gsctool: use the usb serial number to find the usb device

Add a serial number arg that can be used to specify which CCD device to
use. If there are multiple CCD devices, you can use this arg to pick
which device to update.

BUG=none
BRANCH=none
TEST='gsctool -f -n $SERIAL' can be used to get the cr50 version from
two chromebooks connected to the same machine. 'gsctool -f' still works
too.

Change-Id: I91cbfdc7d62bee2623919e4dded62f92ba7adb19
Signed-off-by: Mary Ruthven <mruthven@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/1600501
Reviewed-by: Vadim Bendebury <vbendeb@chromium.org>

1 files changed, 19 insertions, 3 deletions

diff --git a/extra/usb_updater/gsctool.c b/extra/usb_updater/gsctool.c
index c65234e305..8d7f884289 100644
--- a/extra/usb_updater/gsctool.c
+++ b/extra/usb_updater/gsctool.c
@@ -222,7 +222,7 @@ struct options_map {
 static int verbose_mode;
 static uint32_t protocol_version;
 static char *progname;
-static char *short_opts = "aBbcd:F:fhIikLMmO:oPpR:rS:stUuVvw";
+static char *short_opts = "aBbcd:F:fhIikLMmn:O:oPpR:rS:stUuVvw";
 static const struct option long_opts[] = {
 	/* name    hasarg *flag val */
 	{"any",		                0,   NULL, 'a'},
@@ -247,6 +247,7 @@ static const struct option long_opts[] = {
 	{"sn_bits",	                1,   NULL, 'S'},
 	{"sn_rma_inc",	                1,   NULL, 'R'},
 	{"systemdev",	                0,   NULL, 's'},
+	{"serial",	                1,   NULL, 'n'},
 	{"tpm_mode",                    2,   NULL, 'm'},
 	{"trunks_send",	                0,   NULL, 't'},
 	{"verbose",	                0,   NULL, 'V'},
@@ -570,6 +571,7 @@ static void usage(int errs)
 	       "Effective with -b, -f, -i, and -O.\n"
 	       "  -m,--tpm_mode [enable|disable]\n"
 	       "                           Change or query tpm_mode\n"
+	       "  -n,--serial SERIAL       Cr50 CCD serial number\n"
 	       "  -O,--openbox_rma <desc_file>\n"
 	       "                           Verify other device's RO integrity\n"
 	       "                           using information provided in "
@@ -2260,7 +2262,8 @@ int main(int argc, char *argv[])
 	int errorcnt;
 	uint8_t *data = 0;
 	size_t data_len = 0;
-	uint16_t vid = VID, pid = PID;
+	uint16_t vid = 0;
+	uint16_t pid = 0;
 	int i;
 	size_t j;
 	int transferred_sections = 0;
@@ -2289,6 +2292,7 @@ int main(int argc, char *argv[])
 	int factory_mode = 0;
 	char *factory_mode_arg;
 	char *tpm_mode_arg = NULL;
+	char *serial = NULL;
 	int sn_bits = 0;
 	uint8_t sn_bits_arg[SN_BITS_SIZE];
 	int sn_inc_rma = 0;
@@ -2395,6 +2399,9 @@ int main(int argc, char *argv[])
 				tpm_mode_arg = optarg;
 			}
 			break;
+		case 'n':
+			serial = optarg;
+			break;
 		case 'O':
 			openbox_desc_file = optarg;
 			break;
@@ -2482,6 +2489,15 @@ int main(int argc, char *argv[])
 	if (errorcnt)
 		usage(errorcnt);
 
+	/*
+	 * If no usb device information was given, default to the using cr50
+	 * vendor and product id to find the usb device.
+	 */
+	if (!serial && !vid && !pid) {
+		vid = VID;
+		pid = PID;
+	}
+
 	if ((bid_action == bid_none) &&
 	    !ccd_info &&
 	    !ccd_lock &&
@@ -2533,7 +2549,7 @@ int main(int argc, char *argv[])
 	}
 
 	if (td.ep_type == usb_xfer) {
-		if (usb_findit(NULL, vid, pid, USB_SUBCLASS_GOOGLE_CR50,
+		if (usb_findit(serial, vid, pid, USB_SUBCLASS_GOOGLE_CR50,
 			       USB_PROTOCOL_GOOGLE_CR50_NON_HC_FW_UPDATE,
 			       &td.uep))
 			exit(update_error);