Re: [PATCH v4 3/4] usb: dwc3: dwc3-generic-plat: Add layerscape dwc3 support

[Thinh Nguyen <Thinh.Nguyen@synopsys.com>]

On Fri, Sep 26, 2025, Frank Li via B4 Relay wrote:
> From: Frank Li <Frank.Li@nxp.com>
> 
> Add layerscape dwc3 support by using flatten dwc3 core library. Layerscape
> dwc3 need set gsbuscfg0-reqinfo as 0x2222 when dma-coherence set.
> 
> Signed-off-by: Frank Li <Frank.Li@nxp.com>
> ---
> chagne in v4
> - rename gsbuscfg0 to gsbuscfg0_reqinfo
> - use flatten core's properties.
> 
> change in v3 (skipped)
> ---
>  drivers/usb/dwc3/dwc3-generic-plat.c | 15 ++++++++++++++-
>  1 file changed, 14 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/dwc3/dwc3-generic-plat.c b/drivers/usb/dwc3/dwc3-generic-plat.c
> index af95a527dcc27a7a14d38dcc887f74a888ed91e6..cfcefeffd7ad6c0a21ccc9aaa4483b9acb9dc4e0 100644
> --- a/drivers/usb/dwc3/dwc3-generic-plat.c
> +++ b/drivers/usb/dwc3/dwc3-generic-plat.c
> @@ -8,6 +8,7 @@
>   */
>  
>  #include <linux/clk.h>
> +#include <linux/of_address.h>
>  #include <linux/platform_device.h>
>  #include <linux/reset.h>
>  #include "glue.h"
> @@ -29,6 +30,7 @@ static void dwc3_generic_reset_control_assert(void *data)
>  
>  static int dwc3_generic_probe(struct platform_device *pdev)
>  {
> +	const struct dwc3_properties *properties;
>  	struct dwc3_probe_data probe_data = {};
>  	struct device *dev = &pdev->dev;
>  	struct dwc3_generic *dwc3g;
> @@ -75,7 +77,13 @@ static int dwc3_generic_probe(struct platform_device *pdev)
>  	probe_data.dwc = &dwc3g->dwc;
>  	probe_data.res = res;
>  	probe_data.ignore_clocks_and_resets = true;
> -	probe_data.properties = DWC3_DEFAULT_PROPERTIES;
> +
> +	properties = of_device_get_match_data(dev);
> +	if (of_dma_is_coherent(pdev->dev.of_node) && properties)

Why do we need the check of_dma_is_coherent() here? Is this specific to
your platform to determine whether set gsbuscfg0_reqinfo only?

> +		probe_data.properties = *properties;
> +	else
> +		probe_data.properties = DWC3_DEFAULT_PROPERTIES;
> +
>  	ret = dwc3_core_probe(&probe_data);
>  	if (ret)
>  		return dev_err_probe(dev, ret, "failed to register DWC3 Core\n");
> @@ -146,8 +154,13 @@ static const struct dev_pm_ops dwc3_generic_dev_pm_ops = {
>  		       dwc3_generic_runtime_idle)
>  };
>  
> +static const struct dwc3_properties fsl_ls1028_dwc3 = {
> +	.gsbuscfg0_reqinfo = 0x2222,
> +};
> +
>  static const struct of_device_id dwc3_generic_of_match[] = {
>  	{ .compatible = "spacemit,k1-dwc3", },
> +	{ .compatible = "fsl,ls1028a-dwc3", &fsl_ls1028_dwc3},
>  	{ /* sentinel */ }
>  };
>  MODULE_DEVICE_TABLE(of, dwc3_generic_of_match);
> 
> -- 
> 2.34.1
> 
> 

BR,
Thinh