dfu: Provide means to find difference between dfu-util -e and -R

This commit provides distinction between DFU device detach and reset.
The -R behavior is preserved with proper handling of the dfu-util's -e
switch, which detach the DFU device.

By running dfu-util -e; one can force device to finish the execution of
dfu command on target and execute some other scripted commands.

Moreover, some naming has been changed - the dfu_reset() method now is known
as dfu_detach(). New name better reflects the purpose of the code.

It was also necessary to increase the number of usb_gadget_handle_interrupts()
calls since we also must wait for detection of the USB reset event.

Example usage:
1. -e (detach) switch
 dfu-util -a0 -D file1.bin;dfu-util -a3 -D uImage;dfu-util -e

 access to u-boot prompt.

2. -R (reset) switch
 dfu-util -a0 -D file1.bin;dfu-util -R -a3 -D uImage

 target board reset

Signed-off-by: Lukasz Majewski <l.majewski@samsung.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Tested-by: Stephen Warren <swarren@nvidia.com>

1 files changed, 19 insertions, 4 deletions

diff --git a/common/cmd_dfu.c b/common/cmd_dfu.c
index 2633b30e55..9e020b40be 100644
--- a/common/cmd_dfu.c
+++ b/common/cmd_dfu.c
@@ -15,6 +15,8 @@
 
 static int do_dfu(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 {
+	bool dfu_reset = false;
+
 	if (argc < 4)
 		return CMD_RET_USAGE;
 
@@ -36,17 +38,28 @@ static int do_dfu(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 
 	int controller_index = simple_strtoul(usb_controller, NULL, 0);
 	board_usb_init(controller_index, USB_INIT_DEVICE);
-
+	dfu_clear_detach();
 	g_dnl_register("usb_dnl_dfu");
 	while (1) {
-		if (dfu_reset())
+		if (dfu_detach()) {
+			/*
+			 * Check if USB bus reset is performed after detach,
+			 * which indicates that -R switch has been passed to
+			 * dfu-util. In this case reboot the device
+			 */
+			if (dfu_usb_get_reset()) {
+				dfu_reset = true;
+				goto exit;
+			}
+
 			/*
 			 * This extra number of usb_gadget_handle_interrupts()
 			 * calls is necessary to assure correct transmission
 			 * completion with dfu-util
 			 */
-			if (++i == 10)
+			if (++i == 10000)
 				goto exit;
+		}
 
 		if (ctrlc())
 			goto exit;
@@ -58,9 +71,11 @@ exit:
 done:
 	dfu_free_entities();
 
-	if (dfu_reset())
+	if (dfu_reset)
 		run_command("reset", 0);
 
+	dfu_clear_detach();
+
 	return ret;
 }