This is a note to let you know that I've just added the patch titled spi: stm32-qspi: fix pm_runtime usage_count counter to the 5.11-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: spi-stm32-qspi-fix-pm_runtime-usage_count-counter.patch and it can be found in the queue-5.11 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 102e9d1936569d43f55dd1ea89be355ad207143c Mon Sep 17 00:00:00 2001 From: Christophe Kerello <christophe.kerello@xxxxxxxxxxx> Date: Mon, 19 Apr 2021 14:15:39 +0200 Subject: spi: stm32-qspi: fix pm_runtime usage_count counter From: Christophe Kerello <christophe.kerello@xxxxxxxxxxx> commit 102e9d1936569d43f55dd1ea89be355ad207143c upstream. 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@xxxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Link: https://lore.kernel.org/r/20210419121541.11617-2-patrice.chotard@xxxxxxxxxxx Signed-off-by: Mark Brown <broonie@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/spi/spi-stm32-qspi.c | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-) --- a/drivers/spi/spi-stm32-qspi.c +++ b/drivers/spi/spi-stm32-qspi.c @@ -727,21 +727,31 @@ static int __maybe_unused stm32_qspi_sus { 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; } Patches currently in stable-queue which might be from christophe.kerello@xxxxxxxxxxx are queue-5.11/spi-stm32-qspi-fix-pm_runtime-usage_count-counter.patch