PM / devfreq: sun8i-a33-mbus: Simplify by using more devm functions

Use devm allocators for enabling the bus clock and
clk_rate_exclusive_get(). This simplifies error handling and the remove
callback.

Reviewed-by: Chen-Yu Tsai <[e-mail]>
Signed-off-by: Uwe Kleine-König <[e-mail]>
Tested-by: Corentin LABBE <[e-mail]>
Link: https://patchwork.kernel.org/project/linux-pm/patch/[e-mail]/
Signed-off-by: Chanwoo Choi <[e-mail]>

drivers/devfreq/sun8i-a33-mbus.c

···
 	if (IS_ERR(priv->reg_mbus))
 		return PTR_ERR(priv->reg_mbus);
 
-	priv->clk_bus = devm_clk_get(dev, "bus");
+	priv->clk_bus = devm_clk_get_enabled(dev, "bus");
 	if (IS_ERR(priv->clk_bus))
 		return dev_err_probe(dev, PTR_ERR(priv->clk_bus),
 				     "failed to get bus clock\n");
···
 		return dev_err_probe(dev, PTR_ERR(priv->clk_mbus),
 				     "failed to get mbus clock\n");
 
-	ret = clk_prepare_enable(priv->clk_bus);
-	if (ret)
-		return dev_err_probe(dev, ret,
-				     "failed to enable bus clock\n");
-
 	/* Lock the DRAM clock rate to keep priv->nominal_bw in sync. */
-	ret = clk_rate_exclusive_get(priv->clk_dram);
-	if (ret) {
-		err = "failed to lock dram clock rate\n";
-		goto err_disable_bus;
-	}
+	ret = devm_clk_rate_exclusive_get(dev, priv->clk_dram);
+	if (ret)
+		return dev_err_probe(dev, ret, "failed to lock dram clock rate\n");
 
 	/* Lock the MBUS clock rate to keep MBUS_TMR_PERIOD in sync. */
-	ret = clk_rate_exclusive_get(priv->clk_mbus);
-	if (ret) {
-		err = "failed to lock mbus clock rate\n";
-		goto err_unlock_dram;
-	}
+	ret = devm_clk_rate_exclusive_get(dev, priv->clk_mbus);
+	if (ret)
+		return dev_err_probe(dev, ret, "failed to lock mbus clock rate\n");
 
 	priv->gov_data.upthreshold	= 10;
 	priv->gov_data.downdifferential	=  5;
···
 	priv->profile.max_state		= max_state;
 
 	ret = devm_pm_opp_set_clkname(dev, "dram");
-	if (ret) {
-		err = "failed to add OPP table\n";
-		goto err_unlock_mbus;
-	}
+	if (ret)
+		return dev_err_probe(dev, ret, "failed to add OPP table\n");
 
 	base_freq = clk_get_rate(clk_get_parent(priv->clk_dram));
 	for (i = 0; i < max_state; ++i) {
···
 
 err_remove_opps:
 	dev_pm_opp_remove_all_dynamic(dev);
-err_unlock_mbus:
-	clk_rate_exclusive_put(priv->clk_mbus);
-err_unlock_dram:
-	clk_rate_exclusive_put(priv->clk_dram);
-err_disable_bus:
-	clk_disable_unprepare(priv->clk_bus);
 
 	return dev_err_probe(dev, ret, err);
 }
···
 		dev_warn(dev, "failed to restore DRAM frequency: %d\n", ret);
 
 	dev_pm_opp_remove_all_dynamic(dev);
-	clk_rate_exclusive_put(priv->clk_mbus);
-	clk_rate_exclusive_put(priv->clk_dram);
-	clk_disable_unprepare(priv->clk_bus);
 }
 
 static const struct sun8i_a33_mbus_variant sun50i_a64_mbus = {