stm32mp: stm32prog: handle interruption during the first enumeration

When an interruption is received during the first USB enumeration
used to received the FlashLayout, with handle ctrl-c, the second
enumeration is not needed and the result for stm32prog_usb_loop
is false (reset is not needed).

This patch avoids the need of a second ctrl to interrupt the command
stm32prog.

Signed-off-by: Patrick Delaunay <patrick.delaunay@foss.st.com>
Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com>
Signed-off-by: Patrice Chotard <patrice.chotard@foss.st.com>
diff --git a/arch/arm/mach-stm32mp/cmd_stm32prog/stm32prog_usb.c b/arch/arm/mach-stm32mp/cmd_stm32prog/stm32prog_usb.c
index 82b702f..a8b57c4 100644
--- a/arch/arm/mach-stm32mp/cmd_stm32prog/stm32prog_usb.c
+++ b/arch/arm/mach-stm32mp/cmd_stm32prog/stm32prog_usb.c
@@ -206,9 +206,12 @@
 	g_dnl_set_product(product);
 
 	if (stm32prog_data->phase == PHASE_FLASHLAYOUT) {
+		/* forget any previous Control C */
+		clear_ctrlc();
 		ret = run_usb_dnl_gadget(dev, "usb_dnl_dfu");
-		if (ret || stm32prog_data->phase != PHASE_FLASHLAYOUT)
-			return ret;
+		/* DFU reset received, no error or CtrlC */
+		if (ret || stm32prog_data->phase != PHASE_FLASHLAYOUT || had_ctrlc())
+			return ret; /* true = reset on DFU error */
 		/* prepare the second enumeration with the FlashLayout */
 		stm32prog_dfu_init(data);
 	}