Re: [PATCH v11 4/5] usb: dwc3: dwc3-qcom: Enable tx-fifo-resize property by default

From: Greg KH
Date: Fri Jul 02 2021 - 04:19:53 EST


On Fri, Jul 02, 2021 at 01:10:13AM -0700, Wesley Cheng wrote:
>
>
> On 7/1/2021 10:06 PM, Greg KH wrote:
> > On Wed, Jun 30, 2021 at 02:00:41AM -0700, Wesley Cheng wrote:
> >> In order to take advantage of the TX fifo resizing logic, manually add
> >> these properties to the DWC3 child node by default. This will allow
> >> the DWC3 gadget to resize the TX fifos for the IN endpoints, which
> >> help with performance.
> >>
> >> Signed-off-by: Wesley Cheng <wcheng@xxxxxxxxxxxxxx>
> >> ---
> >> drivers/usb/dwc3/dwc3-qcom.c | 21 +++++++++++++++++++++
> >> 1 file changed, 21 insertions(+)
> >>
> >> diff --git a/drivers/usb/dwc3/dwc3-qcom.c b/drivers/usb/dwc3/dwc3-qcom.c
> >> index 49e6ca9..cec4f4a 100644
> >> --- a/drivers/usb/dwc3/dwc3-qcom.c
> >> +++ b/drivers/usb/dwc3/dwc3-qcom.c
> >> @@ -640,6 +640,25 @@ static int dwc3_qcom_acpi_register_core(struct platform_device *pdev)
> >> return ret;
> >> }
> >>
> >> +#ifdef CONFIG_OF
> >> +static void dwc3_qcom_add_dt_props(struct device *dev, struct device_node *np)
> >> +{
> >> + struct property *prop;
> >> + int ret;
> >> +
> >> + prop = devm_kzalloc(dev, sizeof(*prop), GFP_KERNEL);
> >> + if (prop) {
> >> + prop->name = "tx-fifo-resize";
> >> + ret = of_add_property(np, prop);
> >> + if (ret < 0)
> >> + dev_info(dev, "unable to add tx-fifo-resize prop\n");
>
> Hi Greg,
> >
> > Is that really an "informational" error? :(
> >
> >
> We can remove it. If anything we can always check the sysfs if the
> property is present or not.

Sorry for being vague. That message should be dev_err(), and not
dev_info(), right?

> >> + }
> >
> > So if you can not allocate memory, you just fail quietly? Are you sure
> > that is ok?
> >
> > Please properly handle errors.
> >
> OK, will handle the case where we can't allocate memory for the property.

And the case for when of_add_property() fails.

thanks,

greg k-h