Re: [PATCH 14/16] usb: musb: dsps: add MUSB_DEVCTL_SESSION back afterremoval

From: Sebastian Andrzej Siewior
Date: Fri Jul 26 2013 - 14:23:16 EST

On 07/26/2013 08:17 PM, Bin Liu wrote:

Hi Bin.

>> In TI 3.2 kernel, the otg_timer() toggles the SESSION bit in
>> OTG_STATE_B_IDLE state. So whenever the ID pin is grounded by
>> connecting a device, the controller will try go into host mode.
>> But I have no idea why your board is in a_idle not b_idle. The toggle
>> does not handle a_idle.
>> Do you use the AM335x GP EVM, not the smaller StarterKit EVM, right?
>> the USB0 port on SK EVM is device only.
>> But anyway, I have not seen any use case which uses micro-AB
>> receptacle and requires such dynamic role switching. So I kind of
> I meant the real customer use cases, not the EVMs ;)
I am using the about the second port on am335x evm which is used as
host (not OTG mode (3) but HOST (1)). If I start the timer OTG after
disconnect I see that it gets back to A mode:

[ 97.570852] musb-hdrc Poll devctl 19 (a_wait_bcon)
[ 99.570306] musb-hdrc Poll devctl 98 (a_idle)

[ 209.570259] musb-hdrc Poll devctl 80 (a_idle)

and now the session bit is missing and never gets back so I can not
plug any other device. I really have no idea what is missing here…

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