target/linux/generic/pending-4.4/737-net-phy-at803x-Request-reset-GPIO-only-for-AT8030-PH.patch

   1 From: Sebastian Frias <sf84@laposte.net>
   2 Date: Wed, 23 Mar 2016 11:49:09 +0100
   3 Subject: [PATCH] net: phy: at803x: Request 'reset' GPIO only for AT8030 PHY
   4
   5 This removes the dependency on GPIOLIB for non faulty PHYs.
   6
   7 Indeed, without this patch, if GPIOLIB is not selected
   8 devm_gpiod_get_optional() will return -ENOSYS and the driver probe
   9 call will fail, regardless of the actual PHY hardware.
  10
  11 Out of the 3 PHYs supported by this driver (AT8030, AT8031, AT8035),
  12 only AT8030 presents the issues that commit 13a56b449325 ("net: phy:
  13 at803x: Add support for hardware reset") attempts to work-around by
  14 using a 'reset' GPIO line.
  15
  16 Hence, only AT8030 should depend on GPIOLIB operating properly.
  17
  18 Fixes: 13a56b449325 ("net: phy: at803x: Add support for hardware reset")
  19
  20 Signed-off-by: Sebastian Frias <sf84@laposte.net>
  21 Signed-off-by: David S. Miller <davem@davemloft.net>
  22 ---
  23
  24 --- a/drivers/net/phy/at803x.c
  25 +++ b/drivers/net/phy/at803x.c
  26 @@ -250,12 +250,16 @@ static int at803x_probe(struct phy_devic
  27         if (!priv)
  28                 return -ENOMEM;
  29
  30 +       if (phydev->drv->phy_id != ATH8030_PHY_ID)
  31 +               goto does_not_require_reset_workaround;
  32 +
  33         gpiod_reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
  34         if (IS_ERR(gpiod_reset))
  35                 return PTR_ERR(gpiod_reset);
  36
  37         priv->gpiod_reset = gpiod_reset;
  38
  39 +does_not_require_reset_workaround:
  40         phydev->priv = priv;
  41
  42         return 0;