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. Rob -- 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
