target/linux/generic/backport-5.10/739-v5.15-net-dsa-qca8k-fix-kernel-panic-with-legacy-mdio-mapping.patch

   1 From ce062a0adbfe933b1932235fdfd874c4c91d1bb0 Mon Sep 17 00:00:00 2001
   2 From: Ansuel Smith <ansuelsmth@gmail.com>
   3 Date: Sat, 11 Sep 2021 17:50:09 +0200
   4 Subject: net: dsa: qca8k: fix kernel panic with legacy mdio mapping
   5
   6 When the mdio legacy mapping is used the mii_bus priv registered by DSA
   7 refer to the dsa switch struct instead of the qca8k_priv struct and
   8 causes a kernel panic. Create dedicated function when the internal
   9 dedicated mdio driver is used to properly handle the 2 different
  10 implementation.
  11
  12 Fixes: 759bafb8a322 ("net: dsa: qca8k: add support for internal phy and internal mdio")
  13 Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
  14 Signed-off-by: David S. Miller <davem@davemloft.net>
  15 ---
  16  drivers/net/dsa/qca8k.c | 30 ++++++++++++++++++++++--------
  17  1 file changed, 22 insertions(+), 8 deletions(-)
  18
  19 --- a/drivers/net/dsa/qca8k.c
  20 +++ b/drivers/net/dsa/qca8k.c
  21 @@ -643,10 +643,8 @@ qca8k_mdio_busy_wait(struct mii_bus *bus
  22  }
  23
  24  static int
  25 -qca8k_mdio_write(struct mii_bus *salve_bus, int phy, int regnum, u16 data)
  26 +qca8k_mdio_write(struct mii_bus *bus, int phy, int regnum, u16 data)
  27  {
  28 -       struct qca8k_priv *priv = salve_bus->priv;
  29 -       struct mii_bus *bus = priv->bus;
  30         u16 r1, r2, page;
  31         u32 val;
  32         int ret;
  33 @@ -682,10 +680,8 @@ exit:
  34  }
  35
  36  static int
  37 -qca8k_mdio_read(struct mii_bus *salve_bus, int phy, int regnum)
  38 +qca8k_mdio_read(struct mii_bus *bus, int phy, int regnum)
  39  {
  40 -       struct qca8k_priv *priv = salve_bus->priv;
  41 -       struct mii_bus *bus = priv->bus;
  42         u16 r1, r2, page;
  43         u32 val;
  44         int ret;
  45 @@ -727,6 +723,24 @@ exit:
  46  }
  47
  48  static int
  49 +qca8k_internal_mdio_write(struct mii_bus *slave_bus, int phy, int regnum, u16 data)
  50 +{
  51 +       struct qca8k_priv *priv = slave_bus->priv;
  52 +       struct mii_bus *bus = priv->bus;
  53 +
  54 +       return qca8k_mdio_write(bus, phy, regnum, data);
  55 +}
  56 +
  57 +static int
  58 +qca8k_internal_mdio_read(struct mii_bus *slave_bus, int phy, int regnum)
  59 +{
  60 +       struct qca8k_priv *priv = slave_bus->priv;
  61 +       struct mii_bus *bus = priv->bus;
  62 +
  63 +       return qca8k_mdio_read(bus, phy, regnum);
  64 +}
  65 +
  66 +static int
  67  qca8k_phy_write(struct dsa_switch *ds, int port, int regnum, u16 data)
  68  {
  69         struct qca8k_priv *priv = ds->priv;
  70 @@ -775,8 +789,8 @@ qca8k_mdio_register(struct qca8k_priv *p
  71
  72         bus->priv = (void *)priv;
  73         bus->name = "qca8k slave mii";
  74 -       bus->read = qca8k_mdio_read;
  75 -       bus->write = qca8k_mdio_write;
  76 +       bus->read = qca8k_internal_mdio_read;
  77 +       bus->write = qca8k_internal_mdio_write;
  78         snprintf(bus->id, MII_BUS_ID_SIZE, "qca8k-%d",
  79                  ds->index);
  80