• Sergei Shtylyov's avatar
    phylib: Add device reset GPIO support · bafbdd52
    Sergei Shtylyov authored
    The PHY devices sometimes do have their reset signal (maybe even power
    supply?) tied to some GPIO and sometimes it also does happen that a boot
    loader does not leave it deasserted. So far this issue has been attacked
    from (as I believe) a wrong angle: by teaching the MAC driver to manipulate
    the GPIO in question; that solution, when applied to the device trees, led
    to adding the PHY reset GPIO properties to the MAC device node, with one
    exception: Cadence MACB driver which could handle the "reset-gpios" prop
    in a PHY device subnode. I believe that the correct approach is to teach
    the 'phylib' to get the MDIO device reset GPIO from the device tree node
    corresponding to this device -- which this patch is doing...
    
    Note that I had to modify the AT803x PHY driver as it would stop working
    otherwise -- it made use of the reset GPIO for its own purposes...
    Signed-off-by: default avatarSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
    Acked-by: default avatarRob Herring <robh@kernel.org>
    [geert: Propagate actual errors from fwnode_get_named_gpiod()]
    [geert: Avoid destroying initial setup]
    [geert: Consolidate GPIO descriptor acquiring code]
    Signed-off-by: default avatarGeert Uytterhoeven <geert+renesas@glider.be>
    Tested-by: default avatarRichard Leitner <richard.leitner@skidata.com>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    bafbdd52
phy_device.c 48.7 KB