RE: [PATCH 1/2] pinctrl: imx: Support building SCU pinctrl driver as module

[Anson Huang <anson.huang@xxxxxxx>]

Hi, Daniel


> Subject: Re: [PATCH 1/2] pinctrl: imx: Support building SCU pinctrl driver as
> module
> 
> On 7/17/20 2:44 AM, Anson Huang wrote:
> > Hi, Daniel
> >
> >
> >> Subject: Re: [PATCH 1/2] pinctrl: imx: Support building SCU pinctrl
> >> driver as module
> >>
> >> On 7/16/20 6:21 PM, Anson Huang wrote:
> >>> Hi, Daniel
> >>>
> >>>
> >>>> Subject: Re: [PATCH 1/2] pinctrl: imx: Support building SCU pinctrl
> >>>> driver as module
> >>>>
> >>>> Hi Anson,
> >>>>
> >>>> Few comments inline:
> >>>>
> >>>> On 7/16/20 6:06 PM, Anson Huang wrote:
> >>>>> To support building i.MX SCU pinctrl driver as module, below
> >>>>> things need to
> >>>> be changed:
> >>>>>        - Export SCU related functions and use "IS_ENABLED" instead of
> >>>>>          "ifdef" to support SCU pinctrl driver user and itself to be
> >>>>>          built as module;
> >>>>>        - Use function callbacks for SCU related functions in
> pinctrl-imx.c
> >>>>>          in order to support the scenario of PINCTRL_IMX is built in
> >>>>>          while PINCTRL_IMX_SCU is built as module;
> >>>>>        - All drivers using SCU pinctrl driver need to initialize the
> >>>>>          SCU related function callback;
> >>>>>        - Change PINCTR_IMX_SCU to tristate;
> >>>>>        - Add module author, description and license.
> >>>>>
> >>>>> With above changes, i.MX SCU pinctrl driver can be built as module.
> >>>> There are a lot of changes here. I think it would be better to try
> >>>> to split them
> >>>>
> >>>> per functionality. One functional change per patch.
> >>> Actually, I ever tried to split them, but the function will be broken.
> >>> All the changes are just to support the module build. If split them,
> >>> the bisect will have pinctrl build or function broken.
> >> Hi Anson,
> >>
> >>
> >> I see your point and I know that this is a very hard task to get it
> >> right from
> >>
> >> the first patches.
> >>
> >> But let me suggest at least that:
> >>
> >> - changes in  drivers/pinctrl/freescale/pinctrl-imx.c (include file
> >> and MODULE_ macros should go to a separate patch).
> > You meant in patch #2, the changes in Kconfig and the changes in .c
> > file should be split to 2 patches?
> 
> 
> No. I mean look at path #1.
> 
> The section above should be placed in a separate patch.
> 
>   static const struct of_device_id imx8qxp_pinctrl_of_match[] = { diff --git
> a/drivers/pinctrl/freescale/pinctrl-scu.c b/drivers/pinctrl/freescale/pinctrl-scu.c
> index 9df45d3..59b5f8a 100644
> --- a/drivers/pinctrl/freescale/pinctrl-scu.c
> +++ b/drivers/pinctrl/freescale/pinctrl-scu.c
> @@ -7,6 +7,7 @@
> 
>   #include <linux/err.h>
>   #include <linux/firmware/imx/sci.h>
> +#include <linux/module.h>
>   #include <linux/of_address.h>
>   #include <linux/pinctrl/pinctrl.h>
>   #include <linux/platform_device.h>
> @@ -123,3 +124,7 @@ void imx_pinctrl_parse_pin_scu(struct imx_pinctrl
> *ipctl,
>   		pin_scu->mux_mode, pin_scu->config);
>   }
>   EXPORT_SYMBOL_GPL(imx_pinctrl_parse_pin_scu);
> +
> +MODULE_AUTHOR("Dong Aisheng<aisheng.dong@xxxxxxx>");
> +MODULE_DESCRIPTION("NXP i.MX SCU common pinctrl driver");
> +MODULE_LICENSE("GPL v2");
> 
> 
> This can be in a separate patch.

I don't understand, without adding module license, changing the SCU pinctrl driver
to "tristate", when building with =M, the build will have warning as below, so I think
it does NOT make sense to split it to 2 patches.

  CC [M]  drivers/pinctrl/freescale/pinctrl-scu.o
  MODPOST Module.symvers
WARNING: modpost: missing MODULE_LICENSE() in drivers/pinctrl/freescale/pinctrl-scu.o
  LD [M]  drivers/pinctrl/freescale/pinctrl-scu.ko

Thanks,
Anson