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Wei Fang 335031cacd net: phy: micrel: fix clk warning when removing the driver
[ Upstream commit 2aa1545ba8 ]

Since the commit 25c6a5ab15 ("net: phy: micrel: Dynamically control
external clock of KSZ PHY"), the clock of Micrel PHY has been enabled
by phy_driver::resume() and disabled by phy_driver::suspend(). However,
devm_clk_get_optional_enabled() is used in kszphy_probe(), so the clock
will automatically be disabled when the device is unbound from the bus.
Therefore, this could cause the clock to be disabled twice, resulting
in clk driver warnings.

For example, this issue can be reproduced on i.MX6ULL platform, and we
can see the following logs when removing the FEC MAC drivers.

$ echo 2188000.ethernet > /sys/bus/platform/drivers/fec/unbind
$ echo 20b4000.ethernet > /sys/bus/platform/drivers/fec/unbind
[  109.758207] ------------[ cut here ]------------
[  109.758240] WARNING: drivers/clk/clk.c:1188 at clk_core_disable+0xb4/0xd0, CPU#0: sh/639
[  109.771011] enet2_ref already disabled
[  109.793359] Call trace:
[  109.822006]  clk_core_disable from clk_disable+0x28/0x34
[  109.827340]  clk_disable from clk_disable_unprepare+0xc/0x18
[  109.833029]  clk_disable_unprepare from devm_clk_release+0x1c/0x28
[  109.839241]  devm_clk_release from devres_release_all+0x98/0x100
[  109.845278]  devres_release_all from device_unbind_cleanup+0xc/0x70
[  109.851571]  device_unbind_cleanup from device_release_driver_internal+0x1a4/0x1f4
[  109.859170]  device_release_driver_internal from bus_remove_device+0xbc/0xe4
[  109.866243]  bus_remove_device from device_del+0x140/0x458
[  109.871757]  device_del from phy_mdio_device_remove+0xc/0x24
[  109.877452]  phy_mdio_device_remove from mdiobus_unregister+0x40/0xac
[  109.883918]  mdiobus_unregister from fec_enet_mii_remove+0x40/0x78
[  109.890125]  fec_enet_mii_remove from fec_drv_remove+0x4c/0x158
[  109.896076]  fec_drv_remove from device_release_driver_internal+0x17c/0x1f4
[  109.962748] WARNING: drivers/clk/clk.c:1047 at clk_core_unprepare+0xfc/0x13c, CPU#0: sh/639
[  109.975805] enet2_ref already unprepared
[  110.002866] Call trace:
[  110.031758]  clk_core_unprepare from clk_unprepare+0x24/0x2c
[  110.037440]  clk_unprepare from devm_clk_release+0x1c/0x28
[  110.042957]  devm_clk_release from devres_release_all+0x98/0x100
[  110.048989]  devres_release_all from device_unbind_cleanup+0xc/0x70
[  110.055280]  device_unbind_cleanup from device_release_driver_internal+0x1a4/0x1f4
[  110.062877]  device_release_driver_internal from bus_remove_device+0xbc/0xe4
[  110.069950]  bus_remove_device from device_del+0x140/0x458
[  110.075469]  device_del from phy_mdio_device_remove+0xc/0x24
[  110.081165]  phy_mdio_device_remove from mdiobus_unregister+0x40/0xac
[  110.087632]  mdiobus_unregister from fec_enet_mii_remove+0x40/0x78
[  110.093836]  fec_enet_mii_remove from fec_drv_remove+0x4c/0x158
[  110.099782]  fec_drv_remove from device_release_driver_internal+0x17c/0x1f4

After analyzing the process of removing the FEC driver, as shown below,
it can be seen that the clock was disabled twice by the PHY driver.

fec_drv_remove()
  --> fec_enet_close()
    --> phy_stop()
      --> phy_suspend()
        --> kszphy_suspend() #1 The clock is disabled
  --> fec_enet_mii_remove()
    --> mdiobus_unregister()
      --> phy_mdio_device_remove()
        --> device_del()
          --> devm_clk_release() #2 The clock is disabled again

Therefore, devm_clk_get_optional() is used to fix the above issue. And
to avoid the issue mentioned by the commit 9853294627 ("net: phy:
micrel: use devm_clk_get_optional_enabled for the rmii-ref clock"), the
clock is enabled by clk_prepare_enable() to get the correct clock rate.

Fixes: 25c6a5ab15 ("net: phy: micrel: Dynamically control external clock of KSZ PHY")
Signed-off-by: Wei Fang <wei.fang@nxp.com>
Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Link: https://patch.msgid.link/20260126081544.983517-1-wei.fang@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
History 2026-02-06 16:57:33 +01:00
arch arm64: dts: qcom: talos: Correct UFS clocks ordering 2026-01-30 10:32:28 +01:00
block block: zero non-PI portion of auto integrity buffer 2026-01-23 11:21:16 +01:00
certs sign-file,extract-cert: use pkcs11 provider for OPENSSL MAJOR >= 3 2024-09-20 19:52:48 +03:00
crypto crypto: authencesn - reject too-short AAD (assoclen<8) to match ESP/ESN spec 2026-01-30 10:32:12 +01:00
Documentation fou: Don't allow 0 for FOU_ATTR_IPPROTO. 2026-01-30 10:32:12 +01:00
drivers net: phy: micrel: fix clk warning when removing the driver 2026-02-06 16:57:33 +01:00
fs btrfs: zlib: fix the folio leak on S390 hardware acceleration 2026-02-06 16:57:29 +01:00
include nfc: nci: Fix race between rfkill and nci_unregister_device(). 2026-02-06 16:57:32 +01:00
init printk changes for 6.18 2025-10-04 11:13:11 -07:00
io_uring io_uring/io-wq: check IO_WQ_BIT_EXIT inside work run loop 2026-01-30 10:32:15 +01:00
ipc namespace-6.18-rc1 2025-09-29 11:20:29 -07:00
kernel tracing: Fix crash on synthetic stacktrace field usage 2026-01-30 10:32:25 +01:00
lib lib/buildid: use __kernel_read() for sleepable context 2026-01-23 11:21:25 +01:00
LICENSES LICENSES: Replace the obsolete address of the FSF in the GFDL-1.2 2025-07-24 11:15:39 +02:00
mm mm/vma: enforce VMA fork limit on unfaulted,faulted mremap merge too 2026-01-30 10:32:28 +01:00
net net: bridge: fix static key check 2026-02-06 16:57:33 +01:00
rust rust: irq: always inline functions using build_assert with arguments 2026-01-30 10:32:26 +01:00
samples samples/ftrace: Adjust LoongArch register restore order in direct calls 2026-01-08 10:17:11 +01:00
scripts kconfig: fix static linking of nconf 2026-01-30 10:32:16 +01:00
security keys/trusted_keys: fix handle passed to tpm_buf_append_name during unseal 2026-01-30 10:32:22 +01:00
sound ALSA: usb-audio: Fix use-after-free in snd_usb_mixer_free() 2026-01-30 10:32:23 +01:00
tools vsock/test: fix seqpacket message bounds test 2026-01-30 10:32:21 +01:00
usr gen_init_cpio: Ignore fsync() returning EINVAL on pipes 2025-10-07 09:53:05 -07:00
virt KVM: Fix last_boosted_vcpu index assignment bug 2026-01-02 12:57:21 +01:00
.clang-format memblock: drop for_each_free_mem_pfn_range_in_zone_from() 2025-09-14 08:49:03 +03:00
.clippy.toml rust: clean Rust 1.88.0's warning about clippy::disallowed_macros configuration 2025-05-07 00:11:47 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.editorconfig .editorconfig: remove trim_trailing_whitespace option 2024-06-13 16:47:52 +02:00
.get_maintainer.ignore MAINTAINERS: remove Alyssa Rosenzweig 2025-09-18 21:17:31 +02:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore .gitignore: ignore compile_commands.json globally 2025-08-12 15:53:55 -07:00
.mailmap 8 hotfixes. 4 are cc:stable, 7 are against mm/. 2025-11-26 12:38:05 -08:00
.pylintrc tools: docs: parse-headers.py: move it from sphinx dir 2025-08-29 15:54:42 -06:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: mark ISDN subsystem as orphan 2025-10-27 17:49:45 -07:00
Kbuild sched: Make migrate_{en,dis}able() inline 2025-09-25 09:57:16 +02:00
Kconfig io_uring: Rename KConfig to Kconfig 2025-02-19 14:53:27 -07:00
MAINTAINERS soc: fixes for 6.18, part 4 2025-11-28 09:57:31 -08:00
Makefile Linux 6.18.8 2026-01-30 10:32:28 +01:00
README README: Fix spelling 2024-03-18 03:36:32 -06:00

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several of them using the reStructuredText markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
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