pwm: atmel-tcb: Harmonize resource allocation order

[ Upstream commit 0323e8f ]

Allocate driver data as first resource in the probe function. This way it
can be used during allocation of the other resources (instead of assigning
these to local variables first and update driver data only when it's
allocated). Also as driver data is allocated using a devm function this
should happen first to have the order of freeing resources in the error
path and the remove function in reverse.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Stable-dep-of: c116223 ("pwm: atmel-tcb: Fix resource freeing in error path and remove")
Signed-off-by: Sasha Levin <sashal@kernel.org>

drivers/pwm/pwm-atmel-tcb.c

@@ -422,13 +422,14 @@ static int atmel_tcb_pwm_probe(struct platform_device *pdev)
 	struct atmel_tcb_pwm_chip *tcbpwm;
 	const struct atmel_tcb_config *config;
 	struct device_node *np = pdev->dev.of_node;
-	struct regmap *regmap;
-	struct clk *clk, *gclk = NULL;
-	struct clk *slow_clk;
 	char clk_name[] = "t0_clk";
 	int err;
 	int channel;
 
+	tcbpwm = devm_kzalloc(&pdev->dev, sizeof(*tcbpwm), GFP_KERNEL);
+	if (tcbpwm == NULL)
+		return -ENOMEM;
+
 	err = of_property_read_u32(np, "reg", &channel);
 	if (err < 0) {
 		dev_err(&pdev->dev,
@@ -437,47 +438,37 @@ static int atmel_tcb_pwm_probe(struct platform_device *pdev)
 		return err;
 	}
 
-	regmap = syscon_node_to_regmap(np->parent);
-	if (IS_ERR(regmap))
-		return PTR_ERR(regmap);
+	tcbpwm->regmap = syscon_node_to_regmap(np->parent);
+	if (IS_ERR(tcbpwm->regmap))
+		return PTR_ERR(tcbpwm->regmap);
 
-	slow_clk = of_clk_get_by_name(np->parent, "slow_clk");
-	if (IS_ERR(slow_clk))
-		return PTR_ERR(slow_clk);
+	tcbpwm->slow_clk = of_clk_get_by_name(np->parent, "slow_clk");
+	if (IS_ERR(tcbpwm->slow_clk))
+		return PTR_ERR(tcbpwm->slow_clk);
 
 	clk_name[1] += channel;
-	clk = of_clk_get_by_name(np->parent, clk_name);
-	if (IS_ERR(clk))
-		clk = of_clk_get_by_name(np->parent, "t0_clk");
-	if (IS_ERR(clk))
-		return PTR_ERR(clk);
+	tcbpwm->clk = of_clk_get_by_name(np->parent, clk_name);
+	if (IS_ERR(tcbpwm->clk))
+		tcbpwm->clk = of_clk_get_by_name(np->parent, "t0_clk");
+	if (IS_ERR(tcbpwm->clk))
+		return PTR_ERR(tcbpwm->clk);
 
 	match = of_match_node(atmel_tcb_of_match, np->parent);
 	config = match->data;
 
 	if (config->has_gclk) {
-		gclk = of_clk_get_by_name(np->parent, "gclk");
-		if (IS_ERR(gclk))
-			return PTR_ERR(gclk);
-	}
-
-	tcbpwm = devm_kzalloc(&pdev->dev, sizeof(*tcbpwm), GFP_KERNEL);
-	if (tcbpwm == NULL) {
-		err = -ENOMEM;
-		goto err_slow_clk;
+		tcbpwm->gclk = of_clk_get_by_name(np->parent, "gclk");
+		if (IS_ERR(tcbpwm->gclk))
+			return PTR_ERR(tcbpwm->gclk);
 	}
 
 	tcbpwm->chip.dev = &pdev->dev;
 	tcbpwm->chip.ops = &atmel_tcb_pwm_ops;
 	tcbpwm->chip.npwm = NPWM;
 	tcbpwm->channel = channel;
-	tcbpwm->regmap = regmap;
-	tcbpwm->clk = clk;
-	tcbpwm->gclk = gclk;
-	tcbpwm->slow_clk = slow_clk;
 	tcbpwm->width = config->counter_width;
 
-	err = clk_prepare_enable(slow_clk);
+	err = clk_prepare_enable(tcbpwm->slow_clk);
 	if (err)
 		goto err_slow_clk;
 
@@ -495,7 +486,7 @@ static int atmel_tcb_pwm_probe(struct platform_device *pdev)
 	clk_disable_unprepare(tcbpwm->slow_clk);
 
 err_slow_clk:
-	clk_put(slow_clk);
+	clk_put(tcbpwm->slow_clk);
 
 	return err;
 }