Re: [PATCH v3 6/8] usb: dwc2: host: Assume all devices are on one single_tt hub

From: Doug Anderson
Date: Tue Nov 17 2015 - 16:23:05 EST


On Mon, Nov 16, 2015 at 4:51 PM, Douglas Anderson <dianders@xxxxxxxxxxxx> wrote:
> Until we have logic to determine which devices share the same TT let's
> add logic to assume that all devices on a given dwc2 controller are on
> one single_tt hub. This is better than the previous code that assumed
> that all devices were on one multi_tt hub, since single_tt hubs
> appear (in my experience) to be much more common and any schedule that
> would work on a single_tt hub will also work on a multi_tt hub. This
> will prevent more than 8 total low/full speed devices to be on the bus
> at one time, but that's a reasonable restriction until we've made things
> smarter.
> Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
> ---
> Changes in v3:
> - Assuming single_tt is new for v3; not terribly well tested (yet).
> Changes in v2: None
> drivers/usb/dwc2/core.h | 1 +
> drivers/usb/dwc2/hcd_queue.c | 40 +++++++++++++++++++++++++++++++++++++++-
> 2 files changed, 40 insertions(+), 1 deletion(-)

Just as a FYI I managed to make this a little better with
<>, but not posting that yet because
Julius has pointed out some things offline that I could be doing
better (actually schedule the low speed bus properly). I'll hopefully
post something more soon...

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