[RFC PATCH net-next v5 05/25] net: dsa: qca8k: handle error with qca8k_read operation

From: Ansuel Smith
Date: Mon May 10 2021 - 22:08:25 EST


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

Signed-off-by: Ansuel Smith <ansuelsmth@xxxxxxxxx>
Reviewed-by: Andrew Lunn <andrew@xxxxxxx>
---
drivers/net/dsa/qca8k.c | 73 ++++++++++++++++++++++++++++++++---------
1 file changed, 58 insertions(+), 15 deletions(-)

diff --git a/drivers/net/dsa/qca8k.c b/drivers/net/dsa/qca8k.c
index c9830286fd6d..5eb4d13fe0ba 100644
--- 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)
--
2.30.2