Messages in this thread | | | Subject | Re: [PATCH 0/5] da8xx USB clocks | From | Sergei Shtylyov <> | Date | Wed, 16 Mar 2016 15:36:54 +0300 |
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On 3/16/2016 1:35 AM, David Lechner wrote:
> I've implemented some proper clocks for the USB PHY clocks on da8xx. For those > not familiar with the architecture, the SoC has one USB 1.1 OHCI port and one > USB 2.O OTG port. The USB 1.1 PHY clock can optionally be supplied by the PLL > in the USB 2.0 PHY. > > I have seen some comments in the past that these clock details don't belong in > the USB drivers and I agree with that. So, I have moved the handling of the > clocks out of the USB drivers to the mach code with the rest of the SoC clocks. > > This code has been tested on LEGO MINDSTORMS EV3 (AM1808/da850 family). Here is > an output of the davinci clock debug to give you a better idea of how clocks > are related. > > root@ev3dev:~# cat /sys/kernel/debug/davinci_clocks > ref_clk users=23 24000000 Hz > pll0 users=20 pll 300000000 Hz > pll0_aux_clk users= 4 pll 24000000 Hz > ... > usb20_phy users= 2 24000000 Hz > usb11_phy users= 1 24000000 Hz > ... > usb_ref_clk users= 0 48000000 Hz > > usb20_phy and usb11_phy can optionally be children of usb_ref_clk instead. > > > I'm planning on adding device tree bindings for the ohci driver, but I need to > get some things sorted out with the regulator subsystem first. I see that Petr > has been working on device tree support for the musb driver. This should take > care of some of the concerns related to his changes too, for example, the > ti,usb2-phy-refclock-hz device tree property is no longer needed because it > is now taken care of in the clock code. I've actually included one of Petr's > patchs here since one of my patches depends on it. > > I'm also working on device tree bindings for davinci clocks, but it will take > me a while to get there. But that should not hold up the device tree bindings > for da8xx ohci and musb.
Nice to see that someone still cares about this code. With the ending of the MontaVista's efforts, it largely seemed like abandonware...
MBR, Sergei
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