[RFC PATCH net-next v3 04/20] net: dsa: qca8k: handle qca8k_set_page errors
From: Ansuel Smith <ansuelsmth@gmail.com>
Date: 2021-05-04 22:29:47
Also in:
lkml
Subsystem:
networking drivers, networking [dsa], the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Andrew Lunn, Vladimir Oltean, Linus Torvalds
With a remote possibility, the set_page function can fail. Since this is a critical part of the write/read qca8k regs, propagate the error and terminate any read/write operation. Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com> --- drivers/net/dsa/qca8k.c | 29 +++++++++++++++++++++++------ 1 file changed, 23 insertions(+), 6 deletions(-)
diff --git a/drivers/net/dsa/qca8k.c b/drivers/net/dsa/qca8k.c
index cdaf9f85a2cb..411b42d38819 100644
--- a/drivers/net/dsa/qca8k.c
+++ b/drivers/net/dsa/qca8k.c@@ -127,16 +127,20 @@ qca8k_mii_write32(struct mii_bus *bus, int phy_id, u32 regnum, u32 val) "failed to write qca8k 32bit register\n"); } -static void +static int qca8k_set_page(struct mii_bus *bus, u16 page) { if (page == qca8k_current_page) - return; + return 0; - if (bus->write(bus, 0x18, 0, page) < 0) + if (bus->write(bus, 0x18, 0, page) < 0) { dev_err_ratelimited(&bus->dev, "failed to set qca8k page\n"); + return -EBUSY; + } + qca8k_current_page = page; + return 0; } static u32
@@ -149,9 +153,13 @@ qca8k_read(struct qca8k_priv *priv, u32 reg) mutex_lock_nested(&priv->bus->mdio_lock, MDIO_MUTEX_NESTED); - qca8k_set_page(priv->bus, page); + val = qca8k_set_page(priv->bus, page); + if (val < 0) + goto exit; + val = qca8k_mii_read32(priv->bus, 0x10 | r2, r1); +exit: mutex_unlock(&priv->bus->mdio_lock); return val;
@@ -161,14 +169,19 @@ static void qca8k_write(struct qca8k_priv *priv, u32 reg, u32 val) { u16 r1, r2, page; + int ret; qca8k_split_addr(reg, &r1, &r2, &page); mutex_lock_nested(&priv->bus->mdio_lock, MDIO_MUTEX_NESTED); - qca8k_set_page(priv->bus, page); + ret = qca8k_set_page(priv->bus, page); + if (ret < 0) + goto exit; + qca8k_mii_write32(priv->bus, 0x10 | r2, r1, val); +exit: mutex_unlock(&priv->bus->mdio_lock); }
@@ -182,12 +195,16 @@ qca8k_rmw(struct qca8k_priv *priv, u32 reg, u32 mask, u32 val) mutex_lock_nested(&priv->bus->mdio_lock, MDIO_MUTEX_NESTED); - qca8k_set_page(priv->bus, page); + ret = qca8k_set_page(priv->bus, page); + if (ret < 0) + goto exit; + ret = qca8k_mii_read32(priv->bus, 0x10 | r2, r1); ret &= ~mask; ret |= val; qca8k_mii_write32(priv->bus, 0x10 | r2, r1, ret); +exit: mutex_unlock(&priv->bus->mdio_lock); return ret;
--
2.30.2