RE: [PATCH V4 3/5] clk: imx: Support building i.MX common clock driver as module

From: Anson Huang
Date: Thu Jul 02 2020 - 02:42:37 EST




> Subject: Re: [PATCH V4 3/5] clk: imx: Support building i.MX common clock
> driver as module
>
> On Thu, Jul 2, 2020 at 2:11 PM Anson Huang <anson.huang@xxxxxxx> wrote:
> >
> > > Subject: Re: [PATCH V4 3/5] clk: imx: Support building i.MX common
> > > clock driver as module
> > >
> > > On Thu, Jul 2, 2020 at 11:26 AM Anson Huang <anson.huang@xxxxxxx>
> > > wrote:
> > > [...]
> > > > > > @@ -143,16 +148,18 @@ void imx_cscmr1_fixup(u32 *val) static
> > > > > > int imx_keep_uart_clocks; static struct clk ** const
> > > > > > *imx_uart_clocks;
> > > > > >
> > > > > > -static int __init imx_keep_uart_clocks_param(char *str)
> > > > > > +static int __maybe_unused imx_keep_uart_clocks_param(char
> > > > > > +*str)
> > > > > > {
> > > > > > imx_keep_uart_clocks = 1;
> > > > > >
> > > > > > return 0;
> > > > > > }
> > > > > > +#ifndef MODULE
> > > > > > __setup_param("earlycon", imx_keep_uart_earlycon,
> > > > > > imx_keep_uart_clocks_param, 0);
> > > > > > __setup_param("earlyprintk", imx_keep_uart_earlyprintk,
> > > > > > imx_keep_uart_clocks_param, 0);
> > > > >
> > > > > I feel not only the __setup_param, the whole logic of
> > > > > keep_uart_clocks are not needed for Module case. Is it true?
> > > >
> > > > Yes, but the 'keep_uart_clocks' is false by default and the
> > > > function
> > > > imx_keep_uart_clocks_param() already has '__maybe_unused', it does
> > > > NOT impact anything if it is for module build, so I did NOT add
> > > > the #ifndef check
> > > for them, just to keep code easy and clean.
> > > >
> > >
> > > IMHO do not compile them is a more easy and clean way. Then users
> > > don't have to look into the code logic which is meaingless for Module case.
> > >
> > > BTW, it really does not make any sense to only condionally compile
> > > __setup_parm() but left
> > > the param functions definition to be handled by __maybe_unnused.
> > > They're together part of code, aren't they?
> >
> > I am fine of adding the '#ifndef MODULE' to imx_clk_disable_uart() and
> > imx_keep_uart_clocks_param() as well in next patch series. Others like
> > ' imx_keep_uart_clocks ' and imx_register_uart_clocks() need to be kept
> always built, since they are used by each clock driver no matter built-in or
> module build.
> >
> > So that means I have to add another 'ifndef MODULE' or I need to
> > adjust some code sequence to make those code can be built-out in same
> > block and just use single 'ifndef MODULE', I think adjust the code sequence
> should be better, will go with this way.
>
> What if we condionally compile it in clk.h? Will that be easiser?

Adjust the function sequence looks like NOT complicated, just need to exchange the
imx_register_uart_clocks() and imx_clk_disable_uart(), then I can use single '#ifndef MODULE',
will go with this way in V5.

Anson