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, 26 insertions, 5 deletions

diff --git a/drivers/dfu/dfu.c b/drivers/dfu/dfu.c
index 3512b14..55e6a83 100644
--- a/drivers/dfu/dfu.c
+++ b/drivers/dfu/dfu.c
@@ -17,20 +17,41 @@
 #include <linux/list.h>
 #include <linux/compiler.h>
 
-static bool dfu_reset_request;
+static bool dfu_detach_request;
 static LIST_HEAD(dfu_list);
 static int dfu_alt_num;
 static int alt_num_cnt;
 static struct hash_algo *dfu_hash_algo;
 
-bool dfu_reset(void)
+/*
+ * The purpose of the dfu_usb_get_reset() function is to
+ * provide information if after USB_DETACH request
+ * being sent the dfu-util performed reset of USB
+ * bus.
+ *
+ * Described behaviour is the only way to distinct if
+ * user has typed -e (detach) or -R (reset) when invoking
+ * dfu-util command.
+ *
+ */
+__weak bool dfu_usb_get_reset(void)
+{
+	return true;
+}
+
+bool dfu_detach(void)
+{
+	return dfu_detach_request;
+}
+
+void dfu_trigger_detach(void)
 {
-	return dfu_reset_request;
+	dfu_detach_request = true;
 }
 
-void dfu_trigger_reset()
+void dfu_clear_detach(void)
 {
-	dfu_reset_request = true;
+	dfu_detach_request = false;
 }
 
 static int dfu_find_alt_num(const char *s)