From 72f22b1eb6ca5e4676a632a04d40d46cb61d4562 Mon Sep 17 00:00:00 2001 From: Bjorn Helgaas Date: Tue, 14 Oct 2008 17:01:59 -0600 Subject: [PATCH] rtc-cmos: look for PNP RTC first, then for platform RTC We shouldn't rely on "pnp_platform_devices" to tell us whether there is a PNP RTC device. I introduced "pnp_platform_devices", but I think it was a mistake. All it tells us is whether we found any PNPBIOS or PNPACPI devices. Many machines have some PNP devices, but do not describe the RTC via PNP. On those machines, we need to do the platform driver probe to find the RTC. We should just register the PNP driver and see whether it claims anything. If we don't find a PNP RTC, fall back to the platform driver probe. This (in conjunction with the arch/x86/kernel/rtc.c patch to add a platform RTC device when PNP doesn't have one) should resolve these issues: http://bugzilla.kernel.org/show_bug.cgi?id=11580 https://bugzilla.redhat.com/show_bug.cgi?id=451188 Signed-off-by: Bjorn Helgaas Acked-by: Rafael J. Wysocki Acked-by: David Brownell Reported-by: Rik Theys Reported-by: shr_msn@yahoo.com.tw Signed-off-by: Linus Torvalds --- drivers/rtc/rtc-cmos.c | 33 ++++++++++++++++++--------------- 1 file changed, 18 insertions(+), 15 deletions(-) diff --git a/drivers/rtc/rtc-cmos.c b/drivers/rtc/rtc-cmos.c index 6778f82bad24..963ad0b6a4e9 100644 --- a/drivers/rtc/rtc-cmos.c +++ b/drivers/rtc/rtc-cmos.c @@ -1120,29 +1120,32 @@ static struct platform_driver cmos_platform_driver = { static int __init cmos_init(void) { + int retval = 0; + #ifdef CONFIG_PNP - if (pnp_platform_devices) - return pnp_register_driver(&cmos_pnp_driver); - else - return platform_driver_probe(&cmos_platform_driver, - cmos_platform_probe); -#else - return platform_driver_probe(&cmos_platform_driver, - cmos_platform_probe); -#endif /* CONFIG_PNP */ + pnp_register_driver(&cmos_pnp_driver); +#endif + + if (!cmos_rtc.dev) + retval = platform_driver_probe(&cmos_platform_driver, + cmos_platform_probe); + + if (retval == 0) + return 0; + +#ifdef CONFIG_PNP + pnp_unregister_driver(&cmos_pnp_driver); +#endif + return retval; } module_init(cmos_init); static void __exit cmos_exit(void) { #ifdef CONFIG_PNP - if (pnp_platform_devices) - pnp_unregister_driver(&cmos_pnp_driver); - else - platform_driver_unregister(&cmos_platform_driver); -#else + pnp_unregister_driver(&cmos_pnp_driver); +#endif platform_driver_unregister(&cmos_platform_driver); -#endif /* CONFIG_PNP */ } module_exit(cmos_exit); -- 2.20.1