[PATCH v2 1/3] spi: mt65xx: Properly handle failures in .remove()

Uwe Kleine-König u.kleine-koenig at pengutronix.de
Tue May 30 01:16:46 PDT 2023


Returning an error code in a platform driver's remove function is wrong
most of the time and there is an effort to make the callback return
void. To prepare this rework the function not to exit early.

There wasn't a real problem because if pm runtime resume failed the only
step missing was pm_runtime_disable() which isn't an issue.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig at pengutronix.de>
---
 drivers/spi/spi-mt65xx.c | 22 ++++++++++++++--------
 1 file changed, 14 insertions(+), 8 deletions(-)

diff --git a/drivers/spi/spi-mt65xx.c b/drivers/spi/spi-mt65xx.c
index 21c321f43766..9333a0e8204d 100644
--- a/drivers/spi/spi-mt65xx.c
+++ b/drivers/spi/spi-mt65xx.c
@@ -1275,15 +1275,21 @@ static int mtk_spi_remove(struct platform_device *pdev)
 	struct mtk_spi *mdata = spi_master_get_devdata(master);
 	int ret;
 
-	ret = pm_runtime_resume_and_get(&pdev->dev);
-	if (ret < 0)
-		return ret;
+	ret = pm_runtime_get_sync(&pdev->dev);
+	if (ret < 0) {
+		dev_warn(&pdev->dev, "Failed to resume hardware (%pe)\n", ERR_PTR(ret));
+	} else {
+		/*
+		 * If pm runtime resume failed, clks are disabled and
+		 * unprepared. So don't access the hardware and skip clk
+		 * unpreparing.
+		 */
+		mtk_spi_reset(mdata);
 
-	mtk_spi_reset(mdata);
-
-	if (mdata->dev_comp->no_need_unprepare) {
-		clk_unprepare(mdata->spi_clk);
-		clk_unprepare(mdata->spi_hclk);
+		if (mdata->dev_comp->no_need_unprepare) {
+			clk_unprepare(mdata->spi_clk);
+			clk_unprepare(mdata->spi_hclk);
+		}
 	}
 
 	pm_runtime_put_noidle(&pdev->dev);
-- 
2.39.2




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