net: introduce per device index

Instead of counting the device index everytime a functions needs it, store
it in the eth_device struct. eth_register() keeps track of the indices and
updates the device's index number. This simplifies some functions in
net/eth.c.

Additionally, a network driver can now query its index, eg. to get the
correct environment ethaddr name.

Signed-off-by: Michael Walle <michael@walle.cc>
Cc: Prafulla Wadaskar <prafulla@marvell.com>
Cc: Mike Frysinger <vapier@gentoo.com>
Cc: Wolfgang Denk <wd@denx.de>
Acked-by: Mike Frysinger <vapier@gentoo.org>

include/net.h

@@ -90,6 +90,7 @@ struct eth_device {
 #endif
 	int  (*write_hwaddr) (struct eth_device*);
 	struct eth_device *next;
+	int index;
 	void *priv;
 };
 

net/eth.c

@@ -127,7 +127,6 @@ struct eth_device *eth_get_dev_by_name(const char *devname)
 struct eth_device *eth_get_dev_by_index(int index)
 {
 	struct eth_device *dev, *target_dev;
-	int idx = 0;
 
 	if (!eth_devices)
 		return NULL;
@@ -135,12 +134,11 @@ struct eth_device *eth_get_dev_by_index(int index)
 	dev = eth_devices;
 	target_dev = NULL;
 	do {
-		if (idx == index) {
+		if (dev->index == index) {
 			target_dev = dev;
 			break;
 		}
 		dev = dev->next;
-		idx++;
 	} while (dev != eth_devices);
 
 	return target_dev;
@@ -148,24 +146,11 @@ struct eth_device *eth_get_dev_by_index(int index)
 
 int eth_get_dev_index (void)
 {
-	struct eth_device *dev;
-	int num = 0;
-
-	if (!eth_devices) {
-		return (-1);
-	}
-
-	for (dev = eth_devices; dev; dev = dev->next) {
-		if (dev == eth_current)
-			break;
-		++num;
-	}
-
-	if (dev) {
-		return (num);
+	if (!eth_current) {
+		return -1;
 	}
 
-	return (0);
+	return eth_current->index;
 }
 
 static void eth_current_changed(void)
@@ -219,6 +204,7 @@ int eth_write_hwaddr(struct eth_device *dev, const char *base_name,
 int eth_register(struct eth_device *dev)
 {
 	struct eth_device *d;
+	static int index = 0;
 
 	assert(strlen(dev->name) < NAMESIZE);
 
@@ -233,14 +219,14 @@ int eth_register(struct eth_device *dev)
 
 	dev->state = ETH_STATE_INIT;
 	dev->next  = eth_devices;
+	dev->index = index++;
 
 	return 0;
 }
 
 int eth_initialize(bd_t *bis)
 {
-	int eth_number = 0;
-
+	int num_devices = 0;
 	eth_devices = NULL;
 	eth_current = NULL;
 
@@ -281,7 +267,7 @@ int eth_initialize(bd_t *bis)
 
 		show_boot_progress (65);
 		do {
-			if (eth_number)
+			if (dev->index)
 				puts (", ");
 
 			printf("%s", dev->name);
@@ -294,18 +280,18 @@ int eth_initialize(bd_t *bis)
 			if (strchr(dev->name, ' '))
 				puts("\nWarning: eth device name has a space!\n");
 
-			if (eth_write_hwaddr(dev, "eth", eth_number))
+			if (eth_write_hwaddr(dev, "eth", dev->index))
 				puts("\nWarning: failed to set MAC address\n");
 
-			eth_number++;
 			dev = dev->next;
+			num_devices++;
 		} while(dev != eth_devices);
 
 		eth_current_changed();
 		putc ('\n');
 	}
 
-	return eth_number;
+	return num_devices;
 }
 
 #ifdef CONFIG_MCAST_TFTP
@@ -356,7 +342,6 @@ u32 ether_crc (size_t len, unsigned char const *p)
 
 int eth_init(bd_t *bis)
 {
-	int eth_number;
 	struct eth_device *old_current, *dev;
 
 	if (!eth_current) {
@@ -365,16 +350,14 @@ int eth_init(bd_t *bis)
 	}
 
 	/* Sync environment with network devices */
-	eth_number = 0;
 	dev = eth_devices;
 	do {
 		uchar env_enetaddr[6];
 
-		if (eth_getenv_enetaddr_by_index("eth", eth_number,
+		if (eth_getenv_enetaddr_by_index("eth", dev->index,
 						 env_enetaddr))
 			memcpy(dev->enetaddr, env_enetaddr, 6);
 
-		++eth_number;
 		dev = dev->next;
 	} while (dev != eth_devices);