Re: [PATCH] usb: xhci: bInterval quirk for TI TUSB73x0
From: Roger Quadros
Date: Fri Mar 10 2017 - 11:04:50 EST
On 09/03/17 11:44, Sergei Shtylyov wrote:
> On 3/9/2017 11:47 AM, Roger Quadros wrote:
>> As per  issue #4,
>> "The periodic EP scheduler always tries to schedule the EPs
>> that have large intervals (interval equal to or greater than
>> 128 microframes) into different microframes. So it maintains
>> an internal counter and increments for each large interval
>> EP added. When the counter is greater than 128, the scheduler
>> rejects the new EP. So when the hub re-enumerated 128 times,
>> it trigged this condition."
Should be "triggers" actually.
Will fix it. Thanks.
>> This results in Bandwidth error when devices with periodic
>> endpoints (ISO/INT) having bInterval > 7 are plugged an
>> unplugged several times on a TUSB73x0 xhci host.
>> Workaround this issue by limiting the bInterval to 7
>> (i.e. interval to 6) for High-speed or faster periodic endpoints.
>>  - http://www.ti.com/lit/er/sllz076/sllz076.pdf
>> Signed-off-by: Roger Quadros <rogerq@xxxxxx>
> MBR, Sergei