target/linux/generic/backport-5.15/778-v5.18-02-net-phy-at803x-support-downstream-SFP-cage.patch

   1 From dc4d5fcc5d365c9f70ea3f5c09bdf70e988fad50 Mon Sep 17 00:00:00 2001
   2 From: Robert Hancock <robert.hancock@calian.com>
   3 Date: Tue, 25 Jan 2022 10:54:10 -0600
   4 Subject: [PATCH] net: phy: at803x: Support downstream SFP cage
   5
   6 Add support for downstream SFP cages for AR8031 and AR8033. This is
   7 primarily intended for fiber modules or direct-attach cables, however
   8 copper modules which work in 1000Base-X mode may also function. Such
   9 modules are allowed with a warning.
  10
  11 Signed-off-by: Robert Hancock <robert.hancock@calian.com>
  12 Signed-off-by: David S. Miller <davem@davemloft.net>
  13 ---
  14  drivers/net/phy/at803x.c | 56 ++++++++++++++++++++++++++++++++++++++++
  15  1 file changed, 56 insertions(+)
  16
  17 --- a/drivers/net/phy/at803x.c
  18 +++ b/drivers/net/phy/at803x.c
  19 @@ -19,6 +19,8 @@
  20  #include <linux/regulator/of_regulator.h>
  21  #include <linux/regulator/driver.h>
  22  #include <linux/regulator/consumer.h>
  23 +#include <linux/phylink.h>
  24 +#include <linux/sfp.h>
  25  #include <dt-bindings/net/qca-ar803x.h>
  26
  27  #define AT803X_SPECIFIC_FUNCTION_CONTROL       0x10
  28 @@ -555,6 +557,55 @@ static int at8031_register_regulators(st
  29         return 0;
  30  }
  31
  32 +static int at803x_sfp_insert(void *upstream, const struct sfp_eeprom_id *id)
  33 +{
  34 +       struct phy_device *phydev = upstream;
  35 +       __ETHTOOL_DECLARE_LINK_MODE_MASK(phy_support);
  36 +       __ETHTOOL_DECLARE_LINK_MODE_MASK(sfp_support);
  37 +       phy_interface_t iface;
  38 +
  39 +       linkmode_zero(phy_support);
  40 +       phylink_set(phy_support, 1000baseX_Full);
  41 +       phylink_set(phy_support, 1000baseT_Full);
  42 +       phylink_set(phy_support, Autoneg);
  43 +       phylink_set(phy_support, Pause);
  44 +       phylink_set(phy_support, Asym_Pause);
  45 +
  46 +       linkmode_zero(sfp_support);
  47 +       sfp_parse_support(phydev->sfp_bus, id, sfp_support);
  48 +       /* Some modules support 10G modes as well as others we support.
  49 +        * Mask out non-supported modes so the correct interface is picked.
  50 +        */
  51 +       linkmode_and(sfp_support, phy_support, sfp_support);
  52 +
  53 +       if (linkmode_empty(sfp_support)) {
  54 +               dev_err(&phydev->mdio.dev, "incompatible SFP module inserted\n");
  55 +               return -EINVAL;
  56 +       }
  57 +
  58 +       iface = sfp_select_interface(phydev->sfp_bus, sfp_support);
  59 +
  60 +       /* Only 1000Base-X is supported by AR8031/8033 as the downstream SerDes
  61 +        * interface for use with SFP modules.
  62 +        * However, some copper modules detected as having a preferred SGMII
  63 +        * interface do default to and function in 1000Base-X mode, so just
  64 +        * print a warning and allow such modules, as they may have some chance
  65 +        * of working.
  66 +        */
  67 +       if (iface == PHY_INTERFACE_MODE_SGMII)
  68 +               dev_warn(&phydev->mdio.dev, "module may not function if 1000Base-X not supported\n");
  69 +       else if (iface != PHY_INTERFACE_MODE_1000BASEX)
  70 +               return -EINVAL;
  71 +
  72 +       return 0;
  73 +}
  74 +
  75 +static const struct sfp_upstream_ops at803x_sfp_ops = {
  76 +       .attach = phy_sfp_attach,
  77 +       .detach = phy_sfp_detach,
  78 +       .module_insert = at803x_sfp_insert,
  79 +};
  80 +
  81  static int at803x_parse_dt(struct phy_device *phydev)
  82  {
  83         struct device_node *node = phydev->mdio.dev.of_node;
  84 @@ -662,6 +713,11 @@ static int at803x_parse_dt(struct phy_de
  85                         phydev_err(phydev, "failed to get VDDIO regulator\n");
  86                         return PTR_ERR(priv->vddio);
  87                 }
  88 +
  89 +               /* Only AR8031/8033 support 1000Base-X for SFP modules */
  90 +               ret = phy_sfp_probe(phydev, &at803x_sfp_ops);
  91 +               if (ret < 0)
  92 +                       return ret;
  93         }
  94
  95         return 0;