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

Ansuel Smith
2021-05-04T22:29:41Z

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;
}

@@ -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();
} while (!time_after_eq(jiffies, timeout));
@@ -296,15 +303,20 @@ qca8k_busy_wait(struct qca8k_priv *priv, u32 reg, u32 mask)
return time_after_eq(jiffies, timeout);
}

-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;
@@ -319,6 +331,8 @@ 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
@@ -370,6 +384,8 @@ 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;
}
@@ -380,12 +396,15 @@ qca8k_fdb_access(struct qca8k_priv *priv, enum qca8k_fdb_cmd cmd, int port)
static int
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;
}
@@ -445,6 +464,8 @@ 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;
}
@@ -471,6 +492,8 @@ 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)
@@ -502,6 +525,8 @@ 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);
@@ -617,8 +642,11 @@ 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;
}
@@ -974,6 +1002,8 @@ 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;
@@ -1074,18 +1104,26 @@ 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;
}
}

@@ -1103,18 +1141,25 @@ 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
@@ -1439,6 +1484,9 @@ 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