usb: do not reset if a low-speed device timed out

[Maxim Moseychuk <franchesko.salias.hudro.pedros@gmail.com>]

В Чт, 04/01/2018 в 11:57 -0500, Alan Stern пишет:
> On Thu, 4 Jan 2018, Maxim Moseychuk wrote:
> 
> > Some low-speed devices (for example, bluetooth) do not have
> > time to initialize. For them, ETIMEDOUT is a valid error.
> > We need to give them another try. Otherwise, they will
> > never be initialized correctly and in dmesg will be messages
> > "Bluetooth: hci0 command 0x1002 tx timeout" or similars.
> 
> Your patch description talks about low-speed devices...
> 
> > Fixes: 264904ccc33c ("usb: retry reset if a device times out")
> > Signed-off-by: Maxim Moseychuk <franchesko.salias.hudro.pedros@gmai
> l.com>
> > ---
> >  drivers/usb/core/hub.c | 5 ++++-
> >  1 file changed, 4 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
> > index cf7bbcb9a63c..46366c73f0df 100644
> > --- a/drivers/usb/core/hub.c
> > +++ b/drivers/usb/core/hub.c
> > @@ -4524,7 +4524,10 @@ hub_port_init(struct usb_hub *hub, struct
> usb_device *udev, int port1,
> >                                * reset. But only on the first
> attempt,
> >                                * lest we get into a time out/reset
> loop
> >                                */
> > -                             if (r == 0  || (r == -ETIMEDOUT &&
> retries == 0))
> > +                             if (r == 0 ||
> > +                                             r == -ETIMEDOUT
> > +                                             && retries == 0
> > +                                             && udev->speed >
> USB_SPEED_FULL)
> 
> but the patch itself affects both low-speed and full-speed devices.
> 
> Also, I would keep the parens around the && expressions, and there's
> no
> need for the first line break you added.  (For that matter, it looks
> strange to break the first line _after_ the || operator and then to
> break the later lines _before_ the && operators -- try to copy the 
> style used elsewhere in that source file.)
> 
> Alan Stern
> 

I probably chose the wrong term. We are talking about devices running
at speeds of usb 1.1 (Low-speed and Full-speed).
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