pwm: vt8500: Simplify using devm functions

With devm_clk_get_prepared() the call to clk_unprepare() can be dropped
from the error path and the remove callback. With devm_pwmchip_add()
pwmchip_remove() can be dropped. Then the remove callback is empty and
can go away, too. With vt8500_pwm_remove() the last user of
platform_get_drvdata() is gone and so platform_set_drvdata() can be
dropped, too.

Also use dev_err_probe() for simplified (and improved) error reporting.

Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Uwe Kleine-König <[e-mail]>
Signed-off-by: Thierry Reding <[e-mail]>

drivers/pwm/pwm-vt8500.c

···
 	struct device_node *np = pdev->dev.of_node;
 	int ret;
 
-	if (!np) {
-		dev_err(&pdev->dev, "invalid devicetree node\n");
-		return -EINVAL;
-	}
+	if (!np)
+		return dev_err_probe(&pdev->dev, -EINVAL, "invalid devicetree node\n");
 
 	vt8500 = devm_kzalloc(&pdev->dev, sizeof(*vt8500), GFP_KERNEL);
 	if (vt8500 == NULL)
···
 	vt8500->chip.ops = &vt8500_pwm_ops;
 	vt8500->chip.npwm = VT8500_NR_PWMS;
 
-	vt8500->clk = devm_clk_get(&pdev->dev, NULL);
-	if (IS_ERR(vt8500->clk)) {
-		dev_err(&pdev->dev, "clock source not specified\n");
-		return PTR_ERR(vt8500->clk);
-	}
+	vt8500->clk = devm_clk_get_prepared(&pdev->dev, NULL);
+	if (IS_ERR(vt8500->clk))
+		return dev_err_probe(&pdev->dev, PTR_ERR(vt8500->clk), "clock source not specified\n");
 
 	vt8500->base = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(vt8500->base))
 		return PTR_ERR(vt8500->base);
 
-	ret = clk_prepare(vt8500->clk);
-	if (ret < 0) {
-		dev_err(&pdev->dev, "failed to prepare clock\n");
-		return ret;
-	}
+	ret = devm_pwmchip_add(&pdev->dev, &vt8500->chip);
+	if (ret < 0)
+		return dev_err_probe(&pdev->dev, ret, "failed to add PWM chip\n");
 
-	ret = pwmchip_add(&vt8500->chip);
-	if (ret < 0) {
-		dev_err(&pdev->dev, "failed to add PWM chip\n");
-		clk_unprepare(vt8500->clk);
-		return ret;
-	}
-
-	platform_set_drvdata(pdev, vt8500);
-	return ret;
-}
-
-static void vt8500_pwm_remove(struct platform_device *pdev)
-{
-	struct vt8500_chip *vt8500 = platform_get_drvdata(pdev);
-
-	pwmchip_remove(&vt8500->chip);
-
-	clk_unprepare(vt8500->clk);
+	return 0;
 }
 
 static struct platform_driver vt8500_pwm_driver = {
 	.probe		= vt8500_pwm_probe,
-	.remove_new	= vt8500_pwm_remove,
 	.driver		= {
 		.name	= "vt8500-pwm",
 		.of_match_table = vt8500_pwm_dt_ids,