target/linux/mvebu/patches-3.14/020-of_fixed_link_phy.patch

   1 From 3be2a49e5c08d268f8af0dd4fe89a24ea8cdc339 Mon Sep 17 00:00:00 2001
   2 From: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
   3 Date: Fri, 16 May 2014 16:14:05 +0200
   4 Subject: of: provide a binding for fixed link PHYs
   5
   6 Some Ethernet MACs have a "fixed link", and are not connected to a
   7 normal MDIO-managed PHY device. For those situations, a Device Tree
   8 binding allows to describe a "fixed link" using a special PHY node.
   9
  10 This patch adds:
  11
  12  * A documentation for the fixed PHY Device Tree binding.
  13
  14  * An of_phy_is_fixed_link() function that an Ethernet driver can call
  15    on its PHY phandle to find out whether it's a fixed link PHY or
  16    not. It should typically be used to know if
  17    of_phy_register_fixed_link() should be called.
  18
  19  * An of_phy_register_fixed_link() function that instantiates the
  20    fixed PHY into the PHY subsystem, so that when the driver calls
  21    of_phy_connect(), the PHY device associated to the OF node will be
  22    found.
  23
  24 These two additional functions also support the old fixed-link Device
  25 Tree binding used on PowerPC platforms, so that ultimately, the
  26 network device drivers for those platforms could be converted to use
  27 of_phy_is_fixed_link() and of_phy_register_fixed_link() instead of
  28 of_phy_connect_fixed_link(), while keeping compatibility with their
  29 respective Device Tree bindings.
  30
  31 Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
  32 Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
  33 Tested-by: Florian Fainelli <f.fainelli@gmail.com>
  34 Signed-off-by: David S. Miller <davem@davemloft.net>
  35
  36 --- /dev/null
  37 +++ b/Documentation/devicetree/bindings/net/fixed-link.txt
  38 @@ -0,0 +1,30 @@
  39 +Fixed link Device Tree binding
  40 +------------------------------
  41 +
  42 +Some Ethernet MACs have a "fixed link", and are not connected to a
  43 +normal MDIO-managed PHY device. For those situations, a Device Tree
  44 +binding allows to describe a "fixed link".
  45 +
  46 +Such a fixed link situation is described by creating a 'fixed-link'
  47 +sub-node of the Ethernet MAC device node, with the following
  48 +properties:
  49 +
  50 +* 'speed' (integer, mandatory), to indicate the link speed. Accepted
  51 +  values are 10, 100 and 1000
  52 +* 'full-duplex' (boolean, optional), to indicate that full duplex is
  53 +  used. When absent, half duplex is assumed.
  54 +* 'pause' (boolean, optional), to indicate that pause should be
  55 +  enabled.
  56 +* 'asym-pause' (boolean, optional), to indicate that asym_pause should
  57 +  be enabled.
  58 +
  59 +Example:
  60 +
  61 +ethernet@0 {
  62 +       ...
  63 +       fixed-link {
  64 +             speed = <1000>;
  65 +             full-duplex;
  66 +       };
  67 +       ...
  68 +};
  69 --- a/drivers/of/of_mdio.c
  70 +++ b/drivers/of/of_mdio.c
  71 @@ -14,6 +14,7 @@
  72  #include <linux/netdevice.h>
  73  #include <linux/err.h>
  74  #include <linux/phy.h>
  75 +#include <linux/phy_fixed.h>
  76  #include <linux/of.h>
  77  #include <linux/of_irq.h>
  78  #include <linux/of_mdio.h>
  79 @@ -280,3 +281,69 @@ struct phy_device *of_phy_attach(struct
  80         return phy_attach_direct(dev, phy, flags, iface) ? NULL : phy;
  81  }
  82  EXPORT_SYMBOL(of_phy_attach);
  83 +
  84 +#if defined(CONFIG_FIXED_PHY)
  85 +/*
  86 + * of_phy_is_fixed_link() and of_phy_register_fixed_link() must
  87 + * support two DT bindings:
  88 + * - the old DT binding, where 'fixed-link' was a property with 5
  89 + *   cells encoding various informations about the fixed PHY
  90 + * - the new DT binding, where 'fixed-link' is a sub-node of the
  91 + *   Ethernet device.
  92 + */
  93 +bool of_phy_is_fixed_link(struct device_node *np)
  94 +{
  95 +       struct device_node *dn;
  96 +       int len;
  97 +
  98 +       /* New binding */
  99 +       dn = of_get_child_by_name(np, "fixed-link");
 100 +       if (dn) {
 101 +               of_node_put(dn);
 102 +               return true;
 103 +       }
 104 +
 105 +       /* Old binding */
 106 +       if (of_get_property(np, "fixed-link", &len) &&
 107 +           len == (5 * sizeof(__be32)))
 108 +               return true;
 109 +
 110 +       return false;
 111 +}
 112 +EXPORT_SYMBOL(of_phy_is_fixed_link);
 113 +
 114 +int of_phy_register_fixed_link(struct device_node *np)
 115 +{
 116 +       struct fixed_phy_status status = {};
 117 +       struct device_node *fixed_link_node;
 118 +       const __be32 *fixed_link_prop;
 119 +       int len;
 120 +
 121 +       /* New binding */
 122 +       fixed_link_node = of_get_child_by_name(np, "fixed-link");
 123 +       if (fixed_link_node) {
 124 +               status.link = 1;
 125 +               status.duplex = of_property_read_bool(np, "full-duplex");
 126 +               if (of_property_read_u32(fixed_link_node, "speed", &status.speed))
 127 +                       return -EINVAL;
 128 +               status.pause = of_property_read_bool(np, "pause");
 129 +               status.asym_pause = of_property_read_bool(np, "asym-pause");
 130 +               of_node_put(fixed_link_node);
 131 +               return fixed_phy_register(PHY_POLL, &status, np);
 132 +       }
 133 +
 134 +       /* Old binding */
 135 +       fixed_link_prop = of_get_property(np, "fixed-link", &len);
 136 +       if (fixed_link_prop && len == (5 * sizeof(__be32))) {
 137 +               status.link = 1;
 138 +               status.duplex = be32_to_cpu(fixed_link_prop[1]);
 139 +               status.speed = be32_to_cpu(fixed_link_prop[2]);
 140 +               status.pause = be32_to_cpu(fixed_link_prop[3]);
 141 +               status.asym_pause = be32_to_cpu(fixed_link_prop[4]);
 142 +               return fixed_phy_register(PHY_POLL, &status, np);
 143 +       }
 144 +
 145 +       return -ENODEV;
 146 +}
 147 +EXPORT_SYMBOL(of_phy_register_fixed_link);
 148 +#endif
 149 --- a/include/linux/of_mdio.h
 150 +++ b/include/linux/of_mdio.h
 151 @@ -67,4 +67,19 @@ static inline struct mii_bus *of_mdio_fi
 152  }
 153  #endif /* CONFIG_OF */
 154
 155 +#if defined(CONFIG_OF) && defined(CONFIG_FIXED_PHY)
 156 +extern int of_phy_register_fixed_link(struct device_node *np);
 157 +extern bool of_phy_is_fixed_link(struct device_node *np);
 158 +#else
 159 +static inline int of_phy_register_fixed_link(struct device_node *np)
 160 +{
 161 +       return -ENOSYS;
 162 +}
 163 +static inline bool of_phy_is_fixed_link(struct device_node *np)
 164 +{
 165 +       return false;
 166 +}
 167 +#endif
 168 +
 169 +
 170  #endif /* __LINUX_OF_MDIO_H */