Re: Nokia N900: musb is in wrong state after boot

From: Sergei Shtylyov
Date: Wed Jun 08 2016 - 08:32:32 EST


On 6/8/2016 3:18 PM, joerg Reisenweber wrote:

Tony, what do you think about that patch?

Tony, PING

Yeah I don't know, AFAIK we don't have a generic way to
force MUSB to change mode without ID pin. If you have figured
something generic for that which does not actually tinker with
the PHY registers directly, that should be the generic
musb_set_mode() that we've been wondering about for years.

#define MUSB_TEST_FORCE_HOST 0x80

Can someone confirm on MUSB's docs (and actual running system) that this
does what's supposed to do?

The MUSB programmer's guide says the CID (sic) input is ignored when the
Force_Host bit is set. The host mode is entered when the Session bit is
set. But I don't have a MUSB hardware readily available to confirm.

MBR, Sergei

also says:

While the FORCE_HOST bit remains set, the core will enter Host mode when the
Session bit is set and **remain in Host mode until the Session bit is cleared
even if a connected device is disconnected during the session.**
The operating speed while in this mode **is determined for the setting of the
FORCE_HS and FORCE_FS bits of the Testmode register** in Section 23.1.4.11.

Yeah, the MUSB PG says the same.

[...]

/j

MBR, Sergei