Subject: [PATCH 1/5] USB: ehci-atmel: rework clk handling

From: [email-masked] (Greg Kroah-Hartman)
Date: Wed, 18 Mar 2015 13:28:54 +0100

On Wed, Mar 18, 2015 at 12:16:22PM +0100, Nicolas Ferre wrote:
> Le 17/03/2015 20:01, Alan Stern a ?crit :
> > On Tue, 17 Mar 2015, Boris Brezillon wrote:
> > 
> >> The EHCI IP only needs the UTMI/UPLL (uclk) and the peripheral (iclk)
> >> clocks to work properly. Remove the useless system clock (fclk).
> >>
> >> Avoid calling set_rate on the fixed rate UTMI/IPLL clock and remove
> >> useless IS_ENABLED(CONFIG_COMMON_CLK) tests (all at91 platforms have been
> >> moved to the CCF).
> >>
> >> This patch also fixes a bug introduced by 3440ef1 (ARM: at91/dt: fix USB
> >> high-speed clock to select UTMI), which was leaving the usb clock
> >> uninitialized and preventing the OHCI driver from setting the usb clock
> >> rate to 48MHz.
> >> This bug was caused by several things:
> >> 1/ usb clock drivers set the CLK_SET_RATE_GATE flag, which means the rate
> >>    cannot be changed once the clock is prepared
> >> 2/ The EHCI driver was retrieving and preparing/enabling the uhpck
> >>    clock which was in turn preparing its parent clock (the usb clock),
> >>    thus preventing any rate change because of 1/
> >>
> >> Signed-off-by: Boris Brezillon <[email-masked]>
> > 
> > Acked-by: Alan Stern <[email-masked]>
> 
> Acked-by: Nicolas Ferre <[email-masked]>
> and:
> Fixes: 3440ef169100 ("ARM: at91/dt: fix USB high-speed clock to select UTMI")
> 
> Alan, Greg,
> 
> Can you please take this patch (only this patch 1/5 of the series) as a fix 
> for the 4.0-rc? It would solve the issue that we see on at91sam9x5/at91sam9n12.
> I'll take care of the rest of the series for 4.1.
> 
> If you want me to take it of to re-send the patch, tell me.

I'll queue it up now, thanks.  You can take the rest of the series :)

thanks,

greg k-h