pwm: sprd: Simplify using devm_pwmchip_add() and dev_err_probe()

Using devm_pwmchip_add() allows to drop pwmchip_remove() from the remove
function which makes this function empty. Then there is no user of
drvdata left and platform_set_drvdata() can be dropped, too.

Further simplify and improve error returning using dev_err_probe().

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-sprd.c

···
 		chn->clk_rate = clk_get_rate(clk_pwm);
 	}
 
-	if (!i) {
-		dev_err(spc->dev, "no available PWM channels\n");
-		return -ENODEV;
-	}
+	if (!i)
+		return dev_err_probe(spc->dev, -ENODEV, "no available PWM channels\n");
 
 	spc->num_pwms = i;
 
···
 		return PTR_ERR(spc->base);
 
 	spc->dev = &pdev->dev;
-	platform_set_drvdata(pdev, spc);
 
 	ret = sprd_pwm_clk_init(spc);
 	if (ret)
···
 	spc->chip.ops = &sprd_pwm_ops;
 	spc->chip.npwm = spc->num_pwms;
 
-	ret = pwmchip_add(&spc->chip);
+	ret = devm_pwmchip_add(&pdev->dev, &spc->chip);
 	if (ret)
 		dev_err(&pdev->dev, "failed to add PWM chip\n");
 
 	return ret;
-}
-
-static void sprd_pwm_remove(struct platform_device *pdev)
-{
-	struct sprd_pwm_chip *spc = platform_get_drvdata(pdev);
-
-	pwmchip_remove(&spc->chip);
 }
 
 static const struct of_device_id sprd_pwm_of_match[] = {
···
 		.of_match_table = sprd_pwm_of_match,
 	},
 	.probe = sprd_pwm_probe,
-	.remove_new = sprd_pwm_remove,
 };
 
 module_platform_driver(sprd_pwm_driver);