netdev - [PATCH] net: ftgmac100: reduce calls to of_device_is

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Message-ID: <20260110022827.2067386-1-daniel@thingy.jp>
Date: Sat, 10 Jan 2026 11:28:27 +0900
From: Daniel Palmer <daniel@...ngy.jp>
To: andrew+netdev@...n.ch,
	davem@...emloft.net,
	edumazet@...gle.com,
	kuba@...nel.org,
	pabeni@...hat.com,
	jacky_chou@...eedtech.com,
	netdev@...r.kernel.org
Cc: linux-kernel@...r.kernel.org,
	Daniel Palmer <daniel@...ngy.jp>
Subject: [PATCH] net: ftgmac100: reduce calls to of_device_is_compatible()

ftgmac100_probe() calls of_device_is_compatible() with the same arguments
multiple times.

Just call of_device_is_compatible() once for each variant, save the result
into a local variable and use the variable instead.

Signed-off-by: Daniel Palmer <daniel@...ngy.jp>
---

I am looking through callers to of_device_is_compatible() and noticed this.
I have build tested but I don't have this hardware so I haven't tested if
it works or not. I don't see why it wouldn't. This only saves 8 bytes of code
in my build so its not massive but I think the code makes more sense after
this.

 drivers/net/ethernet/faraday/ftgmac100.c | 25 ++++++++++++++----------
 1 file changed, 15 insertions(+), 10 deletions(-)

diff --git a/drivers/net/ethernet/faraday/ftgmac100.c b/drivers/net/ethernet/faraday/ftgmac100.c
index a863f7841210..1588d3c79ddf 100644
--- a/drivers/net/ethernet/faraday/ftgmac100.c
+++ b/drivers/net/ethernet/faraday/ftgmac100.c
@@ -1840,7 +1840,10 @@ static int ftgmac100_probe(struct platform_device *pdev)
 	struct net_device *netdev;
 	struct phy_device *phydev;
 	struct ftgmac100 *priv;
-	struct device_node *np;
+	struct device_node *np = pdev->dev.of_node;
+	bool is_ast2400 = false;
+	bool is_ast2500 = false;
+	bool is_ast2600 = false;
 	int err = 0;
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -1900,10 +1903,13 @@ static int ftgmac100_probe(struct platform_device *pdev)
 	if (err)
 		goto err_phy_connect;
 
-	np = pdev->dev.of_node;
-	if (np && (of_device_is_compatible(np, "aspeed,ast2400-mac") ||
-		   of_device_is_compatible(np, "aspeed,ast2500-mac") ||
-		   of_device_is_compatible(np, "aspeed,ast2600-mac"))) {
+	if (np) {
+		is_ast2400 = of_device_is_compatible(np, "aspeed,ast2400-mac");
+		is_ast2500 = !is_ast2400 && of_device_is_compatible(np, "aspeed,ast2500-mac");
+		is_ast2600 = !is_ast2500 && of_device_is_compatible(np, "aspeed,ast2600-mac");
+	}
+
+	if (is_ast2400 || is_ast2500 || is_ast2600) {
 		priv->rxdes0_edorr_mask = BIT(30);
 		priv->txdes0_edotr_mask = BIT(30);
 		priv->is_aspeed = true;
@@ -1948,8 +1954,7 @@ static int ftgmac100_probe(struct platform_device *pdev)
 		 * available PHYs and register them.
 		 */
 		if (of_get_property(np, "phy-handle", NULL) &&
-		    (of_device_is_compatible(np, "aspeed,ast2400-mac") ||
-		     of_device_is_compatible(np, "aspeed,ast2500-mac"))) {
+		    (is_ast2400 || is_ast2500)) {
 			err = ftgmac100_setup_mdio(netdev);
 			if (err)
 				goto err_setup_mdio;
@@ -2001,7 +2006,7 @@ static int ftgmac100_probe(struct platform_device *pdev)
 			goto err_phy_connect;
 
 		/* Disable ast2600 problematic HW arbitration */
-		if (of_device_is_compatible(np, "aspeed,ast2600-mac"))
+		if (is_ast2600)
 			iowrite32(FTGMAC100_TM_DEFAULT,
 				  priv->base + FTGMAC100_OFFSET_TM);
 	}
@@ -2019,11 +2024,11 @@ static int ftgmac100_probe(struct platform_device *pdev)
 		netdev->hw_features |= NETIF_F_HW_VLAN_CTAG_FILTER;
 
 	/* AST2400  doesn't have working HW checksum generation */
-	if (np && (of_device_is_compatible(np, "aspeed,ast2400-mac")))
+	if (is_ast2400)
 		netdev->hw_features &= ~NETIF_F_HW_CSUM;
 
 	/* AST2600 tx checksum with NCSI is broken */
-	if (priv->use_ncsi && of_device_is_compatible(np, "aspeed,ast2600-mac"))
+	if (priv->use_ncsi && is_ast2600)
 		netdev->hw_features &= ~NETIF_F_HW_CSUM;
 
 	if (np && of_get_property(np, "no-hw-checksum", NULL))
-- 
2.51.0