2653 Commits

Author SHA1 Message Date
Chen-Yu Tsai
9a473d3bd9 rtc: pcf8563: Clear event flags and disable interrupts before requesting irq
[ Upstream commit 3572e8aea3bf925dac1dbf86127657c39fe5c254 ]

Besides the alarm, the PCF8563 also has a timer triggered interrupt.
In cases where the previous system left the timer and interrupts on,
or somehow the bits got enabled, the interrupt would keep triggering
as the kernel doesn't know about it.

Clear both the alarm and timer event flags, and disable the interrupts,
before requesting the interrupt line.

Fixes: ede3e9d47cca ("drivers/rtc/rtc-pcf8563.c: add alarm support")
Fixes: a45d528aab8b ("rtc: pcf8563: clear expired alarm at boot time")
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-27 14:46:38 +01:00
Chen-Yu Tsai
59010f8ca3 rtc: pcf8563: Fix interrupt trigger method
[ Upstream commit 65f662cbf829834fa4d94190eb7691e5a9cb92d8 ]

The PCF8563 datasheet says the interrupt line is active low and stays
active until the events are cleared, i.e. a level trigger interrupt.

Fix the flags used to request the interrupt.

Fixes: ede3e9d47cca ("drivers/rtc/rtc-pcf8563.c: add alarm support")
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-27 14:46:38 +01:00
Colin Ian King
814b711f62 rtc: pm8xxx: fix unintended sign extension
[ Upstream commit e42280886018c6f77f0a90190f7cba344b0df3e0 ]

Shifting a u8 by 24 will cause the value to be promoted to an integer. If
the top bit of the u8 is set then the following conversion to an unsigned
long will sign extend the value causing the upper 32 bits to be set in
the result.

Fix this by casting the u8 value to an unsigned long before the shift.

Detected by CoverityScan, CID#1309693 ("Unintended sign extension")

Fixes: 9a9a54ad7aa2 ("drivers/rtc: add support for Qualcomm PMIC8xxx RTC")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-27 14:46:18 +01:00
Colin Ian King
6518484b92 rtc: 88pm80x: fix unintended sign extension
[ Upstream commit fb0b322537a831b5b0cb948c56f8f958ce493d3a ]

Shifting a u8 by 24 will cause the value to be promoted to an integer. If
the top bit of the u8 is set then the following conversion to an unsigned
long will sign extend the value causing the upper 32 bits to be set in
the result.

Fix this by casting the u8 value to an unsigned long before the shift.

Detected by CoverityScan, CID#714646-714649 ("Unintended sign extension")

Fixes: 2985c29c1964 ("rtc: Add rtc support to 88PM80X PMIC")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-27 14:46:17 +01:00
Colin Ian King
3726373c3f rtc: 88pm860x: fix unintended sign extension
[ Upstream commit dc9e47160626cdb58d5c39a4f43dcfdb27a5c004 ]

Shifting a u8 by 24 will cause the value to be promoted to an integer. If
the top bit of the u8 is set then the following conversion to an unsigned
long will sign extend the value causing the upper 32 bits to be set in
the result.

Fix this by casting the u8 value to an unsigned long before the shift.

Detected by CoverityScan, CID#144925-144928 ("Unintended sign extension")

Fixes: 008b30408c40 ("mfd: Add rtc support to 88pm860x")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-27 14:46:17 +01:00
Uwe Kleine-König
0b9eaf82c2 rtc: ds1307: rx8130: Fix alarm handling
[ Upstream commit 3f929cad943380370b6db31fcb7a38d898d91089 ]

When the EXTENSION.WADA bit is set, register 0x19 contains a bitmap of
week days, not a day of month. As Linux only handles a single alarm
without repetition using day of month is more flexible, so clear this
bit. (Otherwise a value depending on time.tm_wday would have to be
written to register 0x19.)

Also optimize setting the AIE bit to use a single register write instead
of a bulk write of three registers.

Fixes: ee0981be7704 ("rtc: ds1307: Add support for Epson RX8130CE")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-27 14:46:17 +01:00
Colin Ian King
7d7e9d2378 rtc: ds1672: fix unintended sign extension
[ Upstream commit f0c04c276739ed8acbb41b4868e942a55b128dca ]

Shifting a u8 by 24 will cause the value to be promoted to an integer. If
the top bit of the u8 is set then the following conversion to an unsigned
long will sign extend the value causing the upper 32 bits to be set in
the result.

Fix this by casting the u8 value to an unsigned long before the shift.

Detected by CoverityScan, CID#138801 ("Unintended sign extension")

Fixes: edf1aaa31fc5 ("[PATCH] RTC subsystem: DS1672 driver")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-27 14:46:17 +01:00
Eric Wong
50e12e2be9 rtc: cmos: ignore bogus century byte
[ Upstream commit 2a4daadd4d3e507138f8937926e6a4df49c6bfdc ]

Older versions of Libreboot and Coreboot had an invalid value
(`3' in my case) in the century byte affecting the GM45 in
the Thinkpad X200.  Not everybody's updated their firmwares,
and Linux <= 4.2 was able to read the RTC without problems,
so workaround this by ignoring invalid values.

Fixes: 3c217e51d8a272b9 ("rtc: cmos: century support")

Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Sylvain Chouleur <sylvain.chouleur@intel.com>
Cc: Patrick McDermott <patrick.mcdermott@libiquity.com>
Cc: linux-rtc@vger.kernel.org
Signed-off-by: Eric Wong <e@80x24.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-27 14:46:14 +01:00
Kars de Jong
4e1f6dfffa rtc: msm6242: Fix reading of 10-hour digit
commit e34494c8df0cd96fc432efae121db3212c46ae48 upstream.

The driver was reading the wrong register as the 10-hour digit due to
a misplaced ')'. It was in fact reading the 1-second digit register due
to this bug.

Also remove the use of a magic number for the hour mask and use the define
for it which was already present.

Fixes: 4f9b9bba1dd1 ("rtc: Add an RTC driver for the Oki MSM6242")
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/20191116110548.8562-1-jongk@linux-m68k.org
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-17 19:45:52 +01:00
Ran Bi
f1545409a5 rtc: mt6397: fix alarm register overwrite
commit 653997eeecef95c3ead4fba1b2d27e6a5854d6cd upstream.

Alarm registers high byte was reserved for other functions.
This add mask in alarm registers operation functions.
This also fix error condition in interrupt handler.

Fixes: fc2979118f3f ("rtc: mediatek: Add MT6397 RTC driver")

Signed-off-by: Ran Bi <ran.bi@mediatek.com>
Signed-off-by: Hsin-Hsiung Wang <hsin-hsiung.wang@mediatek.com>
Link: https://lore.kernel.org/r/1576057435-3561-6-git-send-email-hsin-hsiung.wang@mediatek.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-17 19:45:44 +01:00
Christophe JAILLET
aa3baaae55 rtc: max8997: Fix the returned value in case of error in 'max8997_rtc_read_alarm()'
[ Upstream commit 41ef3878203cd9218d92eaa07df4b85a2cb128fb ]

In case of error, we return 0.
This is spurious and not consistent with the other functions of the driver.
Propagate the error code instead.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-12-17 20:38:03 +01:00
Marek Szyprowski
d4e3d38b90 rtc: s3c-rtc: Avoid using broken ALMYEAR register
[ Upstream commit 50c8aec4212a966817e868056efc9bfbb73337c0 ]

(RTC,ALM)YEAR registers of Exynos built-in RTC device contains 3 BCD
characters. s3c-rtc driver uses only 2 lower of them and supports years
from 2000..2099 range. The third BCD value is typically set to 0, but it
looks that handling of it is broken in the hardware. It sometimes
defaults to a random (even non-BCD) value. This is not an issue
for handling RTCYEAR register, because bcd2bin() properly handles only
8bit values (2 BCD characters, the third one is skipped). The problem
is however with ALMYEAR register and proper RTC alarm operation. When
YEAREN bit is set for the configured alarm, RTC hardware triggers alarm
only when ALMYEAR and RTCYEAR matches. This usually doesn't happen
because of the random noise on the third BCD character.

Fix this by simply skipping setting ALMYEAR register in alarm
configuration. This workaround fixes broken alarm operation on Exynos
built-in rtc device. My tests revealed that the issue happens on the
following Exynos series: 3250, 4210, 4412, 5250 and 5410.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-12-17 20:37:45 +01:00
Nathan Chancellor
3a17e015ec rtc: s35390a: Change buf's type to u8 in s35390a_init
[ Upstream commit ef0f02fd69a02b50e468a4ddbe33e3d81671e248 ]

Clang warns:

drivers/rtc/rtc-s35390a.c:124:27: warning: implicit conversion from
'int' to 'char' changes value from 192 to -64 [-Wconstant-conversion]
        buf = S35390A_FLAG_RESET | S35390A_FLAG_24H;
            ~ ~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~
1 warning generated.

Update buf to be an unsigned 8-bit integer, which matches the buf member
in struct i2c_msg.

https://github.com/ClangBuiltLinux/linux/issues/145
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-12-01 09:13:44 +01:00
Alexandre Belloni
23acf86994 rtc: armada38x: fix possible race condition
[ Upstream commit 7d61cbb945a753af08e247b5f10bdd5dbb8d6c80 ]

The IRQ is requested before the struct rtc is allocated and registered, but
this struct is used in the IRQ handler. This may lead to a NULL pointer
dereference.

Switch to devm_rtc_allocate_device/rtc_register_device to allocate the rtc
before requesting the IRQ.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-11-20 18:00:51 +01:00
Alexandre Belloni
c07f8f5046 rtc: pl030: fix possible race condition
[ Upstream commit c778ec85825dc895936940072aea9fe9037db684 ]

The IRQ is requested before the struct rtc is allocated and registered, but
this struct is used in the IRQ handler. This may lead to a NULL pointer
dereference.

Switch to devm_rtc_allocate_device/rtc_register_device to allocate the rtc
before requesting the IRQ.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-11-20 17:59:51 +01:00
Alexandre Belloni
9a7a548740 rtc: mt6397: fix possible race condition
[ Upstream commit babab2f86440352d24e76118fdd7d40cab5fd7bf ]

The IRQ is requested before the struct rtc is allocated and registered, but
this struct is used in the IRQ handler. This may lead to a NULL pointer
dereference.

Switch to devm_rtc_allocate_device/rtc_register_device to allocate the rtc
before requesting the IRQ.

Acked-by: Eddie Huang <eddie.huang@mediatek.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-11-20 17:59:51 +01:00
Alexandre Belloni
66130c3f37 rtc: rv8803: fix the rv8803 id in the OF table
[ Upstream commit c856618d20662695fcdb47bf4d560dc457662aec ]

The ID for RV8803 must be rv_8803

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-11-20 17:59:39 +01:00
Sam Ravnborg
9375241055 rtc: pcf8523: set xtal load capacitance from DT
[ Upstream commit 189927e719e36ceefbb8037f23d3849e47833aef ]

Add support for specifying the xtal load capacitance in the DT node.
The pcf8523 supports xtal load capacitance of 7pF or 12.5pF.
If the rtc has the wrong configuration the time will
drift several hours/week.

The driver use the default value 12.5pF.

The DT may specify either 7000fF or 12500fF.
(The DT uses femto Farad to avoid decimal numbers).
Other values are warned and the driver uses the default value.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-11-06 12:42:56 +01:00
Anson Huang
dc93018d45 rtc: snvs: fix possible race condition
[ Upstream commit 6fd4fe9b496d9ba3382992ff4fde3871d1b6f63d ]

The RTC IRQ is requested before the struct rtc_device is allocated,
this may lead to a NULL pointer dereference in IRQ handler.

To fix this issue, allocating the rtc_device struct before requesting
the RTC IRQ using devm_rtc_allocate_device, and use rtc_register_device
to register the RTC device.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Reviewed-by: Dong Aisheng <aisheng.dong@nxp.com>
Link: https://lore.kernel.org/r/20190716071858.36750-1-Anson.Huang@nxp.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-10-07 18:55:10 +02:00
Baruch Siach
3177ab541b rtc: pcf8523: don't return invalid date when battery is low
commit ecb4a353d3afd45b9bb30c85d03ee113a0589079 upstream.

The RTC_VL_READ ioctl reports the low battery condition. Still,
pcf8523_rtc_read_time() happily returns invalid dates in this case.
Check the battery health on pcf8523_rtc_read_time() to avoid that.

Reported-by: Erik Čuk <erik.cuk@domel.com>
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 08:21:00 +02:00
Alexandre Belloni
ae087a4a56 rtc: xgene: fix possible race condition
[ Upstream commit a652e00ee1233e251a337c28e18a1da59224e5ce ]

The IRQ is requested before the struct rtc is allocated and registered, but
this struct is used in the IRQ handler. This may lead to a NULL pointer
dereference.

Switch to devm_rtc_allocate_device/rtc_register_device to allocate the rtc
struct before requesting the IRQ.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-31 06:47:30 -07:00
Sven Van Asbroeck
b89551f459 rtc: 88pm860x: prevent use-after-free on device remove
[ Upstream commit f22b1ba15ee5785aa028384ebf77dd39e8e47b70 ]

The device's remove() attempts to shut down the delayed_work scheduled
on the kernel-global workqueue by calling flush_scheduled_work().

Unfortunately, flush_scheduled_work() does not prevent the delayed_work
from re-scheduling itself. The delayed_work might run after the device
has been removed, and touch the already de-allocated info structure.
This is a potential use-after-free.

Fix by calling cancel_delayed_work_sync() during remove(): this ensures
that the delayed work is properly cancelled, is no longer running, and
is not able to re-schedule itself.

This issue was detected with the help of Coccinelle.

Signed-off-by: Sven Van Asbroeck <TheSven73@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-31 06:47:21 -07:00
Alexandre Belloni
8217b8ee7b rtc: da9063: set uie_unsupported when relevant
[ Upstream commit 882c5e552ffd06856de42261460f46e18319d259 ]

The DA9063AD doesn't support alarms on any seconds and its granularity is
the minute. Set uie_unsupported in that case.

Reported-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reported-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Steve Twiss <stwiss.opensource@diasemi.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-08 07:20:49 +02:00
Geert Uytterhoeven
94cee4ed4c rtc: sh: Fix invalid alarm warning for non-enabled alarm
[ Upstream commit 15d82d22498784966df8e4696174a16b02cc1052 ]

When no alarm has been programmed on RSK-RZA1, an error message is
printed during boot:

    rtc rtc0: invalid alarm value: 2019-03-14T255:255:255

sh_rtc_read_alarm_value() returns 0xff when querying a hardware alarm
field that is not enabled.  __rtc_read_alarm() validates the received
alarm values, and fills in missing fields when needed.
While 0xff is handled fine for the year, month, and day fields, and
corrected as considered being out-of-range, this is not the case for the
hour, minute, and second fields, where -1 is expected for missing
fields.

Fix this by returning -1 instead, as this value is handled fine for all
fields.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-08 07:20:47 +02:00
Baolin Wang
c492471db9 rtc: Fix overflow when converting time64_t to rtc_time
commit 36d46cdb43efea74043e29e2a62b13e9aca31452 upstream.

If we convert one large time values to rtc_time, in the original formula
'days * 86400' can be overflowed in 'unsigned int' type to make the formula
get one incorrect remain seconds value. Thus we can use div_s64_rem()
function to avoid this situation.

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-27 14:13:55 +09:00
Maciej W. Rozycki
3f23e65d32 rtc: m41t80: Correct alarm month range with RTC reads
commit 3cc9ffbb1f51eb4320575a48e4805a8f52e0e26b upstream.

Add the missing adjustment of the month range on alarm reads from the
RTC, correcting an issue coming from commit 9c6dfed92c3e ("rtc: m41t80:
add alarm functionality").  The range is 1-12 for hardware and 0-11 for
`struct rtc_time', and is already correctly handled on alarm writes to
the RTC.

It was correct up until commit 48e9766726eb ("drivers/rtc/rtc-m41t80.c:
remove disabled alarm functionality") too, which removed the previous
implementation of alarm support.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Fixes: 9c6dfed92c3e ("rtc: m41t80: add alarm functionality")
References: 48e9766726eb ("drivers/rtc/rtc-m41t80.c: remove disabled alarm functionality")
Cc: stable@vger.kernel.org # 4.7+
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-09 17:14:52 +01:00
Trent Piepho
f1e1eb5c90 rtc: snvs: Add timeouts to avoid kernel lockups
[ Upstream commit cd7f3a249dbed2858e6c2f30e5be7f1f7a709ee2 ]

In order to read correctly from asynchronously updated RTC registers,
it's necessary to read repeatedly until their values do not change from
read to read.  It's also necessary to wait for three RTC clock ticks for
certain operations.  There are no timeouts in this code and these
operations could possibly loop forever.

To avoid kernel hangs, put in timeouts.

The iMX7d can be configured to stop the SRTC on a tamper event, which
will lockup the kernel inside this driver as described above.

These hangs can happen when running under qemu, which doesn't emulate
the SNVS RTC, though currently the driver will refuse to load on qemu
due to a timeout in the driver probe method.

It could also happen if the SRTC block where somehow placed into reset
or the slow speed clock that drives the SRTC counter (but not the CPU)
were to stop.

The symptoms on a two core iMX7d are a work queue hang on
rtc_timer_do_work(), which eventually blocks a systemd fsnotify
operation that triggers a work queue flush, causing systemd to hang and
thus causing all services that should be started by systemd, like a
console getty, to fail to start or stop.

Also optimize the wait code to wait less.  It only needs to wait for the
clock to advance three ticks, not to see it change three times.

Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Fabio Estevam <fabio.estevam@nxp.com>
Cc: Shawn Guo <shawn.guo@linaro.org>
Cc: Bryan O'Donoghue <pure.logic@nexus-software.ie>
Signed-off-by: Trent Piepho <tpiepho@impinj.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-12-21 14:13:18 +01:00
Hans de Goede
aa17c9c00c iio/hid-sensors: Fix IIO_CHAN_INFO_RAW returning wrong values for signed numbers
[ Upstream commit 0145b50566e7de5637e80ecba96c7f0e6fff1aad ]

Before this commit sensor_hub_input_attr_get_raw_value() failed to take
the signedness of 16 and 8 bit values into account, returning e.g.
65436 instead of -100 for the z-axis reading of an accelerometer.

This commit adds a new is_signed parameter to the function and makes all
callers pass the appropriate value for this.

While at it, this commit also fixes up some neighboring lines where
statements were needlessly split over 2 lines to improve readability.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-12-17 09:28:49 +01:00
Alexandre Belloni
7eebc934f3 rtc: omap: fix error path when pinctrl_register fails
commit 26e480f7bb7840fc0daa9c3af7c4501b2cf5902f upstream.

If pinctrl_register() fails probe will return with an error without locking
the RTC and disabling pm_runtime.
Set ret and jump to err instead.

Fixes: 97ea1906b3c2 ("rtc: omap: Support ext_wakeup configuration")
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-01 09:42:58 +01:00
Xulin Sun
6e4fbdc7a3 rtc: pcf2127: fix a kmemleak caused in pcf2127_i2c_gather_write
[ Upstream commit 9bde0afb7a906f1dabdba37162551565740b862d ]

pcf2127_i2c_gather_write() allocates memory as local variable
for i2c_master_send(), after finishing the master transfer,
the allocated memory should be freed. The kmemleak is reported:

unreferenced object 0xffff80231e7dba80 (size 64):
  comm "hwclock", pid 27762, jiffies 4296880075 (age 356.944s)
  hex dump (first 32 bytes):
    03 00 12 03 19 02 11 13 00 80 98 18 00 00 ff ff ................
    00 50 00 00 00 00 00 00 02 00 00 00 00 00 00 00 .P..............
  backtrace:
    [<ffff000008221398>] create_object+0xf8/0x278
    [<ffff000008a96264>] kmemleak_alloc+0x74/0xa0
    [<ffff00000821070c>] __kmalloc+0x1ac/0x348
    [<ffff0000087ed1dc>] pcf2127_i2c_gather_write+0x54/0xf8
    [<ffff0000085fd9d4>] _regmap_raw_write+0x464/0x850
    [<ffff0000085fe3f4>] regmap_bulk_write+0x1a4/0x348
    [<ffff0000087ed32c>] pcf2127_rtc_set_time+0xac/0xe8
    [<ffff0000087eaad8>] rtc_set_time+0x80/0x138
    [<ffff0000087ebfb0>] rtc_dev_ioctl+0x398/0x610
    [<ffff00000823f2c0>] do_vfs_ioctl+0xb0/0x848
    [<ffff00000823fae4>] SyS_ioctl+0x8c/0xa8
    [<ffff000008083ac0>] el0_svc_naked+0x34/0x38
    [<ffffffffffffffff>] 0xffffffffffffffff

Signed-off-by: Xulin Sun <xulin.sun@windriver.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-12-01 09:42:53 +01:00
Maciej W. Rozycki
677f423c99 rtc: hctosys: Add missing range error reporting
commit 7ce9a992ffde8ce93d5ae5767362a5c7389ae895 upstream.

Fix an issue with the 32-bit range error path in `rtc_hctosys' where no
error code is set and consequently the successful preceding call result
from `rtc_read_time' is propagated to `rtc_hctosys_ret'.  This in turn
makes any subsequent call to `hctosys_show' incorrectly report in sysfs
that the system time has been set from this RTC while it has not.

Set the error to ERANGE then if we can't express the result due to an
overflow.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Fixes: b3a5ac42ab18 ("rtc: hctosys: Ensure system time doesn't overflow time_t")
Cc: stable@vger.kernel.org # 4.17+
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-21 09:24:14 +01:00
Zhouyang Jia
8be9576222 rtc: bq4802: add error handling for devm_ioremap
[ Upstream commit 7874b919866ba91bac253fa219d3d4c82bb944df ]

When devm_ioremap fails, the lack of error-handling code may
cause unexpected results.

This patch adds error-handling code after calling devm_ioremap.

Signed-off-by: Zhouyang Jia <jiazhouyang09@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-26 08:38:13 +02:00
Johan Hovold
2b4c940dcc rtc: omap: fix potential crash on power off
commit 5c8b84f410b3819d14cb1ebf32e4b3714b5a6e0b upstream.

Do not set the system power-off callback and omap power-off rtc pointer
until we're done setting up our device to avoid leaving stale pointers
around after a late probe error.

Fixes: 97ea1906b3c2 ("rtc: omap: Support ext_wakeup configuration")
Cc: stable <stable@vger.kernel.org>     # 4.9
Cc: Marcin Niestroj <m.niestroj@grinn-global.com>
Cc: Tony Lindgren <tony@atomide.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Marcin Niestroj <m.niestroj@grinn-global.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-09 19:55:57 +02:00
Alexandre Belloni
9f25b54873 rtc: tps65910: fix possible race condition
[ Upstream commit e6000a438e534ee0afd9e83b67f4e23a26dd1067 ]

The IRQ is requested before the struct rtc is allocated and registered, but
this struct is used in the IRQ handler. This may lead to a NULL pointer
dereference.

Switch to devm_rtc_allocate_device/rtc_register_device to allocate the rtc
before requesting the IRQ.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-03 07:50:32 +02:00
Alexandre Belloni
8f5e7596fe rtc: vr41xx: fix possible race condition
[ Upstream commit 9a99247c9c1d1c95c6e8153d013979aac6111c6e ]

The probe function is not allowed to fail after the RTC is registered
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* */

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-03 07:50:32 +02:00
Alexandre Belloni
aca6728fa1 rtc: tps6586x: fix possible race condition
[ Upstream commit 63d22063073b0ab46d1e06fe633fb5de8f5c58e1 ]

The probe function is not allowed to fail after the RTC is registered
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* */

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-03 07:50:32 +02:00
Alexandre Belloni
6a929b97b7 rtc: ensure rtc_set_alarm fails when alarms are not supported
[ Upstream commit abfdff44bc38e9e2ef7929f633fb8462632299d4 ]

When using RTC_ALM_SET or RTC_WKALM_SET with rtc_wkalrm.enabled not set,
rtc_timer_enqueue() is not called and rtc_set_alarm() may succeed but the
subsequent RTC_AIE_ON ioctl will fail. RTC_ALM_READ would also fail in that
case.

Ensure rtc_set_alarm() fails when alarms are not supported to avoid letting
programs think the alarms are working for a particular RTC when they are
not.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-03 07:50:23 +02:00
Michael Trimarchi
88896a963b rtc: sun6i: Fix bit_idx value for clk_register_gate
commit 09018d4bd7994c2c9f775029bc24589bc85f76fa upstream.

clk-gate core will take bit_idx through clk_register_gate
and then do clk_gate_ops by using BIT(bit_idx), but rtc-sun6i
is passing bit_idx as BIT(bit_idx) it becomes BIT(BIT(bit_idx)
which is wrong and eventually external gate clock is not enabling.

This patch fixed by passing bit index and the original change
introduced from below commit.
"rtc: sun6i: Add support for the external oscillator gate"
(sha1: 	17ecd246414b3a0fe0cb248c86977a8bda465b7b)

Signed-off-by: Michael Trimarchi <michael@amarulasolutions.com>
Fixes: 17ecd246414b ("rtc: sun6i: Add support for the external oscillator gate")
Cc: stable@vger.kernel.org
Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-03 11:24:59 +02:00
James Hogan
6b73dfbd3c rtc: goldfish: Add missing MODULE_LICENSE
[ Upstream commit 82d632b85eb89f97051530f556cb49ee1c04bde7 ]

Fix the following warning in MIPS allmodconfig by adding a
MODULE_LICENSE() at the end of rtc-goldfish.c, based on the file header
comment which says GNU General Public License version 2:

WARNING: modpost: missing MODULE_LICENSE() in drivers/rtc/rtc-goldfish.o

Fixes: f22d9cdcb5eb ("rtc: goldfish: Add RTC driver for Android emulator")
Signed-off-by: James Hogan <jhogan@kernel.org>
Cc: Miodrag Dinic <miodrag.dinic@mips.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: linux-rtc@vger.kernel.org
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-25 16:18:02 +02:00
Alexandre Belloni
6f34e43650 rtc: rp5c01: fix possible race condition
[ Upstream commit bcdd559268039d8340d38fa58668393596e29fdc ]

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>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-25 16:18:01 +02:00
Colin Ian King
78227b671e rtc: tx4939: avoid unintended sign extension on a 24 bit shift
[ Upstream commit 347876ad47b9923ce26e686173bbf46581802ffa ]

The shifting of buf[5] by 24 bits to the left will be promoted to
a 32 bit signed int and then sign-extended to an unsigned long. If
the top bit of buf[5] is set then all then all the upper bits sec
end up as also being set because of the sign-extension. Fix this by
casting buf[5] to an unsigned long before the shift.

Detected by CoverityScan, CID#1465292 ("Unintended sign extension")

Fixes: 0e1492330cd2 ("rtc: add rtc-tx4939 driver")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-25 16:18:01 +02:00
Alexandre Belloni
459aa4904a rtc: m41t80: fix race conditions
[ Upstream commit 10d0c768cc6d581523d673b9d1b54213f8a5eb24 ]

The IRQ is requested before the struct rtc is allocated and registered, but
this struct is used in the IRQ handler, leading to:

Unable to handle kernel NULL pointer dereference at virtual address 0000017c
pgd = a38a2f9b
[0000017c] *pgd=00000000
Internal error: Oops: 5 [#1] ARM
Modules linked in:
CPU: 0 PID: 613 Comm: irq/48-m41t80 Not tainted 4.16.0-rc1+ #42
Hardware name: Atmel SAMA5
PC is at mutex_lock+0x14/0x38
LR is at m41t80_handle_irq+0x1c/0x9c
pc : [<c06e864c>]    lr : [<c04b70f0>]    psr: 20000013
sp : dec73f30  ip : 00000000  fp : dec56d98
r10: df437cf0  r9 : c0a03008  r8 : c0145ffc
r7 : df5c4300  r6 : dec568d0  r5 : df593000  r4 : 0000017c
r3 : df592800  r2 : 60000013  r1 : df593000  r0 : 0000017c
Flags: nzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
Control: 10c53c7d  Table: 20004059  DAC: 00000051
Process irq/48-m41t80 (pid: 613, stack limit = 0xb52d091e)
Stack: (0xdec73f30 to 0xdec74000)
3f20:                                     dec56840 df5c4300 00000001 df5c4300
3f40: c0145ffc c0146018 dec56840 ffffe000 00000001 c0146290 dec567c0 00000000
3f60: c0146084 ed7c9a62 c014615c dec56d80 dec567c0 00000000 dec72000 dec56840
3f80: c014615c c012ffc0 dec72000 dec567c0 c012fe80 00000000 00000000 00000000
3fa0: 00000000 00000000 00000000 c01010e8 00000000 00000000 00000000 00000000
3fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
3fe0: 00000000 00000000 00000000 00000000 00000013 00000000 29282726 2d2c2b2a
[<c06e864c>] (mutex_lock) from [<c04b70f0>] (m41t80_handle_irq+0x1c/0x9c)
[<c04b70f0>] (m41t80_handle_irq) from [<c0146018>] (irq_thread_fn+0x1c/0x54)
[<c0146018>] (irq_thread_fn) from [<c0146290>] (irq_thread+0x134/0x1c0)
[<c0146290>] (irq_thread) from [<c012ffc0>] (kthread+0x140/0x148)
[<c012ffc0>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
Exception stack(0xdec73fb0 to 0xdec73ff8)
3fa0:                                     00000000 00000000 00000000 00000000
3fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
3fe0: 00000000 00000000 00000000 00000000 00000013 00000000
Code: e3c33d7f e3c3303f f5d0f000 e593300c (e1901f9f)
---[ end trace 22b027302eb7c604 ]---
genirq: exiting task "irq/48-m41t80" (613) is an active IRQ thread (irq 48)

Also, there is another possible race condition. The probe function is not
allowed to fail after the RTC is registered 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 allocate the rtc
before requesting the IRQ and register it as late as possible.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-25 16:18:01 +02:00
Alexandre Belloni
6266010c38 rtc: rk808: fix possible race condition
[ Upstream commit 201fac95e799c3d0304ec724d555e1251b9f6e84 ]

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>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-25 16:18:01 +02:00
Alexandre Belloni
6c1c171164 rtc: hctosys: Ensure system time doesn't overflow time_t
[ Upstream commit b3a5ac42ab18b7d1a8f2f072ca0ee76a3b754a43 ]

On 32bit platforms, time_t is still a signed 32bit long. If it is
overflowed, userspace and the kernel cant agree on the current system time.
This causes multiple issues, in particular with systemd:
https://github.com/systemd/systemd/issues/1143

A good workaround is to simply avoid using hctosys which is something I
greatly encourage as the time is better set by userspace.

However, many distribution enable it and use systemd which is rendering the
system unusable in case the RTC holds a date after 2038 (and more so after
2106). Many drivers have workaround for this case and they should be
eliminated so there is only one place left to fix when userspace is able to
cope with dates after the 31bit overflow.

Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-25 16:18:00 +02:00
Bryan O'Donoghue
731d965a58 rtc: snvs: Fix usage of snvs_rtc_enable
[ Upstream commit 1485991c024603b2fb4ae77beb7a0d741128a48e ]

commit 179a502f8c46 ("rtc: snvs: add Freescale rtc-snvs driver") introduces
the SNVS RTC driver with a function snvs_rtc_enable().

snvs_rtc_enable() can return an error on the enable path however this
driver does not currently trap that failure on the probe() path and
consequently if enabling the RTC fails we encounter a later error spinning
forever in rtc_write_sync_lp().

[   36.093481] [<c010d630>] (__irq_svc) from [<c0c2e9ec>] (_raw_spin_unlock_irqrestore+0x34/0x44)
[   36.102122] [<c0c2e9ec>] (_raw_spin_unlock_irqrestore) from [<c072e32c>] (regmap_read+0x4c/0x5c)
[   36.110938] [<c072e32c>] (regmap_read) from [<c085d0f4>] (rtc_write_sync_lp+0x6c/0x98)
[   36.118881] [<c085d0f4>] (rtc_write_sync_lp) from [<c085d160>] (snvs_rtc_alarm_irq_enable+0x40/0x4c)
[   36.128041] [<c085d160>] (snvs_rtc_alarm_irq_enable) from [<c08567b4>] (rtc_timer_do_work+0xd8/0x1a8)
[   36.137291] [<c08567b4>] (rtc_timer_do_work) from [<c01441b8>] (process_one_work+0x28c/0x76c)
[   36.145840] [<c01441b8>] (process_one_work) from [<c01446cc>] (worker_thread+0x34/0x58c)
[   36.153961] [<c01446cc>] (worker_thread) from [<c014aee4>] (kthread+0x138/0x150)
[   36.161388] [<c014aee4>] (kthread) from [<c0107e14>] (ret_from_fork+0x14/0x20)
[   36.168635] rcu_sched kthread starved for 2602 jiffies! g496 c495 f0x2 RCU_GP_WAIT_FQS(3) ->state=0x0 ->cpu=0
[   36.178564] rcu_sched       R  running task        0     8      2 0x00000000
[   36.185664] [<c0c288b0>] (__schedule) from [<c0c29134>] (schedule+0x3c/0xa0)
[   36.192739] [<c0c29134>] (schedule) from [<c0c2db80>] (schedule_timeout+0x78/0x4e0)
[   36.200422] [<c0c2db80>] (schedule_timeout) from [<c01a7ab0>] (rcu_gp_kthread+0x648/0x1864)
[   36.208800] [<c01a7ab0>] (rcu_gp_kthread) from [<c014aee4>] (kthread+0x138/0x150)
[   36.216309] [<c014aee4>] (kthread) from [<c0107e14>] (ret_from_fork+0x14/0x20)

This patch fixes by parsing the result of rtc_write_sync_lp() and
propagating both in the probe and elsewhere. If the RTC doesn't start we
don't proceed loading the driver and don't get into this loop mess later
on.

Fixes: 179a502f8c46 ("rtc: snvs: add Freescale rtc-snvs driver")
Signed-off-by: Bryan O'Donoghue <pure.logic@nexus-software.ie>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-25 16:18:00 +02:00
Nicholas Piggin
79340bda01 rtc: opal: Fix OPAL RTC driver OPAL_BUSY loops
commit 682e6b4da5cbe8e9a53f979a58c2a9d7dc997175 upstream.

The OPAL RTC driver does not sleep in case it gets OPAL_BUSY or
OPAL_BUSY_EVENT from firmware, which causes large scheduling
latencies, up to 50 seconds have been observed here when RTC stops
responding (BMC reboot can do it).

Fix this by converting it to the standard form OPAL_BUSY loop that
sleeps.

Fixes: 628daa8d5abf ("powerpc/powernv: Add RTC and NVRAM support plus RTAS fallbacks")
Cc: stable@vger.kernel.org # v3.2+
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-01 12:58:24 -07:00
Jerome Brunet
e6bc3a4b0c clk: divider: fix incorrect usage of container_of
[ Upstream commit 12a26c298d2a8b1cab498533fa65198e49e3afd3 ]

divider_recalc_rate() is an helper function used by clock divider of
different types, so the structure containing the 'hw' pointer is not
always a 'struct clk_divider'

At the following line:
> div = _get_div(table, val, flags, divider->width);

in several cases, the value of 'divider->width' is garbage as the actual
structure behind this memory is not a 'struct clk_divider'

Fortunately, this width value is used by _get_val() only when
CLK_DIVIDER_MAX_AT_ZERO flag is set. This has never been the case so
far when the structure is not a 'struct clk_divider'. This is probably
why we did not notice this bug before

Fixes: afe76c8fd030 ("clk: allow a clk divider with max divisor when zero")
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Sylvain Lemieux <slemieux.tyco@gmail.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-12 12:32:13 +02:00
Alexandre Belloni
9766562956 rtc: ac100: Fix multiple race conditions
[ Upstream commit 994ec64c0a193940be7a6fd074668b9446d3b6c3 ]

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* */

Also, the interrupt handler: ac100_rtc_irq() is dereferencing chip->rtc but
this may still be NULL when it is called, resulting in:
Unable to handle kernel NULL pointer dereference at virtual address 00000194
pgd = (ptrval)
[00000194] *pgd=00000000
Internal error: Oops: 5 [#1] SMP ARM
Modules linked in:
CPU: 0 PID: 72 Comm: irq/71-ac100-rt Not tainted 4.15.0-rc1-next-20171201-dirty #120
Hardware name: Allwinner sun8i Family
task: (ptrval) task.stack: (ptrval)
PC is at mutex_lock+0x14/0x3c
LR is at ac100_rtc_irq+0x38/0xc8
pc : [<c06543a4>]    lr : [<c04d9a2c>]    psr: 60000053
sp : ee9c9f28  ip : 00000000  fp : ee9adfdc
r10: 00000000  r9 : c0a04c48  r8 : c015ed18
r7 : ee9bd600  r6 : ee9c9f28  r5 : ee9af590  r4 : c0a04c48
r3 : ef3cb3c0  r2 : 00000000  r1 : ee9af590  r0 : 00000194
Flags: nZCv  IRQs on  FIQs off  Mode SVC_32  ISA ARM  Segment none
Control: 10c5387d  Table: 4000406a  DAC: 00000051
Process irq/71-ac100-rt (pid: 72, stack limit = 0x(ptrval))
Stack: (0xee9c9f28 to 0xee9ca000)
9f20:                   00000000 7c2fd1be c015ed18 ee9adf40 ee9c0400 ee9c0400
9f40: ee9adf40 c015ed34 ee9c8000 ee9adf64 ee9c0400 c015f040 ee9adf80 00000000
9f60: c015ee24 7c2fd1be ee9adfc0 ee9adf80 00000000 ee9c8000 ee9adf40 c015eef4
9f80: ef1eba34 c0138f14 ee9c8000 ee9adf80 c0138df4 00000000 00000000 00000000
9fa0: 00000000 00000000 00000000 c01010e8 00000000 00000000 00000000 00000000
9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
9fe0: 00000000 00000000 00000000 00000000 00000013 00000000 ffffffff ffffffff
[<c06543a4>] (mutex_lock) from [<c04d9a2c>] (ac100_rtc_irq+0x38/0xc8)
[<c04d9a2c>] (ac100_rtc_irq) from [<c015ed34>] (irq_thread_fn+0x1c/0x54)
[<c015ed34>] (irq_thread_fn) from [<c015f040>] (irq_thread+0x14c/0x214)
[<c015f040>] (irq_thread) from [<c0138f14>] (kthread+0x120/0x150)
[<c0138f14>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)

Solve both issues by moving to
devm_rtc_allocate_device()/rtc_register_device()

Reported-by: Quentin Schulz <quentin.schulz@free-electrons.com>
Tested-by: Quentin Schulz <quentin.schulz@free-electrons.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-24 11:01:24 +01:00
Alexey Khoroshilov
f113f79441 rtc: brcmstb-waketimer: fix error handling in brcmstb_waketmr_probe()
[ Upstream commit f2eef045de9defbc6fc6b72b17f0941cbe26c81d ]

brcmstb_waketmr_probe() does not disable timer->clk on error paths.

Found by Linux Driver Verification project (linuxtesting.org).

Fixes: c4f07ecee22e ("rtc: brcmstb-waketimer: Add Broadcom STB wake-timer")
Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-19 08:42:49 +01:00
Stewart Smith
c3bdd54704 rtc-opal: Fix handling of firmware error codes, prevent busy loops
commit 5b8b58063029f02da573120ef4dc9079822e3cda upstream.

According to the OPAL docs:
  skiboot-5.2.5/doc/opal-api/opal-rtc-read-3.txt
  skiboot-5.2.5/doc/opal-api/opal-rtc-write-4.txt

OPAL_HARDWARE may be returned from OPAL_RTC_READ or OPAL_RTC_WRITE and
this indicates either a transient or permanent error.

Prior to this patch, Linux was not dealing with OPAL_HARDWARE being a
permanent error particularly well, in that you could end up in a busy
loop.

This was not too hard to trigger on an AMI BMC based OpenPOWER machine
doing a continuous "ipmitool mc reset cold" to the BMC, the result of
that being that we'd get stuck in an infinite loop in
opal_get_rtc_time().

We now retry a few times before returning the error higher up the
stack.

Fixes: 16b1d26e77b1 ("rtc/tpo: Driver to support rtc and wakeup on PowerNV platform")
Cc: stable@vger.kernel.org # v3.19+
Signed-off-by: Stewart Smith <stewart@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-22 15:42:25 +01:00