Fix the following warnings:
drivers/rtc/rtc-ds1685.c: In function ‘ds1685_rtc_read_time’:
drivers/rtc/rtc-ds1685.c:264:5: warning: variable ‘ctrlb’ set but not used [-Wunused-but-set-variable]
264 | u8 ctrlb, century;
| ^~~~~
drivers/rtc/rtc-ds1685.c: In function ‘ds1685_rtc_proc’:
drivers/rtc/rtc-ds1685.c:758:19: warning: variable ‘ctrlc’ set but not used [-Wunused-but-set-variable]
758 | u8 ctrla, ctrlb, ctrlc, ctrld, ctrl4a, ctrl4b, ssn[8];
| ^~~~~
Cc: Joshua Kinard <kumba@gentoo.org>
Acked-By: Joshua Kinard <kumba@gentoo.org>
Link: https://lore.kernel.org/r/20191122102212.400158-4-alexandre.belloni@bootlin.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Fix undocumented function parameters:
drivers/rtc/sysfs.c:112: warning: Function parameter or member 'dev' not described in 'hctosys_show'
drivers/rtc/sysfs.c:112: warning: Function parameter or member 'attr' not described in 'hctosys_show'
drivers/rtc/sysfs.c:112: warning: Function parameter or member 'buf' not described in 'hctosys_show'
Link: https://lore.kernel.org/r/20191122102212.400158-2-alexandre.belloni@bootlin.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Fix kerneldoc warnings:
drivers/rtc/interface.c:619: warning: Function parameter or member 'num' not described in 'rtc_handle_legacy_irq'
drivers/rtc/interface.c:619: warning: Function parameter or member 'mode' not described in 'rtc_handle_legacy_irq'
drivers/rtc/interface.c:804: warning: Function parameter or member 'rtc' not described in 'rtc_timer_enqueue'
drivers/rtc/interface.c:804: warning: Function parameter or member 'timer' not described in 'rtc_timer_enqueue'
drivers/rtc/interface.c:864: warning: Function parameter or member 'rtc' not described in 'rtc_timer_remove'
drivers/rtc/interface.c:864: warning: Function parameter or member 'timer' not described in 'rtc_timer_remove'
drivers/rtc/interface.c:900: warning: Function parameter or member 'work' not described in 'rtc_timer_do_work'
drivers/rtc/interface.c:1035: warning: Function parameter or member 'rtc' not described in 'rtc_read_offset'
drivers/rtc/interface.c:1035: warning: Function parameter or member 'offset' not described in 'rtc_read_offset'
drivers/rtc/interface.c:1070: warning: Function parameter or member 'rtc' not described in 'rtc_set_offset'
drivers/rtc/interface.c:1070: warning: Function parameter or member 'offset' not described in 'rtc_set_offset'
Link: https://lore.kernel.org/r/20191127082932.666869-1-alexandre.belloni@bootlin.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
The msm6242_set()/msm6242_clear() functions are used when writing to Control
Register D to set or clear the HOLD bit when reading the current time from
the RTC.
Doing this with a read-modify-write cycle will potentially clear an
interrupt condition which occurs between the read and the write.
The datasheet states the following about this:
When writing the HOLD or 30 second adjust bits of register D, it is
necessary to write the IRQ FLAG bit to a "1".
Since the only other bits in the register are the 30 second adjust bit
(which is not used) and the BUSY bit (which is read-only), the
read-modify-write cycle can be replaced by a simple write with the IRQ FLAG
bit set to 1 and the other bits (except HOLD) set to 0.
Tested-by: Kars de Jong <jongk@linux-m68k.org>
Signed-off-by: Kars de Jong <jongk@linux-m68k.org>
Link: https://lore.kernel.org/r/20191116114620.9193-1-jongk@linux-m68k.org
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
When using following operations:
date -s "21190910 19:20:00"
hwclock -w
to change date from 2019 to 2119 for test, it will fail on Hygon
Dhyana and AMD Zen CPUs, while the same operations run ok on Intel i7
platform.
MC146818 driver use function mc146818_set_time() to set register
RTC_FREQ_SELECT(RTC_REG_A)'s bit4-bit6 field which means divider stage
reset value on Intel platform to 0x7.
While AMD/Hygon RTC_REG_A(0Ah)'s bit4 is defined as DV0 [Reference]:
DV0 = 0 selects Bank 0, DV0 = 1 selects Bank 1. Bit5-bit6 is defined
as reserved.
DV0 is set to 1, it will select Bank 1, which will disable AltCentury
register(0x32) access. As UEFI pass acpi_gbl_FADT.century 0x32
(AltCentury), the CMOS write will be failed on code:
CMOS_WRITE(century, acpi_gbl_FADT.century).
Correct RTC_REG_A bank select bit(DV0) to 0 on AMD/Hygon CPUs, it will
enable AltCentury(0x32) register writing and finally setup century as
expected.
Test results on Intel i7, AMD EPYC(17h) and Hygon machine show that it
works as expected.
Compiling for sparc64 and alpha architectures are passed.
Reference:
https://www.amd.com/system/files/TechDocs/51192_Bolton_FCH_RRG.pdf
section: 3.13 Real Time Clock (RTC)
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Jinke Fan <fanjinke@hygon.cn>
Link: https://lore.kernel.org/r/20191105083943.115320-1-fanjinke@hygon.cn
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
When setting the time in the future with the uie timer enabled,
rtc_timer_do_work will loop for a while because the expiration of the uie
timer was way before the current RTC time and a new timer will be enqueued
until the current rtc time is reached.
If the uie timer is enabled, disable it before setting the time and enable
it after expiring current timers (which may actually be an alarm).
This is the safest thing to do to ensure the uie timer is still
synchronized with the RTC, especially in the UIE emulation case.
Reported-by: syzbot+08116743f8ad6f9a6de7@syzkaller.appspotmail.com
Fixes: 6610e0893b ("RTC: Rework RTC code to use timerqueue for events")
Link: https://lore.kernel.org/r/20191020231320.8191-1-alexandre.belloni@bootlin.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
All watchdog drivers implement the same set of ioctl commands, and
fortunately all of them are compatible between 32-bit and 64-bit
architectures.
Modern drivers always go through drivers/watchdog/wdt.c as an abstraction
layer, but older ones implement their own file_operations on a character
device for this.
Move the handling from fs/compat_ioctl.c into the individual drivers.
Note that most of the legacy drivers will never be used on 64-bit
hardware, because they are for an old 32-bit SoC implementation, but
doing them all at once is safer than trying to guess which ones do
or do not need the compat_ioctl handling.
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
We no longer need the rtc compat handling to be in common code, now that
all drivers are either moved to the rtc-class framework, or (rarely)
exist in drivers/char for architectures without compat mode (m68k,
alpha and ia64, respectively).
I checked the list of ioctl commands in drivers, and the ones that are
not already handled are all compatible, again with the one exception of
m68k driver, which implements RTC_PLL_GET and RTC_PLL_SET, but has no
compat mode.
Unlike earlier versions of this patch, I'm now adding a separate
compat_ioctl handler that takes care of RTC_IRQP_READ32/RTC_IRQP_SET32
and treats all other commands as compatible, leaving the native
behavior unchanged.
The old conversion handler also deals with RTC_EPOCH_READ and
RTC_EPOCH_SET, which are not handled in rtc-dev.c but only in a single
device driver (rtc-vr41xx), so I'm adding the compat version in the same
place. I don't expect other drivers to need those commands in the future.
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Reviewed-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
v4: handle RTC_EPOCH_SET32 in rtc_dev_compat_ioctl
v3: handle RTC_IRQP_READ32/RTC_IRQP_SET32 in rtc_dev_compat_ioctl
v2: merge compat handler into ioctl function to avoid the
compat_alloc_user_space() roundtrip, based on feedback
from Al Viro.
Rework the interrupt handling to avoid caching the values as the core is
already doing that. The core also always ensures the rtc_time passed for
the alarm is fully populated.
The only trick is in read_alarm where status needs to be read before the
alarm registers to ensure the potential irq is not cleared.
Link: https://lore.kernel.org/r/20191019204941.6203-8-alexandre.belloni@bootlin.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
