<feed xmlns='http://www.w3.org/2005/Atom'>
<title>user/sven/linux.git/drivers/rtc, branch v5.15.57</title>
<subtitle>Linux Kernel
</subtitle>
<id>https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v5.15.57</id>
<link rel='self' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v5.15.57'/>
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<updated>2022-06-14T16:36:07Z</updated>
<entry>
<title>rtc: ftrtc010: Fix error handling in ftrtc010_rtc_probe</title>
<updated>2022-06-14T16:36:07Z</updated>
<author>
<name>Miaoqian Lin</name>
<email>linmq006@gmail.com</email>
</author>
<published>2022-04-03T05:49:12Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=e1928887219b09140c043eed13fbd30bf22bd68e'/>
<id>urn:sha1:e1928887219b09140c043eed13fbd30bf22bd68e</id>
<content type='text'>
[ Upstream commit b520cbe5be37b1b9b401c0b6ecbdae32575273db ]

In the error handling path, the clk_prepare_enable() function
call should be balanced by a corresponding 'clk_disable_unprepare()'
call , as already done in the remove function.

clk_disable_unprepare calls clk_disable() and clk_unprepare().
They will use IS_ERR_OR_NULL to check the argument.

Fixes: ac05fba39cc5 ("rtc: gemini: Add optional clock handling")
Signed-off-by: Miaoqian Lin &lt;linmq006@gmail.com&gt;
Reviewed-by: Linus Walleij &lt;linus.walleij@linaro.org&gt;
Signed-off-by: Alexandre Belloni &lt;alexandre.belloni@bootlin.com&gt;
Link: https://lore.kernel.org/r/20220403054912.31739-1-linmq006@gmail.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>rtc: ftrtc010: Use platform_get_irq() to get the interrupt</title>
<updated>2022-06-14T16:36:07Z</updated>
<author>
<name>Lad Prabhakar</name>
<email>prabhakar.mahadev-lad.rj@bp.renesas.com</email>
</author>
<published>2021-12-20T01:15:24Z</published>
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<id>urn:sha1:49f698e2205299224dbf4599e87ca1b1d78683c3</id>
<content type='text'>
[ Upstream commit 05020a733b02cf7a474305e620fb306cd3abfe84 ]

platform_get_resource(pdev, IORESOURCE_IRQ, ..) relies on static
allocation of IRQ resources in DT core code, this causes an issue
when using hierarchical interrupt domains using "interrupts" property
in the node as this bypasses the hierarchical setup and messes up the
irq chaining.

In preparation for removal of static setup of IRQ resource from DT core
code use platform_get_irq().

Signed-off-by: Lad Prabhakar &lt;prabhakar.mahadev-lad.rj@bp.renesas.com&gt;
Reviewed-by: Linus Walleij &lt;linus.walleij@linaro.org&gt;
Signed-off-by: Alexandre Belloni &lt;alexandre.belloni@bootlin.com&gt;
Link: https://lore.kernel.org/r/20211220011524.17206-1-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>rtc: mt6397: check return value after calling platform_get_resource()</title>
<updated>2022-06-14T16:36:07Z</updated>
<author>
<name>Yang Yingliang</name>
<email>yangyingliang@huawei.com</email>
</author>
<published>2022-05-05T12:50:43Z</published>
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<id>urn:sha1:865051de2d9eaa50630e055b73921ceaf3c4a7fc</id>
<content type='text'>
[ Upstream commit d3b43eb505bffb8e4cdf6800c15660c001553fe6 ]

It will cause null-ptr-deref if platform_get_resource() returns NULL,
we need check the return value.

Fixes: fc2979118f3f ("rtc: mediatek: Add MT6397 RTC driver")
Signed-off-by: Yang Yingliang &lt;yangyingliang@huawei.com&gt;
Reviewed-by: AngeloGioacchino Del Regno &lt;angelogioacchino.delregno@collabora.com&gt;
Signed-off-by: Alexandre Belloni &lt;alexandre.belloni@bootlin.com&gt;
Link: https://lore.kernel.org/r/20220505125043.1594771-1-yangyingliang@huawei.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>rtc: mc146818-lib: Fix the AltCentury for AMD platforms</title>
<updated>2022-05-25T07:57:26Z</updated>
<author>
<name>Mario Limonciello</name>
<email>mario.limonciello@amd.com</email>
</author>
<published>2022-01-11T22:57:50Z</published>
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<id>urn:sha1:258a7a7fb568c4ae5c59a445f5ea0b7da35bb552</id>
<content type='text'>
[ Upstream commit 3ae8fd41573af4fb3a490c9ed947fc936ba87190 ]

Setting the century forward has been failing on AMD platforms.
There was a previous attempt at fixing this for family 0x17 as part of
commit 7ad295d5196a ("rtc: Fix the AltCentury value on AMD/Hygon
platform") but this was later reverted due to some problems reported
that appeared to stem from an FW bug on a family 0x17 desktop system.

The same comments mentioned in the previous commit continue to apply
to the newer platforms as well.

```
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.
```

However in closer examination the change previously submitted was also
modifying bits 5 &amp; 6 which are declared reserved in the AMD documentation.
So instead modify just the DV0 bank selection bit.

Being cognizant that there was a failure reported before, split the code
change out to a static function that can also be used for exclusions if
any regressions such as Mikhail's pop up again.

Cc: Jinke Fan &lt;fanjinke@hygon.cn&gt;
Cc: Mikhail Gavrilov &lt;mikhail.v.gavrilov@gmail.com&gt;
Link: https://lore.kernel.org/all/CABXGCsMLob0DC25JS8wwAYydnDoHBSoMh2_YLPfqm3TTvDE-Zw@mail.gmail.com/
Link: https://www.amd.com/system/files/TechDocs/51192_Bolton_FCH_RRG.pdf
Signed-off-by: Raul E Rangel &lt;rrangel@chromium.org&gt;
Signed-off-by: Mario Limonciello &lt;mario.limonciello@amd.com&gt;
Signed-off-by: Alexandre Belloni &lt;alexandre.belloni@bootlin.com&gt;
Link: https://lore.kernel.org/r/20220111225750.1699-1-mario.limonciello@amd.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>rtc: sun6i: Fix time overflow handling</title>
<updated>2022-05-25T07:57:24Z</updated>
<author>
<name>Andre Przywara</name>
<email>andre.przywara@arm.com</email>
</author>
<published>2022-02-11T12:26:28Z</published>
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<id>urn:sha1:0a482fc4290b297d5ffb855c11026aa0b69f0409</id>
<content type='text'>
[ Upstream commit 9f6cd82eca7e91a0d0311242a87c6aa3c2737968 ]

Using "unsigned long" for UNIX timestamps is never a good idea, and
comparing the value of such a variable against U32_MAX does not do
anything useful on 32-bit systems.

Use the proper time64_t type when dealing with timestamps, and avoid
cutting down the time range unnecessarily. This also fixes the flawed
check for the alarm time being too far into the future.

The check for this condition is actually somewhat theoretical, as the
RTC counts till 2033 only anyways, and 2^32 seconds from now is not
before the year 2157 - at which point I hope nobody will be using this
hardware anymore.

Signed-off-by: Andre Przywara &lt;andre.przywara@arm.com&gt;
Reviewed-by: Jernej Skrabec &lt;jernej.skrabec@gmail.com&gt;
Signed-off-by: Alexandre Belloni &lt;alexandre.belloni@bootlin.com&gt;
Link: https://lore.kernel.org/r/20220211122643.1343315-4-andre.przywara@arm.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>rtc: pcf2127: fix bug when reading alarm registers</title>
<updated>2022-05-25T07:57:23Z</updated>
<author>
<name>Hugo Villeneuve</name>
<email>hvilleneuve@dimonoff.com</email>
</author>
<published>2022-02-08T16:29:07Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=fe9f2f3a68fce6ab3fcedc3a316152061d0cd577'/>
<id>urn:sha1:fe9f2f3a68fce6ab3fcedc3a316152061d0cd577</id>
<content type='text'>
[ Upstream commit 73ce05302007eece23a6acb7dc124c92a2209087 ]

The first bug is that reading the 5 alarm registers results in a read
operation of 20 bytes. The reason is because the destination buffer is
defined as an array of "unsigned int", and we use the sizeof()
operator on this array to define the bulk read count.

The second bug is that the read value is invalid, because we are
indexing the destination buffer as integers (4 bytes), instead of
indexing it as u8.

Changing the destination buffer type to u8 fixes both problems.

Signed-off-by: Hugo Villeneuve &lt;hvilleneuve@dimonoff.com&gt;
Signed-off-by: Alexandre Belloni &lt;alexandre.belloni@bootlin.com&gt;
Link: https://lore.kernel.org/r/20220208162908.3182581-1-hugo@hugovil.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>rtc: fix use-after-free on device removal</title>
<updated>2022-05-25T07:57:23Z</updated>
<author>
<name>Vincent Whitchurch</name>
<email>vincent.whitchurch@axis.com</email>
</author>
<published>2021-12-10T16:09:51Z</published>
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<id>urn:sha1:25ddeb6be3d94a112958c000136751cbca57015b</id>
<content type='text'>
[ Upstream commit c8fa17d9f08a448184f03d352145099b5beb618e ]

If the irqwork is still scheduled or running while the RTC device is
removed, a use-after-free occurs in rtc_timer_do_work().  Cleanup the
timerqueue and ensure the work is stopped to fix this.

 BUG: KASAN: use-after-free in mutex_lock+0x94/0x110
 Write of size 8 at addr ffffff801d846338 by task kworker/3:1/41

 Workqueue: events rtc_timer_do_work
 Call trace:
  mutex_lock+0x94/0x110
  rtc_timer_do_work+0xec/0x630
  process_one_work+0x5fc/0x1344
  ...

 Allocated by task 551:
  kmem_cache_alloc_trace+0x384/0x6e0
  devm_rtc_allocate_device+0xf0/0x574
  devm_rtc_device_register+0x2c/0x12c
  ...

 Freed by task 572:
  kfree+0x114/0x4d0
  rtc_device_release+0x64/0x80
  device_release+0x8c/0x1f4
  kobject_put+0x1c4/0x4b0
  put_device+0x20/0x30
  devm_rtc_release_device+0x1c/0x30
  devm_action_release+0x54/0x90
  release_nodes+0x124/0x310
  devres_release_group+0x170/0x240
  i2c_device_remove+0xd8/0x314
  ...

 Last potentially related work creation:
  insert_work+0x5c/0x330
  queue_work_on+0xcc/0x154
  rtc_set_time+0x188/0x5bc
  rtc_dev_ioctl+0x2ac/0xbd0
  ...

Signed-off-by: Vincent Whitchurch &lt;vincent.whitchurch@axis.com&gt;
Signed-off-by: Alexandre Belloni &lt;alexandre.belloni@bootlin.com&gt;
Link: https://lore.kernel.org/r/20211210160951.7718-1-vincent.whitchurch@axis.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>rtc: mc146818-lib: fix signedness bug in mc146818_get_time()</title>
<updated>2022-04-13T18:59:26Z</updated>
<author>
<name>Dan Carpenter</name>
<email>dan.carpenter@oracle.com</email>
</author>
<published>2022-01-11T07:19:22Z</published>
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<id>urn:sha1:22174e8ce8ac32a841e5c63a8b75fdae85ffef8a</id>
<content type='text'>
commit 7372971c1be5b7d4fdd8ad237798bdc1d1d54162 upstream.

The mc146818_get_time() function returns zero on success or negative
a error code on failure.  It needs to be type int.

Fixes: d35786b3a28d ("rtc: mc146818-lib: change return values of mc146818_get_time()")
Signed-off-by: Dan Carpenter &lt;dan.carpenter@oracle.com&gt;
Reviewed-by: Mateusz Jończyk &lt;mat.jonczyk@o2.pl&gt;
Signed-off-by: Alexandre Belloni &lt;alexandre.belloni@bootlin.com&gt;
Link: https://lore.kernel.org/r/20220111071922.GE11243@kili
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>rtc: mc146818-lib: fix RTC presence check</title>
<updated>2022-04-13T18:59:14Z</updated>
<author>
<name>Mateusz Jończyk</name>
<email>mat.jonczyk@o2.pl</email>
</author>
<published>2021-12-10T20:01:26Z</published>
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<id>urn:sha1:985d87e6a36551b292443c52a4ae9b82296d1f51</id>
<content type='text'>
[ Upstream commit ea6fa4961aab8f90a8aa03575a98b4bda368d4b6 ]

To prevent an infinite loop in mc146818_get_time(),
commit 211e5db19d15 ("rtc: mc146818: Detect and handle broken RTCs")
added a check for RTC availability. Together with a later fix, it
checked if bit 6 in register 0x0d is cleared.

This, however, caused a false negative on a motherboard with an AMD
SB710 southbridge; according to the specification [1], bit 6 of register
0x0d of this chipset is a scratchbit. This caused a regression in Linux
5.11 - the RTC was determined broken by the kernel and not used by
rtc-cmos.c [3]. This problem was also reported in Fedora [4].

As a better alternative, check whether the UIP ("Update-in-progress")
bit is set for longer then 10ms. If that is the case, then apparently
the RTC is either absent (and all register reads return 0xff) or broken.
Also limit the number of loop iterations in mc146818_get_time() to 10 to
prevent an infinite loop there.

The functions mc146818_get_time() and mc146818_does_rtc_work() will be
refactored later in this patch series, in order to fix a separate
problem with reading / setting the RTC alarm time. This is done so to
avoid a confusion about what is being fixed when.

In a previous approach to this problem, I implemented a check whether
the RTC_HOURS register contains a value &lt;= 24. This, however, sometimes
did not work correctly on my Intel Kaby Lake laptop. According to
Intel's documentation [2], "the time and date RAM locations (0-9) are
disconnected from the external bus" during the update cycle so reading
this register without checking the UIP bit is incorrect.

[1] AMD SB700/710/750 Register Reference Guide, page 308,
https://developer.amd.com/wordpress/media/2012/10/43009_sb7xx_rrg_pub_1.00.pdf

[2] 7th Generation Intel ® Processor Family I/O for U/Y Platforms [...] Datasheet
Volume 1 of 2, page 209
Intel's Document Number: 334658-006,
https://www.intel.com/content/dam/www/public/us/en/documents/datasheets/7th-and-8th-gen-core-family-mobile-u-y-processor-lines-i-o-datasheet-vol-1.pdf

[3] Functions in arch/x86/kernel/rtc.c apparently were using it.

[4] https://bugzilla.redhat.com/show_bug.cgi?id=1936688

Fixes: 211e5db19d15 ("rtc: mc146818: Detect and handle broken RTCs")
Fixes: ebb22a059436 ("rtc: mc146818: Dont test for bit 0-5 in Register D")
Signed-off-by: Mateusz Jończyk &lt;mat.jonczyk@o2.pl&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Alessandro Zummo &lt;a.zummo@towertech.it&gt;
Cc: Alexandre Belloni &lt;alexandre.belloni@bootlin.com&gt;
Signed-off-by: Alexandre Belloni &lt;alexandre.belloni@bootlin.com&gt;
Link: https://lore.kernel.org/r/20211210200131.153887-5-mat.jonczyk@o2.pl
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>rtc: Check return value from mc146818_get_time()</title>
<updated>2022-04-13T18:59:14Z</updated>
<author>
<name>Mateusz Jończyk</name>
<email>mat.jonczyk@o2.pl</email>
</author>
<published>2021-12-10T20:01:25Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=be6c3152d6f6d9c4a72eeb7126b762b413b1030c'/>
<id>urn:sha1:be6c3152d6f6d9c4a72eeb7126b762b413b1030c</id>
<content type='text'>
[ Upstream commit 0dd8d6cb9eddfe637bcd821bbfd40ebd5a0737b9 ]

There are 4 users of mc146818_get_time() and none of them was checking
the return value from this function. Change this.

Print the appropriate warnings in callers of mc146818_get_time() instead
of in the function mc146818_get_time() itself, in order not to add
strings to rtc-mc146818-lib.c, which is kind of a library.

The callers of alpha_rtc_read_time() and cmos_read_time() may use the
contents of (struct rtc_time *) even when the functions return a failure
code. Therefore, set the contents of (struct rtc_time *) to 0x00,
which looks more sensible then 0xff and aligns with the (possibly
stale?) comment in cmos_read_time:

	/*
	 * If pm_trace abused the RTC for storage, set the timespec to 0,
	 * which tells the caller that this RTC value is unusable.
	 */

For consistency, do this in mc146818_get_time().

Note: hpet_rtc_interrupt() may call mc146818_get_time() many times a
second. It is very unlikely, though, that the RTC suddenly stops
working and mc146818_get_time() would consistently fail.

Only compile-tested on alpha.

Signed-off-by: Mateusz Jończyk &lt;mat.jonczyk@o2.pl&gt;
Cc: Richard Henderson &lt;rth@twiddle.net&gt;
Cc: Ivan Kokshaysky &lt;ink@jurassic.park.msu.ru&gt;
Cc: Matt Turner &lt;mattst88@gmail.com&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Dave Hansen &lt;dave.hansen@linux.intel.com&gt;
Cc: Alessandro Zummo &lt;a.zummo@towertech.it&gt;
Cc: Alexandre Belloni &lt;alexandre.belloni@bootlin.com&gt;
Cc: linux-alpha@vger.kernel.org
Cc: x86@kernel.org
Signed-off-by: Alexandre Belloni &lt;alexandre.belloni@bootlin.com&gt;
Link: https://lore.kernel.org/r/20211210200131.153887-4-mat.jonczyk@o2.pl
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
</feed>
