[PATCH] ARM: davinci: register the usb20_phy clock on the DT file

David Lechner david at lechnology.com
Wed Oct 26 13:08:21 PDT 2016


On 10/26/2016 03:05 PM, Axel Haslam wrote:
> On Wed, Oct 26, 2016 at 10:03 PM, David Lechner <david at lechnology.com> wrote:
>> On 10/26/2016 03:01 PM, David Lechner wrote:
>>>
>>> On 10/26/2016 02:49 PM, ahaslam at baylibre.com wrote:
>>>>
>>>> From: Axel Haslam <ahaslam at baylibre.com>
>>>>
>>>> The usb20_phy clock needs to be registered for the driver to be able
>>>> to get and enable a clock. Currently the usb phy clocks are registered
>>>> form board files, which will not be called during a device tree based
>>>> boot.
>>>>
>>>> To be able to probe correctly usb form a device tree boot, register
>>>> the usb phy clocks form the DT specific init.
>>>>
>>>> Unfourtunatly, davinci does not have proper clock support on device tree
>>>> yet, so by registering the clock form de DT specific file we are
>>>> forced to hardcode the parent clock, and cannot select refclkin as
>>>> parent for any of the phy clocks of the da850 family.
>>>>
>>>> As none of the current da850 based boards currently in mainline use
>>>> refclkin as source. I guess we can live with this limitation until clocks
>>>> are correctly represented through CCF/device tree.
>>>>
>>>> Signed-off-by: Axel Haslam <ahaslam at baylibre.com>
>>>> ---
>>>>
>>>> This patch depends on David's series for usb clocks:
>>>>
>>>> currently:
>>>> [PATCH v6 0/5] da8xx USB PHY platform devices and clocks
>>>> https://lkml.org/lkml/2016/10/25/867
>>>>
>>>>  arch/arm/mach-davinci/da8xx-dt.c | 2 ++
>>>>  1 file changed, 2 insertions(+)
>>>>
>>>> diff --git a/arch/arm/mach-davinci/da8xx-dt.c
>>>> b/arch/arm/mach-davinci/da8xx-dt.c
>>>> index c9f7e92..7947267 100644
>>>> --- a/arch/arm/mach-davinci/da8xx-dt.c
>>>> +++ b/arch/arm/mach-davinci/da8xx-dt.c
>>>> @@ -45,6 +45,8 @@
>>>>
>>>>  static void __init da850_init_machine(void)
>>>>  {
>>>> +    da8xx_register_usb20_phy_clk(false);
>>>> +    da8xx_register_usb11_phy_clk(false);
>>>>      of_platform_default_populate(NULL, da850_auxdata_lookup, NULL);
>>>>  }
>>>>
>>>>
>>>
>>>
>>> You should check for error on return and print a warning if there is an
>>> error. Like this: https://patchwork.kernel.org/patch/9395635/
>>>
>>> (I actually just had to make this change a few minutes ago to
>>> troubleshoot a problem that I am working on.
>>> da8xx_register_usb11_phy_clk() is failing for some reason that I have
>>> not figured out yet.)
>>
>>
>>
>> And actually, since my patch that provides these functions has not been
>> accepted yet, why don't I just add this change to that series?
>
> Ok, sure, if you are planing on sending another version.
>
> Regards
> Axel
>

Yes, I have some more changes to make and resubmit, so I will include 
this too.



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