[PATCH v1 8/8] ifup: optimize net boot time for USB ethernet adapters

[Oleksij Rempel]

On some boards, forcing detection of all device will take noticeable more
time. To reduce this time, we need to scan only for USB devices.

So, provide option do ifup by forcing only USB scan.

Signed-off-by: Oleksij Rempel <o.rempel at pengutronix.de>
---
 Documentation/user/networking.rst |  3 +++
 arch/arm/boards/skov-imx6/board.c |  2 +-
 include/net.h                     |  1 +
 net/ifup.c                        | 16 ++++++++++++++--
 4 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/Documentation/user/networking.rst b/Documentation/user/networking.rst
index 9231ebde56..18936ff169 100644
--- a/Documentation/user/networking.rst
+++ b/Documentation/user/networking.rst
@@ -55,6 +55,9 @@ device:
 |                              |              | detected automatically during start (i.e. for  |
 |                              |              | USB network adapters)                          |
 +------------------------------+--------------+------------------------------------------------+
+| global.net.ifup_detect_usb   | boolean      | Set to true if you use USB network adapter     |
+|                              |              | and global.net.ifup_force_detect is too slow.  |
++------------------------------+--------------+------------------------------------------------+
 
 The first step for networking is configuring the network device. The network
 device is usually ``eth0``. The current configuration can be viewed with the
diff --git a/arch/arm/boards/skov-imx6/board.c b/arch/arm/boards/skov-imx6/board.c
index 9a32e68f21..bd00c16157 100644
--- a/arch/arm/boards/skov-imx6/board.c
+++ b/arch/arm/boards/skov-imx6/board.c
@@ -626,7 +626,7 @@ no_switch:
 		pr_warn("Can't disable eth0\n");
 	}
 
-	globalvar_set("net.ifup_force_detect", "true");
+	globalvar_set("net.ifup_detect_usb", "true");
 
 	return 0;
 }
diff --git a/include/net.h b/include/net.h
index aad28e4f4c..15cd921f56 100644
--- a/include/net.h
+++ b/include/net.h
@@ -488,6 +488,7 @@ int net_icmp_send(struct net_connection *con, int len);
 void led_trigger_network(enum led_trigger trigger);
 
 #define IFUP_FLAG_FORCE		(1 << 0)
+#define IFUP_FLAG_USB		(1 << 1)
 
 int ifup_edev(struct eth_device *edev, unsigned flags);
 int ifup(const char *name, unsigned flags);
diff --git a/net/ifup.c b/net/ifup.c
index 1870f74017..5cb2b52716 100644
--- a/net/ifup.c
+++ b/net/ifup.c
@@ -20,6 +20,7 @@
 #include <globalvar.h>
 #include <magicvar.h>
 #include <linux/stat.h>
+#include <usb/usb.h>
 
 static int eth_discover(char *file)
 {
@@ -260,6 +261,7 @@ int ifdown(const char *ethname)
 }
 
 static int net_ifup_force_detect;
+static int net_ifup_detect_usb;
 
 int ifup_all(unsigned flags)
 {
@@ -282,6 +284,9 @@ int ifup_all(unsigned flags)
 
 	closedir(dir);
 
+	if ((flags & IFUP_FLAG_USB) || net_ifup_detect_usb)
+		usb_rescan();
+
 	if ((flags & IFUP_FLAG_FORCE) || net_ifup_force_detect ||
 	    list_empty(&netdev_list))
 		device_detect_all();
@@ -303,6 +308,7 @@ void ifdown_all(void)
 static int ifup_all_init(void)
 {
 	globalvar_add_simple_bool("net.ifup_force_detect", &net_ifup_force_detect);
+	globalvar_add_simple_bool("net.ifup_detect_usb", &net_ifup_detect_usb);
 
 	return 0;
 }
@@ -310,6 +316,8 @@ late_initcall(ifup_all_init);
 
 BAREBOX_MAGICVAR(global.net.ifup_force_detect,
                  "net: force detection of devices on ifup -a");
+BAREBOX_MAGICVAR(global.net.ifup_detect_usb,
+                 "net: scan usb without forcing detection of all devices on ifup -a");
 
 #if IS_ENABLED(CONFIG_NET_CMD_IFUP)
 
@@ -319,11 +327,14 @@ static int do_ifup(int argc, char *argv[])
 	unsigned flags = 0;
 	int all = 0;
 
-	while ((opt = getopt(argc, argv, "af")) > 0) {
+	while ((opt = getopt(argc, argv, "afu")) > 0) {
 		switch (opt) {
 		case 'f':
 			flags |= IFUP_FLAG_FORCE;
 			break;
+		case 'u':
+			flags |= IFUP_FLAG_USB;
+			break;
 		case 'a':
 			all = 1;
 			break;
@@ -348,12 +359,13 @@ BAREBOX_CMD_HELP_TEXT("")
 BAREBOX_CMD_HELP_TEXT("Options:")
 BAREBOX_CMD_HELP_OPT ("-a",  "bring up all interfaces")
 BAREBOX_CMD_HELP_OPT ("-f",  "Force. Configure even if ip already set")
+BAREBOX_CMD_HELP_OPT ("-u",  "Probe USB ")
 BAREBOX_CMD_HELP_END
 
 BAREBOX_CMD_START(ifup)
 	.cmd		= do_ifup,
 	BAREBOX_CMD_DESC("bring a network interface up")
-	BAREBOX_CMD_OPTS("[-af] [INTF]")
+	BAREBOX_CMD_OPTS("[-afu] [INTF]")
 	BAREBOX_CMD_GROUP(CMD_GRP_NET)
 	BAREBOX_CMD_COMPLETE(eth_complete)
 	BAREBOX_CMD_HELP(cmd_ifup_help)
-- 
2.30.2