From: Igor Velkov <iav@iav.lv>
To: Neil Armstrong <neil.armstrong@linaro.org>
Cc: iav@iav.lv, John Stultz <jstultz@google.com>,
Thomas Gleixner <tglx@kernel.org>,
Alexandre Belloni <alexandre.belloni@bootlin.com>,
Rob Herring <robh@kernel.org>,
Krzysztof Kozlowski <krzk+dt@kernel.org>,
Conor Dooley <conor+dt@kernel.org>,
Kevin Hilman <khilman@baylibre.com>,
Stephen Boyd <sboyd@kernel.org>,
Miroslav Lichvar <mlichvar@redhat.com>,
Jerome Brunet <jbrunet@baylibre.com>,
Martin Blumenstingl <martin.blumenstingl@googlemail.com>,
linux-rtc@vger.kernel.org, devicetree@vger.kernel.org,
linux-arm-kernel@lists.infradead.org,
linux-amlogic@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH RFC 0/3] alarmtimer: Choose the wakeup RTC per sleep state from the device tree
Date: Wed, 04 Nov 2026 20:38:00 +0200 [thread overview]
Message-ID: <20261104-alarmtimer-rtc-neil-reply-1@iav.lv> (raw)
In-Reply-To: <399668f0-e97a-438e-b761-1ea6c18d904b@linaro.org>
On 11/4/26, Neil Armstrong wrote:
> This sounds bulky, perhaps it would be much simpler if we just added
> all the available RTCs which has RTC_FEATURE_ALARM and can wakeup ?
>
> Just switch from 1 single to multiple RTCs in a linked list and you're
> done, no DT & bindings changes.
A list it is, and v2 drops linux,alarmtimer-priority.
Arming every RTC makes the coarsest one fire first: pcf8563 has no
alarm seconds, so its alarm comes up to 59 s early, and an RTC with
alarm_offset_max wakes earlier still. The board wakes before the timer
expires, and the next alarm may come seconds later: while it is still
resuming, which takes seconds with disks and PCIe, or right after it
is suspended again. Drivers then go through suspend and resume at
short intervals. Arming one RTC per sleep state avoids that, and which
RTC wakes from which state is board knowledge, so v2 keeps
linux,wakeup-states.
--
Igor Velkov
_______________________________________________
linux-amlogic mailing list
linux-amlogic@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-amlogic
prev parent reply other threads:[~2026-11-04 18:38 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-11-04 5:54 Igor Velkov via B4 Relay
2026-11-04 5:54 ` [PATCH RFC 1/3] dt-bindings: rtc: Add linux,wakeup-states and linux,alarmtimer-priority Igor Velkov via B4 Relay
2026-11-04 6:06 ` sashiko-bot
2026-11-04 5:54 ` [PATCH RFC 2/3] alarmtimer: Choose the wakeup RTC by sleep state and priority Igor Velkov via B4 Relay
2026-11-04 5:54 ` [PATCH RFC 3/3] arm64: dts: amlogic: meson-sm1-odroid-hc4: Describe which RTC wakes the board Igor Velkov via B4 Relay
2026-11-04 8:50 ` [PATCH RFC 0/3] alarmtimer: Choose the wakeup RTC per sleep state from the device tree Neil Armstrong
2026-11-04 18:38 ` Igor Velkov [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20261104-alarmtimer-rtc-neil-reply-1@iav.lv \
--to=iav@iav.lv \
--cc=alexandre.belloni@bootlin.com \
--cc=conor+dt@kernel.org \
--cc=devicetree@vger.kernel.org \
--cc=jbrunet@baylibre.com \
--cc=jstultz@google.com \
--cc=khilman@baylibre.com \
--cc=krzk+dt@kernel.org \
--cc=linux-amlogic@lists.infradead.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-rtc@vger.kernel.org \
--cc=martin.blumenstingl@googlemail.com \
--cc=mlichvar@redhat.com \
--cc=neil.armstrong@linaro.org \
--cc=robh@kernel.org \
--cc=sboyd@kernel.org \
--cc=tglx@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®