[PATCH 0/2 v2] S3C64XX: Fix 48M clock enable

Paulius Zaleckas paulius.zaleckas at gmail.com
Tue Oct 12 09:49:05 EDT 2010


On Tue, Oct 12, 2010 at 3:55 PM, Marek Szyprowski
<m.szyprowski at samsung.com> wrote:
> Hello,
>
> On Tuesday, October 12, 2010 2:41 PM Paulius Zaleckas wrote:
>
>> To enable 48M clock USB PHY must be initialized since 48M
>> is output of USB PHY PLL.
>> So fix a problem where other devices requiring 48M clock will
>> not work unless USB OTG driver is enabled.
>> is_osc was removed from OTG drivers platform data and implemented
>> as separate function s3c6400_clk_xusbxti_is_osc which should be
>> called from machine_init. Currently there is no in-kernel users
>> of it.
>>
>> This fix is only for S3C64xx family, but I am sure something
>> similar will be needed for S5P family. I have started the work
>> but I am unable to finnish it since I only have datasheet for
>> S5PC100. Maybe Samsung guys could help me with this..?
>> However current patches doesn't break S5P since it is not
>> using s3c-hsotg driver (yet?).
>
> There are patches that enables the driver on S5PC110/S5PV210 series
> on kgene/for-next tree. Please note that at least Samsung Goni and
> Samsung Aquila uses external oscillator to supply usb clock. Please
> refer to:
>
> http://git.kernel.org/?p=linux/kernel/git/kgene/linux-samsung.git;a=commit;h=e5e044e637228be8bdf033c0772f9e5926269ae0

Interesting patch... If Goni uses oscillator then it will fail with current
otg driver since it will configure phy for crystal, because is_otg is not set
in the platform data.

> http://git.kernel.org/?p=linux/kernel/git/kgene/linux-samsung.git;a=commit;h=a33bc34103b4fc4eca13cdd61f2579857797bbf7

This patch contains some really nasty workaround for S3C64XX_OTHERS
Mine version allows to get rid of it.

I have some preliminary version of patch for s5p. I will send it to you in
the evening.



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