[usb] Add "usbscan" command for iterating over USB devices

Implement a "usbscan" command as a direct analogy of the existing
"pciscan" command, allowing scripts to iterate over all detected USB
devices.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

1 files changed, 122 insertions, 0 deletions

diff --git a/src/hci/commands/usb_cmd.c b/src/hci/commands/usb_cmd.c
new file mode 100644
index 000000000..d1086fd7e
--- /dev/null
+++ b/src/hci/commands/usb_cmd.c
@@ -0,0 +1,122 @@
+/*
+ * Copyright (C) 2024 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ *
+ * You can also choose to distribute this program under the terms of
+ * the Unmodified Binary Distribution Licence (as given in the file
+ * COPYING.UBDL), provided that you have satisfied its requirements.
+ */
+
+#include <stdio.h>
+#include <errno.h>
+#include <getopt.h>
+#include <ipxe/usb.h>
+#include <ipxe/command.h>
+#include <ipxe/parseopt.h>
+
+FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
+
+/** @file
+ *
+ * USB commands
+ *
+ */
+
+/** "usbscan" options */
+struct usbscan_options {};
+
+/** "usbscan" option list */
+static struct option_descriptor usbscan_opts[] = {};
+
+/** "usbscan" command descriptor */
+static struct command_descriptor usbscan_cmd =
+	COMMAND_DESC ( struct usbscan_options, usbscan_opts, 1, 1,
+		       "<setting>" );
+
+/**
+ * "usbscan" command
+ *
+ * @v argc		Argument count
+ * @v argv		Argument list
+ * @ret rc		Return status code
+ */
+static int usbscan_exec ( int argc, char **argv ) {
+	struct usbscan_options opts;
+	struct named_setting setting;
+	struct usb_device *usb;
+	unsigned long prev;
+	uint16_t busdev;
+	int len;
+	int rc;
+
+	/* Parse options */
+	if ( ( rc = parse_options ( argc, argv, &usbscan_cmd, &opts ) ) != 0 )
+		goto err_parse_options;
+
+	/* Parse setting name */
+	if ( ( rc = parse_autovivified_setting ( argv[optind],
+						 &setting ) ) != 0 )
+		goto err_parse_setting;
+
+	/* Determine starting bus:dev.fn address */
+	if ( ( len = fetchn_setting ( setting.settings, &setting.setting,
+				      NULL, &setting.setting, &prev ) ) < 0 ) {
+		/* Setting not yet defined: start searching from 00:00 */
+		busdev = 0;
+	} else {
+		/* Setting is defined: start searching from next location */
+		busdev = ( prev + 1 );
+		if ( ! busdev ) {
+			rc = -ENOENT;
+			goto err_end;
+		}
+	}
+
+	/* Find next existent USB device */
+	if ( ( rc = usb_find_next ( &usb, &busdev ) ) != 0 )
+		goto err_find_next;
+
+	/* Apply default type if necessary.  Use ":uint16" rather than
+	 * ":hex" to allow for easy inclusion within a
+	 * "${usb/${location}....}" constructed setting.
+	 */
+	if ( ! setting.setting.type )
+		setting.setting.type = &setting_type_uint16;
+
+	/* Store setting */
+	if ( ( rc = storen_setting ( setting.settings, &setting.setting,
+				     busdev ) ) != 0 ) {
+		printf ( "Could not store \"%s\": %s\n",
+			 setting.setting.name, strerror ( rc ) );
+		goto err_store;
+	}
+
+ err_store:
+ err_end:
+ err_find_next:
+ err_parse_setting:
+ err_parse_options:
+	return rc;
+}
+
+/** USB commands */
+struct command usb_commands[] __command = {
+	{
+		.name = "usbscan",
+		.exec = usbscan_exec,
+	},
+};