[PATCH 1/3] spi: stm32-qspi: fix pm_runtime usage_count counter
patrice.chotard at foss.st.com
patrice.chotard at foss.st.com
Mon Apr 19 13:15:39 BST 2021
From: Christophe Kerello <christophe.kerello at foss.st.com>
pm_runtime usage_count counter is not well managed.
pm_runtime_put_autosuspend callback drops the usage_counter but this
one has never been increased. Add pm_runtime_get_sync callback to bump up
the usage counter. It is also needed to use pm_runtime_force_suspend and
pm_runtime_force_resume APIs to handle properly the clock.
Fixes: 9d282c17b023 ("spi: stm32-qspi: Add pm_runtime support")
Signed-off-by: Christophe Kerello <christophe.kerello at foss.st.com>
Cc: stable at vger.kernel.org
---
drivers/spi/spi-stm32-qspi.c | 18 ++++++++++++++----
1 file changed, 14 insertions(+), 4 deletions(-)
diff --git a/drivers/spi/spi-stm32-qspi.c b/drivers/spi/spi-stm32-qspi.c
index 947e6b9dc9f4..2786470a5201 100644
--- a/drivers/spi/spi-stm32-qspi.c
+++ b/drivers/spi/spi-stm32-qspi.c
@@ -727,21 +727,31 @@ static int __maybe_unused stm32_qspi_suspend(struct device *dev)
{
pinctrl_pm_select_sleep_state(dev);
- return 0;
+ return pm_runtime_force_suspend(dev);
}
static int __maybe_unused stm32_qspi_resume(struct device *dev)
{
struct stm32_qspi *qspi = dev_get_drvdata(dev);
+ int ret;
+
+ ret = pm_runtime_force_resume(dev);
+ if (ret < 0)
+ return ret;
pinctrl_pm_select_default_state(dev);
- clk_prepare_enable(qspi->clk);
+
+ ret = pm_runtime_get_sync(dev);
+ if (ret < 0) {
+ pm_runtime_put_noidle(dev);
+ return ret;
+ }
writel_relaxed(qspi->cr_reg, qspi->io_base + QSPI_CR);
writel_relaxed(qspi->dcr_reg, qspi->io_base + QSPI_DCR);
- pm_runtime_mark_last_busy(qspi->dev);
- pm_runtime_put_autosuspend(qspi->dev);
+ pm_runtime_mark_last_busy(dev);
+ pm_runtime_put_autosuspend(dev);
return 0;
}
--
2.17.1
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