Messages in this thread | | | Date | Thu, 16 Feb 2023 12:40:12 +0100 | From | Greg KH <> | Subject | Re: [PATCH] usb: gadget: Do not handle OS Descriptors config separately |
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On Mon, Feb 13, 2023 at 03:45:25PM -0800, Elson Roy Serrao wrote: > Consider a multi-configuration composition in which the last > configuration uses OS descriptors. Since this configuration will > be sent first, the host may choose this config if it matches the > choosing criteria and ignore the user configured order of the > multi-config composition.
That is up to the host, so why is this an issue?
> Moreover linux based hosts do not re-order > the received configurations based on their indices but process them > in FIFO order.
s/linux/Linux/
> This may result in the host never choosing the user > desired configuration because of the re-order caused by sending the > OS descriptor config first. To avoid this, follow the user configured > order and do not handle OS descriptor config separately.
I do not understand, what reordering is happening, and by whom?
> > Signed-off-by: Elson Roy Serrao <quic_eserrao@quicinc.com>
What commit does this fix?
> --- > drivers/usb/gadget/composite.c | 9 --------- > 1 file changed, 9 deletions(-) > > diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c > index fa7dd6c..685003a 100644 > --- a/drivers/usb/gadget/composite.c > +++ b/drivers/usb/gadget/composite.c > @@ -589,18 +589,9 @@ static int config_desc(struct usb_composite_dev *cdev, unsigned w_value) > w_value &= 0xff; > > pos = &cdev->configs; > - c = cdev->os_desc_config; > - if (c) > - goto check_config; > - > while ((pos = pos->next) != &cdev->configs) { > c = list_entry(pos, typeof(*c), list); > > - /* skip OS Descriptors config which is handled separately */ > - if (c == cdev->os_desc_config) > - continue; > - > -check_config:
This feels wrong, are you sure that this code isn't here for a reason? How did you test this?
thanks,
greg k-h
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