm=2 case 2017-12-05 09:33:05 +01:00
pwm-sun4i.c pwm: sun4i: Simplify controller mapping 2018-03-28 01:12:12 +02:00
pwm-tegra.c pwm: tegra: Explicitly request exclusive reset control 2017-08-21 08:53:07 +02:00
pwm-tiecap.c pwm: tiecap: Set driver data before runtime PM enable 2017-08-21 08:31:37 +02:00
pwm-tiehrpwm.c pwm: tiehrpwm: Set driver data before runtime PM enable 2017-08-21 08:42:56 +02:00
pwm-tipwmss.c pwm: pwm-tipwmss: Remove all runtime PM gets/puts 2016-09-06 10:48:54 +02:00
pwm-twl-led.c mfd: twl: Move header file out of I2C realm 2017-09-04 14:41:02 +01:00
pwm-twl.c mfd: twl: Move header file out of I2C realm 2017-09-04 14:41:02 +01:00
pwm-vt8500.c pwm: vt8500: Undo preparation of a clock source. 2017-07-25 13:43:28 +02:00
pwm-zx.c pwm: Add ZTE ZX PWM device driver 2017-08-21 08:11:24 +02:00
sysfs.c pwm: sysfs: Use put_device() instead of kfree() 2018-03-28 01:18:53 +02:00