pwm: renesas-tpu: Fix late Runtime PM enablement

BugLink: https://bugs.launchpad.net/bugs/1878098

[ Upstream commit d5a3c7a4 ]

Runtime PM should be enabled before calling pwmchip_add(), as PWM users
can appear immediately after the PWM chip has been added.
Likewise, Runtime PM should always be disabled after the removal of the
PWM chip, even if the latter failed.

Fixes: 99b82abb ("pwm: Add Renesas TPU PWM driver")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Ian May <ian.may@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>

drivers/pwm/pwm-renesas-tpu.c

@@ -423,16 +423,17 @@ static int tpu_probe(struct platform_device *pdev)
 	tpu->chip.base = -1;
 	tpu->chip.npwm = TPU_CHANNEL_MAX;
 
+	pm_runtime_enable(&pdev->dev);
+
 	ret = pwmchip_add(&tpu->chip);
 	if (ret < 0) {
 		dev_err(&pdev->dev, "failed to register PWM chip\n");
+		pm_runtime_disable(&pdev->dev);
 		return ret;
 	}
 
 	dev_info(&pdev->dev, "TPU PWM %d registered\n", tpu->pdev->id);
 
-	pm_runtime_enable(&pdev->dev);
-
 	return 0;
 }
 
@@ -442,12 +443,10 @@ static int tpu_remove(struct platform_device *pdev)
 	int ret;
 
 	ret = pwmchip_remove(&tpu->chip);
-	if (ret)
-		return ret;
 
 	pm_runtime_disable(&pdev->dev);
 
-	return 0;
+	return ret;
 }
 
 #ifdef CONFIG_OF