Subject: Re: [PATCH v2 3/4] usb: dwc3: xilinx: Add Versal2 MMI USB 3.2 controller support

From: Thinh Nguyen <[email-masked]>
Date: Fri, 17 Apr 2026 23:53:20 +0000

On Tue, Mar 31, 2026, Radhey Shyam Pandey wrote:
> Multi-media integrated (MMI) USB3.2 DRD IP is usb3.1 gen2 controller
> which support following speed SSP (10-Gbps), SuperSpeed(5-Gbps),
> high-speed(480-Mbps), full-speed(12-Mbps), and low-speed(1.5-Mbps)
> operation modes.
> 
> USB2 and USB3 PHY support Physical connectivity via the Type-C
> connectivity. The MMI USB controller does not have a dedicated wrapper
> register space, so ioremap is skipped via the map_resource config flag.
> 
> The driver handles clock and reset initialization. In this initial
> version typec reversibility is not implemented and it is assumed that
> USB3 PHY TCA mux programming is done by MMI configuration data object
> (CDOs) and TI PD controller is configured using external tiva programmer
> on VEK385 evaluation board.
> 
> Tested host mode with mass storage device.
> 
> Signed-off-by: Radhey Shyam Pandey <[email-masked]>
> ---
> - Introduce xlnx,usb-syscon phandle to access UDH address space
>   which is wrapper subsystem IP for USB, DP and HDCP.

Where's xlnx,usb-syscon phandle?

> - Split config struct refactoring into separate patch (2/4).
> - Remove unused regmap/syscon fields and parsing code; defer to
>   patch that first consumes them.
> - Fix error message capitalization to lowercase ("reset", "deassert").
> ---
>  drivers/usb/dwc3/dwc3-xilinx.c | 50 ++++++++++++++++++++++++++++++----
>  1 file changed, 44 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/usb/dwc3/dwc3-xilinx.c b/drivers/usb/dwc3/dwc3-xilinx.c
> index bb59b56726e7..f2dee28bdc65 100644
> --- a/drivers/usb/dwc3/dwc3-xilinx.c
> +++ b/drivers/usb/dwc3/dwc3-xilinx.c
> @@ -46,6 +46,7 @@ struct dwc3_xlnx;
>  
>  struct dwc3_xlnx_config {
>  	int				(*pltfm_init)(struct dwc3_xlnx *data);
> +	bool				map_resource;

Perhaps this property should be inversed since the versal2 is unusual
that it doesn't need mapping of resource. How about no_mem_map?

>  };
>  
>  struct dwc3_xlnx {
> @@ -93,6 +94,29 @@ static void dwc3_xlnx_set_coherency(struct dwc3_xlnx *priv_data, u32 coherency_o
>  	}
>  }
>  
> +static int dwc3_xlnx_init_versal2(struct dwc3_xlnx *priv_data)
> +{
> +	struct device		*dev = priv_data->dev;
> +	struct reset_control	*crst;
> +	int			ret;
> +
> +	crst = devm_reset_control_get_optional_exclusive(dev, NULL);
> +	if (IS_ERR(crst))
> +		return dev_err_probe(dev, PTR_ERR(crst),
> +				     "failed to get reset signal\n");
> +
> +	/* assert and deassert reset */
> +	ret = reset_control_assert(crst);
> +	if (ret < 0)
> +		return dev_err_probe(dev, ret, "failed to assert reset\n");

Any requirement on how long the reset needs to stay asserted?

> +
> +	ret = reset_control_deassert(crst);
> +	if (ret < 0)
> +		return dev_err_probe(dev, ret, "failed to deassert reset\n");
> +
> +	return 0;
> +}
> +
>  static int dwc3_xlnx_init_versal(struct dwc3_xlnx *priv_data)
>  {
>  	struct device		*dev = priv_data->dev;
> @@ -250,10 +274,16 @@ static int dwc3_xlnx_init_zynqmp(struct dwc3_xlnx *priv_data)
>  
>  static const struct dwc3_xlnx_config zynqmp_config = {
>  	.pltfm_init = dwc3_xlnx_init_zynqmp,
> +	.map_resource = true,
>  };
>  
>  static const struct dwc3_xlnx_config versal_config = {
>  	.pltfm_init = dwc3_xlnx_init_versal,
> +	.map_resource = true,
> +};
> +
> +static const struct dwc3_xlnx_config versal2_config = {
> +	.pltfm_init = dwc3_xlnx_init_versal2,
>  };
>  
>  static const struct of_device_id dwc3_xlnx_of_match[] = {
> @@ -265,6 +295,10 @@ static const struct of_device_id dwc3_xlnx_of_match[] = {
>  		.compatible = "xlnx,versal-dwc3",
>  		.data = &versal_config,
>  	},
> +	{
> +		.compatible = "xlnx,versal2-mmi-dwc3",
> +		.data = &versal2_config,
> +	},
>  	{ /* Sentinel */ }
>  };
>  MODULE_DEVICE_TABLE(of, dwc3_xlnx_of_match);
> @@ -299,19 +333,23 @@ static int dwc3_xlnx_probe(struct platform_device *pdev)
>  	struct dwc3_xlnx		*priv_data;
>  	struct device			*dev = &pdev->dev;
>  	struct device_node		*np = dev->of_node;
> -	void __iomem			*regs;
>  	int				ret;
>  
>  	priv_data = devm_kzalloc(dev, sizeof(*priv_data), GFP_KERNEL);
>  	if (!priv_data)
>  		return -ENOMEM;
>  
> -	regs = devm_platform_ioremap_resource(pdev, 0);
> -	if (IS_ERR(regs))
> -		return dev_err_probe(dev, PTR_ERR(regs), "failed to map registers\n");
> -
>  	priv_data->dwc3_config = device_get_match_data(dev);
> -	priv_data->regs = regs;
> +
> +	if (priv_data->dwc3_config->map_resource) {
> +		void __iomem *regs;
> +
> +		regs = devm_platform_ioremap_resource(pdev, 0);
> +		if (IS_ERR(regs))
> +			return dev_err_probe(dev, PTR_ERR(regs),
> +					     "failed to map registers\n");
> +		priv_data->regs = regs;
> +	}
>  	priv_data->dev = dev;
>  
>  	platform_set_drvdata(pdev, priv_data);
> -- 
> 2.43.0
> 

BR,
Thinh