On 19 January 2016 at 19:20, Rob Herring <robh+dt@xxxxxxxxxx> wrote: > On Fri, Jan 15, 2016 at 1:57 AM, xuejiancheng <xuejiancheng@xxxxxxxxxx> wrote: >> >> On 2016/1/14 21:16, xuejiancheng wrote: >>> Hi Mike, >>> >>> On 2016/1/14 2:57, Michael Turquette wrote: >>>> Quoting xuejiancheng (2016-01-12 19:03:01) >>>>> Hi Stephen, >>>>> Thank you very much for your reply. >>>>> >>>>> On 2016/1/13 6:12, Stephen Boyd wrote: >>>>>> On 01/08, Jiancheng Xue wrote: >>>>>>> diff --git a/drivers/clk/hisilicon/Kconfig b/drivers/clk/hisilicon/Kconfig >>>>>>> index e434854..b6baebf 100644 >>>>>>> --- a/drivers/clk/hisilicon/Kconfig >>>>>>> +++ b/drivers/clk/hisilicon/Kconfig >>>>>>> @@ -1,3 +1,10 @@ >>>>>>> +config COMMON_CLK_HI3519 >>>>>>> + tristate "Clock Driver for Hi3519" >>>>>> >>>>>> It looks like this has to be bool. Otherwise it needs to be a >>>>>> platform driver and the hisilicon APIs need to be exported and >>>>>> lose their __init markings. >>>>>> >>>>> Yes,it's a problem. I will fix it in next version. Thank you. >>>> >>>> The best solution would be to make this clock driver a real platform >>>> driver. >>>> >>> Now the work clock of the clocksource timer-sp804 is provided by this driver. So >>> it need to be registered early by CLK_OF_DECLARE. If the timer clock is treated >>> as a fixed-clock provider, this driver can be implemented as a platform driver. >>> Then the crg device must be registered before other clock consumer devices.Accordingly >>> the crg device node must be written above all other clock consumer devices node in dts files. >>> I think it is also a dependence. >>> >>> Can you help me understand why it is better to make this driver a platform driver? >>> Thank you very much! >>> >> arch_initcall(customize_machine) >> -->of_platform_populate >> -->of_platform_bus_create >> -->of_amba_device_create >> -->amba_device_add >> -->amba_get_enable_pclk >> The call sequence above shows that the clock of the amba device must be registered before >> amba_device_add. The clock of "arm,pl011" uart is registered in the probe function of the >> platform driver "hi3519-crg". So the platform device "hi3519-crg" must be created before >> the amba device "arm,pl011" uart. > > It is a problem, but Tomeu had a fix to support deferred probes here. > That was part of the on-demand probing series, but maybe it needs to > be applied separately if we are moving clock drivers to platform > drivers. Hi, Marek Szyprowski has kindly taken those two patches as part of a series of him: http://lkml.kernel.org/g/1450868368-5650-1-git-send-email-m.szyprowski@xxxxxxxxxxx I think it would be great if you could test them and report. Thanks, Tomeu -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
