Re: [PATCH v3 0/6] PWM support for allwinner sun8i R40/T3/V40 SOCs.

From: Icenowy Zheng
Date: Thu Jul 22 2021 - 00:02:16 EST


Hao,

Would you mind me to continue on this work? Newer Allwinner SoCs have
PWM controllers similar to the R40 one.

Yours sincerely,
Icenowy Zheng


在 2018-11-26星期一的 00:18 +0800,Hao Zhang写道:
> PWM support for allwinner sun8i R40/T3/V40 SOCs.
>
> The sun8i R40/T3/V40 PWM has 8 PWM channals and divides to 4 PWM
> pairs,
> each PWM pair built-in 1 clock module, 2 timer logic module and 1
> programmable dead-time generator, it also support waveform capture.
> It has 2 clock sources OSC24M and APB1, it is different with the
> sun4i-pwm driver, Therefore add a new driver for it.
>
> Some test method:
> cd /sys/class/pwm/pwmchip0
> echo 0 > export
> cd pwm0
> echo 1000 > period
> echo 500 > duty_cycle
> echo 1 > enable
> then check the PB2 pin with oscilloscope.
>
> v3 Changes:
> 1. fix coding format.
> 2. use 2/ilog2 instead of divide table
> 3. remove spinlock.
> 4. remove sun8i_pwm_data structure and use DT to parse pwm-channals 
> 5. remove inline because complier knows it better.
> 6. don't hardcode clock source and parse two clock source from dt
> "mux-0"
>    and "mux-1"
> 7. remove bypass method.
> 8. add a method to change clock source when mux-0 is not support the
>    input period it can change to mux-1.
> 9. add cycle range check.
> 10. add some variable to make it more readability.
> 11. add clk_disable_unprepare when some false accur.
>
> v2 Changes:
> 1. change sun8i-r40 symbol to sun8i.
> 2. change pwm0_pin, pwm0-pin to pwm_ch0_pin, pwm-ch0-pin.
> 3. remove clk_disable_unprepare(), check !match and IS_ERR(pwm-
> >regmap).
>
> Hao Zhang (6):
>   Documentation: ARM: sunxi: pwm: add Allwinner sun8i.
>   ARM: dtsi: add pwm node for sun8i R40.
>   ARM: dts: add PWM for Bananapi M2 Ultrar board.
>   DEV: CLK: add function to check the using clock name of driver.
>   DEV: CLK: sunxi ccu: export clk_apb1 for sun8i-r40 soc pwm.
>   ARM: PWM: add allwinner sun8i R40/T3/V40 PWM support.
>
>  .../devicetree/bindings/pwm/pwm-sun8i.txt          |  24 ++
>  arch/arm/boot/dts/sun8i-r40-bananapi-m2-ultra.dts  |   6 +
>  arch/arm/boot/dts/sun8i-r40.dtsi                   |  17 +
>  drivers/clk/clk.c                                  |   6 +
>  drivers/clk/sunxi-ng/ccu-sun8i-r40.h               |   4 +-
>  drivers/pwm/Kconfig                                |  12 +-
>  drivers/pwm/Makefile                               |   1 +
>  drivers/pwm/pwm-sun8i.c                            | 418
> +++++++++++++++++++++
>  include/dt-bindings/clock/sun8i-r40-ccu.h          |   2 +
>  include/linux/clk-provider.h                       |   1 +
>  10 files changed, 489 insertions(+), 2 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/pwm/pwm-
> sun8i.txt
>  create mode 100644 drivers/pwm/pwm-sun8i.c
>