linux-kernel - [PATCH v5 02/24] i2c: designware: Fix reset call order in dw_i2c_plat

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Message-ID: <20231207141653.2785124-3-andriy.shevchenko@linux.intel.com>
Date:   Thu,  7 Dec 2023 16:13:42 +0200
From:   Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
To:     Mario Limonciello <mario.limonciello@....com>,
        Jarkko Nikula <jarkko.nikula@...ux.intel.com>,
        Herbert Xu <herbert@...dor.apana.org.au>,
        Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        Wolfram Sang <wsa@...nel.org>,
        Andi Shyti <andi.shyti@...nel.org>, linux-i2c@...r.kernel.org,
        linux-kernel@...r.kernel.org
Cc:     Mika Westerberg <mika.westerberg@...ux.intel.com>,
        Jan Dabros <jsd@...ihalf.com>,
        Philipp Zabel <p.zabel@...gutronix.de>,
        Serge Semin <fancer.lancer@...il.com>
Subject: [PATCH v5 02/24] i2c: designware: Fix reset call order in dw_i2c_plat_probe()

We should not mix managed calls with non-managed. This will break
the calls order at the error path and ->remove() stages. Fix this
by wrapping reset control to become managed one.

With that start checking the rerurn code from reset_control_deassert()
as it may fail and calling assertion in that scenario is not always
a good idea.

Reviewed-by: Andi Shyti <andi.shyti@...nel.org>
Tested-by: Serge Semin <fancer.lancer@...il.com>
Acked-by: Jarkko Nikula <jarkko.nikula@...ux.intel.com>
Link: https://lore.kernel.org/r/20231120144641.1660574-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
---
 drivers/i2c/busses/i2c-designware-platdrv.c | 62 +++++++++++----------
 1 file changed, 34 insertions(+), 28 deletions(-)

diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c
index fd3cd65f9c88..648fb84e574d 100644
--- a/drivers/i2c/busses/i2c-designware-platdrv.c
+++ b/drivers/i2c/busses/i2c-designware-platdrv.c
@@ -285,6 +285,28 @@ static void i2c_dw_remove_lock_support(struct dw_i2c_dev *dev)
 		i2c_dw_semaphore_cb_table[dev->semaphore_idx].remove(dev);
 }
 
+static void dw_i2c_plat_assert_reset(void *data)
+{
+	struct dw_i2c_dev *dev = data;
+
+	reset_control_assert(dev->rst);
+}
+
+static int dw_i2c_plat_get_reset(struct dw_i2c_dev *dev)
+{
+	int ret;
+
+	dev->rst = devm_reset_control_get_optional_exclusive(dev->dev, NULL);
+	if (IS_ERR(dev->rst))
+		return PTR_ERR(dev->rst);
+
+	ret = reset_control_deassert(dev->rst);
+	if (ret)
+		return ret;
+
+	return devm_add_action_or_reset(dev->dev, dw_i2c_plat_assert_reset, dev);
+}
+
 static int dw_i2c_plat_probe(struct platform_device *pdev)
 {
 	struct i2c_adapter *adap;
@@ -312,11 +334,9 @@ static int dw_i2c_plat_probe(struct platform_device *pdev)
 	if (ret)
 		return ret;
 
-	dev->rst = devm_reset_control_get_optional_exclusive(&pdev->dev, NULL);
-	if (IS_ERR(dev->rst))
-		return PTR_ERR(dev->rst);
-
-	reset_control_deassert(dev->rst);
+	ret = dw_i2c_plat_get_reset(dev);
+	if (ret)
+		return ret;
 
 	t = &dev->timings;
 	i2c_parse_fw_timings(&pdev->dev, t, false);
@@ -331,30 +351,26 @@ static int dw_i2c_plat_probe(struct platform_device *pdev)
 
 	ret = i2c_dw_validate_speed(dev);
 	if (ret)
-		goto exit_reset;
+		return ret;
 
 	ret = i2c_dw_probe_lock_support(dev);
 	if (ret)
-		goto exit_reset;
+		return ret;
 
 	i2c_dw_configure(dev);
 
 	/* Optional interface clock */
 	dev->pclk = devm_clk_get_optional(&pdev->dev, "pclk");
-	if (IS_ERR(dev->pclk)) {
-		ret = PTR_ERR(dev->pclk);
-		goto exit_reset;
-	}
+	if (IS_ERR(dev->pclk))
+		return PTR_ERR(dev->pclk);
 
 	dev->clk = devm_clk_get_optional(&pdev->dev, NULL);
-	if (IS_ERR(dev->clk)) {
-		ret = PTR_ERR(dev->clk);
-		goto exit_reset;
-	}
+	if (IS_ERR(dev->clk))
+		return PTR_ERR(dev->clk);
 
 	ret = i2c_dw_prepare_clk(dev, true);
 	if (ret)
-		goto exit_reset;
+		return ret;
 
 	if (dev->clk) {
 		u64 clk_khz;
@@ -395,17 +411,9 @@ static int dw_i2c_plat_probe(struct platform_device *pdev)
 
 	ret = dw_i2c_plat_pm_setup(dev);
 	if (ret)
-		goto exit_reset;
+		return ret;
 
-	ret = i2c_dw_probe(dev);
-	if (ret)
-		goto exit_reset;
-
-	return ret;
-
-exit_reset:
-	reset_control_assert(dev->rst);
-	return ret;
+	return i2c_dw_probe(dev);
 }
 
 static void dw_i2c_plat_remove(struct platform_device *pdev)
@@ -422,8 +430,6 @@ static void dw_i2c_plat_remove(struct platform_device *pdev)
 	pm_runtime_put_sync(&pdev->dev);
 
 	i2c_dw_remove_lock_support(dev);
-
-	reset_control_assert(dev->rst);
 }
 
 static int dw_i2c_plat_prepare(struct device *dev)
-- 
2.43.0.rc1.1.gbec44491f096