target/linux/generic/backport-5.15/769-v5.19-03-net-dsa-qca8k-rework-and-simplify-mdiobus-logic.patch

   1 From 8255212e4130bd2dc1463286a3dddb74797bbdc1 Mon Sep 17 00:00:00 2001
   2 From: Ansuel Smith <ansuelsmth@gmail.com>
   3 Date: Sat, 16 Apr 2022 01:30:14 +0200
   4 Subject: [PATCH 3/6] net: dsa: qca8k: rework and simplify mdiobus logic
   5
   6 In an attempt to reduce qca8k_priv space, rework and simplify mdiobus
   7 logic.
   8 We now declare a mdiobus instead of relying on DSA phy_read/write even
   9 if a mdio node is not present. This is all to make the qca8k ops static
  10 and not switch specific. With a legacy implementation where port doesn't
  11 have a phy map declared in the dts with a mdio node, we declare a
  12 'qca8k-legacy' mdiobus. The conversion logic is used as legacy read and
  13 write ops are used instead of the internal one.
  14 Also drop the legacy_phy_port_mapping as we now declare mdiobus with ops
  15 that already address the workaround.
  16
  17 Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
  18 Signed-off-by: David S. Miller <davem@davemloft.net>
  19 ---
  20  drivers/net/dsa/qca8k.c | 95 +++++++++++++----------------------------
  21  drivers/net/dsa/qca8k.h |  1 -
  22  2 files changed, 29 insertions(+), 67 deletions(-)
  23
  24 --- a/drivers/net/dsa/qca8k.c
  25 +++ b/drivers/net/dsa/qca8k.c
  26 @@ -1291,83 +1291,63 @@ qca8k_internal_mdio_read(struct mii_bus
  27  }
  28
  29  static int
  30 -qca8k_phy_write(struct dsa_switch *ds, int port, int regnum, u16 data)
  31 +qca8k_legacy_mdio_write(struct mii_bus *slave_bus, int port, int regnum, u16 data)
  32  {
  33 -       struct qca8k_priv *priv = ds->priv;
  34 -       int ret;
  35 +       port = qca8k_port_to_phy(port) % PHY_MAX_ADDR;
  36
  37 -       /* Check if the legacy mapping should be used and the
  38 -        * port is not correctly mapped to the right PHY in the
  39 -        * devicetree
  40 -        */
  41 -       if (priv->legacy_phy_port_mapping)
  42 -               port = qca8k_port_to_phy(port) % PHY_MAX_ADDR;
  43 -
  44 -       /* Use mdio Ethernet when available, fallback to legacy one on error */
  45 -       ret = qca8k_phy_eth_command(priv, false, port, regnum, 0);
  46 -       if (!ret)
  47 -               return ret;
  48 -
  49 -       return qca8k_mdio_write(priv, port, regnum, data);
  50 +       return qca8k_internal_mdio_write(slave_bus, port, regnum, data);
  51  }
  52
  53  static int
  54 -qca8k_phy_read(struct dsa_switch *ds, int port, int regnum)
  55 +qca8k_legacy_mdio_read(struct mii_bus *slave_bus, int port, int regnum)
  56  {
  57 -       struct qca8k_priv *priv = ds->priv;
  58 -       int ret;
  59 -
  60 -       /* Check if the legacy mapping should be used and the
  61 -        * port is not correctly mapped to the right PHY in the
  62 -        * devicetree
  63 -        */
  64 -       if (priv->legacy_phy_port_mapping)
  65 -               port = qca8k_port_to_phy(port) % PHY_MAX_ADDR;
  66 -
  67 -       /* Use mdio Ethernet when available, fallback to legacy one on error */
  68 -       ret = qca8k_phy_eth_command(priv, true, port, regnum, 0);
  69 -       if (ret >= 0)
  70 -               return ret;
  71 -
  72 -       ret = qca8k_mdio_read(priv, port, regnum);
  73 -
  74 -       if (ret < 0)
  75 -               return 0xffff;
  76 +       port = qca8k_port_to_phy(port) % PHY_MAX_ADDR;
  77
  78 -       return ret;
  79 +       return qca8k_internal_mdio_read(slave_bus, port, regnum);
  80  }
  81
  82  static int
  83 -qca8k_mdio_register(struct qca8k_priv *priv, struct device_node *mdio)
  84 +qca8k_mdio_register(struct qca8k_priv *priv)
  85  {
  86         struct dsa_switch *ds = priv->ds;
  87 +       struct device_node *mdio;
  88         struct mii_bus *bus;
  89
  90         bus = devm_mdiobus_alloc(ds->dev);
  91 -
  92         if (!bus)
  93                 return -ENOMEM;
  94
  95         bus->priv = (void *)priv;
  96 -       bus->name = "qca8k slave mii";
  97 -       bus->read = qca8k_internal_mdio_read;
  98 -       bus->write = qca8k_internal_mdio_write;
  99 -       snprintf(bus->id, MII_BUS_ID_SIZE, "qca8k-%d",
 100 -                ds->index);
 101 -
 102         bus->parent = ds->dev;
 103         bus->phy_mask = ~ds->phys_mii_mask;
 104 -
 105         ds->slave_mii_bus = bus;
 106
 107 -       return devm_of_mdiobus_register(priv->dev, bus, mdio);
 108 +       /* Check if the devicetree declare the port:phy mapping */
 109 +       mdio = of_get_child_by_name(priv->dev->of_node, "mdio");
 110 +       if (of_device_is_available(mdio)) {
 111 +               snprintf(bus->id, MII_BUS_ID_SIZE, "qca8k-%d", ds->index);
 112 +               bus->name = "qca8k slave mii";
 113 +               bus->read = qca8k_internal_mdio_read;
 114 +               bus->write = qca8k_internal_mdio_write;
 115 +               return devm_of_mdiobus_register(priv->dev, bus, mdio);
 116 +       }
 117 +
 118 +       /* If a mapping can't be found the legacy mapping is used,
 119 +        * using the qca8k_port_to_phy function
 120 +        */
 121 +       snprintf(bus->id, MII_BUS_ID_SIZE, "qca8k-%d.%d",
 122 +                ds->dst->index, ds->index);
 123 +       bus->name = "qca8k-legacy slave mii";
 124 +       bus->read = qca8k_legacy_mdio_read;
 125 +       bus->write = qca8k_legacy_mdio_write;
 126 +       return devm_mdiobus_register(priv->dev, bus);
 127  }
 128
 129  static int
 130  qca8k_setup_mdio_bus(struct qca8k_priv *priv)
 131  {
 132         u32 internal_mdio_mask = 0, external_mdio_mask = 0, reg;
 133 -       struct device_node *ports, *port, *mdio;
 134 +       struct device_node *ports, *port;
 135         phy_interface_t mode;
 136         int err;
 137
 138 @@ -1429,24 +1409,7 @@ qca8k_setup_mdio_bus(struct qca8k_priv *
 139                                          QCA8K_MDIO_MASTER_EN);
 140         }
 141
 142 -       /* Check if the devicetree declare the port:phy mapping */
 143 -       mdio = of_get_child_by_name(priv->dev->of_node, "mdio");
 144 -       if (of_device_is_available(mdio)) {
 145 -               err = qca8k_mdio_register(priv, mdio);
 146 -               if (err)
 147 -                       of_node_put(mdio);
 148 -
 149 -               return err;
 150 -       }
 151 -
 152 -       /* If a mapping can't be found the legacy mapping is used,
 153 -        * using the qca8k_port_to_phy function
 154 -        */
 155 -       priv->legacy_phy_port_mapping = true;
 156 -       priv->ops.phy_read = qca8k_phy_read;
 157 -       priv->ops.phy_write = qca8k_phy_write;
 158 -
 159 -       return 0;
 160 +       return qca8k_mdio_register(priv);
 161  }
 162
 163  static int
 164 --- a/drivers/net/dsa/qca8k.h
 165 +++ b/drivers/net/dsa/qca8k.h
 166 @@ -382,7 +382,6 @@ struct qca8k_priv {
 167          * Bit 1: port enabled. Bit 0: port disabled.
 168          */
 169         u8 port_enabled_map;
 170 -       bool legacy_phy_port_mapping;
 171         struct qca8k_ports_config ports_config;
 172         struct regmap *regmap;
 173         struct mii_bus *bus;