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path: root/drivers/rtc/rtc-cmos.c
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2020-12-20Merge tag 'rtc-5.11' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux Pull RTC updates from Alexandre Belloni: "Subsystem: - Remove nvram ABI. There was no complaints about the deprecation for the last 3 years. - Improve RTC device allocation and registration - Now available for ARCH=um Drivers: - at91rm9200: correction and sam9x60 support - ds1307: improve ACPI support - mxc: now DT only - pcf2127: watchdog support now needs the reset-source property - pcf8523: set range - rx6110: i2c support" * tag 'rtc-5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (43 commits) rtc: pcf2127: only use watchdog when explicitly available dt-bindings: rtc: add reset-source property rtc: fix RTC removal rtc: s3c: Remove dead code related to periodic tick handling rtc: s3c: Disable all enable (RTC, tick) bits in the probe rtc: ep93xx: Fix NULL pointer dereference in ep93xx_rtc_read_time rtc: test: remove debug message rtc: mxc{,_v2}: enable COMPILE_TEST rtc: enable RTC framework on ARCH=um rtc: pcf8523: use BIT rtc: pcf8523: set range rtc: pcf8523: switch to devm_rtc_allocate_device rtc: destroy mutex when releasing the device rtc: shrink devm_rtc_allocate_device() rtc: rework rtc_register_device() resource management rtc: nvmem: emit an error message when nvmem registration fails rtc: add devm_ prefix to rtc_nvmem_register() rtc: nvmem: remove nvram ABI Documentation: list RTC devres helpers in devres.rst rtc: omap: use devm_pinctrl_register() ...
2020-12-11ntp: Make the RTC sync offset less obscureThomas Gleixner
The current RTC set_offset_nsec value is not really intuitive to understand. tsched twrite(t2.tv_sec - 1) t2 (seconds increment) The offset is calculated from twrite based on the assumption that t2 - twrite == 1s. That means for the MC146818 RTC the offset needs to be negative so that the write happens 500ms before t2. It's easier to understand when the whole calculation is based on t2. That avoids negative offsets and the meaning is obvious: t2 - twrite: The time defined by the chip when seconds increment after the write. twrite - tsched: The time for the transport to the point where the chip is updated. ==> set_offset_nsec = t2 - tsched ttransport = twrite - tsched tRTCinc = t2 - twrite ==> set_offset_nsec = ttransport + tRTCinc tRTCinc is a chip property and can be obtained from the data sheet. ttransport depends on how the RTC is connected. It is close to 0 for directly accessible RTCs. For RTCs behind a slow bus, e.g. i2c, it's the time required to send the update over the bus. This can be estimated or even calibrated, but that's a different problem. Adjust the implementation and update comments accordingly. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Link: https://lore.kernel.org/r/20201206220542.263204937@linutronix.de
2020-12-11rtc: cmos: Make rtc_cmos sync offset correctThomas Gleixner
The offset for rtc_cmos must be -500ms to work correctly with the current implementation of rtc_set_ntp_time() due to the following: tsched twrite(t2.tv_sec - 1) t2 (seconds increment) twrite - tsched is the transport time for the write to hit the device, which is negligible for this chip because it's accessed directly. t2 - twrite = 500ms according to the datasheet. But rtc_set_ntp_time() calculation of tsched is: tsched = t2 - 1sec - (t2 - twrite) The default for the sync offset is 500ms which means that the write happens at t2 - 1.5 seconds which is obviously off by a second for this device. Make the offset -500ms so it works correct. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Link: https://lore.kernel.org/r/20201206220541.830517160@linutronix.de
2020-11-19rtc: rework rtc_register_device() resource managementBartosz Golaszewski
rtc_register_device() is a managed interface but it doesn't use devres by itself - instead it marks an rtc_device as "registered" and the devres callback for devm_rtc_allocate_device() takes care of resource release. This doesn't correspond with the design behind devres where managed structures should not be aware of being managed. The correct solution here is to register a separate devres callback for unregistering the device. While at it: rename rtc_register_device() to devm_rtc_register_device() and add it to the list of managed interfaces in devres.rst. This way we can avoid any potential confusion of driver developers who may expect there to exist a corresponding unregister function. Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Link: https://lore.kernel.org/r/20201109163409.24301-8-brgl@bgdev.pl
2020-11-19rtc: nvmem: emit an error message when nvmem registration failsBartosz Golaszewski
Some users check the return value of devm_rtc_nvmem_register() only in order to emit an error message and then continue probing. This is fine as an rtc can function without exposing nvmem but let's generalize it: let's make the registration function emit the error message so that users don't have to. Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Link: https://lore.kernel.org/r/20201109163409.24301-7-brgl@bgdev.pl
2020-11-19rtc: add devm_ prefix to rtc_nvmem_register()Bartosz Golaszewski
rtc_nvmem_register() is a managed interface. It doesn't require any release function to be called at driver detach. To avoid confusing driver authors, let's rename it to devm_rtc_nvmem_register() and add it to the list of managed interfaces in Documentation/. Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Link: https://lore.kernel.org/r/20201109163409.24301-6-brgl@bgdev.pl
2020-11-19rtc: nvmem: remove nvram ABIAlexandre Belloni
The nvram sysfs attributes have been deprecated at least since v4.13, more than 3 years ago and nobody ever complained about the deprecation warning. Remove the sysfs attributes now. [Bartosz: remove the declaration of rtc_nvmem_unregister()] Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> Link: https://lore.kernel.org/r/20201109163409.24301-5-brgl@bgdev.pl
2020-08-21rtc: cmos: zero-init wkalrm when reading from CMOSVictor Ding
cmos_read_alarm() may leave certain fields of a struct rtc_wkalrm untouched; therefore, these fields contain garbage if not properly initialized, leading to inconsistent values when converting into time64_t. This patch to zero initialize the struct before calling cmos_read_alarm(). Note that this patch is not intended to produce a correct time64_t, it is only to produce a consistent value. In the case of suspend/resume, a correct time64_t is not necessary; a consistent value is sufficient to correctly perform an equality test for t_current_expires and t_saved_expires. Logic to deduce a correct time64_t is expensive and hence should be avoided. Signed-off-by: Victor Ding <victording@google.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Link: https://lore.kernel.org/r/20200814191654.v2.1.Iaf7638a2f2a87ff68d85fcb8dec615e41340c97f@changeid
2020-04-04Merge tag 'rtc-5.7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux Pull RTC updates from Alexandre Belloni: "More cleanup this cycle, with the final goal of removing the rtc_time_to_tm and rtc_tm_to_time wrappers. All the drivers that have been modified for this now are ready for the end of times (whether it happens in 2033, 2038, 2106, 2127 or even 4052). There is also a single new driver and the usual fixes and features. Summary: Subsystem: - The rtc_time_to_tm and rtc_tm_to_time wrappers have finally been removed and only the 64bit version remain. - hctosys now works with drivers compiled as modules New driver: - MediaTek MT2712 SoC based RTC Drivers: - set range for 88pm860x, au1xxx, cpcap, da9052, davinci, ds1305, ds1374, mcp5121, pl030, pl031, pm8xxx, puv3, sa1100, sirfsoc, starfire, sun6i - ds1307: DS1388 oscillator failure detection and watchdog support - jz4740: JZ4760 support - pcf85063: clock out pin support - sun6i: external 32k oscillator is now optional, the range is now handled by the core, providing a solution for 2034" * tag 'rtc-5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (87 commits) rtc: ds1307: check for failed memory allocation on wdt rtc: class: remove redundant assignment to variable err rtc: remove rtc_time_to_tm and rtc_tm_to_time rtc: sun6i: let the core handle rtc range rtc: sun6i: switch to rtc_time64_to_tm/rtc_tm_to_time64 rtc: ds1307: add support for watchdog timer on ds1388 rtc: da9052: switch to rtc_time64_to_tm/rtc_tm_to_time64 rtc: da9052: set range rtc: da9052: convert to devm_rtc_allocate_device rtc: imx-sc: Align imx sc msg structs to 4 rtc: fsl-ftm-alarm: report alarm to core rtc: pcf85063: Add pcf85063 clkout control to common clock framework rtc: make definitions in include/uapi/linux/rtc.h actually useful for user space rtc: class: avoid unnecessary lookup in hctosys dt-bindings: rtc: Convert and update jz4740-rtc doc to YAML rtc: jz4740: Rename vendor-specific DT properties rtc: jz4740: Add support for JZ4760 SoC rtc: class: support hctosys from modular RTC drivers rtc: pm8xxx: clear alarm register when alarm is not enabled rtc: omap: drop unused dt-bindings header ...
2020-03-17rtc: cmos: remove useless cast for driver_nameCorentin Labbe
Now the pnp_driver name is "const char *", there are no need to cast driver_name. Signed-off-by: Corentin Labbe <clabbe@baylibre.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-03-03rtc: cmos: Use spin_lock_irqsave() in cmos_interrupt()Ville Syrjälä
cmos_interrupt() isn't always called from hardirq context, so we must use spin_lock_irqsave() & co. ================================ WARNING: inconsistent lock state 5.6.0-rc2-CI-CI_DRM_7981+ #1 Tainted: G U -------------------------------- inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage. rtcwake/4315 [HC0[0]:SC0[0]:HE1:SE1] takes: ffffffff82635198 (rtc_lock){?...}, at: cmos_interrupt+0x18/0x100 {IN-HARDIRQ-W} state was registered at: lock_acquire+0xa7/0x1c0 _raw_spin_lock+0x2a/0x40 cmos_interrupt+0x18/0x100 rtc_handler+0x75/0xc0 acpi_ev_fixed_event_detect+0xf9/0x132 acpi_ev_sci_xrupt_handler+0xb/0x28 acpi_irq+0x13/0x30 __handle_irq_event_percpu+0x41/0x2c0 handle_irq_event_percpu+0x2b/0x70 handle_irq_event+0x2f/0x50 handle_fasteoi_irq+0x8e/0x150 do_IRQ+0x7e/0x160 ret_from_intr+0x0/0x35 mwait_idle+0x7e/0x200 do_idle+0x1bb/0x260 cpu_startup_entry+0x14/0x20 start_secondary+0x15f/0x1b0 secondary_startup_64+0xa4/0xb0 irq event stamp: 42003 hardirqs last enabled at (42003): [<ffffffff81a36567>] _raw_spin_unlock_irqrestore+0x47/0x60 hardirqs last disabled at (42002): [<ffffffff81a362ed>] _raw_spin_lock_irqsave+0xd/0x50 softirqs last enabled at (41848): [<ffffffff81e00385>] __do_softirq+0x385/0x47f softirqs last disabled at (41841): [<ffffffff810bab3a>] irq_exit+0xba/0xc0 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(rtc_lock); <Interrupt> lock(rtc_lock); *** DEADLOCK *** 6 locks held by rtcwake/4315: #0: ffff888175dc9408 (sb_writers#5){.+.+}, at: vfs_write+0x1a4/0x1d0 #1: ffff88817406ca80 (&of->mutex){+.+.}, at: kernfs_fop_write+0xdd/0x1b0 #2: ffff888179be85e0 (kn->count#236){.+.+}, at: kernfs_fop_write+0xe6/0x1b0 #3: ffffffff82641e00 (system_transition_mutex){+.+.}, at: pm_suspend+0xb3/0x3b0 #4: ffffffff826b3ee0 (acpi_scan_lock){+.+.}, at: acpi_suspend_begin+0x47/0x80 #5: ffff888178fc3960 (&dev->mutex){....}, at: device_resume+0x92/0x1c0 stack backtrace: CPU: 3 PID: 4315 Comm: rtcwake Tainted: G U 5.6.0-rc2-CI-CI_DRM_7981+ #1 Hardware name: Google Soraka/Soraka, BIOS MrChromebox-4.10 08/25/2019 Call Trace: dump_stack+0x71/0x9b mark_lock+0x49a/0x500 ? print_shortest_lock_dependencies+0x200/0x200 __lock_acquire+0x6d4/0x15d0 ? __lock_acquire+0x460/0x15d0 lock_acquire+0xa7/0x1c0 ? cmos_interrupt+0x18/0x100 _raw_spin_lock+0x2a/0x40 ? cmos_interrupt+0x18/0x100 cmos_interrupt+0x18/0x100 cmos_resume+0x1fd/0x290 ? __acpi_pm_set_device_wakeup+0x24/0x100 pnp_bus_resume+0x5e/0x90 ? pnp_bus_suspend+0x10/0x10 dpm_run_callback+0x64/0x280 device_resume+0xd4/0x1c0 ? dpm_watchdog_set+0x60/0x60 dpm_resume+0x106/0x410 ? dpm_resume_early+0x38c/0x3e0 dpm_resume_end+0x8/0x10 suspend_devices_and_enter+0x16f/0xbe0 ? rcu_read_lock_sched_held+0x4d/0x80 pm_suspend+0x344/0x3b0 state_store+0x78/0xe0 kernfs_fop_write+0x112/0x1b0 vfs_write+0xb9/0x1d0 ksys_write+0x9f/0xe0 do_syscall_64+0x4f/0x220 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7ff934307154 Code: 89 02 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 8d 05 b1 07 2e 00 8b 00 85 c0 75 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 f3 c3 66 90 41 54 55 49 89 d4 53 48 89 f5 RSP: 002b:00007ffe2647c168 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007ff934307154 RDX: 0000000000000004 RSI: 000055de3ec4e5a0 RDI: 000000000000000a RBP: 000055de3ec4e5a0 R08: 000055de3ec4c5e0 R09: 00007ff9349f3740 R10: 000055de3ec4a010 R11: 0000000000000246 R12: 000055de3ec4c500 R13: 0000000000000004 R14: 00007ff9345df2a0 R15: 00007ff9345de760 Fixes: c6d3a278cc12 ("rtc: cmos: acknowledge ACPI driven wake alarms upon resume") Fixes: 311ee9c151ad ("rtc: cmos: allow using ACPI for RTC alarm instead of HPET") Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://lore.kernel.org/r/20200221144739.11746-1-ville.syrjala@linux.intel.com Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2020-01-25rtc: cmos: Refactor code by using the new dmi_get_bios_year() helperAndy Shevchenko
Refactor code by using the new dmi_get_bios_year() helper instead of open coding its functionality. This also makes logic slightly clearer. No changes intended. Cc: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Tested-by: Guilherme G. Piccoli <gpiccoli@canonical.com> Reviewed-by: Hans de Goede <hdegoede@redhat.com> Link: https://lore.kernel.org/r/20200123131437.28157-3-andriy.shevchenko@linux.intel.com Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2020-01-25rtc: cmos: Use predefined value for RTC IRQ on legacy x86Andy Shevchenko
When legacy devices are present on x86 machine, the RTC IRQ has a dedicated pre-defined value. Use it instead of hard coded number. Cc: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Tested-by: Guilherme G. Piccoli <gpiccoli@canonical.com> Reviewed-by: Hans de Goede <hdegoede@redhat.com> Link: https://lore.kernel.org/r/20200123131437.28157-2-andriy.shevchenko@linux.intel.com Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2020-01-25rtc: cmos: Stop using shared IRQAndy Shevchenko
As reported by Guilherme G. Piccoli: ---8<---8<---8<--- The rtc-cmos interrupt setting was changed in the commit 079062b28fb4 ("rtc: cmos: prevent kernel warning on IRQ flags mismatch") in order to allow shared interrupts; according to that commit's description, some machine got kernel warnings due to the interrupt line being shared between rtc-cmos and other hardware, and rtc-cmos didn't allow IRQ sharing that time. After the aforementioned commit though it was observed a huge increase in lost HPET interrupts in some systems, observed through the following kernel message: [...] hpet1: lost 35 rtc interrupts After investigation, it was narrowed down to the shared interrupts usage when having the kernel option "irqpoll" enabled. In this case, all IRQ handlers are called for non-timer interrupts, if such handlers are setup in shared IRQ lines. The rtc-cmos IRQ handler could be set to hpet_rtc_interrupt(), which will produce the kernel "lost interrupts" message after doing work - lots of readl/writel to HPET registers, which are known to be slow. Although "irqpoll" is not a default kernel option, it's used in some contexts, one being the kdump kernel (which is an already "impaired" kernel usually running with 1 CPU available), so the performance burden could be considerable. Also, the same issue would happen (in a shorter extent though) when using "irqfixup" kernel option. In a quick experiment, a virtual machine with uptime of 2 minutes produced >300 calls to hpet_rtc_interrupt() when "irqpoll" was set, whereas without sharing interrupts this number reduced to 1 interrupt. Machines with more hardware than a VM should generate even more unnecessary HPET interrupts in this scenario. ---8<---8<---8<--- After looking into the rtc-cmos driver history and DSDT table from the Microsoft Surface 3, we may notice that Hans de Goede submitted a correct fix (see dependency below). Thus, we simply revert the culprit commit. Fixes: 079062b28fb4 ("rtc: cmos: prevent kernel warning on IRQ flags mismatch") Depends-on: a1e23a42f1bd ("rtc: cmos: Do not assume irq 8 for rtc when there are no legacy irqs") Reported-by: Guilherme G. Piccoli <gpiccoli@canonical.com> Cc: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Tested-by: Guilherme G. Piccoli <gpiccoli@canonical.com> Reviewed-by: Hans de Goede <hdegoede@redhat.com> Link: https://lore.kernel.org/r/20200123131437.28157-1-andriy.shevchenko@linux.intel.com Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-07rtc: cmos: Do not export alarm rtc_ops when we do not support alarmsHans de Goede
When there is no IRQ configured for the RTC, the rtc-cmos code does not support alarms, all alarm rtc_ops fail with -EIO / -EINVAL. The rtc-core expects a rtc driver which does not support rtc alarms to not have alarm ops at all. Otherwise the wakealarm sysfs attr will read as empty rather then returning an error, making it impossible for userspace to find out beforehand if alarms are supported. A system without an IRQ for the RTC before this patch: [root@localhost ~]# cat /sys/class/rtc/rtc0/wakealarm [root@localhost ~]# After this patch: [root@localhost ~]# cat /sys/class/rtc/rtc0/wakealarm cat: /sys/class/rtc/rtc0/wakealarm: No such file or directory [root@localhost ~]# This fixes gnome-session + systemd trying to use suspend-then-hibernate, which causes systemd to abort the suspend when writing the RTC alarm fails. BugLink: https://github.com/systemd/systemd/issues/9988 Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-10-04rtc: cmos: Remove the `use_acpi_alarm' module parameter for !ACPIMaciej W. Rozycki
Fix a problem with commit 311ee9c151ad ("rtc: cmos: allow using ACPI for RTC alarm instead of HPET") defining `use_acpi_alarm' module parameter even for non-ACPI platforms, which ignore it. Wrap the definition into #ifdef CONFIG_ACPI and use a static inline wrapper function, hardcoded to return 0 and consequently optimized away for !ACPI, following the existing pattern with HPET handling functions. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Fixes: 311ee9c151ad ("rtc: cmos: allow using ACPI for RTC alarm instead of HPET") Cc: stable@vger.kernel.org # 4.18+ Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-10-04rtc: cmos: Fix non-ACPI undefined reference to `hpet_rtc_interrupt'Maciej W. Rozycki
Fix a commit 311ee9c151ad ("rtc: cmos: allow using ACPI for RTC alarm instead of HPET") `rtc-cmos' regression causing a link error: drivers/rtc/rtc-cmos.o: In function `cmos_platform_probe': rtc-cmos.c:(.init.text+0x33c): undefined reference to `hpet_rtc_interrupt' rtc-cmos.c:(.init.text+0x3f4): undefined reference to `hpet_rtc_interrupt' with non-ACPI platforms using this driver. The cause is the change of the condition guarding the use of `hpet_rtc_interrupt'. Previously it was a call to `is_hpet_enabled'. That function is static inline and has a hardcoded 0 result for non-ACPI platforms, which imply !HPET_EMULATE_RTC. Consequently the compiler optimized the whole block away including the reference to `hpet_rtc_interrupt', which never made it to the link stage. Now the guarding condition is a call to `use_hpet_alarm', which is not static inline and therefore the compiler may not be able to prove that it actually always returns 0 for non-ACPI platforms. Consequently the build breaks with an unsatisfied reference, because `hpet_rtc_interrupt' is nowhere defined at link time. Fix the problem by marking `use_hpet_alarm' inline. As the `inline' keyword serves as an optimization hint rather than a requirement the compiler is still free to choose whether inlining will be beneficial or not for ACPI platforms. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Fixes: 311ee9c151ad ("rtc: cmos: allow using ACPI for RTC alarm instead of HPET") Cc: stable@vger.kernel.org # 4.18+ Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-04-19rtc: cmos: introduce quirks to enable use_acpi_alarm modeZhang Rui
Use ACPI for RTC Alarm only for Intel platforms 1. with Low Power S0 support 2. with HPET RTC emulation enabled 3. no earlier than 2015 Note that, during the test, it is found that this patch 1. works in 4.15-rc kernel 2. hangs the platform after suspend-to-idle for 2 or 3 times, in 4.15.0 3. works again in 4.16-rc3 kernel. 4. works in the latest 4.15.12 stable kernel. Thus although this patch breaks 4.15.0 kernel for some unknown reason, still, it is safe for both upstream and backport. Signed-off-by: Zhang Rui <rui.zhang@intel.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-04-19rtc: cmos: acknowledge ACPI driven wake alarms upon resumeZhang Rui
Previously, the RTC alarm is acknowledged either by the cmos rtc irq handler, or by the hpet rtc irq handler. When using ACPI RTC Fixed event as the RTC alarm, the RTC alarm is acknowledged by the ACPI RTC event handler, as addressed in the previous patch. But, when resume from suspend-to-ram (ACPI S3), the ACPI SCI is cleared right after resume, thus the ACPI RTC event handler is not invoked at all, results in the RTC Alarm unacknowledged. Handle this by comparing the current time and the RTC Alarm time in the rtc_cmos driver .resume() callback 1. Assume the wakeup event has already been fired if the RTC Alarm time is earlier than/equal to the current time, and ACK the RTC Alarm. 2. Assume the wakeup event has not been fired if the RTC Alarm time is later than current time, and re-arm it if needed. Signed-off-by: Zhang Rui <rui.zhang@intel.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-04-19rtc: cmos: allow using ACPI for RTC alarm instead of HPETZhang Rui
It's found that the HPET timer prevents the platform from entering Low Power S0 on some new Intel platforms. This means that 1. users can still use RTC wake Alarm for suspend-to-idle, but the system never enters Low Power S0, which is a waste of power. or 2. if users want to put the system into Low Power S0, they can not use RTC as the wakeup source. To fix this, we need to stop using the HPET timer for wake alarm. But disabling CONFIG_HPET_EMULATE_RTC is not an option because HPET emulates PIT at the same time, and this is needed on some of these platforms. Thus, introduce a new mode (use_acpi_alarm) to the rtc_cmos driver, so that, even with CONFIG_HPET_EMULATE_RTC enabled, it's still possible to use ACPI SCI for RTC Alarm, including UIE/AIE/wkalrm, instead of HPET. Only necessary changes are made for the new "use_acpi_alarm" mode, including 1. drop all the calls to HPET emulation code, including the HPET irq handler for rtc interrupt. 2. enabling/disabling ACPI RTC Fixed event upon RTC UIE/AIE request. 3. acknowledge the RTC Alarm in ACPI RTC Fixed event handler. There is no functional change made in this patch if the new mode is not enabled. Note: this "use_acpi_alarm" mode is made based on the assumption that ACPI RTC Fixed event is reliable both at runtime and during system wakeup. And this has been verified on a couple of platforms I have, including a MS Surface Pro 4 (SKL), a Lenovo Yoga 900 (SKL), and a HP 9360 (KBL). Signed-off-by: Zhang Rui <rui.zhang@intel.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-04-10Merge tag 'rtc-4.17' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux Pull RTC updates from Alexandre Belloni: "This contains a few series that have been in preparation for a while and that will help systems with RTCs that will fail in 2038, 2069 or 2100. Subsystem: - Add tracepoints - Rework of the RTC/nvmem API to allow drivers to discard struct nvmem_config after registration - New range API, drivers can now expose the useful range of the RTC - New offset API the core is now able to add an offset to the RTC time, modifying the supported range. - Multiple rtc_time64_to_tm fixes - Handle time_t overflow on 32 bit platforms in the core instead of letting drivers do crazy things. - remove rtc_control API New driver: - Intersil ISL12026 Drivers: - Drivers exposing the RTC non volatile memory have been converted to use nvmem - Removed useless time and date validation - Removed an indirection pattern that was a cargo cult from ancient drivers - Removed VLA usage - Fixed a possible race condition in probe functions - AB8540 support is dropped from ab8500 - pcf85363 now has alarm support" * tag 'rtc-4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (128 commits) rtc: snvs: Fix usage of snvs_rtc_enable rtc: mt7622: fix module autoloading for OF platform drivers rtc: isl12022: use true and false for boolean values rtc: ab8500: Drop AB8540 support rtc: remove a warning during scripts/kernel-doc step rtc: 88pm860x: remove artificial limitation rtc: 88pm80x: remove artificial limitation rtc: st-lpc: remove artificial limitation rtc: mrst: remove artificial limitation rtc: mv: remove artificial limitation rtc: hctosys: Ensure system time doesn't overflow time_t parisc: time: stop validating rtc_time in .read_time rtc: pcf85063: fix clearing bits in pcf85063_start_clock rtc: at91sam9: Set name of regmap_config rtc: s5m: Remove VLA usage rtc: s5m: Move enum from rtc.h to rtc-s5m.c rtc: remove VLA usage rtc: Add useful timestamp definitions rtc: Add one offset seconds to expand RTC range rtc: Factor out the RTC range validation into rtc_valid_range() ...
2018-03-09mn10300: Remove the architectureDavid Howells
Remove the MN10300 arch as the hardware is defunct. Suggested-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: David Howells <dhowells@redhat.com> cc: Masahiro Yamada <yamada.masahiro@socionext.com> cc: linux-am33-list@redhat.com Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-03-01rtc: cmos: let the core handle invalid timeAlexandre Belloni
Setting the rtc to a valid time when the time is invalid is a bad practice, because then userspace doesn't know it shouldn't trust the RTC. Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-03-01rtc: cmos: use generic nvmemAlexandre Belloni
Instead of adding a binary sysfs attribute from the driver, use the core to register an nvmem device. This allows to use the in-kernel interface to access the nvram. Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-03-01rtc: cmos: fix possible race conditionAlexandre Belloni
The probe function is not allowed to fail after registering the RTC because the following may happen: CPU0: CPU1: sys_load_module() do_init_module() do_one_initcall() cmos_do_probe() rtc_device_register() __register_chrdev() cdev->owner = struct module* open("/dev/rtc0") rtc_device_unregister() module_put() free_module() module_free(mod->module_core) /* struct module *module is now freed */ chrdev_open() spin_lock(cdev_lock) cdev_get() try_module_get() module_is_live() /* dereferences already freed struct module* */ Switch to devm_rtc_allocate_device/rtc_register_device to register the rtc as late as possible. Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2017-05-22Merge branches 'pm-sleep' and 'powercap'Rafael J. Wysocki
* pm-sleep: PM / hibernate: Declare variables as static RTC: rtc-cmos: Fix wakeup from suspend-to-idle PM / wakeup: Fix up wakeup_source_report_event() * powercap: PowerCap: Fix an error code in powercap_register_zone()
2017-05-14RTC: rtc-cmos: Fix wakeup from suspend-to-idleRafael J. Wysocki
Commit eed4d47efe95 (ACPI / sleep: Ignore spurious SCI wakeups from suspend-to-idle) modified the core suspend-to-idle code to filter out spurious SCI interrupts received while suspended, which requires ACPI event source handlers to report wakeup events in a way that will trigger a wakeup from suspend to idle (or abort system suspends in progress, which is equivalent). That needs to be done in the rtc-cmos driver too, which was overlooked by the above commit, so do that now. Fixes: eed4d47efe95 (ACPI / sleep: Ignore spurious SCI wakeups from suspend-to-idle) Reported-by: David E. Box <david.e.box@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-04-14rtc: cmos: Do not assume irq 8 for rtc when there are no legacy irqsHans de Goede
On some systems (e.g. Intel Bay Trail systems) the legacy PIC is not used, in this case virq 8 will be a random irq, rather then hw_irq 8 from the PIC. Requesting virq 8 in this case will not help us to get alarm irqs and may cause problems for other drivers which actually do need virq 8, for example on an Asus Transformer T100TA this leads to: [ 28.745155] genirq: Flags mismatch irq 8. 00000088 (mmc0) vs. 00000080 (rtc0) <snip oops> [ 28.753700] mmc0: Failed to request IRQ 8: -16 [ 28.975934] sdhci-acpi: probe of 80860F14:01 failed with error -16 This commit fixes this by making the rtc-cmos driver continue without using an irq rather then claiming irq 8 when no irq is specified in the pnp-info and there are no legacy-irqs. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-12-18Merge tag 'rtc-4.10' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux Pull RTC updates from Alexandre Belloni: "Subsystem: - non-modular drivers are now explicitly non-modular New driver: - Epson Toyocom rtc-7301sf/dg Drivers: - cmos: reject unsupported alarm values wrt the RTC capabilities - ds1307: ACPI support - jz4740: DT support, jz4780 handling, can now be used as a system power controller - mcp795: many fixes, in particular proper month handling - twl: driver is now DT only" * tag 'rtc-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (31 commits) rtc: mcp795: Fix whitespace and indentation. rtc: mcp795: Prefer using the BIT() macro. rtc: mcp795: fix month write resetting date to 1. rtc: mcp795: fix time range difference between linux and RTC chip. rtc: mcp795: fix bitmask value for leap year (LP). rtc: mcp795: use bcd2bin/bin2bcd. rtc: add support for EPSON TOYOCOM RTC-7301SF/DG rtc: ds1307: Add ACPI support rtc: imxdi: (trivial) fix a typo rtc: ds1374: Merge conditional + WARN_ON() rtc: twl: make driver DT only rtc: twl: kill static variables rtc: fix typos in Kconfig rtc: jz4740: make the driver builtin only rtc: jz4740: remove unused EXPORT_SYMBOL Documentation: bindings: fix twl-rtc documentation rtc: Enable compile testing for Maxim and Samsung drivers MIPS: jz4740: Remove obsolete code MIPS: qi_lb60: Probe RTC driver from DT and use it as power controller MIPS: jz4740: DTS: Probe the jz4740-rtc driver from devicetree ...
2016-12-12Merge branch 'timers-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer updates from Thomas Gleixner: "The time/timekeeping/timer folks deliver with this update: - Fix a reintroduced signed/unsigned issue and cleanup the whole signed/unsigned mess in the timekeeping core so this wont happen accidentaly again. - Add a new trace clock based on boot time - Prevent injection of random sleep times when PM tracing abuses the RTC for storage - Make posix timers configurable for real tiny systems - Add tracepoints for the alarm timer subsystem so timer based suspend wakeups can be instrumented - The usual pile of fixes and updates to core and drivers" * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits) timekeeping: Use mul_u64_u32_shr() instead of open coding it timekeeping: Get rid of pointless typecasts timekeeping: Make the conversion call chain consistently unsigned timekeeping_Force_unsigned_clocksource_to_nanoseconds_conversion alarmtimer: Add tracepoints for alarm timers trace: Update documentation for mono, mono_raw and boot clock trace: Add an option for boot clock as trace clock timekeeping: Add a fast and NMI safe boot clock timekeeping/clocksource_cyc2ns: Document intended range limitation timekeeping: Ignore the bogus sleep time if pm_trace is enabled selftests/timers: Fix spelling mistake "Asyncrhonous" -> "Asynchronous" clocksource/drivers/bcm2835_timer: Unmap region obtained by of_iomap clocksource/drivers/arm_arch_timer: Map frame with of_io_request_and_map() arm64: dts: rockchip: Arch counter doesn't tick in system suspend clocksource/drivers/arm_arch_timer: Don't assume clock runs in suspend posix-timers: Make them configurable posix_cpu_timers: Move the add_device_randomness() call to a proper place timer: Move sys_alarm from timer.c to itimer.c ptp_clock: Allow for it to be optional Kconfig: Regenerate *.c_shipped files after previous changes ...
2016-11-29timekeeping: Ignore the bogus sleep time if pm_trace is enabledChen Yu
Power management suspend/resume tracing (ab)uses the RTC to store suspend/resume information persistently. As a consequence the RTC value is clobbered when timekeeping is resumed and tries to inject the sleep time. Commit a4f8f6667f09 ("timekeeping: Cap array access in timekeeping_debug") plugged a out of bounds array access in the timekeeping debug code which was caused by the clobbered RTC value, but we still use the clobbered RTC value for sleep time injection into kernel timekeeping, which will result in random adjustments depending on the stored "hash" value. To prevent this keep track of the RTC clobbering and ignore the invalid RTC timestamp at resume. If the system resumed successfully clear the flag, which marks the RTC as unusable, warn the user about the RTC clobber and recommend to adjust the RTC with 'ntpdate' or 'rdate'. [jstultz: Fixed up pr_warn formating, and implemented suggestions from Ingo] [ tglx: Rewrote changelog ] Originally-from: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Chen Yu <yu.c.chen@intel.com> Signed-off-by: John Stultz <john.stultz@linaro.org> Acked-by: Pavel Machek <pavel@ucw.cz> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Prarit Bhargava <prarit@redhat.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Xunlei Pang <xlpang@redhat.com> Cc: Len Brown <lenb@kernel.org> Link: http://lkml.kernel.org/r/1480372524-15181-3-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-10-20rtc: cmos: Don't enable interrupts in the middle of the interrupt handlerVille Syrjälä
Using spin_lock_irq()/spin_unlock_irq() from within the interrupt handler is a no-no. Let's save/restore the flags to avoid turning on interrupts prematurely. We hit this in a bunch of our CI systems, but for whatever reason I wasn't able to reproduce on my own machine, so this fix is just based on the backtrace. [ 202.634918] WARNING: CPU: 0 PID: 0 at kernel/locking/lockdep.c:2729 trace_hardirqs_on_caller+0x113/0x1b0 [ 202.634919] DEBUG_LOCKS_WARN_ON(current->hardirq_context) [ 202.634929] Modules linked in: snd_hda_intel i915 x86_pkg_temp_thermal intel_powerclamp coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel lpc_ich snd_hda_codec_realtek snd_hda_codec_generic snd_hda_codec_hdmi snd_hda_codec snd_hwdep i2c_designware_platform i2c_designware_core snd_hda_core mei_me mei snd_pcm r8169 mii sdhci_acpi sdhci mmc_core i2c_hid [last unloaded: i915] [ 202.634930] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G U 4.9.0-rc1-CI-CI_DRM_1734+ #1 [ 202.634931] Hardware name: GIGABYTE M4HM87P-00/M4HM87P-00, BIOS F6 12/10/2014 [ 202.634933] ffff88011ea03d68 ffffffff8142dce5 ffff88011ea03db8 0000000000000000 [ 202.634934] ffff88011ea03da8 ffffffff8107e496 00000aa900000002 ffffffff81e249a0 [ 202.634935] ffffffff81815637 ffffffff82e7c280 0000000000000000 0000000000000004 [ 202.634936] Call Trace: [ 202.634939] <IRQ> [ 202.634939] [<ffffffff8142dce5>] dump_stack+0x67/0x92 [ 202.634941] [<ffffffff8107e496>] __warn+0xc6/0xe0 [ 202.634944] [<ffffffff81815637>] ? _raw_spin_unlock_irq+0x27/0x50 [ 202.634945] [<ffffffff8107e4fa>] warn_slowpath_fmt+0x4a/0x50 [ 202.634946] [<ffffffff810d6d83>] trace_hardirqs_on_caller+0x113/0x1b0 [ 202.634948] [<ffffffff810d6e2d>] trace_hardirqs_on+0xd/0x10 [ 202.634949] [<ffffffff81815637>] _raw_spin_unlock_irq+0x27/0x50 [ 202.634951] [<ffffffff81672042>] rtc_handler+0x32/0xa0 [ 202.634954] [<ffffffff814c08a3>] acpi_ev_fixed_event_detect+0xd4/0xfb [ 202.634956] [<ffffffff814c2ccb>] acpi_ev_sci_xrupt_handler+0xf/0x2d [ 202.634957] [<ffffffff814ab3ee>] acpi_irq+0x11/0x2c [ 202.634960] [<ffffffff810e5288>] __handle_irq_event_percpu+0x58/0x370 [ 202.634961] [<ffffffff810e55be>] handle_irq_event_percpu+0x1e/0x50 [ 202.634962] [<ffffffff810e5624>] handle_irq_event+0x34/0x60 [ 202.634963] [<ffffffff810e8906>] handle_fasteoi_irq+0xa6/0x170 [ 202.634966] [<ffffffff8101eef5>] handle_irq+0x15/0x20 [ 202.634967] [<ffffffff8101e548>] do_IRQ+0x68/0x130 [ 202.634968] [<ffffffff81816789>] common_interrupt+0x89/0x89 [ 202.634970] <EOI> [ 202.634970] [<ffffffff81814c73>] ? mwait_idle+0x93/0x210 [ 202.634971] [<ffffffff81814c6a>] ? mwait_idle+0x8a/0x210 [ 202.634972] [<ffffffff81026b0a>] arch_cpu_idle+0xa/0x10 [ 202.634973] [<ffffffff8181509e>] default_idle_call+0x1e/0x30 [ 202.634974] [<ffffffff810cbf6c>] cpu_startup_entry+0x17c/0x1f0 [ 202.634976] [<ffffffff8180ca87>] rest_init+0x127/0x130 [ 202.634978] [<ffffffff81f77f08>] start_kernel+0x3f6/0x403 [ 202.634980] [<ffffffff81f7728f>] x86_64_start_reservations+0x2a/0x2c [ 202.634981] [<ffffffff81f77404>] x86_64_start_kernel+0x173/0x186 [ 202.634982] ---[ end trace 293c99618fa08d34 ]--- Cc: Gabriele Mazzotta <gabriele.mzt@gmail.com> Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com> Fixes: 983bf1256edb ("rtc: cmos: Clear ACPI-driven alarms upon resume") Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-10-19rtc: cmos: don't refer to asm-generic/rtc.hChristoph Hellwig
That header has been gone for a while. I've fixed up the Kconfig comment, but the one in rtc-cmos.c doesn't make any sense to me even looking at its history. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-10-19rtc: cmos: Reject unsupported alarm valuesGabriele Mazzotta
Some platforms allows to specify the month and day of the month in which an alarm should go off, some others the day of the month and some others just the time. Currently any given value is accepted by the driver and only the supported fields are used to program the hardware. As consequence, alarms are potentially programmed to go off in the wrong moment. Fix this by rejecting any unsupported value. Signed-off-by: Gabriele Mazzotta <gabriele.mzt@gmail.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-10-19rtc: cmos: remove all __exit_p annotationsLABBE Corentin
I got the following stack trace under qemu: [ 7.575243] BUG: unable to handle kernel NULL pointer dereference at 0000000000000010 [ 7.596098] IP: [<ffffffff814f5b08>] cmos_set_alarm+0x38/0x280 [ 7.615699] PGD 3ccbe067 [ 7.615923] PUD 3daf2067 [ 7.635156] PMD 0 [ 7.654358] Oops: 0000 [#1] SMP [ 7.673869] Modules linked in: [ 7.693235] CPU: 0 PID: 1701 Comm: hwclock Tainted: G W 4.9.0-rc1+ #24 [ 7.712455] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.3-0-ge2fc41e-prebuilt.qemu-project.org 04/01/2014 [ 7.753569] task: ffff88003d88dc40 task.stack: ffffc90000224000 [ 7.773743] RIP: 0010:[<ffffffff814f5b08>] [<ffffffff814f5b08>] cmos_set_alarm+0x38/0x280 [ 7.794893] RSP: 0018:ffffc90000227c10 EFLAGS: 00010296 [ 7.815890] RAX: 000000000000001d RBX: ffffc90000227d28 RCX: ffffffff8182be78 [ 7.836057] RDX: 0000000000000001 RSI: 0000000000000202 RDI: 0000000000000202 [ 7.856612] RBP: ffffc90000227c48 R08: 0000000000000000 R09: 0000000000000001 [ 7.877561] R10: 00000000000001c0 R11: 00000000000001c0 R12: 0000000000000000 [ 7.897072] R13: ffff88003d96f400 R14: ffff88003dac6410 R15: ffff88003dac6420 [ 7.917403] FS: 00007f77f42d9700(0000) GS:ffff88003fc00000(0000) knlGS:0000000000000000 [ 7.938293] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 7.958364] CR2: 0000000000000010 CR3: 000000003ccbb000 CR4: 00000000000006f0 [ 7.978028] Stack: [ 7.997120] ffff88003dac6000 ffff88003dac6410 0000000058049d01 ffffc90000227d28 [ 8.016993] ffff88003dac6000 ffff88003dac6410 ffff88003dac6420 ffffc90000227c98 [ 8.039505] ffffffff814f225d 0000001800227c98 000000090000002a 0000000900000011 [ 8.059985] Call Trace: [ 8.080110] [<ffffffff814f225d>] __rtc_set_alarm+0x8d/0xa0 [ 8.099421] [<ffffffff814f2389>] rtc_timer_enqueue+0x119/0x190 [ 8.119925] [<ffffffff814f2e6e>] rtc_update_irq_enable+0xbe/0x100 [ 8.140583] [<ffffffff814f3bb0>] rtc_dev_ioctl+0x3c0/0x480 [ 8.161162] [<ffffffff81146b6a>] ? user_path_at_empty+0x3a/0x50 [ 8.182717] [<ffffffff8114aa36>] do_vfs_ioctl+0x96/0x5c0 [ 8.204624] [<ffffffff8113e066>] ? vfs_stat+0x16/0x20 [ 8.225994] [<ffffffff8113e135>] ? SyS_newstat+0x15/0x30 [ 8.247043] [<ffffffff8114afa7>] SyS_ioctl+0x47/0x80 [ 8.267191] [<ffffffff815f5c77>] entry_SYSCALL_64_fastpath+0x1a/0xa9 [ 8.288719] Code: 6a 81 48 89 e5 41 57 41 56 41 55 49 89 fd 41 54 53 48 89 f3 48 c7 c6 20 c4 78 81 48 83 ec 10 e8 8f 00 ef ff 4d 8b a5 a0 00 00 00 <41> 8b 44 24 10 85 c0 0f 8e 2b 02 00 00 4c 89 ef 31 c0 b9 53 01 [ 8.335233] RIP [<ffffffff814f5b08>] cmos_set_alarm+0x38/0x280 [ 8.357096] RSP <ffffc90000227c10> [ 8.379051] CR2: 0000000000000010 [ 8.401736] ---[ end trace 5cbcd83a1f225ed3 ]--- This occur only when CONFIG_DEBUG_TEST_DRIVER_REMOVE is enabled and CONFIG_RTC_DRV_CMOS builtin. When cmos_set_alarm() is called dev is NULL and so trigger the deref via cmos->irq The problem comes from that the device is removed but no remove function are called due to _exit_p(). This patch remove all _exit_p() annotation. Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-09-22rtc: cmos: avoid unused function warningArnd Bergmann
A bug fix for the ACPI side of this driver caused a harmless build warning: drivers/rtc/rtc-cmos.c:1115:13: error: 'cmos_check_acpi_rtc_status' defined but not used [-Werror=unused-function] static void cmos_check_acpi_rtc_status(struct device *dev, We can avoid the warning and simplify the driver at the same time by removing the #ifdef for CONFIG_PM and rely on the SIMPLE_DEV_PM_OPS() to set everything up correctly. cmos_resume() has to get marked as __maybe_unused so we don't introduce another warning, and the two variants of cmos_poweroff() can get merged into one using an IS_ENABLED() check. Fixes: 983bf1256edb ("rtc: cmos: Clear ACPI-driven alarms upon resume") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-09-21rtc: cmos: Restore alarm after resumeGabriele Mazzotta
Some platform firmware may interfere with the RTC alarm over suspend, resulting in the kernel and hardware having different ideas about system state but also potentially causing problems with firmware that assumes the OS will clean this case up. This patch restores the RTC alarm on resume to ensure that kernel and hardware are in sync. The case we've seen is Intel Rapid Start, which is a firmware-mediated feature that automatically transitions systems from suspend-to-RAM to suspend-to-disk without OS involvement. It does this by setting the RTC alarm and a flag that indicates that on wake it should perform the transition rather than re-starting the OS. However, if the OS has set a wakeup alarm that would wake the machine earlier, it refuses to overwrite it and allows the system to wake instead. This fails in the following situation: 1) User configures Intel Rapid Start to transition after (say) 15 minutes 2) User suspends to RAM. Firmware sets the wakeup alarm for 15 minutes in the future 3) User resumes after 5 minutes. Firmware does not reset the alarm, and as such it is still set for 10 minutes in the future 4) User suspends after 5 minutes. Firmware notices that the alarm is set for 5 minutes in the future, which is less than the 15 minute transition threshold. It therefore assumes that the user wants the machine to wake in 5 minutes 5) System resumes after 5 minutes The worst case scenario here is that the user may have put the system in a bag between (4) and (5), resulting in it running in a confined space and potentially overheating. This seems reasonably important. The Rapid Start support code got added in 3.11, but it can be configured in the firmware regardless of kernel support. Signed-off-by: Gabriele Mazzotta <gabriele.mzt@gmail.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-09-21rtc: cmos: Clear ACPI-driven alarms upon resumeGabriele Mazzotta
Currently ACPI-driven alarms are not cleared when they wake the system. As consequence, expired alarms must be manually cleared to program a new alarm. Fix this by correctly handling ACPI-driven alarms. More specifically, the ACPI specification [1] provides for two alternative implementations of the RTC. Depending on the implementation, the driver either clear the alarm from the resume callback or from ACPI interrupt handler: - The platform has the RTC wakeup status fixed in hardware (ACPI_FADT_FIXED_RTC is 0). In this case the driver can determine if the RTC was the reason of the wakeup from the resume callback by reading the RTC status register. - The platform has no fixed hardware feature event bits. In this case a GPE is used to wake the system and the driver clears the alarm from its handler. [1] http://www.acpi.info/DOWNLOADS/ACPI_5_Errata%20A.pdf Signed-off-by: Gabriele Mazzotta <gabriele.mzt@gmail.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-09-20rtc: cmos: Initialize hpet timer before irq is registeredPratyush Anand
We have observed on few x86 machines with rtc-cmos device that hpet_rtc_interrupt() is called just after irq registration and before cmos_do_probe() could call hpet_rtc_timer_init(). So, neither hpet_default_delta nor hpet_t1_cmp is initialized by the time interrupt is raised in the given situation, and this results in NMI watchdog LOCKUP. It has only been observed sporadically on kdump secondary kernels. See the call trace: ---<-snip->--- [ 27.913194] Kernel panic - not syncing: Watchdog detected hard LOCKUP on cpu 0 [ 27.915371] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.10.0-342.el7.x86_64 #1 [ 27.917503] Hardware name: HP ProLiant DL160 Gen8, BIOS J03 02/10/2014 [ 27.919455] ffffffff8186a728 0000000059c82488 ffff880034e05af0 ffffffff81637bd4 [ 27.921870] ffff880034e05b70 ffffffff8163144a 0000000000000010 ffff880034e05b80 [ 27.924257] ffff880034e05b20 0000000059c82488 0000000000000000 0000000000000000 [ 27.926599] Call Trace: [ 27.927352] <NMI> [<ffffffff81637bd4>] dump_stack+0x19/0x1b [ 27.929080] [<ffffffff8163144a>] panic+0xd8/0x1e7 [ 27.930588] [<ffffffff8111d3e0>] ? restart_watchdog_hrtimer+0x50/0x50 [ 27.932502] [<ffffffff8111d4a2>] watchdog_overflow_callback+0xc2/0xd0 [ 27.934427] [<ffffffff811612c1>] __perf_event_overflow+0xa1/0x250 [ 27.936232] [<ffffffff81161d94>] perf_event_overflow+0x14/0x20 [ 27.937957] [<ffffffff81032ae8>] intel_pmu_handle_irq+0x1e8/0x470 [ 27.939799] [<ffffffff8164164b>] perf_event_nmi_handler+0x2b/0x50 [ 27.941649] [<ffffffff81640d99>] nmi_handle.isra.0+0x69/0xb0 [ 27.943348] [<ffffffff81640f49>] do_nmi+0x169/0x340 [ 27.944802] [<ffffffff816401d3>] end_repeat_nmi+0x1e/0x2e [ 27.946424] [<ffffffff81056ee5>] ? hpet_rtc_interrupt+0x85/0x380 [ 27.948197] [<ffffffff81056ee5>] ? hpet_rtc_interrupt+0x85/0x380 [ 27.949992] [<ffffffff81056ee5>] ? hpet_rtc_interrupt+0x85/0x380 [ 27.951816] <<EOE>> <IRQ> [<ffffffff8108f5a3>] ? run_timer_softirq+0x43/0x340 [ 27.954114] [<ffffffff8111e24e>] handle_irq_event_percpu+0x3e/0x1e0 [ 27.955962] [<ffffffff8111e42d>] handle_irq_event+0x3d/0x60 [ 27.957635] [<ffffffff811210c7>] handle_edge_irq+0x77/0x130 [ 27.959332] [<ffffffff8101704f>] handle_irq+0xbf/0x150 [ 27.960949] [<ffffffff8164a86f>] do_IRQ+0x4f/0xf0 [ 27.962434] [<ffffffff8163faed>] common_interrupt+0x6d/0x6d [ 27.964101] <EOI> [<ffffffff8163f43b>] ? _raw_spin_unlock_irqrestore+0x1b/0x40 [ 27.966308] [<fffff8111ff07>] __setup_irq+0x2a7/0x570 [ 28.067859] [<ffffffff81056e60>] ? hpet_cpuhp_notify+0x140/0x140 [ 28.069709] [<ffffffff8112032c>] request_threaded_irq+0xcc/0x170 [ 28.071585] [<ffffffff814b24a6>] cmos_do_probe+0x1e6/0x450 [ 28.073240] [<ffffffff814b2710>] ? cmos_do_probe+0x450/0x450 [ 28.074911] [<ffffffff814b27cb>] cmos_pnp_probe+0xbb/0xc0 [ 28.076533] [<ffffffff8139b245>] pnp_device_probe+0x65/0xd0 [ 28.078198] [<ffffffff813f8ca7>] driver_probe_device+0x87/0x390 [ 28.079971] [<ffffffff813f9083>] __driver_attach+0x93/0xa0 [ 28.081660] [<ffffffff813f8ff0>] ? __device_attach+0x40/0x40 [ 28.083662] [<ffffffff813f6a13>] bus_for_each_dev+0x73/0xc0 [ 28.085370] [<ffffffff813f86fe>] driver_attach+0x1e/0x20 [ 28.086974] [<ffffffff813f8250>] bus_add_driver+0x200/0x2d0 [ 28.088634] [<ffffffff81ade49a>] ? rtc_sysfs_init+0xe/0xe [ 28.090349] [<ffffffff813f9704>] driver_register+0x64/0xf0 [ 28.091989] [<ffffffff8139b070>] pnp_register_driver+0x20/0x30 [ 28.093707] [<ffffffff81ade4ab>] cmos_init+0x11/0x71 ---<-snip->--- This patch moves hpet_rtc_timer_init() before IRQ registration, so that we can gracefully handle such spurious interrupts. It also masks HPET RTC interrupts, in case IRQ registration fails. We were able to reproduce the problem in maximum 15 trials of kdump secondary kernel boot on an hp-dl160gen8 FCoE host machine without this patch. However, more than 35 trials went fine after applying this patch. Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Pratyush Anand <panand@redhat.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-07-09rtc: simplify implementations of read_alarmUwe Kleine-König
Since commit d68778b80dd7 ("rtc: initialize output parameter for read alarm to "uninitialized"") there is no need to explicitly set unsupported members to -1. So drop the respective assignments from drivers. Signed-off-by: Uwe Kleine-König <uwe@kleine-koenig.org> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-06-26mn10300: use RTC_DRV_CMOS instead of CONFIG_RTCArnd Bergmann
nn10300 has a dependency on mc146818_get_time/mc146818_set_time, which we want to move from the mc146818rtc.h header into the rtc subsystem, which in turn is not usable on mn10300. This changes mn10300 to use the modern rtc-cmos driver instead of the old RTC driver, and that in turn lets us completely remove the read_persistent_clock/update_persistent_clock callbacks. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-06-04rtc: cmos: move mc146818rtc code out of asm-generic/rtc.hArnd Bergmann
Drivers should not really include stuff from asm-generic directly, and the PC-style cmos rtc driver does this in order to reuse the mc146818 implementation of get_rtc_time/set_rtc_time rather than the architecture specific one for the architecture it gets built for. To make it more obvious what is going on, this moves and renames the two functions into include/linux/mc146818rtc.h, which holds the other mc146818 specific code. Ideally it would be in a .c file, but that would require extra infrastructure as the functions are called by multiple drivers with conflicting dependencies. With this change, the asm-generic/rtc.h header also becomes much more generic, so it can be reused more easily across any architecture that still relies on the genrtc driver. The only caller of the internal __get_rtc_time/__set_rtc_time functions is in arch/alpha/kernel/rtc.c, and we just change those over to the new naming. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-05-20rtc: Use IS_ENABLED() instead of checking for built-in or moduleJavier Martinez Canillas
The IS_ENABLED() macro checks if a Kconfig symbol has been enabled either built-in or as a module, use that macro instead of open coding the same. Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-01-11rtc: cmos: prevent kernel warning on IRQ flags mismatchAndy Shevchenko
The Microsoft Surface 3 tablet shares interrupt line between RTC and one of SPI controllers. However, the rtc_cmos driver doesn't allow shared interrupts and user sees the following warning genirq: Flags mismatch irq 8. 00000080 (8086228E:02) vs. 00000000 (rtc0) ... [<ffffffffa004eb01>] pxa2xx_spi_probe+0x151/0x600 [spi_pxa2xx_platform] Allow RTC driver to use shared interrupts. Seems we are on the safe side to do just this simple change since cmos_interrupt() handler checks for the actual hardware status anyway. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2015-09-05rtc: cmos: clean up cmos_nvram_read()/cmos_nvram_write()Vladimir Zapolskiy
The change removes redundant sysfs binary file boundary checks, since this task is already done on caller side in fs/sysfs/file.c Signed-off-by: Vladimir Zapolskiy <vz@mleia.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2015-09-05rtc: cmos: Revert "rtc-cmos: Add an alarm disable quirk"Adrian Huang
Commit d5a1c7e3fc38 ("rtc-cmos: Add an alarm disable quirk") that added a special quirk is not needed because [PATCH 1/2] of this patchset makes the kernel more robust: rtc-cmos: Cancel alarm timer if alarm time is equal to now+1 seconds Signed-off-by: Adrian Huang <ahuang12@lenovo.com> Tested-by: Egbert Eich <eich@suse.de> Tested-by: Diego Ercolani <diego.ercolani@gmail.com> Cc: Borislav Petkov <bp@suse.de> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2015-09-05rtc: cmos: Cancel alarm timer if alarm time is equal to now+1 secondsAdrian Huang
Steps to reproduce the problem: 1) Enable RTC wake-up option in BIOS Setup 2) Issue one of these commands in the OS: "poweroff" or "shutdown -h now" 3) System will shut down and then reboot automatically Root-cause of the issue: 1) During the shutdown process, the hwclock utility is used to save the system clock to hardware clock (RTC). 2) The hwclock utility invokes ioctl() with RTC_UIE_ON. The kernel configures the RTC alarm for the periodic interrupt (every 1 second). 3) The hwclock uitlity closes the /dev/rtc0 device, and the kernel disables the RTC alarm irq (AIE bit of Register B) via ioctl() with RTC_UIE_OFF. But, the configured alarm time is the current_time + 1. 4) After the next 1 second is elapsed, the AF (alarm interrupt flag) of Register C is set. 5) The S5 handler in BIOS is invoked to configure alarm registers (enable AIE bit and configure alarm date/time). But, BIOS does not clear the previous interrupt status during alarm configuration. Therefore, "AF=AIE=1" causes the rtc device to trigger an interrupt. 6) So, the machine reboots automatically right after shutdown. This patch cancels the alarm timer if the following condictions are met (suggested by Alexandre): 1) The configured alarm time is equal to current_time + 1 seconds. 2) The AIE timer is not in use. The member 'alarm_expires' is introduced in struct cmos_rtc because of the following reasons: 1) The configured alarm time can be retrieved from cmos_read_alarm(), but we need to take the 'wrapped timestamp' and 'time rollover' into consideration. The function __rtc_read_alarm() eliminates the concerns. To avoid the duplicated code in the lower level RTC driver, invoking __rtc_read_alarm from the lower level RTC driver is not encouraged. Moreover, the compilation error 'the undefined __rtc_read_alarm" is observed if the lower level RTC driver is compiled as a kernel module. 2) The uie_rtctimer.node.expires and aie_timer.node.expires can be retrieved for the configured alarm time. But, the problem is that either of them might configure the CMOS alarm time. We cannot make sure UIE timer or AIE tiemr configured the CMOS alarm time before. (uie_rtctimer or aie_timer is enabled and then is disabled). 3) The patch introduces the member 'alarm_expires' to keep the newly configured alarm time, so the above-mentioned concerns can be eliminated. The issue goes away after 20-time shutdown tests. Signed-off-by: Adrian Huang <ahuang12@lenovo.com> Tested-by: Egbert Eich <eich@suse.de> Tested-by: Diego Ercolani <diego.ercolani@gmail.com> Cc: Borislav Petkov <bp@suse.de> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2015-04-17rtc: use more standard kernel logging stylesJoe Perches
Neaten the logging a bit by adding #define pr_fmt Miscellanea: o Remove __FILE__/__func__ uses o Coalesce formats adding missing spaces o Align arguments o (rtc-cmos) Integrated 2 consecutive messages Signed-off-by: Joe Perches <joe@perches.com> Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Joshua Kinard <kumba@gentoo.org> Cc: Chanwoo Choi <cw00.choi@samsung.com> Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Tested-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Cc: Aaro Koskinen <aaro.koskinen@iki.fi> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-15rtc: remove use of seq_printf return valueJoe Perches
The seq_printf return value, because it's frequently misused, will eventually be converted to void. See: commit 1f33c41c03da ("seq_file: Rename seq_overflow() to seq_has_overflowed() and make public") Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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