From: Khairul Anuar Romli khairul.anuar.romli@altera.com
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... Signed-off-by: Mark Brown broonie@kernel.org (cherry picked from commit b07f349d1864abe29436f45e3047da2bdd476462) --- drivers/spi/spi-cadence-quadspi.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-)
diff --git a/drivers/spi/spi-cadence-quadspi.c b/drivers/spi/spi-cadence-quadspi.c index bf9b816637d0..9285a683324f 100644 --- a/drivers/spi/spi-cadence-quadspi.c +++ b/drivers/spi/spi-cadence-quadspi.c @@ -1868,6 +1868,13 @@ static int cqspi_probe(struct platform_device *pdev) goto probe_setup_failed; }
+ pm_runtime_enable(dev); + + if (cqspi->rx_chan) { + dma_release_channel(cqspi->rx_chan); + goto probe_setup_failed; + } + ret = spi_register_controller(host); if (ret) { dev_err(&pdev->dev, "failed to register SPI ctlr %d\n", ret); @@ -1877,6 +1884,7 @@ static int cqspi_probe(struct platform_device *pdev) return 0; probe_setup_failed: cqspi_controller_enable(cqspi, 0); + pm_runtime_disable(dev); probe_reset_failed: if (cqspi->is_jh7110) cqspi_jh7110_disable_clk(pdev, cqspi); @@ -1898,7 +1906,8 @@ static void cqspi_remove(struct platform_device *pdev) if (cqspi->rx_chan) dma_release_channel(cqspi->rx_chan);
- clk_disable_unprepare(cqspi->clk); + if (pm_runtime_get_sync(&pdev->dev) >= 0) + clk_disable(cqspi->clk);
if (cqspi->is_jh7110) cqspi_jh7110_disable_clk(pdev, cqspi);