On 18.12.2019 18:58, Alexandre Belloni wrote: > On 18/12/2019 16:52:21+0000, Eugen.Hristev@xxxxxxxxxxxxx wrote: >> >> >> On 18.12.2019 18:43, Alexandre Belloni wrote: >> >>> Hi, >>> >>> On 18/12/2019 16:24:00+0000, Eugen.Hristev@xxxxxxxxxxxxx wrote: >>>> From: Eugen Hristev <eugen.hristev@xxxxxxxxxxxxx> >>>> >>>> This allows the RTC node to have child nodes in DT. >>>> This allows subnodes to be probed. >>>> >>>> Signed-off-by: Eugen Hristev <eugen.hristev@xxxxxxxxxxxxx> >>>> --- >>>> drivers/rtc/rtc-at91rm9200.c | 2 +- >>>> 1 file changed, 1 insertion(+), 1 deletion(-) >>>> >>>> diff --git a/drivers/rtc/rtc-at91rm9200.c b/drivers/rtc/rtc-at91rm9200.c >>>> index 3b833e0..f1b5b3d 100644 >>>> --- a/drivers/rtc/rtc-at91rm9200.c >>>> +++ b/drivers/rtc/rtc-at91rm9200.c >>>> @@ -421,7 +421,7 @@ static int __init at91_rtc_probe(struct platform_device *pdev) >>>> at91_rtc_write_ier(AT91_RTC_SECEV); >>>> >>>> dev_info(&pdev->dev, "AT91 Real Time Clock driver.\n"); >>>> - return 0; >>>> + return of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev); >>>> >>> >>> You can avoid the DT binding change and DT parsing by using >>> platform_add_device here. I don't think there is any point describing >>> the trigger as a child node (a watchdog functionality wouldn't be >>> described for example). >>> >> >> Hi, >> >> It's needed because the ADC needs a link to the trigger device. This is >> a hardware link inside the SoC, so I thought the best way is to describe >> this hardware is in the Device Tree. >> Otherwise the ADC node is unaware of the RTC triggering possibility. >> If we just assign the RTC trigger device to the ADC through the sysfs, >> the ADC cannot distinguish between the RTC trigger and other various >> triggers which can be attached. >> > > I'm not sure this links is required but I will let Jonathan review. Even > if it is needed, you can still use the rtc node to describe that link. Actually, the RTC node could potentially have two different ADC triggers. There is another OUT1 field that can do a second trigger for the ADC only for the last channel. Future development might add this trigger, so, with that in mind, I think it's best to link the exact trigger and not the RTC node. > > -- > Alexandre Belloni, Bootlin > Embedded Linux and Kernel engineering > https://bootlin.com >
