* [PATCH AUTOSEL 6.0 17/39] spi: mediatek: Fix DEVAPC Violation at KO Remove
[not found] <20221128173642.1441232-1-sashal@kernel.org>
@ 2022-11-28 17:35 ` Sasha Levin
0 siblings, 0 replies; only message in thread
From: Sasha Levin @ 2022-11-28 17:35 UTC (permalink / raw)
To: linux-kernel, stable
Cc: Zhichao Liu, AngeloGioacchino Del Regno, Mark Brown, Sasha Levin,
matthias.bgg, linux-spi, linux-arm-kernel, linux-mediatek
From: Zhichao Liu <zhichao.liu@mediatek.com>
[ 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@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20221110072839.30961-1-zhichao.liu@mediatek.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/spi/spi-mt65xx.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/drivers/spi/spi-mt65xx.c b/drivers/spi/spi-mt65xx.c
index cd9dc358d396..a7cc96aeb590 100644
--- a/drivers/spi/spi-mt65xx.c
+++ b/drivers/spi/spi-mt65xx.c
@@ -1268,8 +1268,11 @@ 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);
@@ -1278,6 +1281,9 @@ static int mtk_spi_remove(struct platform_device *pdev)
clk_unprepare(mdata->spi_hclk);
}
+ pm_runtime_put_noidle(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+
return 0;
}
--
2.35.1
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2022-11-28 17:35 ` [PATCH AUTOSEL 6.0 17/39] spi: mediatek: Fix DEVAPC Violation at KO Remove Sasha Levin
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