usb: ums: code refactoring to improve reusability on other boards.

This patch introduces some cleanups to ums code. Changes:

ums common:
- introduce UMS_START_SECTOR and UMS_NUM_SECTORS as defined in
  usb_mass_storage.h both default values as 0 if board config
  doesn't define them

common cleanup changes:
- change name of struct "ums_board_info" to "ums"
- "ums_device" fields are moved to struct ums and "dev_num" is removed
- change function name: board_ums_init to ums_init
- remove "extern" prefixes from usb_mass_storage.h

cmd_usb_mass_storage:
- change error() to printf() if need to print info message
- change return values to command_ret_t type at ums command code
- add command usage string

Changes v2:
ums common:
- always returns number of read/write sectors
- coding style clean-up
ums gadget:
- calculate amount of read/write from device returned value.

Signed-off-by: Przemyslaw Marczak <p.marczak@samsung.com>
Cc: Marek Vasut <marek.vasut@gmail.com>

2 files changed, 23 insertions, 23 deletions

diff --git a/drivers/usb/gadget/f_mass_storage.c b/drivers/usb/gadget/f_mass_storage.c
index 6ecdea3..be6b418 100644
--- a/drivers/usb/gadget/f_mass_storage.c
+++ b/drivers/usb/gadget/f_mass_storage.c
@@ -441,7 +441,7 @@ static void set_bulk_out_req_length(struct fsg_common *common,
 
 /*-------------------------------------------------------------------------*/
 
-struct ums_board_info			*ums_info;
+struct ums *ums;
 struct fsg_common *the_fsg_common;
 
 static int fsg_set_halt(struct fsg_dev *fsg, struct usb_ep *ep)
@@ -757,14 +757,14 @@ static int do_read(struct fsg_common *common)
 		}
 
 		/* Perform the read */
-		nread = 0;
-		rc = ums_info->read_sector(&(ums_info->ums_dev),
-					   file_offset / SECTOR_SIZE,
-					   amount / SECTOR_SIZE,
-					   (char __user *)bh->buf);
-		if (rc)
+		rc = ums->read_sector(ums,
+				      file_offset / SECTOR_SIZE,
+				      amount / SECTOR_SIZE,
+				      (char __user *)bh->buf);
+		if (!rc)
 			return -EIO;
-		nread = amount;
+
+		nread = rc * SECTOR_SIZE;
 
 		VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
 				(unsigned long long) file_offset,
@@ -931,13 +931,13 @@ static int do_write(struct fsg_common *common)
 			amount = bh->outreq->actual;
 
 			/* Perform the write */
-			rc = ums_info->write_sector(&(ums_info->ums_dev),
+			rc = ums->write_sector(ums,
 					       file_offset / SECTOR_SIZE,
 					       amount / SECTOR_SIZE,
 					       (char __user *)bh->buf);
-			if (rc)
+			if (!rc)
 				return -EIO;
-			nwritten = amount;
+			nwritten = rc * SECTOR_SIZE;
 
 			VLDBG(curlun, "file write %u @ %llu -> %d\n", amount,
 					(unsigned long long) file_offset,
@@ -959,6 +959,8 @@ static int do_write(struct fsg_common *common)
 
 			/* If an error occurred, report it and its position */
 			if (nwritten < amount) {
+				printf("nwritten:%d amount:%d\n", nwritten,
+				       amount);
 				curlun->sense_data = SS_WRITE_ERROR;
 				curlun->info_valid = 1;
 				break;
@@ -1045,14 +1047,13 @@ static int do_verify(struct fsg_common *common)
 		}
 
 		/* Perform the read */
-		nread = 0;
-		rc = ums_info->read_sector(&(ums_info->ums_dev),
-					   file_offset / SECTOR_SIZE,
-					   amount / SECTOR_SIZE,
-					   (char __user *)bh->buf);
-		if (rc)
+		rc = ums->read_sector(ums,
+				      file_offset / SECTOR_SIZE,
+				      amount / SECTOR_SIZE,
+				      (char __user *)bh->buf);
+		if (!rc)
 			return -EIO;
-		nread = amount;
+		nread = rc * SECTOR_SIZE;
 
 		VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
 				(unsigned long long) file_offset,
@@ -1100,7 +1101,7 @@ static int do_inquiry(struct fsg_common *common, struct fsg_buffhd *bh)
 	buf[4] = 31;		/* Additional length */
 				/* No special options */
 	sprintf((char *) (buf + 8), "%-8s%-16s%04x", (char*) vendor_id ,
-			ums_info->name, (u16) 0xffff);
+			ums->name, (u16) 0xffff);
 
 	return 36;
 }
@@ -2753,9 +2754,9 @@ int fsg_add(struct usb_configuration *c)
 	return fsg_bind_config(c->cdev, c, fsg_common);
 }
 
-int fsg_init(struct ums_board_info *ums)
+int fsg_init(struct ums *ums_dev)
 {
-	ums_info = ums;
+	ums = ums_dev;
 
 	return 0;
 }
diff --git a/drivers/usb/gadget/storage_common.c b/drivers/usb/gadget/storage_common.c
index 866e7c7..c2c5424 100644
--- a/drivers/usb/gadget/storage_common.c
+++ b/drivers/usb/gadget/storage_common.c
@@ -275,7 +275,6 @@ struct rw_semaphore { int i; };
 #define ETOOSMALL	525
 
 #include <usb_mass_storage.h>
-extern struct ums_board_info		*ums_info;
 
 /*-------------------------------------------------------------------------*/
 
@@ -581,7 +580,7 @@ static int fsg_lun_open(struct fsg_lun *curlun, const char *filename)
 	/* R/W if we can, R/O if we must */
 	ro = curlun->initially_ro;
 
-	ums_info->get_capacity(&(ums_info->ums_dev), &size);
+	ums->get_capacity(ums, &size);
 	if (size < 0) {
 		printf("unable to find file size: %s\n", filename);
 		rc = (int) size;