Provide a named definition for the power level select bit in the
extended status register, rather than using BIT(0) in the code.
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
         * all bytes 0xff) at 0x51 but does not accept writes.  In any case,
         * if the bit is already set, we're already in high power mode.
         */
-       if (!!(val & BIT(0)) == enable)
+       if (!!(val & SFP_EXT_STATUS_PWRLVL_SELECT) == enable)
                return 0;
 
        if (enable)
-               val |= BIT(0);
+               val |= SFP_EXT_STATUS_PWRLVL_SELECT;
        else
-               val &= ~BIT(0);
+               val &= ~SFP_EXT_STATUS_PWRLVL_SELECT;
 
        err = sfp_write(sfp, true, SFP_EXT_STATUS, &val, sizeof(val));
        if (err != sizeof(val)) {
 
        SFP_WARN1_RXPWR_LOW             = BIT(6),
 
        SFP_EXT_STATUS                  = 0x76,
+       SFP_EXT_STATUS_PWRLVL_SELECT    = BIT(0),
+
        SFP_VSL                         = 0x78,
        SFP_PAGE                        = 0x7f,
 };