mailbox: imx: support return value of init

There will be changes that init may fail, so adding return value for
init function.

Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Jassi Brar <jassisinghbrar@gmail.com>

drivers/mailbox/imx-mailbox.c

@@ -110,7 +110,7 @@ struct imx_mu_dcfg {
 	int (*tx)(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp, void *data);
 	int (*rx)(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp);
 	int (*rxdb)(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp);
-	void (*init)(struct imx_mu_priv *priv);
+	int (*init)(struct imx_mu_priv *priv);
 	enum imx_mu_type type;
 	u32	xTR;		/* Transmit Register0 */
 	u32	xRR;		/* Receive Register0 */
@@ -737,7 +737,7 @@ static struct mbox_chan *imx_mu_seco_xlate(struct mbox_controller *mbox,
 	return imx_mu_xlate(mbox, sp);
 }
 
-static void imx_mu_init_generic(struct imx_mu_priv *priv)
+static int imx_mu_init_generic(struct imx_mu_priv *priv)
 {
 	unsigned int i;
 	unsigned int val;
@@ -757,7 +757,7 @@ static void imx_mu_init_generic(struct imx_mu_priv *priv)
 	priv->mbox.of_xlate = imx_mu_xlate;
 
 	if (priv->side_b)
-		return;
+		return 0;
 
 	/* Set default MU configuration */
 	for (i = 0; i < IMX_MU_xCR_MAX; i++)
@@ -770,9 +770,11 @@ static void imx_mu_init_generic(struct imx_mu_priv *priv)
 	/* Clear any pending RSR */
 	for (i = 0; i < IMX_MU_NUM_RR; i++)
 		imx_mu_read(priv, priv->dcfg->xRR + (i % 4) * 4);
+
+	return 0;
 }
 
-static void imx_mu_init_specific(struct imx_mu_priv *priv)
+static int imx_mu_init_specific(struct imx_mu_priv *priv)
 {
 	unsigned int i;
 	int num_chans = priv->dcfg->type & IMX_MU_V2_S4 ? IMX_MU_S4_CHANS : IMX_MU_SCU_CHANS;
@@ -794,12 +796,20 @@ static void imx_mu_init_specific(struct imx_mu_priv *priv)
 	/* Set default MU configuration */
 	for (i = 0; i < IMX_MU_xCR_MAX; i++)
 		imx_mu_write(priv, 0, priv->dcfg->xCR[i]);
+
+	return 0;
 }
 
-static void imx_mu_init_seco(struct imx_mu_priv *priv)
+static int imx_mu_init_seco(struct imx_mu_priv *priv)
 {
-	imx_mu_init_generic(priv);
+	int ret;
+
+	ret = imx_mu_init_generic(priv);
+	if (ret)
+		return ret;
 	priv->mbox.of_xlate = imx_mu_seco_xlate;
+
+	return 0;
 }
 
 static int imx_mu_probe(struct platform_device *pdev)
@@ -866,7 +876,11 @@ static int imx_mu_probe(struct platform_device *pdev)
 
 	priv->side_b = of_property_read_bool(np, "fsl,mu-side-b");
 
-	priv->dcfg->init(priv);
+	ret = priv->dcfg->init(priv);
+	if (ret) {
+		dev_err(dev, "Failed to init MU\n");
+		goto disable_clk;
+	}
 
 	spin_lock_init(&priv->xcr_lock);
 
@@ -878,10 +892,8 @@ static int imx_mu_probe(struct platform_device *pdev)
 	platform_set_drvdata(pdev, priv);
 
 	ret = devm_mbox_controller_register(dev, &priv->mbox);
-	if (ret) {
-		clk_disable_unprepare(priv->clk);
-		return ret;
-	}
+	if (ret)
+		goto disable_clk;
 
 	pm_runtime_enable(dev);
 
@@ -899,6 +911,7 @@ static int imx_mu_probe(struct platform_device *pdev)
 
 disable_runtime_pm:
 	pm_runtime_disable(dev);
+disable_clk:
 	clk_disable_unprepare(priv->clk);
 	return ret;
 }