Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / drivers / net / ethernet / arc / emac_mdio.c

diff --git a/kernel/drivers/net/ethernet/arc/emac_mdio.c b/kernel/drivers/net/ethernet/arc/emac_mdio.c
new file mode 100644 (file)
index 0000000..d5ee986
--- /dev/null
+++ b/kernel/drivers/net/ethernet/arc/emac_mdio.c
@@ -0,0 +1,151 @@
+/*
+ * Copyright (C) 2004-2013 Synopsys, Inc. (www.synopsys.com)
+ *
+ * MDIO implementation for ARC EMAC
+ */
+
+#include <linux/delay.h>
+#include <linux/of_mdio.h>
+#include <linux/platform_device.h>
+
+#include "emac.h"
+
+/* Number of seconds we wait for "MDIO complete" flag to appear */
+#define ARC_MDIO_COMPLETE_POLL_COUNT   1
+
+/**
+ * arc_mdio_complete_wait - Waits until MDIO transaction is completed.
+ * @priv:      Pointer to ARC EMAC private data structure.
+ *
+ * returns:    0 on success, -ETIMEDOUT on a timeout.
+ */
+static int arc_mdio_complete_wait(struct arc_emac_priv *priv)
+{
+       unsigned int i;
+
+       for (i = 0; i < ARC_MDIO_COMPLETE_POLL_COUNT * 40; i++) {
+               unsigned int status = arc_reg_get(priv, R_STATUS);
+
+               status &= MDIO_MASK;
+
+               if (status) {
+                       /* Reset "MDIO complete" flag */
+                       arc_reg_set(priv, R_STATUS, status);
+                       return 0;
+               }
+
+               msleep(25);
+       }
+
+       return -ETIMEDOUT;
+}
+
+/**
+ * arc_mdio_read - MDIO interface read function.
+ * @bus:       Pointer to MII bus structure.
+ * @phy_addr:  Address of the PHY device.
+ * @reg_num:   PHY register to read.
+ *
+ * returns:    The register contents on success, -ETIMEDOUT on a timeout.
+ *
+ * Reads the contents of the requested register from the requested PHY
+ * address.
+ */
+static int arc_mdio_read(struct mii_bus *bus, int phy_addr, int reg_num)
+{
+       struct arc_emac_priv *priv = bus->priv;
+       unsigned int value;
+       int error;
+
+       arc_reg_set(priv, R_MDIO,
+                   0x60020000 | (phy_addr << 23) | (reg_num << 18));
+
+       error = arc_mdio_complete_wait(priv);
+       if (error < 0)
+               return error;
+
+       value = arc_reg_get(priv, R_MDIO) & 0xffff;
+
+       dev_dbg(priv->dev, "arc_mdio_read(phy_addr=%i, reg_num=%x) = %x\n",
+               phy_addr, reg_num, value);
+
+       return value;
+}
+
+/**
+ * arc_mdio_write - MDIO interface write function.
+ * @bus:       Pointer to MII bus structure.
+ * @phy_addr:  Address of the PHY device.
+ * @reg_num:   PHY register to write to.
+ * @value:     Value to be written into the register.
+ *
+ * returns:    0 on success, -ETIMEDOUT on a timeout.
+ *
+ * Writes the value to the requested register.
+ */
+static int arc_mdio_write(struct mii_bus *bus, int phy_addr,
+                         int reg_num, u16 value)
+{
+       struct arc_emac_priv *priv = bus->priv;
+
+       dev_dbg(priv->dev,
+               "arc_mdio_write(phy_addr=%i, reg_num=%x, value=%x)\n",
+               phy_addr, reg_num, value);
+
+       arc_reg_set(priv, R_MDIO,
+                    0x50020000 | (phy_addr << 23) | (reg_num << 18) | value);
+
+       return arc_mdio_complete_wait(priv);
+}
+
+/**
+ * arc_mdio_probe - MDIO probe function.
+ * @priv:      Pointer to ARC EMAC private data structure.
+ *
+ * returns:    0 on success, -ENOMEM when mdiobus_alloc
+ * (to allocate memory for MII bus structure) fails.
+ *
+ * Sets up and registers the MDIO interface.
+ */
+int arc_mdio_probe(struct arc_emac_priv *priv)
+{
+       struct mii_bus *bus;
+       int error;
+
+       bus = mdiobus_alloc();
+       if (!bus)
+               return -ENOMEM;
+
+       priv->bus = bus;
+       bus->priv = priv;
+       bus->parent = priv->dev;
+       bus->name = "Synopsys MII Bus",
+       bus->read = &arc_mdio_read;
+       bus->write = &arc_mdio_write;
+
+       snprintf(bus->id, MII_BUS_ID_SIZE, "%s", bus->name);
+
+       error = of_mdiobus_register(bus, priv->dev->of_node);
+       if (error) {
+               dev_err(priv->dev, "cannot register MDIO bus %s\n", bus->name);
+               mdiobus_free(bus);
+               return error;
+       }
+
+       return 0;
+}
+
+/**
+ * arc_mdio_remove - MDIO remove function.
+ * @priv:      Pointer to ARC EMAC private data structure.
+ *
+ * Unregisters the MDIO and frees any associate memory for MII bus.
+ */
+int arc_mdio_remove(struct arc_emac_priv *priv)
+{
+       mdiobus_unregister(priv->bus);
+       mdiobus_free(priv->bus);
+       priv->bus = NULL;
+
+       return 0;
+}