Fan toggles on/off repeatedly

[Juerg Haefliger]

[Impact]

Fan toggles on/off if temp is around trip temp.

[Fix]

https://github.com/raspberrypi/linux/commit/d3668f4e7e2747f38d7f680df231f02dd33d3a13

[Test Case]

Observe fan behavior when temp crosses the trip temp (in both directions). Hysteresis should prevent rapid on/off toggling.

[Where Problems Could Occur]

Fan on Pi might misbehave (stuck on or off or toggling).

[Original Description]

https://bugs.launchpad.net/ubuntu/+source/linux-raspi/+bug/2041741/comments/9

@waveform I'm not sure if that is the final solution. With your build speed control works but the set hysteresis (default: 5°C) seems to be ignored. This results in very frequent changes around trip points.

Did you just fix the uninitialized variable or apply the whole commit (https://github.com/raspberrypi/linux/commit/29d2bdf66191b6e50deef2110792c43c10cccfd9)?

E.g. lots of changes between states 0 and 1, with the fan sometimes stopping for just a fraction of a second:

[Juerg Haefliger (juergh)]

https://github.com/raspberrypi/linux/pull/5736/commits/a57989416faf34a4d7358f3786c0de52e5af81cc

[Jürgen Kreileder (jk)]

For reference: The fix has been merged in raspberrypi:rpi-6.5.y

[Juerg Haefliger (juergh)]

Oh, I'm inclined to shove this into the current cycle then. Are you willing to test it then?

[Jürgen Kreileder (jk)]

Sure. Do you have test builds or do I have to build from git?

[Jürgen Kreileder (jk)]

I tested 6.5.0-1008.11 + https://github.com/raspberrypi/linux/commit/d3668f4e7e2747f38d7f680df231f02dd33d3a13 => hysteresis works like expected on my Pi 4 (1 trip) and Pi 5 (4 trips).

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This bug is awaiting verification that the linux-raspi/6.5.0-1010.13 kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-mantic-linux-raspi' to 'verification-done-mantic-linux-raspi'. If the problem still exists, change the tag 'verification-needed-mantic-linux-raspi' to 'verification-failed-mantic-linux-raspi'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

[Jürgen Kreileder (jk)]

Works for me.

[Launchpad Janitor (janitor)]

This bug was fixed in the package linux-raspi - 6.5.0-1010.13

---------------
linux-raspi (6.5.0-1010.13) mantic; urgency=medium

  * mantic/linux-raspi: 6.5.0-1010.13 -proposed tracker (LP: #2048364)

  * Packaging resync (LP: #1786013)
    - debian/dkms-versions -- update from kernel-versions (main/2024.01.08)

  * vc4-drm gpu: [drm] *ERROR* Failed to allocate DLIST entry: -28
    (LP: #2046584)
    - drm: Look for an alias for the displays to use as the DRM device name
    - vc4/drm: Remove the clear of SCALER_DISPBKGND_FILL
    - drm/vc4: Correct address offset for planes with src_[xy] offsets
    - fbdev: Allow client to request a particular /dev/fbN node
    - drm/fb-helper: Look up preferred fbdev node number from DT
    - drm/connector: Change DRM card alias from underscore to hyphen
    - drm/fb_helper: Change query for FB designation from drm_fb to drm-fb
    - drm/vc4: Correct logic on stopping an HVS channel
    - drm/vc4: Drop WARN for HVS FIFOs not being empty
    - drm/vc4: Free all stale dlists if channel is disabled
    - drm/vc4: Add hvs_dlist_allocs debugfs function.
    - drm/vc4: Log the size of the dlist allocation that was attempted
    - drm/vc4: crtc: Support odd horizontal timings on BCM2712
    - drm/vc4: Drop planes that are completely off-screen
    - drm/bridge: display-connector: Select DRM_KMS_HELPER
    - drm: vc4: Free the dlist alloc immediately if it never hit the hw
    - drm: vc4: Block swiotlb bounce buffers being imported as dmabuf
    - drm/vc4: vec: Add the margin properties to the connector
    - drm: panel: jdi-lt070me05000: Add prepare_upstream_first flag
    - drm/panel: add panel-dsi
    - drm/vc4: Correct HVS muxing setup for the moplet
    - drm/vc4: Mop and moplet have different register offsets for high addr
    - drm/vc4: Fix reading of frame count on GEN5 / Pi4
    - drm/vc4: Fixup of patches adding debugfs functions
    - drm/vc4: hvs: Fix compile warnings

  * spidev0 missing on raspberrypi5 on ubuntu 23.10 server and desktop version
    (LP: #2045947)
    - [Config] raspi: Set DW_AXI_DMAC=m

  * Fan toggles on/off repeatedly (LP: #2044341)
    - Fix hysteresis support in gov_step_wise.c (#5736)

  [ Ubuntu: 6.5.0-17.17 ]

  * mantic/linux: 6.5.0-17.17 -proposed tracker (LP: #2049026)
  * [UBUNTU 23.04] Regression: Ubuntu 23.04/23.10 do not include uvdevice
    anymore (LP: #2048919)
    - [Config] Enable S390_UV_UAPI (built-in)

  [ Ubuntu: 6.5.0-16.16 ]

  * mantic/linux: 6.5.0-16.16 -proposed tracker (LP: #2048372)
  * Packaging resync (LP: #1786013)
    - [Packaging] resync git-ubuntu-log
    - [Packaging] resync update-dkms-versions helper
    - [Packaging] remove helper scripts
    - [Packaging] update annotations scripts
    - debian/dkms-versions -- update from kernel-versions (main/2024.01.08)
  * Add missing RPL P/U CPU IDs (LP: #2047398)
    - drm/i915/rpl: Update pci ids for RPL P/U
  * Fix BCM57416 lost after resume (LP: #2047518)
    - bnxt_en: Clear resource reservation during resume
  * Hotplugging SCSI disk in QEMU VM fails (LP: #2047382)
    - Revert "PCI: acpiphp: Reassign resources on bridge if necessary"
  * Update bnxt_en with bug fixes and support for Broadcom 5760...

[Launchpad Janitor (janitor)]

This bug was fixed in the package linux-raspi - 6.7.0-1001.1

---------------
linux-raspi (6.7.0-1001.1) noble; urgency=medium

  * noble/linux-raspi: 6.7.0-1001.1 -proposed tracker (LP: #2051136)

  * Packaging resync (LP: #1786013)
    - [Packaging] update Ubuntu.md
    - [Packaging] update update.conf
    - debian/dkms-versions -- update from kernel-versions (main/d2024.01.02)

  * Remove linux-modules-extra (LP: #2048862)
    - [Packaging] raspi: Remove linux-modules-extra package

  * Make dwc2 the default (LP: #2048861)
    - SAUCE: ARM: dts: bcm27xx: Make dwc2 the default

  * Raspberry Pi 3B+ doesnt boot from USB on 23.10 Mantic (LP: #2039786)
    - SAUCE: Revert "usb: misc: onboard-hub: add support for Microchip USB2514B
      USB 2.0 hub"

  * Missing overlays/README (LP: #1954757)
    - SAUCE: (no-up) Install overlays/README

  * [Raspberry Pi/lunar] systemd-oomd fails with
    "ConditionControlGroupController=memory was not met" (LP: #2017209)
    - SAUCE: Revert "cgroup: Disable cgroup "memory" by default"

  * Remove armhf support (LP: #2048864)
    - [Packaging] raspi: Remove armhf packages
    - [Packaging] raspi: Remove armhf ABI files

  * Miscellaneous Ubuntu changes
    - [Packaging] raspi: Initial import of debian.raspi from mantic:linux-raspi
      (6.5.0-1010.13)
    - [Packaging] raspi: Sync packaging files from debian.master
    - [Packaging] raspi: Initial version of linux-raspi for Noble
    - [Config] raspi: updateconfigs after rebase to Ubuntu-6.7.0-2.2
    - [Config] raspi: Include master annotations
    - [Packaging] raspi: Disable all ABI checks
    - SAUCE: Revert "iommu: Retire map/unmap ops"
    - [Packaging] raspi: Import of upstream raspberrypi patchset
    - [Config] raspi: updateconfigs after import of rpi-6.6.y patchset
    - [Config] raspi: Set SWIOTLB_DYNAMIC=n
    - SAUCE: arm64: dts: broadcom: Remove downstream dt overlay support
    - SAUCE: (no-up) ARM: dts: Disable unsupported Raspberry Pi DTBs
    - SAUCE: ARM: dts: Fix broken symlinks
    - SAUCE: ARM: dts: overlays: Fix file permissions
    - [Packaging] raspi: Update reconstruct script

  * Miscellaneous upstream changes
    - raspberrypi-firmware: Update mailbox commands
    - drm/vc4: Add FKMS as an acceptable node for dma ranges.
    - drm/atomic: Don't fixup modes that haven't been reset
    - drm/vc4: Allow setting the TV norm via module parameter
    - drm/vc4: Add firmware-kms mode
    - drm/vc4: Add support for gamma on BCM2711
    - drm/vc4: Add debugfs node that dumps the vc5 gamma PWL entries
    - drm/vc4: hvs: Force modeset on gamma lut change
    - drm/vc4: Relax VEC modeline requirements and add progressive mode support
    - drm/vc4: Make VEC progressive modes readily accessible
    - drm: Check whether the gamma lut has changed before updating
    - drm/vc4: Enable gamma block only when required.
    - drm/vc4: Only add gamma properties once.
    - drm/vc4: Validate the size of the gamma_lut
    - drm/vc4: Disable Gamma control on HVS5 due to issues writing the table
    - drm/dsi: Document the meaning and spec references for MIPI_DSI_MODE_*
    - drm/bridge: tc358762: Ignore EPROBE_DEFER when logging errors
    - vc4/drm: vc...