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2013-04-05Revert "drivers/rtc/rtc-at91rm9200.c: use a variable for storing IMR"Johan Hovold1-0/+1
This reverts commit 0ef1594c017521ea89278e80fe3f80dafb17abde. This patch introduced a few races which cannot be easily fixed with a small follow-up patch. Furthermore, the SoC with the broken hardware register, which this patch intended to add support for, can only be used with device trees, which this driver currently does not support. [ Here is the discussion that led to this "revert" patch: https://lkml.org/lkml/2013/4/3/176 ] Cc: stable <stable@vger.kernel.org> Signed-off-by: Johan Hovold <jhovold@gmail.com> Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-03-22drivers/rtc/rtc-at91rm9200.c: use a variable for storing IMRNicolas Ferre1-1/+0
On some revisions of AT91 SoCs, the RTC IMR register is not working. Instead of elaborating a workaround for that specific SoC or IP version, we simply use a software variable to store the Interrupt Mask Register and modify it for each enabling/disabling of an interrupt. The overhead of this is negligible anyway. The interrupt mask register (IMR) for the RTC is broken on the AT91SAM9x5 sub-family of SoCs (good overview of the members here: http://www.eewiki.net/display/linuxonarm/AT91SAM9x5 ). The "user visible effect" is the RTC doesn't work. That sub-family is less than two years old and only has devicetree (DT) support and came online circa lk 3.7 . The dust is yet to settle on the DT stuff at least for AT91 SoCs (translation: lots of stuff is still broken, so much that it is hard to know where to start). The fix in the patch is pretty simple: just shadow the silicon IMR register with a variable in the driver. Some older SoCs (pre-DT) use the the rtc-at91rm9200 driver (e.g. obviously the AT91RM9200) and they should not be impacted by the change. There shouldn't be a large volume of interrupts associated with a RTC. Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com> Reported-by: Douglas Gilbert <dgilbert@interlog.com> Cc: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> Cc: Ludovic Desroches <ludovic.desroches@atmel.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-11-06arm: at91: move at91rm9200 rtc header in drivers/rtcJean-Christophe PLAGNIOL-VILLARD1-0/+75
Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> Cc: Nicolas Ferre <nicolas.ferre@atmel.com>