FAILED: patch "[PATCH] spi: slave-mt27xx: fix controller deregistration" failed to apply to 5.15-stable tree

[<gregkh@linuxfoundation.org>]

The patch below does not apply to the 5.15-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x ab840cbda4fe6c40e52f6415c47056797c663bb2
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2026051506-swore-tattling-19dc@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From ab840cbda4fe6c40e52f6415c47056797c663bb2 Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan@kernel.org>
Date: Fri, 10 Apr 2026 10:17:45 +0200
Subject: [PATCH] spi: slave-mt27xx: fix controller deregistration

Make sure to deregister the controller before disabling underlying
resources like clocks (by disabling runtime PM) during driver unbind.

Fixes: 805be7ddf367 ("spi: mediatek: add spi slave for Mediatek MT2712")
Cc: stable@vger.kernel.org	# 4.20
Cc: Leilk Liu <leilk.liu@mediatek.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://patch.msgid.link/20260410081757.503099-16-johan@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/drivers/spi/spi-slave-mt27xx.c b/drivers/spi/spi-slave-mt27xx.c
index ce889cb33228..7aedeaa5889d 100644
--- a/drivers/spi/spi-slave-mt27xx.c
+++ b/drivers/spi/spi-slave-mt27xx.c
@@ -453,7 +453,7 @@ static int mtk_spi_slave_probe(struct platform_device *pdev)
 
 	pm_runtime_enable(&pdev->dev);
 
-	ret = devm_spi_register_controller(&pdev->dev, ctlr);
+	ret = spi_register_controller(ctlr);
 	clk_disable_unprepare(mdata->spi_clk);
 	if (ret) {
 		dev_err(&pdev->dev,
@@ -473,7 +473,15 @@ static int mtk_spi_slave_probe(struct platform_device *pdev)
 
 static void mtk_spi_slave_remove(struct platform_device *pdev)
 {
+	struct spi_controller *ctlr = platform_get_drvdata(pdev);
+
+	spi_controller_get(ctlr);
+
+	spi_unregister_controller(ctlr);
+
 	pm_runtime_disable(&pdev->dev);
+
+	spi_controller_put(ctlr);
 }
 
 #ifdef CONFIG_PM_SLEEP