[PATCH v2 0/2] Update designware pwm driver

dongxuyang
2026-03-06T09:30:47Z

From: Xuyang Dong <dongxuyang@eswincomputing.com>

There is already a patch [1] for the DesignWare PWM driver,
which is posted by Ben and still under review.
Based on this patch, this series is a continuation of [1]
to add support for IP versions 2.11a and later, which
includes support for "Pulse Width Modulation with 0%
and 100% Duty Cycle".

Supported chips:
ESWIN EIC7700 series SoC.

Test:
Tested this patch on the Sifive HiFive Premier P550 (which uses the EIC7700
SoC).

[1] https://lore.kernel.org/lkml/20230907161242.67190-1-ben.dooks@codethink.co.uk/

Updates:
Change in v2:
- YAML:
- Remove eswin,eic7700-pwm.yaml. Use snps,dw-apb-timers-pwm2.yaml.
The description in snps,dw-apb-timers-pwm2.yaml is better.
- Add the resets property as optional, as defined in the databook.
- Remove snps,pwm-full-range-enable as no additional property is needed.
- Driver:
- Change the file from pwm-dwc-eic7700.c to pwm-dwc-of.c from [1].
- Define DWC_TIM_VERSION_ID_2_11A 2.11a as the baseline version.
- Enable the 0% and 100% duty cycle mode by setting dwc->feature if
the version read from the TIMERS_COMP_VERSION register is later
than or equal to DWC_TIM_VERSION_ID_2_11A.
- Use the DIV_ROUND_UP_ULL() to calculate width in the .apply and
.get_state.
- Additionally, Power Management (PM) support has been added to the
pwm-dwc-of.c driver.
- Drop the headers that are not used.
- Use devm_clk_get_enabled() instead of devm_clk_get().
- Drop of_match_ptr.
- Fix build error with 1ULL << 32.
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202512061720.j31AsgM7-lkp@intel.com/

- Link to v1: https://lore.kernel.org/all/20251205090411.1388-1-dongxuyang@eswincomputing.com/
- Link to v9: https://lore.kernel.org/lkml/20230907161242.67190-1-ben.dooks@codethink.co.uk/

Xuyang Dong (2):
dt-bindings: pwm: dwc: add reset optional
pwm: dwc: add of/platform support

.../bindings/pwm/snps,dw-apb-timers-pwm2.yaml | 3 +
drivers/pwm/Kconfig | 10 +
drivers/pwm/Makefile | 1 +
drivers/pwm/pwm-dwc-core.c | 101 ++++++--
drivers/pwm/pwm-dwc-of.c | 216 ++++++++++++++++++
drivers/pwm/pwm-dwc.h | 25 +-
6 files changed, 327 insertions(+), 29 deletions(-)
create mode 100644 drivers/pwm/pwm-dwc-of.c

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2.34.1