[PATCH v4 21/23] counter: stm32-lptimer-cnt: Convert to new counter registration - Uwe Kleine-König

From: "Uwe Kleine-König" <u.kleine-koenig@pengutronix.de>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org,
	kernel@pengutronix.de,
	Jonathan Cameron <Jonathan.Cameron@huawei.com>,
	Fabrice Gasnier <fabrice.gasnier@foss.st.com>,
	Maxime Coquelin <mcoquelin.stm32@gmail.com>,
	Alexandre Torgue <alexandre.torgue@foss.st.com>,
	linux-stm32@st-md-mailman.stormreply.com,
	linux-arm-kernel@lists.infradead.org,
	William Breathitt Gray <vilhelm.gray@gmail.com>
Subject: [PATCH v4 21/23] counter: stm32-lptimer-cnt: Convert to new counter registration
Date: Thu, 30 Dec 2021 16:02:58 +0100	[thread overview]
Message-ID: <20211230150300.72196-22-u.kleine-koenig@pengutronix.de> (raw)
In-Reply-To: <20211230150300.72196-1-u.kleine-koenig@pengutronix.de>

This fixes device lifetime issues where it was possible to free a live
struct device.

Fixes: 597f55e3f36c ("counter: stm32-lptimer: add counter device")
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
---
 drivers/counter/stm32-lptimer-cnt.c | 33 +++++++++++++++++------------
 1 file changed, 19 insertions(+), 14 deletions(-)

diff --git a/drivers/counter/stm32-lptimer-cnt.c b/drivers/counter/stm32-lptimer-cnt.c
index 9cf00e929cc0..68031d93ce89 100644
--- a/drivers/counter/stm32-lptimer-cnt.c
+++ b/drivers/counter/stm32-lptimer-cnt.c
@@ -20,7 +20,6 @@
 #include <linux/types.h>
 
 struct stm32_lptim_cnt {
-	struct counter_device counter;
 	struct device *dev;
 	struct regmap *regmap;
 	struct clk *clk;
@@ -411,14 +410,17 @@ static struct counter_count stm32_lptim_in1_counts = {
 static int stm32_lptim_cnt_probe(struct platform_device *pdev)
 {
 	struct stm32_lptimer *ddata = dev_get_drvdata(pdev->dev.parent);
+	struct counter_device *counter;
 	struct stm32_lptim_cnt *priv;
+	int ret;
 
 	if (IS_ERR_OR_NULL(ddata))
 		return -EINVAL;
 
-	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
-	if (!priv)
+	counter = devm_counter_alloc(&pdev->dev, sizeof(*priv));
+	if (!counter)
 		return -ENOMEM;
+	priv = counter_priv(counter);
 
 	priv->dev = &pdev->dev;
 	priv->regmap = ddata->regmap;
@@ -426,23 +428,26 @@ static int stm32_lptim_cnt_probe(struct platform_device *pdev)
 	priv->ceiling = STM32_LPTIM_MAX_ARR;
 
 	/* Initialize Counter device */
-	priv->counter.name = dev_name(&pdev->dev);
-	priv->counter.parent = &pdev->dev;
-	priv->counter.ops = &stm32_lptim_cnt_ops;
+	counter->name = dev_name(&pdev->dev);
+	counter->parent = &pdev->dev;
+	counter->ops = &stm32_lptim_cnt_ops;
 	if (ddata->has_encoder) {
-		priv->counter.counts = &stm32_lptim_enc_counts;
-		priv->counter.num_signals = ARRAY_SIZE(stm32_lptim_cnt_signals);
+		counter->counts = &stm32_lptim_enc_counts;
+		counter->num_signals = ARRAY_SIZE(stm32_lptim_cnt_signals);
 	} else {
-		priv->counter.counts = &stm32_lptim_in1_counts;
-		priv->counter.num_signals = 1;
+		counter->counts = &stm32_lptim_in1_counts;
+		counter->num_signals = 1;
 	}
-	priv->counter.num_counts = 1;
-	priv->counter.signals = stm32_lptim_cnt_signals;
-	priv->counter.priv = priv;
+	counter->num_counts = 1;
+	counter->signals = stm32_lptim_cnt_signals;
 
 	platform_set_drvdata(pdev, priv);
 
-	return devm_counter_register(&pdev->dev, &priv->counter);
+	ret = devm_counter_add(&pdev->dev, counter);
+	if (ret < 0)
+		return dev_err_probe(&pdev->dev, ret, "Failed to add counter\n");
+
+	return 0;
 }
 
 #ifdef CONFIG_PM_SLEEP
-- 
2.34.1

