usb:gadget: USB Mass Storage Gadget support

This patch adds the USB Mass Storage Gadget to u-boot
New command called "ums" is implemented to provide access
to on-device embedded persistent memory.

USB Mass Storage is supposed to work on top of the USB
Gadget framework

Signed-off-by: Lukasz Majewski <l.majewski@samsung.com>
Signed-off-by: Piotr Wilczek <p.wilczek@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
CC: Marek Vasut <marek.vasut@gmail.com>
diff --git a/common/Makefile b/common/Makefile
index 08af1a8..1abf4ea 100644
--- a/common/Makefile
+++ b/common/Makefile
@@ -179,6 +179,7 @@
 COBJS-y += usb.o usb_hub.o
 COBJS-$(CONFIG_USB_STORAGE) += usb_storage.o
 endif
+COBJS-$(CONFIG_CMD_USB_MASS_STORAGE) += cmd_usb_mass_storage.o
 COBJS-$(CONFIG_CMD_XIMG) += cmd_ximg.o
 COBJS-$(CONFIG_YAFFS2) += cmd_yaffs2.o
 COBJS-$(CONFIG_CMD_SPL) += cmd_spl.o
diff --git a/common/cmd_usb_mass_storage.c b/common/cmd_usb_mass_storage.c
new file mode 100644
index 0000000..87a5f2f
--- /dev/null
+++ b/common/cmd_usb_mass_storage.c
@@ -0,0 +1,86 @@
+/*
+ * Copyright (C) 2011 Samsung Electronics
+ * Lukasz Majewski <l.majewski@samsung.com>
+ *
+ * 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 (at your option) 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., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <errno.h>
+#include <common.h>
+#include <command.h>
+#include <g_dnl.h>
+#include <usb_mass_storage.h>
+
+int do_usb_mass_storage(cmd_tbl_t *cmdtp, int flag,
+			       int argc, char * const argv[])
+{
+	char *ep;
+	unsigned int dev_num = 0, offset = 0, part_size = 0;
+	int rc;
+
+	struct ums_board_info *ums_info;
+	static char *s = "ums";
+
+	if (argc < 2) {
+		printf("usage: ums <dev> - e.g. ums 0\n");
+		return 0;
+	}
+
+	dev_num = (int)simple_strtoul(argv[1], &ep, 16);
+
+	if (dev_num) {
+		puts("\nSet eMMC device to 0! - e.g. ums 0\n");
+		goto fail;
+	}
+
+	board_usb_init();
+	ums_info = board_ums_init(dev_num, offset, part_size);
+
+	if (!ums_info) {
+		printf("MMC: %d -> NOT available\n", dev_num);
+		goto fail;
+	}
+	rc = fsg_init(ums_info);
+	if (rc) {
+		printf("cmd ums: fsg_init failed\n");
+		goto fail;
+	}
+
+	g_dnl_register(s);
+
+	while (1) {
+		/* Handle control-c and timeouts */
+		if (ctrlc()) {
+			printf("The remote end did not respond in time.\n");
+			goto exit;
+		}
+		usb_gadget_handle_interrupts();
+		/* Check if USB cable has been detached */
+		if (fsg_main_thread(NULL) == EIO)
+			goto exit;
+	}
+exit:
+	g_dnl_unregister();
+	return 0;
+
+fail:
+	return -1;
+}
+
+U_BOOT_CMD(ums, CONFIG_SYS_MAXARGS, 1, do_usb_mass_storage,
+	"Use the UMS [User Mass Storage]",
+	"ums - User Mass Storage Gadget"
+);