[RFC PATCH 2/3] net/dsa: Allow probing dsa from usbnet

[Jan Kaisrlik <kaisrja1@fel.cvut.cz>]

From: Jan Kaisrlik <ja.kaisrlik@gmail.com>

This patch adds a function which helps to connect net device
to DSA switch based on mii_bus and netdev.

The switch parameters of the switch are configured in fill_platform_data().
Currently, the configuration data is hardcoded in the code.
I don't know how to pass the configuration data from
user space.

It is not possible to determine the configuration data in plug-and-play
manner in mv88e6060 driver.

I have thought about two possibilities how to do that. First one is to
load data from the device tree, because loading from device tree is
already implemented in dsa_of_probe().

Second possibility is to send configuration of switch via sysfs.

In my opinion, the second one is better because I have already used
sysfs to bind USB to DSA in patch 3/3.

---
 include/net/dsa.h |   3 ++
 net/dsa/dsa.c     | 121 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 124 insertions(+)

diff --git a/include/net/dsa.h b/include/net/dsa.h
index ed3c34b..df7b748 100644
--- a/include/net/dsa.h
+++ b/include/net/dsa.h
@@ -290,4 +290,7 @@ static inline bool dsa_uses_tagged_protocol(struct dsa_switch_tree *dst)
 {
 	return dst->rcv != NULL;
 }
+
+int dsa_probe_mii(struct mii_bus *bus, struct net_device * dev);
+
 #endif
diff --git a/net/dsa/dsa.c b/net/dsa/dsa.c
index e2c0703..cb5d9c2 100644
--- a/net/dsa/dsa.c
+++ b/net/dsa/dsa.c
@@ -798,6 +798,127 @@ out:
 	return ret;
 }
 
+static int fill_platform_data(struct dsa_platform_data *pd,
+		struct mii_bus *bus, struct device * parent){
+	struct dsa_chip_data * cd;
+	int i;
+
+	static struct device_node dn = {
+		.name = "name",
+		.type = "type",
+		.phandle = 0,
+		.full_name = "fullname",
+		.fwnode =  {1},
+		.properties = NULL,
+		.deadprops = NULL,
+		.parent = NULL,
+		.child = NULL,
+		.sibling = NULL,
+		.kobj = {NULL},
+		._flags = 0,
+		.data = NULL
+	};
+	static struct device_node dnc = {
+		.name = "name",
+		.type = "type",
+		.phandle = 0,
+		.full_name = "fullname",
+		.fwnode =  {1},
+		.properties = NULL,
+		.deadprops = NULL,
+		.parent = &dn,
+		.child = NULL,
+		.sibling = NULL,
+		.kobj = {NULL},
+		._flags = 0,
+		.data = NULL
+	};
+	static char *port_names[12] = {"0", "1", "2", "3", "4",
+		"5", "6", "7", "8", "9", "10", "11"};
+
+	pd->nr_chips = 1;
+	pd->netdev = parent;
+
+	cd = kzalloc(sizeof(*cd), GFP_KERNEL);
+	if (cd == NULL)
+		return -ENOMEM;
+
+	pd->chip = cd;
+
+	cd->host_dev = parent;
+	cd->sw_addr = 0x10;
+	cd->eeprom_len = 256;
+	cd->of_node = &dn;
+	cd->rtable = 0;
+
+//	cd->of_node = kzalloc(sizeof(*cd->of_node), GFP_KERNEL);
+//	if(cd->of_node == NULL)
+//		goto free;
+
+	for (i = 0; i < DSA_MAX_PORTS; i++) {
+		cd->port_names[i] = port_names[i];
+		cd->port_dn[i] = &dnc;
+	}
+
+	return 0;
+
+//free:
+//	kfree(cd);
+//	return -ENOMEM;
+}
+
+int dsa_probe_mii(struct mii_bus *bus, struct net_device * dev)
+{
+	struct dsa_platform_data *pd;
+	struct dsa_switch_tree *dst;
+	int ret;
+
+	pr_notice_once("Distributed Switch Architecture driver version %s\n",
+		       dsa_driver_version);
+
+	if (dev == NULL || bus == NULL)
+		return -EINVAL;
+
+	pd = kzalloc(sizeof(*pd), GFP_KERNEL);
+	if (pd == NULL) {
+		ret = -ENOMEM;
+		goto freep;
+	}
+
+	ret = fill_platform_data(pd, bus, bus->parent); //TODO fix it!
+	if (ret)
+		goto freep;
+
+	if (dev->dsa_ptr != NULL) {
+		dev_put(dev);
+		ret = -EEXIST;
+		goto freep;
+	}
+
+	dst = kzalloc(sizeof(*dst), GFP_KERNEL);
+	if (dst == NULL) {
+		dev_put(dev);
+		ret = -ENOMEM;
+		goto freed;
+	}
+
+	dev_set_drvdata(bus->parent, dst);
+
+	dst->pd = pd;
+	dst->master_netdev = dev;
+
+	dsa_probe_common(dst, bus->parent);
+
+	return 0;
+
+freed:
+	kfree(dst);
+freep:
+	kfree(pd);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(dsa_probe_mii);
+
 static int dsa_remove(struct platform_device *pdev)
 {
 	struct dsa_switch_tree *dst = platform_get_drvdata(pdev);
-- 
2.1.3