target/linux/generic/backport-5.10/890-v5.19-net-sfp-Add-tx-fault-workaround-for-Huawei-MA5671A-SFP-ON.patch

   1 From f81d97cb646ab8b90fb181d66fccaf9589990de6 Mon Sep 17 00:00:00 2001
   2 From: Matthew Hagan <mnhagan88@gmail.com>
   3 Date: Sat, 30 Apr 2022 11:00:49 +0100
   4 Subject: [PATCH v2] net: sfp: Add tx-fault workaround for Huawei MA5671A SFP
   5  ONT
   6
   7 As noted elsewhere, various GPON SFP modules exhibit non-standard
   8 TX-fault behaviour. In the tested case, the Huawei MA5671A, when used
   9 in combination with a Marvell mv88e6085 switch, was found to
  10 persistently assert TX-fault, resulting in the module being disabled.
  11
  12 This patch adds a quirk to ignore the SFP_F_TX_FAULT state, allowing the
  13 module to function.
  14
  15 Change from v1: removal of erroneous return statment (Andrew Lunn)
  16
  17 Signed-off-by: Matthew Hagan <mnhagan88@gmail.com>
  18 Reviewed-by: Andrew Lunn <andrew@lunn.ch>
  19 ---
  20  drivers/net/phy/sfp.c | 12 +++++++++++-
  21  1 file changed, 11 insertions(+), 1 deletion(-)
  22
  23 --- a/drivers/net/phy/sfp.c
  24 +++ b/drivers/net/phy/sfp.c
  25 @@ -249,6 +249,7 @@ struct sfp {
  26         struct sfp_eeprom_id id;
  27         unsigned int module_power_mW;
  28         unsigned int module_t_start_up;
  29 +       bool tx_fault_ignore;
  30
  31  #if IS_ENABLED(CONFIG_HWMON)
  32         struct sfp_diag diag;
  33 @@ -1893,6 +1894,12 @@ static int sfp_sm_mod_probe(struct sfp *
  34         else
  35                 sfp->module_t_start_up = T_START_UP;
  36
  37 +       if (!memcmp(id.base.vendor_name, "HUAWEI          ", 16) &&
  38 +           !memcmp(id.base.vendor_pn, "MA5671A         ", 16))
  39 +               sfp->tx_fault_ignore = true;
  40 +       else
  41 +               sfp->tx_fault_ignore = false;
  42 +
  43         return 0;
  44  }
  45
  46 @@ -2320,7 +2327,10 @@ static void sfp_check_state(struct sfp *
  47         mutex_lock(&sfp->st_mutex);
  48         state = sfp_get_state(sfp);
  49         changed = state ^ sfp->state;
  50 -       changed &= SFP_F_PRESENT | SFP_F_LOS | SFP_F_TX_FAULT;
  51 +       if (sfp->tx_fault_ignore)
  52 +               changed &= SFP_F_PRESENT | SFP_F_LOS;
  53 +       else
  54 +               changed &= SFP_F_PRESENT | SFP_F_LOS | SFP_F_TX_FAULT;
  55
  56         for (i = 0; i < GPIO_MAX; i++)
  57                 if (changed & BIT(i))