[PATCH] [v4] spi: spi-zynqmp-gqspi: Fix runtime PM imbalance in zynqmp_qspi_probe

From: Dinghao Liu
Date: Thu Apr 15 2021 - 03:47:07 EST


There is a PM usage counter decrement after zynqmp_qspi_init_hw()
without any refcount increment, which leads to refcount leak.Add
a refcount increment to balance the refcount. Also set
auto_runtime_pm to resume suspended spi controller.

Fixes: 9e3a000362aec ("spi: zynqmp: Add pm runtime support")
Signed-off-by: Dinghao Liu <dinghao.liu@xxxxxxxxxx>
---

Changelog:

v2: - Add a refcount increment to fix refcout leak instead of the
refcount decrement on error.
Set ctlr->auto_runtime_pm = true.

v3: - Add fix tag.
Add a return value check against pm_runtime_get_sync().
Move pm_runtime_{mark_last_busy & put_autosuspend} to the
end of current function.

v4: - Add error message on failure of pm_runtime_get_sync().
---
drivers/spi/spi-zynqmp-gqspi.c | 14 ++++++++++++--
1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/spi/spi-zynqmp-gqspi.c b/drivers/spi/spi-zynqmp-gqspi.c
index c8fa6ee18ae7..38f3ddd3ea7c 100644
--- a/drivers/spi/spi-zynqmp-gqspi.c
+++ b/drivers/spi/spi-zynqmp-gqspi.c
@@ -1160,11 +1160,16 @@ static int zynqmp_qspi_probe(struct platform_device *pdev)
pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
pm_runtime_set_active(&pdev->dev);
pm_runtime_enable(&pdev->dev);
+
+ ret = pm_runtime_get_sync(&pdev->dev);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Failed to pm_runtime_get_sync: %d\n", ret);
+ goto clk_dis_all;
+ }
+
/* QSPI controller initializations */
zynqmp_qspi_init_hw(xqspi);

- pm_runtime_mark_last_busy(&pdev->dev);
- pm_runtime_put_autosuspend(&pdev->dev);
xqspi->irq = platform_get_irq(pdev, 0);
if (xqspi->irq <= 0) {
ret = -ENXIO;
@@ -1187,6 +1192,7 @@ static int zynqmp_qspi_probe(struct platform_device *pdev)
ctlr->mode_bits = SPI_CPOL | SPI_CPHA | SPI_RX_DUAL | SPI_RX_QUAD |
SPI_TX_DUAL | SPI_TX_QUAD;
ctlr->dev.of_node = np;
+ ctlr->auto_runtime_pm = true;

ret = devm_spi_register_controller(&pdev->dev, ctlr);
if (ret) {
@@ -1194,9 +1200,13 @@ static int zynqmp_qspi_probe(struct platform_device *pdev)
goto clk_dis_all;
}

+ pm_runtime_mark_last_busy(&pdev->dev);
+ pm_runtime_put_autosuspend(&pdev->dev);
+
return 0;

clk_dis_all:
+ pm_runtime_put_sync(&pdev->dev);
pm_runtime_set_suspended(&pdev->dev);
pm_runtime_disable(&pdev->dev);
clk_disable_unprepare(xqspi->refclk);
--
2.17.1