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* [PATCH] usb: dwc3: google: Initialise probe properties with DWC3_DEFAULT_PROPERTIES
@ 2026-08-19 18:21 Radhey Shyam Pandey
  2026-08-26  0:36 ` Thinh Nguyen
  0 siblings, 1 reply; 2+ messages in thread
From: Radhey Shyam Pandey @ 2026-08-19 18:21 UTC (permalink / raw)
  To: peter.griffin, andre.draszik, tudor.ambarus, Thinh.Nguyen, gregkh
  Cc: linux-arm-kernel, linux-samsung-soc, linux-usb, linux-kernel,
	Radhey Shyam Pandey

dwc3_google_probe() zero initialises struct dwc3_probe_data and never
assigns its properties member. The unspecified state of gsbuscfg0_reqinfo
is encoded as DWC3_GSBUSCFG0_REQINFO_UNSPECIFIED (0xffffffff), not as
zero, so dwc3_get_software_properties() reads the zeroed field as a value
the glue explicitly requested:

	if (properties->gsbuscfg0_reqinfo !=
	    DWC3_GSBUSCFG0_REQINFO_UNSPECIFIED) {
		dwc->gsbuscfg0_reqinfo = properties->gsbuscfg0_reqinfo;
		return;
	}

Two things follow. dwc3_config_soc_bus() programs GSBUSCFG0.REQINFO with
zero on hardware that never asked for it, and the early return skips the
walk over the parent devices, so a swnode or device tree supplied
snps,gsbuscfg0-reqinfo would be ignored.

Assign DWC3_DEFAULT_PROPERTIES so the unset fields carry their unspecified
sentinels and the controller is left alone.

Fixes: 8995a37371bf ("usb: dwc3: Add Google Tensor SoC DWC3 glue driver")
Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@amd.com>
---
 drivers/usb/dwc3/dwc3-google.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/usb/dwc3/dwc3-google.c b/drivers/usb/dwc3/dwc3-google.c
index 60ee4cc99b28..a01ca23cb6a8 100644
--- a/drivers/usb/dwc3/dwc3-google.c
+++ b/drivers/usb/dwc3/dwc3-google.c
@@ -442,6 +442,7 @@ static int dwc3_google_probe(struct platform_device *pdev)
 	probe_data.dwc = &google->dwc;
 	probe_data.res = res;
 	probe_data.ignore_clocks_and_resets = true;
+	probe_data.properties = DWC3_DEFAULT_PROPERTIES;
 	ret = dwc3_core_probe(&probe_data);
 	if (ret)  {
 		ret = dev_err_probe(dev, ret, "failed to register DWC3 Core\n");

base-commit: 6a746cd265aed59107ebdaa9ce039bb832922969
-- 
2.43.0


^ permalink raw reply related	[flat|nested] 2+ messages in thread

* Re: [PATCH] usb: dwc3: google: Initialise probe properties with DWC3_DEFAULT_PROPERTIES
  2026-08-19 18:21 [PATCH] usb: dwc3: google: Initialise probe properties with DWC3_DEFAULT_PROPERTIES Radhey Shyam Pandey
@ 2026-08-26  0:36 ` Thinh Nguyen
  0 siblings, 0 replies; 2+ messages in thread
From: Thinh Nguyen @ 2026-08-26  0:36 UTC (permalink / raw)
  To: Radhey Shyam Pandey
  Cc: peter.griffin@linaro.org, andre.draszik@linaro.org,
	tudor.ambarus@linaro.org, Thinh Nguyen,
	gregkh@linuxfoundation.org, linux-arm-kernel@lists.infradead.org,
	linux-samsung-soc@vger.kernel.org, linux-usb@vger.kernel.org,
	linux-kernel@vger.kernel.org

On Wed, Aug 19, 2026, Radhey Shyam Pandey wrote:
> dwc3_google_probe() zero initialises struct dwc3_probe_data and never
> assigns its properties member. The unspecified state of gsbuscfg0_reqinfo
> is encoded as DWC3_GSBUSCFG0_REQINFO_UNSPECIFIED (0xffffffff), not as
> zero, so dwc3_get_software_properties() reads the zeroed field as a value
> the glue explicitly requested:
> 
> 	if (properties->gsbuscfg0_reqinfo !=
> 	    DWC3_GSBUSCFG0_REQINFO_UNSPECIFIED) {
> 		dwc->gsbuscfg0_reqinfo = properties->gsbuscfg0_reqinfo;
> 		return;
> 	}
> 
> Two things follow. dwc3_config_soc_bus() programs GSBUSCFG0.REQINFO with
> zero on hardware that never asked for it, and the early return skips the
> walk over the parent devices, so a swnode or device tree supplied
> snps,gsbuscfg0-reqinfo would be ignored.
> 
> Assign DWC3_DEFAULT_PROPERTIES so the unset fields carry their unspecified
> sentinels and the controller is left alone.
> 
> Fixes: 8995a37371bf ("usb: dwc3: Add Google Tensor SoC DWC3 glue driver")

Does this need Cc stable?

Regardless,
Acked-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>

Thanks,
Thinh


> Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@amd.com>
> ---
>  drivers/usb/dwc3/dwc3-google.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/usb/dwc3/dwc3-google.c b/drivers/usb/dwc3/dwc3-google.c
> index 60ee4cc99b28..a01ca23cb6a8 100644
> --- a/drivers/usb/dwc3/dwc3-google.c
> +++ b/drivers/usb/dwc3/dwc3-google.c
> @@ -442,6 +442,7 @@ static int dwc3_google_probe(struct platform_device *pdev)
>  	probe_data.dwc = &google->dwc;
>  	probe_data.res = res;
>  	probe_data.ignore_clocks_and_resets = true;
> +	probe_data.properties = DWC3_DEFAULT_PROPERTIES;
>  	ret = dwc3_core_probe(&probe_data);
>  	if (ret)  {
>  		ret = dev_err_probe(dev, ret, "failed to register DWC3 Core\n");
> 
> base-commit: 6a746cd265aed59107ebdaa9ce039bb832922969
> -- 
> 2.43.0
> 

^ permalink raw reply	[flat|nested] 2+ messages in thread

end of thread, other threads:[~2026-08-26  0:36 UTC | newest]

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2026-08-19 18:21 [PATCH] usb: dwc3: google: Initialise probe properties with DWC3_DEFAULT_PROPERTIES Radhey Shyam Pandey
2026-08-26  0:36 ` Thinh Nguyen

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