[U-Boot] [RFC PATCH v2 0/6] Port of MUSB driver from Linux

Marek Vasut marex at denx.de
Sat Sep 22 02:55:26 CEST 2012

Dear Ilya Yanok,

> Current MUSB driver in U-Boot uses old UDC API while new gagdet
> client drivers need new gadget API. Also current MUSB driver has
> some significant limitations (like inability to handle tx for
> endpoints other than ep0). So I think port of new Linux driver is
> desirable.
> This is initial port, performed mostly by putting DM and OTG
> code under #ifndef __UBOOT__ clauses. My intention was to be as
> close as possible to the original to ease of possible resyncs.
> Some warnings are suppressed via CFLAGS. There are some style
> problems but I'm not touching them for now for the above mentioned
> reason. There is obviously some room for optimisation, some
> structure fields are unused as well as (probably) some code.
> This is not a replacement for existing MUSB driver (at least for
> now), cause there are still consumers of the old interface and
> the only ported backend is for TI AM335X (while the old code
> has a bunch of other backends).
> OTG and DMA are not supported. The only ported driver
> is for TI AM33xx, but others should be easy to port too.
> Virtual root hub is not implemented but this shouldn't be
> a big problem as the old code has virtual root hub support
> enabled only for Blackfin platform.
> Tested it on AM335x EVM and BeagleBone with CDC Ethernet gadget
> and a bunch of storage devices.
> Pathes are rather big because of the original code size (and I didn't
> delete unused code, just disabled it). So it's probably better to
> look at changes as compared to Linux code. I prepared such version
> also, you can find it at [1]. Hopefully it will be also useful
> if resync with the kernel will be needed in future.
> [1] https://github.com/yanok/u-boot/tree/musb-changes-from-linux

I'm glad about this. But how can we make this work if we already have a driver 
for this in u-boot, now we will have another. Tom ?

Best regards,
Marek Vasut

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