Re: [PATCH] arm: omap4: pandaboard: turn on PHY reference clock at init

From: Ming Lei
Date: Mon Jan 10 2011 - 10:45:24 EST


Hi,

2011/1/10 Anand Gadiyar <gadiyar@xxxxxx>:
> The SMSC 3320 USB PHY on the OMAP4 Pandaboard needs a 19.2 MHz
> reference clock. This clock is provided from the OMAP4's fref_clk3
> pad.
>
> Recent changes to clock44xx_data.c made the clock framework aware
> of the existence of these fref_clk[i] lines. If the option
> CONFIG_OMAP_RESET_CLOCKS is enabled in the kernel, then the
> clock framework will turn these clocks off during bootup.
>
> Explicitly request and keep this clock enabled at init for the
> Pandaboard, so that the PHY receives this clock at all times.
>
> Reported-by: Ming Lei <tom.leiming@xxxxxxxxx>
> Signed-off-by: Anand Gadiyar <gadiyar@xxxxxx>
> Cc: Benoit Cousson <b-cousson@xxxxxx>
> Cc: Paul Walmsley <paul@xxxxxxxxx>
> Cc: Tony Lindgren <tony@xxxxxxxxxxx>
> ---
> Tony,
>
> The clock database changes were merged just before Christmas, so
> we did not detect this sooner. Would be nice to get this merged in
> the -rc series, so that we get EHCI and ethernet functional on the Panda.
>
> Ming Lei,
>
> Could you please test this and confirm it fixes the issue for you?

Yes, the patch does fix the issue on my panda board even
CONFIG_OMAP_RESET_CLOCKS is enabled.

thanks,
--
Lei Ming
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