can: rcar_canfd: Improve error messages

Improve printed error messages:
  - Replace numerical error codes by mnemotechnic error codes, to
    improve the user experience in case of errors,
  - Drop parentheses around printed numbers, cfr.
    Documentation/process/coding-style.rst,
  - Drop printing of an error message in case of out-of-memory, as the
    core memory allocation code already takes care of this.
Suggested-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/all/4162cc46f72257ec191007675933985b6df394b9.1679414936.git.geert+renesas@glider.be
[mkl: use colon instead of comma]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

drivers/net/can/rcar/rcar_canfd.c

@@ -1424,13 +1424,13 @@ static int rcar_canfd_open(struct net_device *ndev)
 	/* Peripheral clock is already enabled in probe */
 	err = clk_prepare_enable(gpriv->can_clk);
 	if (err) {
-		netdev_err(ndev, "failed to enable CAN clock, error %d\n", err);
+		netdev_err(ndev, "failed to enable CAN clock: %pe\n", ERR_PTR(err));
 		goto out_phy;
 	}
 
 	err = open_candev(ndev);
 	if (err) {
-		netdev_err(ndev, "open_candev() failed, error %d\n", err);
+		netdev_err(ndev, "open_candev() failed: %pe\n", ERR_PTR(err));
 		goto out_can_clock;
 	}
 
@@ -1731,10 +1731,9 @@ static int rcar_canfd_channel_probe(struct rcar_canfd_global *gpriv, u32 ch,
 	int err = -ENODEV;
 
 	ndev = alloc_candev(sizeof(*priv), RCANFD_FIFO_DEPTH);
-	if (!ndev) {
-		dev_err(dev, "alloc_candev() failed\n");
+	if (!ndev)
 		return -ENOMEM;
-	}
+
 	priv = netdev_priv(ndev);
 
 	ndev->netdev_ops = &rcar_canfd_netdev_ops;
@@ -1777,8 +1776,8 @@ static int rcar_canfd_channel_probe(struct rcar_canfd_global *gpriv, u32 ch,
 				       rcar_canfd_channel_err_interrupt, 0,
 				       irq_name, priv);
 		if (err) {
-			dev_err(dev, "devm_request_irq CH Err(%d) failed, error %d\n",
-				err_irq, err);
+			dev_err(dev, "devm_request_irq CH Err %d failed: %pe\n",
+				err_irq, ERR_PTR(err));
 			goto fail;
 		}
 		irq_name = devm_kasprintf(dev, GFP_KERNEL, "canfd.ch%d_trx",
@@ -1791,8 +1790,8 @@ static int rcar_canfd_channel_probe(struct rcar_canfd_global *gpriv, u32 ch,
 				       rcar_canfd_channel_tx_interrupt, 0,
 				       irq_name, priv);
 		if (err) {
-			dev_err(dev, "devm_request_irq Tx (%d) failed, error %d\n",
-				tx_irq, err);
+			dev_err(dev, "devm_request_irq Tx %d failed: %pe\n",
+				tx_irq, ERR_PTR(err));
 			goto fail;
 		}
 	}
@@ -1823,7 +1822,7 @@ static int rcar_canfd_channel_probe(struct rcar_canfd_global *gpriv, u32 ch,
 	gpriv->ch[priv->channel] = priv;
 	err = register_candev(ndev);
 	if (err) {
-		dev_err(dev, "register_candev() failed, error %d\n", err);
+		dev_err(dev, "register_candev() failed: %pe\n", ERR_PTR(err));
 		goto fail_candev;
 	}
 	dev_info(dev, "device registered (channel %u)\n", priv->channel);
@@ -1967,16 +1966,16 @@ static int rcar_canfd_probe(struct platform_device *pdev)
 				       rcar_canfd_channel_interrupt, 0,
 				       "canfd.ch_int", gpriv);
 		if (err) {
-			dev_err(dev, "devm_request_irq(%d) failed, error %d\n",
-				ch_irq, err);
+			dev_err(dev, "devm_request_irq %d failed: %pe\n",
+				ch_irq, ERR_PTR(err));
 			goto fail_dev;
 		}
 
 		err = devm_request_irq(dev, g_irq, rcar_canfd_global_interrupt,
 				       0, "canfd.g_int", gpriv);
 		if (err) {
-			dev_err(dev, "devm_request_irq(%d) failed, error %d\n",
-				g_irq, err);
+			dev_err(dev, "devm_request_irq %d failed: %pe\n",
+				g_irq, ERR_PTR(err));
 			goto fail_dev;
 		}
 	} else {
@@ -1985,8 +1984,8 @@ static int rcar_canfd_probe(struct platform_device *pdev)
 				       "canfd.g_recc", gpriv);
 
 		if (err) {
-			dev_err(dev, "devm_request_irq(%d) failed, error %d\n",
-				g_recc_irq, err);
+			dev_err(dev, "devm_request_irq %d failed: %pe\n",
+				g_recc_irq, ERR_PTR(err));
 			goto fail_dev;
 		}
 
@@ -1994,8 +1993,8 @@ static int rcar_canfd_probe(struct platform_device *pdev)
 				       rcar_canfd_global_err_interrupt, 0,
 				       "canfd.g_err", gpriv);
 		if (err) {
-			dev_err(dev, "devm_request_irq(%d) failed, error %d\n",
-				g_err_irq, err);
+			dev_err(dev, "devm_request_irq %d failed: %pe\n",
+				g_err_irq, ERR_PTR(err));
 			goto fail_dev;
 		}
 	}
@@ -2012,14 +2011,14 @@ static int rcar_canfd_probe(struct platform_device *pdev)
 	/* Enable peripheral clock for register access */
 	err = clk_prepare_enable(gpriv->clkp);
 	if (err) {
-		dev_err(dev, "failed to enable peripheral clock, error %d\n",
-			err);
+		dev_err(dev, "failed to enable peripheral clock: %pe\n",
+			ERR_PTR(err));
 		goto fail_reset;
 	}
 
 	err = rcar_canfd_reset_controller(gpriv);
 	if (err) {
-		dev_err(dev, "reset controller failed\n");
+		dev_err(dev, "reset controller failed: %pe\n", ERR_PTR(err));
 		goto fail_clk;
 	}