Thread (59 messages) flat view 59 messages, 6 authors, 2021-05-08

Re: [RFC PATCH net-next v3 05/20] net: dsa: qca8k: handle error with qca8k_read operation

From: Andrew Lunn <andrew@lunn.ch>
Date: 2021-05-05 00:36:23
Also in: lkml

On Wed, May 05, 2021 at 12:28:59AM +0200, Ansuel Smith wrote:
quoted hunk ↗ jump to hunk
qca8k_read can fail. Rework any user to handle error values and
correctly return.

Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
---
 drivers/net/dsa/qca8k.c | 90 +++++++++++++++++++++++++++++++----------
 1 file changed, 69 insertions(+), 21 deletions(-)
diff --git a/drivers/net/dsa/qca8k.c b/drivers/net/dsa/qca8k.c
index 411b42d38819..cde68ed6856b 100644
--- a/drivers/net/dsa/qca8k.c
+++ b/drivers/net/dsa/qca8k.c
@@ -146,12 +146,13 @@ qca8k_set_page(struct mii_bus *bus, u16 page)
 static u32
 qca8k_read(struct qca8k_priv *priv, u32 reg)
 {
+	struct mii_bus *bus = priv->bus;
 	u16 r1, r2, page;
 	u32 val;
 
 	qca8k_split_addr(reg, &r1, &r2, &page);
 
-	mutex_lock_nested(&priv->bus->mdio_lock, MDIO_MUTEX_NESTED);
+	mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED);
 
 	val = qca8k_set_page(priv->bus, page);
 	if (val < 0)
@@ -160,8 +161,7 @@ qca8k_read(struct qca8k_priv *priv, u32 reg)
 	val = qca8k_mii_read32(priv->bus, 0x10 | r2, r1);
 
 exit:
-	mutex_unlock(&priv->bus->mdio_lock);
-
+	mutex_unlock(&bus->mdio_lock);
 	return val;
This change does not have anything to do with the commit message.
quoted hunk ↗ jump to hunk
 }
 
@@ -226,8 +226,13 @@ static int
 qca8k_regmap_read(void *ctx, uint32_t reg, uint32_t *val)
 {
 	struct qca8k_priv *priv = (struct qca8k_priv *)ctx;
+	int ret;
 
-	*val = qca8k_read(priv, reg);
+	ret = qca8k_read(priv, reg);
+	if (ret < 0)
+		return ret;
+
+	*val = ret;
 
 	return 0;
 }
@@ -280,15 +285,17 @@ static int
 qca8k_busy_wait(struct qca8k_priv *priv, u32 reg, u32 mask)
 {
 	unsigned long timeout;
+	u32 val;
 
 	timeout = jiffies + msecs_to_jiffies(20);
 
 	/* loop until the busy flag has cleared */
 	do {
-		u32 val = qca8k_read(priv, reg);
-		int busy = val & mask;
+		val = qca8k_read(priv, reg);
+		if (val < 0)
+			continue;
 
-		if (!busy)
+		if (!(val & mask))
 			break;
 		cond_resched();
Maybe there is a patch doing this already, but it would be good to
make use of include/linux/iopoll.h
 qca8k_fdb_next(struct qca8k_priv *priv, struct qca8k_fdb *fdb, int port)
 {
-	int ret;
+	int ret, ret_read;
 
 	qca8k_fdb_write(priv, fdb->vid, fdb->port_mask, fdb->mac, fdb->aging);
 	ret = qca8k_fdb_access(priv, QCA8K_FDB_NEXT, port);
-	if (ret >= 0)
-		qca8k_fdb_read(priv, fdb);
+	if (ret >= 0) {
+		ret_read = qca8k_fdb_read(priv, fdb);
+		if (ret_read < 0)
+			return ret_read;
+	}
 
 	return ret;
 }
This is oddly structured. Why not:

qca8k_fdb_next(struct qca8k_priv *priv, struct qca8k_fdb *fdb, int port)
{
	int ret;

	qca8k_fdb_write(priv, fdb->vid, fdb->port_mask, fdb->mac, fdb->aging);

	ret = qca8k_fdb_access(priv, QCA8K_FDB_NEXT, port);
	if (ret < 0)
		return ret;

	return qca8k_fdb_read(priv, fdb);
}

	Andrew
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