On Tue, Jan 25, 2022 at 12:44 AM Marcel Ziswiler
<marcel.ziswi...@toradex.com> wrote:
>
> On Mon, 2022-01-17 at 18:21 -0600, Adam Ford wrote:
> > The imx8mm and imx8mn appear compatible with imx7d-usb
> > flags in the OTG driver. If the dr_mode is defined as
> > host or peripheral, the device appears to operate correctly,
> > however the auto host/peripheral detection results in an error.
> >
> > The solution isn't just adding checks for imx8mm and imx8mn to
> > the check for imx7, because the USB clock needs to be running
> > to read from the USBNC_PHY_STATUS_OFFSET register or it will hang.
> >
> > Marek requested that I not enable the clocks in ehci_usb_of_to_plat,
> > so I modified that function to return an unknown state if the
> > device tree does not explicitly state whether it is a host
> > or a peripheral.
> >
> > When the driver probes, it looks to see if it's in the unknown
> > state, and only then will it read the register to auto-detect.
> >
> > Signed-off-by: Adam Ford <aford...@gmail.com>
> > ---
> > V3: Keep ehci_usb_of_to_plat but add the ability to return
> > and unknown state instead of reading the register.
> > If the probe determines the states is unknown, it will
> > query the register after the clocks have been enabled.
> > Because of the slight behavior change, I removed any
> > review or tested tags.
> >
> > V2: Rename ehci_usb_of_to_plat to ehci_usb_dr_mode and call it
> > from the probe after the clocks are enabled, but before
> > the data is needed.
> >
> > diff --git a/drivers/usb/host/ehci-mx6.c b/drivers/usb/host/ehci-mx6.c
> > index 1bd6147c76..cf44e53ff7 100644
> > --- a/drivers/usb/host/ehci-mx6.c
> > +++ b/drivers/usb/host/ehci-mx6.c
> > @@ -543,7 +543,7 @@ static int ehci_usb_phy_mode(struct udevice *dev)
> > plat->init_type = USB_INIT_DEVICE;
> > else
> > plat->init_type = USB_INIT_HOST;
> > - } else if (is_mx7()) {
> > + } else if (is_mx7() || is_imx8mm() || is_imx8mn()) {
> > phy_status = (void __iomem *)(addr +
> > USBNC_PHY_STATUS_OFFSET);
> > val = readl(phy_status);
> > @@ -573,9 +573,8 @@ static int ehci_usb_of_to_plat(struct udevice *dev)
> > case USB_DR_MODE_PERIPHERAL:
> > plat->init_type = USB_INIT_DEVICE;
> > break;
> > - case USB_DR_MODE_OTG:
> > - case USB_DR_MODE_UNKNOWN:
> > - return ehci_usb_phy_mode(dev);
> > + default:
> > + plat->init_type = USB_INIT_UNKNOWN;
> > };
> >
> > return 0;
> > @@ -677,6 +676,20 @@ static int ehci_usb_probe(struct udevice *dev)
> > mdelay(1);
> > #endif
> >
> > + /*
> > + * If the device tree didn't specify host or device,
> > + * the default is USB_INIT_UNKNOWN, so we need to check
> > + * the register. For imx8mm and imx8mn, the clocks need to be
> > + * running first, so we defer the check until they are.
> > + */
> > + if (priv->init_type == USB_INIT_UNKNOWN) {
> > + ret = ehci_usb_phy_mode(dev);
> > + if (ret)
> > + goto err_clk;
>
> Hm, unfortunately, that label is gated by an ifdef leading to the following
> on colibri_imx7:
>
> drivers/usb/host/ehci-mx6.c: In function ‘ehci_usb_probe’:
> drivers/usb/host/ehci-mx6.c:688:4: error: label ‘err_clk’ used but not defined
> 688 | goto err_clk;
> | ^~~~
> make[1]: *** [scripts/Makefile.build:254: drivers/usb/host/ehci-mx6.o] Error 1
>
> I have to admit that maybe we should indeed run it with DM_REGULATOR but that
> won't change anything on this
> issue. I guess one should really not have any gotos to a label err_clk being
> ifdefed from somewhere not
> ifdefed.
>
Adam,
Can you re-submit this with an ifdef to handle the correct goto when
DM_REGULATOR is undefined?
It looks like Fabio figured out his issue with his board and it was
unrelated to this (fixed by 'mmc: fsl_esdhc_imx: fix watermark level
in dma') so I think Marcel's point is the only blocker on this patch
unless there is more discussion needed with Michael or some feedback
needed from Marek?
Best regards,
Tim
