Merge pull request #1 from westermo/basic-help

Basic help

README.md

@@ -2,3 +2,49 @@ phytool
 =======
 
 Linux MII register access
+
+
+Usage
+-----
+
+    phytool read  iface/phy/reg
+	phytool write iface/phy/reg val
+    phytool print iface/phy[/reg]
+
+    The PHY argument is either in clause-22 direct adressing syntax, or in
+    clause-45 syntax `port:dev`. Where `port` is the MDIO port address and
+    `dev` is the device's PHY address (0x1-0xA), MAC register (0x10-0x1A),
+    the global register (0x1B), or the global2 register (0x1C)
+
+    Some devices have a SERDES specific page on `dev` address 0xF
+
+
+Examples
+--------
+
+    ~ # phytool read eth4/0/4
+    0x0de1
+
+    ~ # phytool print eth4/0
+    ieee-phy: id:0x01410eb1
+
+       ieee-phy: reg:BMCR(0x00) val:0x0800
+          flags: reset loopback aneg-enable power-down isolate aneg-restart collision-test
+          speed: 10-half
+          ○ ○ ○ ○  ◉ ○ ○ ○  ○ ○ ○ ○  ○ ○ ○ ○
+             0        8        0        0
+
+       ieee-phy: reg:BMSR(0x01) val:0x7949
+          link capabilities: 100-b4 100-f 100-h 10-f 10-h 100-t2-f 100-t2-h
+          flags: ext-status aneg-complete remote-fault aneg-capable link jabber ext-register
+          ○ ◉ ◉ ◉  ◉ ○ ○ ◉  ○ ◉ ○ ○  ◉ ○ ○ ◉
+             7        9        4        9
+
+
+Origin & References
+-------------------
+
+phytool is developed and maintained by Tobias Waldekranz.  
+Please file bug fixes and pull requests at [GitHub][]
+
+[GitHub]: https://github.com/wkz/phytool

phytool.c

@@ -33,6 +33,9 @@
 
 #include "phytool.h"
 
+extern char *__progname;
+
+
 static int __phy_op(const struct loc *loc, uint16_t *val, int cmd)
 {
 	static int sd = -1;
@@ -227,17 +230,39 @@ static struct printer printer[] = {
 	{ .name = NULL }
 };
 
+static int usage(int code)
+{
+	printf("\nUsage:\n"
+	       "\t%s read  iface/phy/reg\n"
+	       "\t%s write iface/phy/reg val\n"
+	       "\t%s print iface/phy[/reg]\n"
+	       "\nExamples:\n"
+	       "\t%s read  eth0/0/4\n"
+	       "\t%s read  eth1-2/1:0x10/4\n"
+	       "\t%s print eth1-2/1:0x10\n"
+	       "\n"
+	       "The PHY argument is either in clause-22 direct adressing syntax, or in\n"
+	       "clause-45 syntax `port:dev`. Where `port` is the MDIO port address and\n"
+	       "`dev` is the device's PHY address (0x0-0xA), MAC register (0x10-0x1A),\n"
+	       "the global register (0x1B), or the global2 register (0x1C).\n\n"
+	       "Some devices have a SERDES specific page on `dev` address 0xF.\n\n"
+	       "Bug report address: https://github.com/wkz/phytool/issues\n\n",
+	       __progname, __progname, __progname, __progname, __progname, __progname);
+
+	return code;
+}
+
 int main(int argc, char **argv)
 {
-	char *bin = basename(argv[0]);
 	struct printer *p;
 
 	if (argc < 2)
-		return 1;
+		return usage(1);
 
-	for (p = printer; p->name; p++)
-		if (!strcmp(bin, p->name))
+	for (p = printer; p->name; p++) {
+		if (!strcmp(__progname, p->name))
 			break;
+	}
 
 	if (!p->name)
 		p = printer;
@@ -250,5 +275,5 @@ int main(int argc, char **argv)
 		return phytool_print(p->print, argc - 2, &argv[2]);
 
 	fprintf(stderr, "error: unknown command \"%s\"\n", argv[1]);
-	return 1;
+	return usage(1);
 }