[PATCH v2] usb: gadget: fsl: Re-enable driver for ARM SoCs

[Greg KH]

On Fri, Jun 11, 2021 at 02:11:27AM +0000, Leo Li wrote:
> 
> 
> > -----Original Message-----
> > From: Joel Stanley <joel at jms.id.au>
> > Sent: Thursday, June 10, 2021 9:01 PM
> > To: Fabio Estevam <festevam at gmail.com>; Peter Chen
> > <peter.chen at nxp.com>; Arnd Bergmann <arnd at arndb.de>; Felipe Balbi
> > <balbi at kernel.org>; Shawn Guo <shawnguo at kernel.org>; Leo Li
> > <leoyang.li at nxp.com>; dl-linux-imx <linux-imx at nxp.com>; Stephen
> > Rothwell <sfr at canb.auug.org.au>
> > Cc: linux-usb at vger.kernel.org; Linux ARM <linux-arm-
> > kernel at lists.infradead.org>
> > Subject: Re: [PATCH v2] usb: gadget: fsl: Re-enable driver for ARM SoCs
> > 
> > On Thu, 10 Jun 2021 at 03:50, Joel Stanley <joel at jms.id.au> wrote:
> > >
> > > The commit a390bef7db1f ("usb: gadget: fsl_mxc_udc: Remove the
> > > driver") dropped the ARCH_MXC dependency from USB_FSL_USB2,
> > leaving it
> > > depending solely on FSL_SOC.
> > >
> > > FSL_SOC is powerpc only; it was briefly available on ARM in 2014 but
> > > was removed by commit cfd074ad8600 ("ARM: imx: temporarily remove
> > > CONFIG_SOC_FSL from LS1021A"). Therefore the driver can no longer be
> > > enabled on ARM platforms.
> > >
> > > This appears to be a mistake as arm64's ARCH_LAYERSCAPE and arm32
> > > SOC_LS1021A SoCs use this symbol. It's enabled in these defconfigs:
> > >
> > > arch/arm/configs/imx_v6_v7_defconfig:CONFIG_USB_FSL_USB2=y
> > > arch/arm/configs/multi_v7_defconfig:CONFIG_USB_FSL_USB2=y
> > > arch/powerpc/configs/mgcoge_defconfig:CONFIG_USB_FSL_USB2=y
> > > arch/powerpc/configs/mpc512x_defconfig:CONFIG_USB_FSL_USB2=y
> > >
> > > To fix, expand the dependencies so USB_FSL_USB2 can be enabled on the
> > > ARM platforms, and with COMPILE_TEST.
> > 
> > This didn't work out, as there's some missing clock initialisation calls that were
> > removed when fsl_mxc_udc was deleted:
> > 
> > arm-linux-gnueabi-ld: drivers/usb/gadget/udc/fsl_udc_core.o: in function
> > `fsl_udc_remove':
> > fsl_udc_core.c:(.text+0xc88): undefined reference to `fsl_udc_clk_release'
> > arm-linux-gnueabi-ld: drivers/usb/gadget/udc/fsl_udc_core.o: in function
> > `fsl_udc_probe':
> > fsl_udc_core.c:(.text+0x1c44): undefined reference to `fsl_udc_clk_init'
> > arm-linux-gnueabi-ld: fsl_udc_core.c:(.text+0x1dcc): undefined reference to
> > `fsl_udc_clk_finalize'
> > arm-linux-gnueabi-ld: fsl_udc_core.c:(.text+0x1fe8): undefined reference to
> > `fsl_udc_clk_release'
> > 
> > We could add them back, but it's not clear if this driver is still maintained. I'm
> > looking to the NXP people for input here.
> 
> Adding Ran Wang to the loop.  I think we will maintain the driver to keep the legacy platforms working but will not add new users of this driver.

Now reverted in my tree.

thanks,

greg k-h