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

From: Sebastian Andrzej Siewior
Date: Tue Jul 23 2013 - 13:31:57 EST


On 07/23/2013 07:28 PM, Bin Liu wrote:
> Hi,

Hi,

>
> On Mon, Jul 22, 2013 at 1:10 PM, Sebastian Andrzej Siewior
> <bigeasy@xxxxxxxxxxxxx <mailto:bigeasy@xxxxxxxxxxxxx>> wrote:
>
> This patch adds the MUSB_DEVCTL_SESSION back after it has been removed.
> If it is missing then the host session is not recognized. This bit is
> added initially added in musb_start() and removed after the first device
> disconnect.
>
> AFAIK, after the device is disconnected, the OTG state machine will go
> back to B_IDLE/A_IDLE state. SESSION is not needed in this case.


Okay.

> In OTG mode, when no device is plugged, the ID pin is floating, you can
> never hold the host session in this case, even set the SESSION bit. The
> SESSION bit will be cleared by the controller after 100ms.

In my testing the bit remains set. How is the bit supposed to come back
after I connect a host device?

> Regards,
> -Bin.
>

Sebastian
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