Re: [PATCH v3 2/8] usb: dwc2: Fix incorrect ULPI_UTMI_SEL bit setting

[Mattijs Korpershoek <mkorpershoek@baylibre.com>]

Hi Junhui,

Thank you for the patch.

On sam., janv. 04, 2025 at 11:37, Junhui Liu <junhui.liu@pigmoral.tech> wrote:

> The ULPI_UTMI_SEL bit in the DWC2 driver was set incorrectly. According
> to the datasheet [1], this bit should be set to 0 for UTMI interface and 1
> for ULPI interface. The existing code had this logic reversed,
> causing the interface selection to be incorrect.
>
> This commit corrects the ULPI_UTMI_SEL bit setting to match the
> datasheet's description. Referencing the kernel's code [2] also confirms
> this fix.
>
> [1] https://rockchip.fr/RK312X%20TRM/chapter-26-usb-otg-2-0.pdf#page=30
> [2] https://github.com/torvalds/linux/blob/v6.13-rc3/drivers/usb/dwc2/core.c#L1106
>
> Reviewed-by: Marek Vasut <marex@denx.de>
> Tested-by: Peter Robinson <pbrobinson@gmail.com>
> Signed-off-by: Junhui Liu <junhui.liu@pigmoral.tech>

Reviewed-by: Mattijs Korpershoek <mkorpershoek@baylibre.com>

> ---
>  drivers/usb/host/dwc2.c | 24 +++++++++++++-----------
>  1 file changed, 13 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/usb/host/dwc2.c b/drivers/usb/host/dwc2.c
> index b6c8b3d5a6bdf375f1adeb106d4832d92307f0db..609de18faa3abc5f4ecb0c23cf3590966bad7992 100644
> --- a/drivers/usb/host/dwc2.c
> +++ b/drivers/usb/host/dwc2.c
> @@ -402,20 +402,22 @@ static void dwc_otg_core_init(struct udevice *dev)
>  	 * soft reset so only program the first time. Do a soft reset
>  	 * immediately after setting phyif.
>  	 */
> -	usbcfg &= ~(DWC2_GUSBCFG_ULPI_UTMI_SEL | DWC2_GUSBCFG_PHYIF);
> -	usbcfg |= DWC2_PHY_TYPE << DWC2_GUSBCFG_ULPI_UTMI_SEL_OFFSET;
> -
> -	if (usbcfg & DWC2_GUSBCFG_ULPI_UTMI_SEL) {	/* ULPI interface */
> +#if (DWC2_PHY_TYPE == DWC2_PHY_TYPE_ULPI)
> +	usbcfg |= DWC2_GUSBCFG_ULPI_UTMI_SEL;
> +	usbcfg &= ~DWC2_GUSBCFG_PHYIF;
>  #ifdef DWC2_PHY_ULPI_DDR
> -		usbcfg |= DWC2_GUSBCFG_DDRSEL;
> +	usbcfg |= DWC2_GUSBCFG_DDRSEL;
>  #else
> -		usbcfg &= ~DWC2_GUSBCFG_DDRSEL;
> -#endif
> -	} else {	/* UTMI+ interface */
> +	usbcfg &= ~DWC2_GUSBCFG_DDRSEL;
> +#endif /* DWC2_PHY_ULPI_DDR */
> +#elif (DWC2_PHY_TYPE == DWC2_PHY_TYPE_UTMI)
> +	usbcfg &= ~DWC2_GUSBCFG_ULPI_UTMI_SEL;
>  #if (DWC2_UTMI_WIDTH == 16)
> -		usbcfg |= DWC2_GUSBCFG_PHYIF;
> -#endif
> -	}
> +	usbcfg |= DWC2_GUSBCFG_PHYIF;
> +#else
> +	usbcfg &= ~DWC2_GUSBCFG_PHYIF;
> +#endif /* DWC2_UTMI_WIDTH */
> +#endif /* DWC2_PHY_TYPE */
>  
>  	writel(usbcfg, &regs->global_regs.gusbcfg);
>  
>
> -- 
> 2.47.1