net: dsa: qca8k: handle error with qca8k_read operation

qca8k_read can fail. Rework any user to handle error values and
correctly return.

Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/dsa/qca8k.c b/drivers/net/dsa/qca8k.c
index c983028..5eb4d13 100644 (file)
--- a/drivers/net/dsa/qca8k.c
+++ b/drivers/net/dsa/qca8k.c
@@ -231,8 +231,13 @@ static int
 qca8k_regmap_read(void *ctx, uint32_t reg, uint32_t *val)
 {
        struct qca8k_priv *priv = (struct qca8k_priv *)ctx;
+       int ret;
+
+       ret = qca8k_read(priv, reg);
+       if (ret < 0)
+               return ret;
 
-       *val = qca8k_read(priv, reg);
+       *val = ret;
 
        return 0;
 }
@@ -300,15 +305,20 @@ qca8k_busy_wait(struct qca8k_priv *priv, u32 reg, u32 mask)
        return ret;
 }
 
-static void
+static int
 qca8k_fdb_read(struct qca8k_priv *priv, struct qca8k_fdb *fdb)
 {
-       u32 reg[4];
+       u32 reg[4], val;
        int i;
 
        /* load the ARL table into an array */
-       for (i = 0; i < 4; i++)
-               reg[i] = qca8k_read(priv, QCA8K_REG_ATU_DATA0 + (i * 4));
+       for (i = 0; i < 4; i++) {
+               val = qca8k_read(priv, QCA8K_REG_ATU_DATA0 + (i * 4));
+               if (val < 0)
+                       return val;
+
+               reg[i] = val;
+       }
 
        /* vid - 83:72 */
        fdb->vid = (reg[2] >> QCA8K_ATU_VID_S) & QCA8K_ATU_VID_M;
@@ -323,6 +333,8 @@ qca8k_fdb_read(struct qca8k_priv *priv, struct qca8k_fdb *fdb)
        fdb->mac[3] = (reg[0] >> QCA8K_ATU_ADDR3_S) & 0xff;
        fdb->mac[4] = (reg[0] >> QCA8K_ATU_ADDR4_S) & 0xff;
        fdb->mac[5] = reg[0] & 0xff;
+
+       return 0;
 }
 
 static void
@@ -374,6 +386,8 @@ qca8k_fdb_access(struct qca8k_priv *priv, enum qca8k_fdb_cmd cmd, int port)
        /* Check for table full violation when adding an entry */
        if (cmd == QCA8K_FDB_LOAD) {
                reg = qca8k_read(priv, QCA8K_REG_ATU_FUNC);
+               if (reg < 0)
+                       return reg;
                if (reg & QCA8K_ATU_FUNC_FULL)
                        return -1;
        }
@@ -388,10 +402,10 @@ qca8k_fdb_next(struct qca8k_priv *priv, struct qca8k_fdb *fdb, int port)
 
        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)
+               return ret;
 
-       return ret;
+       return qca8k_fdb_read(priv, fdb);
 }
 
 static int
@@ -449,6 +463,8 @@ qca8k_vlan_access(struct qca8k_priv *priv, enum qca8k_vlan_cmd cmd, u16 vid)
        /* Check for table full violation when adding an entry */
        if (cmd == QCA8K_VLAN_LOAD) {
                reg = qca8k_read(priv, QCA8K_REG_VTU_FUNC1);
+               if (reg < 0)
+                       return reg;
                if (reg & QCA8K_VTU_FUNC1_FULL)
                        return -ENOMEM;
        }
@@ -475,6 +491,8 @@ qca8k_vlan_add(struct qca8k_priv *priv, u8 port, u16 vid, bool untagged)
                goto out;
 
        reg = qca8k_read(priv, QCA8K_REG_VTU_FUNC0);
+       if (reg < 0)
+               return reg;
        reg |= QCA8K_VTU_FUNC0_VALID | QCA8K_VTU_FUNC0_IVL_EN;
        reg &= ~(QCA8K_VTU_FUNC0_EG_MODE_MASK << QCA8K_VTU_FUNC0_EG_MODE_S(port));
        if (untagged)
@@ -506,6 +524,8 @@ qca8k_vlan_del(struct qca8k_priv *priv, u8 port, u16 vid)
                goto out;
 
        reg = qca8k_read(priv, QCA8K_REG_VTU_FUNC0);
+       if (reg < 0)
+               return reg;
        reg &= ~(3 << QCA8K_VTU_FUNC0_EG_MODE_S(port));
        reg |= QCA8K_VTU_FUNC0_EG_MODE_NOT <<
                        QCA8K_VTU_FUNC0_EG_MODE_S(port);
@@ -621,8 +641,11 @@ qca8k_mdio_read(struct qca8k_priv *priv, int port, u32 regnum)
                            QCA8K_MDIO_MASTER_BUSY))
                return -ETIMEDOUT;
 
-       val = (qca8k_read(priv, QCA8K_MDIO_MASTER_CTRL) &
-               QCA8K_MDIO_MASTER_DATA_MASK);
+       val = qca8k_read(priv, QCA8K_MDIO_MASTER_CTRL);
+       if (val < 0)
+               return val;
+
+       val &= QCA8K_MDIO_MASTER_DATA_MASK;
 
        return val;
 }
@@ -978,6 +1001,8 @@ qca8k_phylink_mac_link_state(struct dsa_switch *ds, int port,
        u32 reg;
 
        reg = qca8k_read(priv, QCA8K_REG_PORT_STATUS(port));
+       if (reg < 0)
+               return reg;
 
        state->link = !!(reg & QCA8K_PORT_STATUS_LINK_UP);
        state->an_complete = state->link;
@@ -1078,18 +1103,26 @@ qca8k_get_ethtool_stats(struct dsa_switch *ds, int port,
 {
        struct qca8k_priv *priv = (struct qca8k_priv *)ds->priv;
        const struct qca8k_mib_desc *mib;
-       u32 reg, i;
+       u32 reg, i, val;
        u64 hi;
 
        for (i = 0; i < ARRAY_SIZE(ar8327_mib); i++) {
                mib = &ar8327_mib[i];
                reg = QCA8K_PORT_MIB_COUNTER(port) + mib->offset;
 
-               data[i] = qca8k_read(priv, reg);
+               val = qca8k_read(priv, reg);
+               if (val < 0)
+                       continue;
+
                if (mib->size == 2) {
                        hi = qca8k_read(priv, reg + 4);
-                       data[i] |= hi << 32;
+                       if (hi < 0)
+                               continue;
                }
+
+               data[i] = val;
+               if (mib->size == 2)
+                       data[i] |= hi << 32;
        }
 }
 
@@ -1107,18 +1140,25 @@ qca8k_set_mac_eee(struct dsa_switch *ds, int port, struct ethtool_eee *eee)
 {
        struct qca8k_priv *priv = (struct qca8k_priv *)ds->priv;
        u32 lpi_en = QCA8K_REG_EEE_CTRL_LPI_EN(port);
+       int ret = 0;
        u32 reg;
 
        mutex_lock(&priv->reg_mutex);
        reg = qca8k_read(priv, QCA8K_REG_EEE_CTRL);
+       if (reg < 0) {
+               ret = reg;
+               goto exit;
+       }
+
        if (eee->eee_enabled)
                reg |= lpi_en;
        else
                reg &= ~lpi_en;
        qca8k_write(priv, QCA8K_REG_EEE_CTRL, reg);
-       mutex_unlock(&priv->reg_mutex);
 
-       return 0;
+exit:
+       mutex_unlock(&priv->reg_mutex);
+       return ret;
 }
 
 static int
@@ -1443,6 +1483,9 @@ qca8k_sw_probe(struct mdio_device *mdiodev)
 
        /* read the switches ID register */
        id = qca8k_read(priv, QCA8K_REG_MASK_CTRL);
+       if (id < 0)
+               return id;
+
        id >>= QCA8K_MASK_CTRL_ID_S;
        id &= QCA8K_MASK_CTRL_ID_M;
        if (id != QCA8K_ID_QCA8337)