counter: ti-eqep: Convert to new counter registration

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

Fixes: f213729 ("counter: new TI eQEP driver")
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Acked-by: David Lechner <david@lechnology.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20211230150300.72196-23-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: Uwe Kleine-König

drivers/counter/ti-eqep.c

@@ -373,13 +373,15 @@ static const struct regmap_config ti_eqep_regmap16_config = {
 static int ti_eqep_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
+	struct counter_device *counter;
 	struct ti_eqep_cnt *priv;
 	void __iomem *base;
 	int err;
 
-	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);
 
 	base = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(base))
@@ -395,16 +397,15 @@ static int ti_eqep_probe(struct platform_device *pdev)
 	if (IS_ERR(priv->regmap16))
 		return PTR_ERR(priv->regmap16);
 
-	priv->counter.name = dev_name(dev);
-	priv->counter.parent = dev;
-	priv->counter.ops = &ti_eqep_counter_ops;
-	priv->counter.counts = ti_eqep_counts;
-	priv->counter.num_counts = ARRAY_SIZE(ti_eqep_counts);
-	priv->counter.signals = ti_eqep_signals;
-	priv->counter.num_signals = ARRAY_SIZE(ti_eqep_signals);
-	priv->counter.priv = priv;
+	counter->name = dev_name(dev);
+	counter->parent = dev;
+	counter->ops = &ti_eqep_counter_ops;
+	counter->counts = ti_eqep_counts;
+	counter->num_counts = ARRAY_SIZE(ti_eqep_counts);
+	counter->signals = ti_eqep_signals;
+	counter->num_signals = ARRAY_SIZE(ti_eqep_signals);
 
-	platform_set_drvdata(pdev, priv);
+	platform_set_drvdata(pdev, counter);
 
 	/*
 	 * Need to make sure power is turned on. On AM33xx, this comes from the
@@ -414,7 +415,7 @@ static int ti_eqep_probe(struct platform_device *pdev)
 	pm_runtime_enable(dev);
 	pm_runtime_get_sync(dev);
 
-	err = counter_register(&priv->counter);
+	err = counter_add(counter);
 	if (err < 0) {
 		pm_runtime_put_sync(dev);
 		pm_runtime_disable(dev);
@@ -426,10 +427,10 @@ static int ti_eqep_probe(struct platform_device *pdev)
 
 static int ti_eqep_remove(struct platform_device *pdev)
 {
-	struct ti_eqep_cnt *priv = platform_get_drvdata(pdev);
+	struct counter_device *counter = platform_get_drvdata(pdev);
 	struct device *dev = &pdev->dev;
 
-	counter_unregister(&priv->counter);
+	counter_unregister(counter);
 	pm_runtime_put_sync(dev);
 	pm_runtime_disable(dev);