[PATCH v2] davinci: DA850 EVM: OHCI platform code

Sergei Shtylyov sshtylyov at mvista.com
Wed Dec 21 07:24:49 EST 2011


On 21-12-2011 16:05, I wrote:

>> On Wed, Dec 21, 2011 at 12:50:02, Manjunathappa, Prakash wrote:
>>> From: Ajay Kumar Gupta<ajay.gupta at ti.com>

>>> On this board the OHCI port's power control and over-current signals from
>>> TPS2065 power switch are connected via GPIO2[4] and GPIO6[13] respectively,
>>> so we can implement the DA8xx OHCI glue layer's hooks for overriding the
>>> root hub port's power and over-current status bits.

>>> We also have to properly set up the clocking mode in the CFGCHIP2 register,
>>> so that internal 24 MHz reference clock is fed to the USB 2.0 (MUSB) PHY and
>>> its output is used to clock the USB 1.1 (OHCI) PHY...

>>> Signed-off-by: Ajay Kumar Gupta<ajay.gupta at ti.com>
>>> Signed-off-by: Manjunathappa, Prakash<prakash.pm at ti.com>

>> This is the third copy of OHCI platform setup code which is almost
>> the same except for the GPIO numbers.

> Well, in my counting, it's only second, DA830 EVM being the first one.
> What's the third?

    Ah, I missed Hawkboard... :-)

 >    I designed the hub interface to be as abstract as I could, and now you're
 > proposing to add GPIO to it? No, I have no clear idea how to keeep it
 > abstract and add GPIO support at the same time. I would have been grateful to
 > TI if I didn't have to invent this at all and they stop saving on OHCI pins.

    Well, I have one idea. We can create a separate module in 
arch/arm/mach-davinci/, named say ohci.c, put the shared code there and pass 
to it the GPIOs actually used via a function call. Or maybe use existing 

WBR, Sergei

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