From:   =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= 
        <u.kleine-koenig@pengutronix.de>
To:     William Breathitt Gray <vilhelm.gray@gmail.com>
Cc:     Lars-Peter Clausen <lars@metafoo.de>, kernel@pengutronix.de,
        Jonathan Cameron <Jonathan.Cameron@huawei.com>,
        linux-iio@vger.kernel.org,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        linux-kernel@vger.kernel.org,
        Syed Nayyar Waris <syednwaris@gmail.com>
Subject: [PATCH v2 15/23] counter: 104-quad-8: Convert to new counter registration
Date:   Mon, 27 Dec 2021 10:45:18 +0100
Message-Id: <20211227094526.698714-16-u.kleine-koenig@pengutronix.de>
In-Reply-To: <20211227094526.698714-1-u.kleine-koenig@pengutronix.de>
References: <20211227094526.698714-1-u.kleine-koenig@pengutronix.de>
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Precedence: bulk

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

Fixes: f1d8a071d45b ("counter: 104-quad-8: Add Generic Counter interface support")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
---
 drivers/counter/104-quad-8.c | 30 +++++++++++++++++-------------
 1 file changed, 17 insertions(+), 13 deletions(-)

diff --git a/drivers/counter/104-quad-8.c b/drivers/counter/104-quad-8.c
index 6e5286cd1d4e..4315b14f239e 100644
--- a/drivers/counter/104-quad-8.c
+++ b/drivers/counter/104-quad-8.c
@@ -52,7 +52,6 @@ MODULE_PARM_DESC(irq, "ACCES 104-QUAD-8 interrupt line numbers");
  */
 struct quad8 {
 	spinlock_t lock;
-	struct counter_device counter;
 	unsigned int fck_prescaler[QUAD8_NUM_COUNTERS];
 	unsigned int preset[QUAD8_NUM_COUNTERS];
 	unsigned int count_mode[QUAD8_NUM_COUNTERS];
@@ -1127,6 +1126,7 @@ static irqreturn_t quad8_irq_handler(int irq, void *private)
 
 static int quad8_probe(struct device *dev, unsigned int id)
 {
+	struct counter_device *counter;
 	struct quad8 *priv;
 	int i, j;
 	unsigned int base_offset;
@@ -1138,19 +1138,19 @@ static int quad8_probe(struct device *dev, unsigned int id)
 		return -EBUSY;
 	}
 
-	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
-	if (!priv)
+	counter = devm_counter_alloc(dev, sizeof(*priv));
+	if (!counter)
 		return -ENOMEM;
+	priv = counter_priv(counter);
 
 	/* Initialize Counter device and driver data */
-	priv->counter.name = dev_name(dev);
-	priv->counter.parent = dev;
-	priv->counter.ops = &quad8_ops;
-	priv->counter.counts = quad8_counts;
-	priv->counter.num_counts = ARRAY_SIZE(quad8_counts);
-	priv->counter.signals = quad8_signals;
-	priv->counter.num_signals = ARRAY_SIZE(quad8_signals);
-	priv->counter.priv = priv;
+	counter->name = dev_name(dev);
+	counter->parent = dev;
+	counter->ops = &quad8_ops;
+	counter->counts = quad8_counts;
+	counter->num_counts = ARRAY_SIZE(quad8_counts);
+	counter->signals = quad8_signals;
+	counter->num_signals = ARRAY_SIZE(quad8_signals);
 	priv->base = base[id];
 
 	spin_lock_init(&priv->lock);
@@ -1192,11 +1192,15 @@ static int quad8_probe(struct device *dev, unsigned int id)
 	outb(QUAD8_CHAN_OP_ENABLE_INTERRUPT_FUNC, base[id] + QUAD8_REG_CHAN_OP);
 
 	err = devm_request_irq(dev, irq[id], quad8_irq_handler, IRQF_SHARED,
-			       priv->counter.name, priv);
+			       counter->name, priv);
 	if (err)
 		return err;
 
-	return devm_counter_register(dev, &priv->counter);
+	err = devm_counter_add(dev, counter);
+	if (err < 0)
+		return dev_err_probe(dev, err, "Failed to add counter\n");
+
+	return 0;
 }
 
 static struct isa_driver quad8_driver = {
-- 
2.33.0