[PATCH v8 00/17] acpi/pwm/i915: Convert pwm-crc and i915 driver's PWM code to use the atomic PWM API

Hans de Goede
2020-08-30T12:58:19Z

Hi All,

Unfortunately while testing some unrelated things I found another issue with
this series related to the CHT ACPI GFX0._PS3 code poking the PWM controller
in unexpected ways.

This new version contains a new patch: "[PATCH v8 07/17] pwm: lpss: Always
update state and set update bit" fixing this. It also contains the same
change in: "PATCH v8 06/17] pwm: lpss: Use pwm_lpss_restore() when restoring
state on resume". Rather then adding the below check and then dropping it in
the new patch, I've squashed the dropping of these lines:

/* If we did not reach S0i3/S3 the controller keeps its state */
if (ctrl == lpwm->saved_ctrl[i])
continue;

Directly into the original commit leading to a cleaner history.

As discussed before, because of interdependencies of the patches
I plan to push the entire series to drm-intel-next-queued once the
series has passed CI.

I still plan to do this as soon as I get a Reviewed-by or Acked-by for
the new pwm-lpss.c patch.

Thierry, I believe from our previous discussion that you are ok with
pushing the pwm-crc and pwm-lpss patches through the drm-intel tree,
but you have not given your Acked-by for this. If you are not ok with
me pushing these out this way please let me now ASAP. If you are ok
with this an Acked-by would be appreciated.

This series has been tested (and re-tested after adding various bug-fixes)
extensively. It has been tested on the following devices:

-Asus T100TA BYT + CRC-PMIC PWM
-Toshiba WT8-A BYT + CRC-PMIC PWM
-Thundersoft TS178 BYT + CRC-PMIC PWM, inverse PWM
-Asus T100HA CHT + CRC-PMIC PWM
-Terra Pad 1061 BYT + LPSS PWM
-Trekstor Twin 10.1 BYT + LPSS PWM
-Asus T101HA CHT + LPSS PWM
-GPD Pocket CHT + LPSS PWM
-Acer One S1003 CHT + LPSS PWM

Regards,

Hans

Changelog:

Changes in v8:
- Add a new patch dealing with the ACPI/DSDT GFX0._PS3 code poking the PWM controller
in unexpected ways on some Cherry Trail devices

Changes in v7:
- Fix a u64 divide leading to undefined reference to `__udivdi3' errors on 32 bit
platforms by casting the divisor to an unsigned long

Changes in v6:
- Rebase on v5.9-rc1
- Adjust pwm-crc patches for pwm_state.period and .duty_cycle now being u64

Changes in v5:
- Dropped the "pwm: lpss: Correct get_state result for base_unit == 0"
patch. The base_unit == 0 condition should never happen and sofar it is
unclear what the proper behavior / correct values to store in the
pwm_state should be when this does happen. Since this patch was added as
an extra pwm-lpss fix in v4 of this patch-set and otherwise is orthogonal
to the of this patch-set just drop it (again).
- "[PATCH 04/16] pwm: lpss: Add range limit check for the base_unit register value"
- Use clamp_val(... instead of clam_t(unsigned long long, ...
- "[PATCH 05/16] pwm: lpss: Add pwm_lpss_prepare_enable() helper"
- This is a new patch in v5 of this patchset
- [PATCH 06/16] pwm: lpss: Use pwm_lpss_apply() when restoring state on resume
- Use the new pwm_lpss_prepare_enable() helper

Changes in v4:
- "[PATCH v4 06/16] pwm: lpss: Correct get_state result for base_unit == 0"
- This is a new patch in v4 of this patchset
- "[PATCH v4 12/16] pwm: crc: Implement get_state() method"
- Use DIV_ROUND_UP when calculating the period and duty_cycle values
- "[PATCH v4 16/16] drm/i915: panel: Use atomic PWM API for devs with an external PWM controller"
- Add a note to the commit message about the changes in pwm_disable_backlight()
- Use the pwm_set/get_relative_duty_cycle() helpers

Changes in v3:
- "[PATCH v3 04/15] pwm: lpss: Add range limit check for the base_unit register value"
- Use base_unit_range - 1 as maximum value for the clamp()
- "[PATCH v3 05/15] pwm: lpss: Use pwm_lpss_apply() when restoring state on resume"
- This replaces the "pwm: lpss: Set SW_UPDATE bit when enabling the PWM"
patch from previous versions of this patch-set, which really was a hack
working around the resume issue which this patch fixes properly.
- PATCH v3 6 - 11 pwm-crc changes:
- Various small changes resulting from the reviews by Andy and Uwe,
including some refactoring of the patches to reduce the amount of churn
in the patch-set

Changes in v2:
- Fix coverletter subject
- Drop accidentally included debugging patch
- "[PATCH v3 02/15] ACPI / LPSS: Save Cherry Trail PWM ctx registers only once (
- Move #define LPSS_SAVE_CTX_ONCE define to group it with LPSS_SAVE_CTX