usb: ums: fix disk capacity miscalculation and code cleanup

This patch prevents:
- ums disk capacity miscalculation because of integer overflow

Changes v2:
- Prevents passing zero size disk capacity to ums gadget driver
- Change function ums_get_capacity() to ums_disk_init() and do ums disk
  initialization before gadget init
- Remove unnecessary code from mass storage driver

Signed-off-by: Przemyslaw Marczak <p.marczak@samsung.com>
Cc: Marek Vasut <marex@denx.de>

1 files changed, 3 insertions, 23 deletions

diff --git a/drivers/usb/gadget/storage_common.c b/drivers/usb/gadget/storage_common.c
index c2c5424..02803df 100644
--- a/drivers/usb/gadget/storage_common.c
+++ b/drivers/usb/gadget/storage_common.c
@@ -572,36 +572,16 @@ static struct usb_gadget_strings	fsg_stringtab = {
 static int fsg_lun_open(struct fsg_lun *curlun, const char *filename)
 {
 	int				ro;
-	int				rc = -EINVAL;
-	loff_t				size;
-	loff_t				num_sectors;
-	loff_t				min_sectors;
 
 	/* R/W if we can, R/O if we must */
 	ro = curlun->initially_ro;
 
-	ums->get_capacity(ums, &size);
-	if (size < 0) {
-		printf("unable to find file size: %s\n", filename);
-		rc = (int) size;
-		goto out;
-	}
-	num_sectors = size >> 9;	/* File size in 512-byte blocks */
-	min_sectors = 1;
-	if (num_sectors < min_sectors) {
-		printf("file too small: %s\n", filename);
-		rc = -ETOOSMALL;
-		goto out;
-	}
-
 	curlun->ro = ro;
-	curlun->file_length = size;
-	curlun->num_sectors = num_sectors;
+	curlun->file_length = ums->num_sectors << 9;
+	curlun->num_sectors = ums->num_sectors;
 	debug("open backing file: %s\n", filename);
-	rc = 0;
 
-out:
-	return rc;
+	return 0;
 }
 
 static void fsg_lun_close(struct fsg_lun *curlun)