From mboxrd@z Thu Jan 1 00:00:00 1970 From: nicolas.ferre@atmel.com (Nicolas Ferre) Date: Tue, 2 Apr 2013 18:28:08 +0200 Subject: [RFC PATCH] rtc: rtc-at91rm9200: manage IMR depending on revision In-Reply-To: <515AFA0B.7020509@interlog.com> References: <1364573029-19346-5-git-send-email-jhovold@gmail.com> <1364908007-5150-1-git-send-email-nicolas.ferre@atmel.com> <515AFA0B.7020509@interlog.com> Message-ID: <515B0718.3060305@atmel.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 04/02/2013 05:32 PM, Douglas Gilbert : > On 13-04-02 09:06 AM, Nicolas Ferre wrote: >> Signed-off-by: Nicolas Ferre >> --- >> Hi all, >> >> The funny thing is that I was writing exactly the same code as Johan's >> when he posted his series. >> >> So, here is my single patch, with the comment about the readback >> stolen from >> Johan's, but without the way to determine with IP is buggy and which >> one is >> not... >> After having dug the possibility to read the IP revision, I discovered >> that it >> is not possible to use this information ("version" register offset >> changing >> according to... IP version number: well done!). >> In conclusion, I guess that the only way to determine if we need the >> workaround >> is to use the DT. >> One remark though: if we use the compatibility string for this >> purpose, I fear >> that we would twist the meaning of this information: SoC using an >> "atmel,at91sam9x5-rtc" compatible RTC will not necessarily be touched >> by the >> "non responding IMR" bug: at91sam9n12 or upcoming sama5d3 are not >> affected for >> instance, and we need to cling to "atmel,at91rm9200-rtc" for them... >> I think that we can use this method for the moment and move to another >> compatibility string later if it is needed. > > Rather than have so many people working on rtc-at91rm9200.c, > how about someone bring its "RTT" sibling into the DT > world. I'm talking about drivers/rtc/rtc-at91sam9.c ... I am currently trying to fix the issue that I have created by pushing a boggus fix to Andrew's patch series (and "stable" incidentally). So I am trying to find the best way to address this and: - a correct - a smallest possible path or patch series (I admit that I prefer a single patch). So, I am still posting rtc-at91rm9200.c patches and hoping from a feedback. Once we have a good solution I will try to include it in 3.9 and the stable trees affected. Best regards, -- Nicolas Ferre