From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sekhar Nori Subject: Re: [PATCH 4/4] ARM: dts: AM33XX: update rtc node compatibility Date: Wed, 3 Jul 2013 13:42:07 +0530 Message-ID: <51D3DCD7.2010209@ti.com> References: <1372412109-986-1-git-send-email-gururaja.hebbar@ti.com> <1372412109-986-5-git-send-email-gururaja.hebbar@ti.com> <51D26F61.7080308@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <51D26F61.7080308-l0cyMroinI0@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: Errors-To: davinci-linux-open-source-bounces-VycZQUHpC/PFrsHnngEfi1aTQe2KTcn/@public.gmane.org To: Sekhar Nori Cc: davinci-linux-open-source-VycZQUHpC/PFrsHnngEfi1aTQe2KTcn/@public.gmane.org, tony-4v6yS6AI5VpBDgjK7y7TUQ@public.gmane.org, =?UTF-8?B?QmVub8OudCBDb3Vzc29u?= , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-omap-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: devicetree@vger.kernel.org Gururaja, On 7/2/2013 11:42 AM, Sekhar Nori wrote: > Changing to Benoit's gmail id since he apparently wont access TI mail > anymore. > > On 6/28/2013 3:05 PM, Hebbar Gururaja wrote: >> Since AM33xx RTC IP has RTC_IRQWAKEEN to support Alarm Wake-up. >> >> Update the rtc compatible property to "ti,am3352-rtc" to enable handling >> of this feature inside rtc-omap driver. >> >> Signed-off-by: Hebbar Gururaja >> Cc: Tony Lindgren >> Cc: Sekhar Nori >> Cc: Kevin Hilman >> Cc: b-cousson-l0cyMroinI0@public.gmane.org >> --- >> :100644 100644 77aa1b0... dde180a... M arch/arm/boot/dts/am33xx.dtsi >> arch/arm/boot/dts/am33xx.dtsi | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/arch/arm/boot/dts/am33xx.dtsi b/arch/arm/boot/dts/am33xx.dtsi >> index 77aa1b0..dde180a 100644 >> --- a/arch/arm/boot/dts/am33xx.dtsi >> +++ b/arch/arm/boot/dts/am33xx.dtsi >> @@ -297,7 +297,7 @@ >> }; >> >> rtc@44e3e000 { >> - compatible = "ti,da830-rtc"; >> + compatible = "ti,am3352-rtc"; > > compatible is a list so you can instead do: > > compatible = "ti,am3352-rtc", "ti,da830-rtc"; > > That way the dts works irrespective of driver updates. When driver > supports enhanced features of hardware, they are available to the user > else the basic functionality still works. On doing some experiments myself, the of_device_id which gets selected during probe depends on the order in which its entry appears in the match table inside the driver rather than how the compatible string is written. I think this puts undue dependency on how the driver is written, so I am okay with providing a single compatible value like the way you have done ATM. I do think the string appearing first in the compatible list is what should be selected if a match is available but I am not sure if there are other considerations due to which of_match_device() is written the way it is written. Thanks, Sekhar