From: Laurence de Bruxelles lfdebrux@gmail.com
commit 34127b3632b21e5c391756e724b1198eb9917981 upstream.
With the latest stable kernel versions the rtc on the PXA based Zaurus does not work, when booting I see the following kernel messages:
pxa-rtc pxa-rtc: failed to find rtc clock source pxa-rtc pxa-rtc: Unable to init SA1100 RTC sub-device pxa-rtc: probe of pxa-rtc failed with error -2 hctosys: unable to open rtc device (rtc0)
I think this is because commit f2997775b111 ("rtc: sa1100: fix possible race condition") moved the allocation of the rtc_device struct out of sa1100_rtc_init and into sa1100_rtc_probe. This means that pxa_rtc_probe also needs to do allocation for the rtc_device struct, otherwise sa1100_rtc_init will try to dereference a null pointer. This patch adds that allocation by copying how sa1100_rtc_probe in drivers/rtc/rtc-sa1100.c does it; after the IRQs are set up a managed rtc_device is allocated.
I've tested this patch with `qemu-system-arm -machine akita` and with a real Zaurus SL-C1000 applied to 4.19, 5.4, and 5.10.
Signed-off-by: Laurence de Bruxelles lfdebrux@gmail.com Fixes: f2997775b111 ("rtc: sa1100: fix possible race condition") Signed-off-by: Alexandre Belloni alexandre.belloni@bootlin.com Link: https://lore.kernel.org/r/20220101154149.12026-1-lfdebrux@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/rtc/rtc-pxa.c | 4 ++++ 1 file changed, 4 insertions(+)
--- a/drivers/rtc/rtc-pxa.c +++ b/drivers/rtc/rtc-pxa.c @@ -349,6 +349,10 @@ static int __init pxa_rtc_probe(struct p return -ENXIO; }
+ sa1100_rtc->rtc = devm_rtc_allocate_device(&pdev->dev); + if (IS_ERR(sa1100_rtc->rtc)) + return PTR_ERR(sa1100_rtc->rtc); + pxa_rtc->base = devm_ioremap(dev, pxa_rtc->ress->start, resource_size(pxa_rtc->ress)); if (!pxa_rtc->base) {