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>

diff --git a/drivers/spi/spi-cadence-quadspi.c b/drivers/spi/spi-cadence-quadspi.c
index fe0f122f07b0206e80cf89bd031106bf8051c789..aa1932ba17cb89194d0c3740047c855f6ec316e7 100644 (file)
--- a/drivers/spi/spi-cadence-quadspi.c
+++ b/drivers/spi/spi-cadence-quadspi.c
@@ -1958,10 +1958,10 @@ static int cqspi_probe(struct platform_device *pdev)
                        goto probe_setup_failed;
        }
 
-       ret = devm_pm_runtime_enable(dev);
-       if (ret) {
-               if (cqspi->rx_chan)
-                       dma_release_channel(cqspi->rx_chan);
+       pm_runtime_enable(dev);
+
+       if (cqspi->rx_chan) {
+               dma_release_channel(cqspi->rx_chan);
                goto probe_setup_failed;
        }
 
@@ -1981,6 +1981,7 @@ 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);
@@ -1999,7 +2000,8 @@ 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);