drivers/net/phy: add fixed-phy / fixed-link support

This patch adds support for having a "fixed-link" to some other MAC
(like some embedded switch-device).

For this purpose we introduce a new phy-driver, called "Fixed PHY".

Fixed PHY works only with CONFIG_DM_ETH enabled, since the fixed-link is
described with a subnode below ethernet interface.

Most ethernet drivers (unfortunately not all are following same scheme
for searching/attaching phys) are calling "phy_connect(...)" for getting
a phy-device.
At this point we link in, we search here for a subnode called "fixed-
link", once found we start phy_device_create(...) with the special phy-
id PHY_FIXED_ID (0xa5a55a5a).

During init the "Fixed PHY" driver has registered with this id and now
gets probed, during probe we get all the details about fixed-link out of
dts, later on the phy reports this values.

Signed-off-by: Hannes Schmelzer <hannes.schmelzer@br-automation.com>

Signed-off-by: Hannes Schmelzer <oe5hpm@oevsv.at>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>
Reviewed-by: Christian Gmeiner <christian.gmeiner@gmail.com>

1 files changed, 82 insertions, 0 deletions

diff --git a/drivers/net/phy/fixed.c b/drivers/net/phy/fixed.c
new file mode 100644
index 0000000000..df8235645e
--- /dev/null
+++ b/drivers/net/phy/fixed.c
@@ -0,0 +1,82 @@
+/*
+ * Fixed-Link phy
+ *
+ * Copyright 2017 Bernecker & Rainer Industrieelektronik GmbH
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <config.h>
+#include <common.h>
+#include <phy.h>
+#include <dm.h>
+#include <fdt_support.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+int fixedphy_probe(struct phy_device *phydev)
+{
+	struct fixed_link *priv;
+	int ofnode = phydev->addr;
+	u32 val;
+
+	/* check for mandatory properties within fixed-link node */
+	val = fdt_getprop_u32_default_node(gd->fdt_blob,
+					   ofnode, 0, "speed", 0);
+	if (val != SPEED_10 && val != SPEED_100 && val != SPEED_1000) {
+		printf("ERROR: no/invalid speed given in fixed-link node!");
+		return -EINVAL;
+	}
+
+	priv = malloc(sizeof(*priv));
+	if (!priv)
+		return -ENOMEM;
+	memset(priv, 0, sizeof(*priv));
+
+	phydev->priv = priv;
+	phydev->addr = 0;
+
+	priv->link_speed = val;
+	priv->duplex = fdtdec_get_bool(gd->fdt_blob, ofnode, "full-duplex");
+	priv->pause = fdtdec_get_bool(gd->fdt_blob, ofnode, "pause");
+	priv->asym_pause = fdtdec_get_bool(gd->fdt_blob, ofnode, "asym-pause");
+
+	/* fixed-link phy must not be reset by core phy code */
+	phydev->flags |= PHY_FLAG_BROKEN_RESET;
+
+	return 0;
+}
+
+int fixedphy_startup(struct phy_device *phydev)
+{
+	struct fixed_link *priv = phydev->priv;
+
+	phydev->asym_pause = priv->asym_pause;
+	phydev->pause = priv->pause;
+	phydev->duplex = priv->duplex;
+	phydev->speed = priv->link_speed;
+	phydev->link = 1;
+
+	return 0;
+}
+
+int fixedphy_shutdown(struct phy_device *phydev)
+{
+	return 0;
+}
+
+static struct phy_driver fixedphy_driver = {
+	.uid		= PHY_FIXED_ID,
+	.mask		= 0xffffffff,
+	.name		= "Fixed PHY",
+	.features	= PHY_GBIT_FEATURES | SUPPORTED_MII,
+	.probe		= fixedphy_probe,
+	.startup	= fixedphy_startup,
+	.shutdown	= fixedphy_shutdown,
+};
+
+int phy_fixed_init(void)
+{
+	phy_register(&fixedphy_driver);
+	return 0;
+}