Re: [PATCH v2] USB: Add MSM USB Device Controller driver

[Matthieu CASTET <matthieu.castet@parrot.com>]

Hi Pavan,

Pavan Kondeti a écrit :
> On Tue, Nov 09, 2010 at 12:40:17PM +0100, Matthieu CASTET wrote:
> 
> Hi Matthieu,
> 
>>>
>> This look like the arc/chipidea/mips ehci otg core.
> 
> Yes. It is chipidea core for ARM.
>> Why can't you reuse the ci13xxx_udc.c driver ?
>> Or if ci13xxx_udc.c is too bad, rewrite a new generic version for this core.
>>
> ci13xxx_udc.c driver registers with PCI subsytem (ours is a platform subsystem),
> does not manage clocks. msm72k_udc.c also takes care of initializing the
> integrated PHY. We also need to program special registers (MSM-ARM specific)
> upon resetting the hardware.
Yes, but why not adding this to ci13xxx_udc.c instead of doing a new driver.
For example adding platform subsystem is less than 150 lines of code.

I am not sure doing n drivers for a same hardware is a good idea.

May be ci13xxx_udc.c isn't enough generic, but in this case don't do the 
same mistake with the new driver.

Make a generic core, and make the ulpi stuff (or other specific stuff) 
in a glue around this code.

Look at host ehci : you don't need to rewrite ehci core. You only add a 
glue around it.


Matthieu