This is a note to let you know that I've just added the patch titled
spi: mediatek: Fix DEVAPC Violation at KO Remove
to the 5.15-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-mediatek-fix-devapc-violation-at-ko-remove.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit ddb9f1bf0ea7d86add91a26b10b18424082b9e0f
Author: Zhichao Liu <zhichao.liu@xxxxxxxxxxxx>
Date: Thu Nov 10 15:28:39 2022 +0800
spi: mediatek: Fix DEVAPC Violation at KO Remove
[ Upstream commit 0d10e90cee9eb57882b0f7e19fd699033722e226 ]
A DEVAPC violation occurs when removing the module
due to accessing HW registers without base clock.
To fix this bug, the correct method is:
1. Call the runtime resume function to enable the
clock;
2. Operate the registers to reset the HW;
3. Turn off the clocks and disable the device
RPM mechanism.
Signed-off-by: Zhichao Liu <zhichao.liu@xxxxxxxxxxxx>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20221110072839.30961-1-zhichao.liu@xxxxxxxxxxxx
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/spi/spi-mt65xx.c b/drivers/spi/spi-mt65xx.c
index 2ca19b01948a..49acba1dea1e 100644
--- a/drivers/spi/spi-mt65xx.c
+++ b/drivers/spi/spi-mt65xx.c
@@ -912,14 +912,20 @@ static int mtk_spi_remove(struct platform_device *pdev)
{
struct spi_master *master = platform_get_drvdata(pdev);
struct mtk_spi *mdata = spi_master_get_devdata(master);
+ int ret;
- pm_runtime_disable(&pdev->dev);
+ ret = pm_runtime_resume_and_get(&pdev->dev);
+ if (ret < 0)
+ return ret;
mtk_spi_reset(mdata);
if (mdata->dev_comp->no_need_unprepare)
clk_unprepare(mdata->spi_clk);
+ pm_runtime_put_noidle(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+
return 0;
}
