Re: [PATCH V3 04/10] clk: imx: Support building SCU clock driver as module

[Arnd Bergmann]

On Wed, Jul 1, 2020 at 9:19 AM Anson Huang <anson.huang@xxxxxxx> wrote:
> > Subject: Re: [PATCH V3 04/10] clk: imx: Support building SCU clock driver as module
> > On Tue, Jun 30, 2020 at 5:16 AM Anson Huang <anson.huang@xxxxxxx> wrote:
> >
> > SCU clock driver is a common driver for all SCU based platforms.
> > Current i.MX8QXP SCU clock driver will be extended to support all future SCU
> > based platforms.
> > So theoretically clk-scu.o and clk-imx8qxp.o can be combined. LPCG  is
> > similar.
> > Maybe you can give a try as Arnd suggested.
> >
>
> Do we really need to link clk-scu and i.MX8QXP clock driver together just to avoid some export?

It was just meant to be easier than exporting a symbol and dealing with module
dependencies. If it's not easier, then don't.

> I met some build issues if using this method, the i.MX8QXP module build is OK, but other platforms
> like i.MX8MM/i.MX8MN/i.MX8MQ/i.MX8MP clock drivers are just skipped for build, even these
> i.MX8M clock config are existing in .config, anyone know why? Looks like the change in Makefile for
> i.MX8QXP clock driver introduce this issue.

You have a ":=" instead of "+=" typo, so all earlier "+=" are ignored:

> obj-$(CONFIG_CLK_IMX8MM) += clk-imx8mm.o
> obj-$(CONFIG_CLK_IMX8MN) += clk-imx8mn.o
> obj-$(CONFIG_CLK_IMX8MP) += clk-imx8mp.o
> obj-$(CONFIG_CLK_IMX8MQ) += clk-imx8mq.o
>
> obj-$(CONFIG_MXC_CLK_SCU) := clk-imx-scu.o clk-imx-lpcg-scu.o

                                   ^^^^^^^^

      Arnd