From: Bjorn Helgaas Date: Tue, 14 Oct 2008 23:01:03 +0000 (-0600) Subject: x86: register a platform RTC device if PNP doesn't describe it X-Git-Url: http://git.kernel.org/?p=linux%2Fkernel%2Fgit%2Ftorvalds%2Flinux-2.6.git;a=commitdiff_plain;h=758a7f7bb86b520aadc484f23da85e547b3bf3d8 x86: register a platform RTC device if PNP doesn't describe it Most if not all x86 platforms have an RTC device, but sometimes the RTC is not exposed as a PNP0b00/PNP0b01/PNP0b02 device in PNPBIOS or ACPI: http://bugzilla.kernel.org/show_bug.cgi?id=11580 https://bugzilla.redhat.com/show_bug.cgi?id=451188 It's best if we can discover the RTC via PNP because then we know which flavor of device it is, where it lives, and which IRQ it uses. But if we can't, we should register a platform device using the compiled-in RTC_PORT/RTC_IRQ resource assumptions. 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 --- diff --git a/arch/x86/kernel/rtc.c b/arch/x86/kernel/rtc.c index 05191bb..0a23b57 100644 --- a/arch/x86/kernel/rtc.c +++ b/arch/x86/kernel/rtc.c @@ -223,11 +223,25 @@ static struct platform_device rtc_device = { static __init int add_rtc_cmos(void) { #ifdef CONFIG_PNP - if (!pnp_platform_devices) - platform_device_register(&rtc_device); -#else + static const char *ids[] __initconst = + { "PNP0b00", "PNP0b01", "PNP0b02", }; + struct pnp_dev *dev; + struct pnp_id *id; + int i; + + pnp_for_each_dev(dev) { + for (id = dev->id; id; id = id->next) { + for (i = 0; i < ARRAY_SIZE(ids); i++) { + if (compare_pnp_id(id, ids[i]) != 0) + return 0; + } + } + } +#endif + platform_device_register(&rtc_device); -#endif /* CONFIG_PNP */ + dev_info(&rtc_device.dev, + "registered platform RTC device (no PNP device found)\n"); return 0; } device_initcall(add_rtc_cmos); From: Bjorn Helgaas Date: Tue, 14 Oct 2008 23:01:59 +0000 (-0600) Subject: rtc-cmos: look for PNP RTC first, then for platform RTC X-Git-Url: http://git.kernel.org/?p=linux%2Fkernel%2Fgit%2Ftorvalds%2Flinux-2.6.git;a=commitdiff_plain;h=72f22b1eb6ca5e4676a632a04d40d46cb61d4562 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 --- diff --git a/drivers/rtc/rtc-cmos.c b/drivers/rtc/rtc-cmos.c index 6778f82..963ad0b 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);