Re: [PATCH 2/2] usb: gadget: aspeed: fixup usb1 device descriptor at init time

[Tao Ren]

On Thu, Feb 20, 2020 at 12:39:45PM +1100, Benjamin Herrenschmidt wrote:
> On Tue, 2020-02-18 at 15:56 -0800, rentao.bupt@xxxxxxxxx wrote:
> > From: Tao Ren <rentao.bupt@xxxxxxxxx>
> > 
> > This patch moves fixup-usb1-device-descriptor logic from get_descriptor
> > handler to "ast_vhub_fixup_dev_desc" function so the device descriptor
> > is only patched once (at vhub init time).
> 
> I don't like this either. We should make ast_vhub_dev_desc and patch a
> copy here too. I know today there's only one instance of the vhub in a
> given SoC but that might not always be the case.

Sure. I will introduce per-hub descripor instances in patch v2.


Cheers,

Tao
> 
> > Signed-off-by: Tao Ren <rentao.bupt@xxxxxxxxx>
> > ---
> >  drivers/usb/gadget/udc/aspeed-vhub/hub.c | 20 +++++++++-----------
> >  1 file changed, 9 insertions(+), 11 deletions(-)
> > 
> > diff --git a/drivers/usb/gadget/udc/aspeed-vhub/hub.c b/drivers/usb/gadget/udc/aspeed-vhub/hub.c
> > index 4e3ef83283a6..b8bf54b12adc 100644
> > --- a/drivers/usb/gadget/udc/aspeed-vhub/hub.c
> > +++ b/drivers/usb/gadget/udc/aspeed-vhub/hub.c
> > @@ -76,13 +76,6 @@ static struct usb_device_descriptor ast_vhub_dev_desc = {
> >  	.bNumConfigurations	= 1,
> >  };
> >  
> > -/* Patches to the above when forcing USB1 mode */
> > -static void ast_vhub_patch_dev_desc_usb1(struct usb_device_descriptor *desc)
> > -{
> > -	desc->bcdUSB = cpu_to_le16(0x0100);
> > -	desc->bDeviceProtocol = 0;
> > -}
> > -
> >  /*
> >   * Configuration descriptor: same comments as above
> >   * regarding handling USB1 mode.
> > @@ -316,10 +309,6 @@ static int ast_vhub_rep_desc(struct ast_vhub_ep *ep,
> >  	if (len > dsize)
> >  		len = dsize;
> >  
> > -	/* Patch it if forcing USB1 */
> > -	if (desc_type == USB_DT_DEVICE && ep->vhub->force_usb1)
> > -		ast_vhub_patch_dev_desc_usb1(ep->buf);
> > -
> >  	/* Shoot it from the EP buffer */
> >  	return ast_vhub_reply(ep, NULL, len);
> >  }
> > @@ -878,6 +867,15 @@ static void ast_vhub_fixup_dev_desc(struct ast_vhub *vhub)
> >  		if (of_str[id])
> >  			ast_vhub_str_array[i].s = of_str[id];
> >  	}
> > +
> > +	/*
> > +	 * Update USB Release Number and Protocol code if vhub is running
> > +	 * at USB 1.x speed.
> > +	 */
> > +	if (vhub->force_usb1) {
> > +		ast_vhub_dev_desc.bcdUSB = cpu_to_le16(0x0100);
> > +		ast_vhub_dev_desc.bDeviceProtocol = 0;
> > +	}
> >  }
> >  
> >  void ast_vhub_init_hub(struct ast_vhub *vhub)
>