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.
> + else
> + priv->init_type = plat->init_type;
> + }
> +
> #if CONFIG_IS_ENABLED(DM_REGULATOR)
> ret = device_get_supply_regulator(dev, "vbus-supply",
> &priv->vbus_supply);
> diff --git a/include/usb.h b/include/usb.h
> index b3851fdb4f..47d738a786 100644
> --- a/include/usb.h
> +++ b/include/usb.h
> @@ -163,7 +163,8 @@ struct int_queue;
> */
> enum usb_init_type {
> USB_INIT_HOST,
> - USB_INIT_DEVICE
> + USB_INIT_DEVICE,
> + USB_INIT_UNKNOWN,
> };
>
> /**********************************************************************
