spi: spi-cadence-quadspi: Fix pm runtime unbalance
authorKhairul Anuar Romli <khairul.anuar.romli@altera.com>
Mon, 16 Jun 2025 01:13:53 +0000 (09:13 +0800)
committerMark Brown <broonie@kernel.org>
Tue, 24 Jun 2025 15:40:31 +0000 (16:40 +0100)
commitb07f349d1864abe29436f45e3047da2bdd476462
tree87dc893743eb68fdc7d10f802311a3d04357aa7a
parent86731a2a651e58953fc949573895f2fa6d456841
spi: spi-cadence-quadspi: Fix pm runtime unbalance

Having PM put sync in remove function is causing PM underflow during
remove operation. This is caused by the function, runtime_pm_get_sync,
not being called anywhere during the op. Ensure that calls to
pm_runtime_enable()/pm_runtime_disable() and
pm_runtime_get_sync()/pm_runtime_put_sync() match.

echo 108d2000.spi > /sys/bus/platform/drivers/cadence-qspi/unbind
[   49.644256] Deleting MTD partitions on "108d2000.spi.0":
[   49.649575] Deleting u-boot MTD partition
[   49.684087] Deleting root MTD partition
[   49.724188] cadence-qspi 108d2000.spi: Runtime PM usage count underflow!

Continuous bind/unbind will result in an "Unbalanced pm_runtime_enable" error.
Subsequent unbind attempts will return a "No such device" error, while bind
attempts will return a "Resource temporarily unavailable" error.

[   47.592434] cadence-qspi 108d2000.spi: Runtime PM usage count underflow!
[   49.592233] cadence-qspi 108d2000.spi: detected FIFO depth (1024) different from config (128)
[   53.232309] cadence-qspi 108d2000.spi: Runtime PM usage count underflow!
[   55.828550] cadence-qspi 108d2000.spi: detected FIFO depth (1024) different from config (128)
[   57.940627] cadence-qspi 108d2000.spi: Runtime PM usage count underflow!
[   59.912490] cadence-qspi 108d2000.spi: detected FIFO depth (1024) different from config (128)
[   61.876243] cadence-qspi 108d2000.spi: Runtime PM usage count underflow!
[   61.883000] platform 108d2000.spi: Unbalanced pm_runtime_enable!
[  532.012270] cadence-qspi 108d2000.spi: probe with driver cadence-qspi failed1

Also, change clk_disable_unprepare() to clk_disable() since continuous
bind and unbind operations will trigger a warning indicating that the clock is
already unprepared.

Fixes: 4892b374c9b7 ("mtd: spi-nor: cadence-quadspi: Add runtime PM support")
cc: stable@vger.kernel.org # 6.6+
Signed-off-by: Khairul Anuar Romli <khairul.anuar.romli@altera.com>
Reviewed-by: Matthew Gerlach <matthew.gerlach@altera.com>
Link: https://patch.msgid.link/4e7a4b8aba300e629b45a04f90bddf665fbdb335.1749601877.git.khairul.anuar.romli@altera.com
Signed-off-by: Mark Brown <broonie@kernel.org>
drivers/spi/spi-cadence-quadspi.c