[PATCH net-next v5 2/4] net: dsa: Add support for platform data

From: Florian Fainelli
Date: Sat Feb 04 2017 - 16:03:06 EST


Allow drivers to use the new DSA API with platform data. Most of the
code in net/dsa/dsa2.c does not rely so much on device_nodes and can get
the same information from platform_data instead.

We purposely do not support distributed configurations with platform
data, so drivers should be providing a pointer to a 'struct
dsa_chip_data' structure if they wish to communicate per-port layout.

Multiple CPUs port could potentially be supported and dsa_chip_data is
extended to receive up to one reference to an upstream network device
per port described by a dsa_chip_data structure.

dsa_dev_to_net_device() increments the network device's reference count,
so we intentionally call dev_put() to be consistent with the DT-enabled
path, until we have a generic notifier based solution.

Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
---
include/net/dsa.h | 6 ++++
net/dsa/dsa2.c | 102 ++++++++++++++++++++++++++++++++++++++++++++----------
2 files changed, 90 insertions(+), 18 deletions(-)

diff --git a/include/net/dsa.h b/include/net/dsa.h
index 4327b0b03293..4449f22c64ba 100644
--- a/include/net/dsa.h
+++ b/include/net/dsa.h
@@ -44,6 +44,11 @@ struct dsa_chip_data {
struct device *host_dev;
int sw_addr;

+ /*
+ * Reference to network devices
+ */
+ struct device *netdev[DSA_MAX_PORTS];
+
/* set to size of eeprom if supported by the switch */
int eeprom_len;

@@ -166,6 +171,7 @@ struct dsa_mall_tc_entry {
struct dsa_port {
struct dsa_switch *ds;
unsigned int index;
+ const char *name;
struct net_device *netdev;
struct device_node *dn;
unsigned int ageing_time;
diff --git a/net/dsa/dsa2.c b/net/dsa/dsa2.c
index 9f8cc26be9ea..3a7631f63638 100644
--- a/net/dsa/dsa2.c
+++ b/net/dsa/dsa2.c
@@ -78,19 +78,28 @@ static void dsa_dst_del_ds(struct dsa_switch_tree *dst,
kref_put(&dst->refcount, dsa_free_dst);
}

+/* For platform data configurations, we need to have a valid name argument to
+ * differentiate a disabled port from an enabled one
+ */
static bool dsa_port_is_valid(struct dsa_port *port)
{
- return !!port->dn;
+ return !!(port->dn || port->name);
}

static bool dsa_port_is_dsa(struct dsa_port *port)
{
- return !!of_parse_phandle(port->dn, "link", 0);
+ if (port->name && !strcmp(port->name, "dsa"))
+ return true;
+ else
+ return !!of_parse_phandle(port->dn, "link", 0);
}

static bool dsa_port_is_cpu(struct dsa_port *port)
{
- return !!of_parse_phandle(port->dn, "ethernet", 0);
+ if (port->name && !strcmp(port->name, "cpu"))
+ return true;
+ else
+ return !!of_parse_phandle(port->dn, "ethernet", 0);
}

static bool dsa_ds_find_port_dn(struct dsa_switch *ds,
@@ -250,10 +259,11 @@ static void dsa_cpu_port_unapply(struct dsa_port *port, u32 index,
static int dsa_user_port_apply(struct dsa_port *port, u32 index,
struct dsa_switch *ds)
{
- const char *name;
+ const char *name = port->name;
int err;

- name = of_get_property(port->dn, "label", NULL);
+ if (port->dn)
+ name = of_get_property(port->dn, "label", NULL);
if (!name)
name = "eth%d";

@@ -438,11 +448,16 @@ static int dsa_cpu_parse(struct dsa_port *port, u32 index,
struct net_device *ethernet_dev;
struct device_node *ethernet;

- ethernet = of_parse_phandle(port->dn, "ethernet", 0);
- if (!ethernet)
- return -EINVAL;
+ if (port->dn) {
+ ethernet = of_parse_phandle(port->dn, "ethernet", 0);
+ if (!ethernet)
+ return -EINVAL;
+ ethernet_dev = of_find_net_device_by_node(ethernet);
+ } else {
+ ethernet_dev = dsa_dev_to_net_device(ds->cd->netdev[index]);
+ dev_put(ethernet_dev);
+ }

- ethernet_dev = of_find_net_device_by_node(ethernet);
if (!ethernet_dev)
return -EPROBE_DEFER;

@@ -545,6 +560,33 @@ static int dsa_parse_ports_dn(struct device_node *ports, struct dsa_switch *ds)
return 0;
}

+static int dsa_parse_ports(struct dsa_chip_data *cd, struct dsa_switch *ds)
+{
+ bool valid_name_found = false;
+ unsigned int i;
+
+ for (i = 0; i < DSA_MAX_PORTS; i++) {
+ if (!cd->port_names[i])
+ continue;
+
+ ds->ports[i].name = cd->port_names[i];
+
+ /* Initialize enabled_port_mask now for drv->setup()
+ * to have access to a correct value, just like what
+ * net/dsa/dsa.c::dsa_switch_setup_one does.
+ */
+ if (!dsa_port_is_cpu(&ds->ports[i]))
+ ds->enabled_port_mask |= 1 << i;
+
+ valid_name_found = true;
+ }
+
+ if (!valid_name_found && i == DSA_MAX_PORTS)
+ return -EINVAL;
+
+ return 0;
+}
+
static int dsa_parse_member_dn(struct device_node *np, u32 *tree, u32 *index)
{
int err;
@@ -569,6 +611,18 @@ static int dsa_parse_member_dn(struct device_node *np, u32 *tree, u32 *index)
return 0;
}

+static int dsa_parse_member(struct dsa_chip_data *pd, u32 *tree, u32 *index)
+{
+ if (!pd)
+ return -ENODEV;
+
+ /* We do not support complex trees with dsa_chip_data */
+ *tree = 0;
+ *index = 0;
+
+ return 0;
+}
+
static struct device_node *dsa_get_ports(struct dsa_switch *ds,
struct device_node *np)
{
@@ -585,23 +639,34 @@ static struct device_node *dsa_get_ports(struct dsa_switch *ds,

static int _dsa_register_switch(struct dsa_switch *ds, struct device *dev)
{
+ struct dsa_chip_data *pdata = dev->platform_data;
struct device_node *np = dev->of_node;
struct dsa_switch_tree *dst;
struct device_node *ports;
u32 tree, index;
int i, err;

- err = dsa_parse_member_dn(np, &tree, &index);
- if (err)
- return err;
+ if (np) {
+ err = dsa_parse_member_dn(np, &tree, &index);
+ if (err)
+ return err;

- ports = dsa_get_ports(ds, np);
- if (IS_ERR(ports))
- return PTR_ERR(ports);
+ ports = dsa_get_ports(ds, np);
+ if (IS_ERR(ports))
+ return PTR_ERR(ports);

- err = dsa_parse_ports_dn(ports, ds);
- if (err)
- return err;
+ err = dsa_parse_ports_dn(ports, ds);
+ if (err)
+ return err;
+ } else {
+ err = dsa_parse_member(pdata, &tree, &index);
+ if (err)
+ return err;
+
+ err = dsa_parse_ports(pdata, ds);
+ if (err)
+ return err;
+ }

dst = dsa_get_dst(tree);
if (!dst) {
@@ -617,6 +682,7 @@ static int _dsa_register_switch(struct dsa_switch *ds, struct device *dev)

ds->dst = dst;
ds->index = index;
+ ds->cd = pdata;

/* Initialize the routing table */
for (i = 0; i < DSA_MAX_SWITCHES; ++i)
--
2.9.3