mtd: Add a retlen parameter to _get_{fact,user}_prot_info

Signed-off-by: Christian Riesch <[e-mail]>
Cc: Artem Bityutskiy <[e-mail]>
Signed-off-by: Brian Norris <[e-mail]>

drivers/mtd/chips/cfi_cmdset_0001.c

···
 static int cfi_intelext_read_user_prot_reg (struct mtd_info *, loff_t, size_t, size_t *, u_char *);
 static int cfi_intelext_write_user_prot_reg (struct mtd_info *, loff_t, size_t, size_t *, u_char *);
 static int cfi_intelext_lock_user_prot_reg (struct mtd_info *, loff_t, size_t);
-static int cfi_intelext_get_fact_prot_info (struct mtd_info *,
-					    struct otp_info *, size_t);
-static int cfi_intelext_get_user_prot_info (struct mtd_info *,
-					    struct otp_info *, size_t);
+static int cfi_intelext_get_fact_prot_info(struct mtd_info *, size_t,
+					   size_t *, struct otp_info *);
+static int cfi_intelext_get_user_prot_info(struct mtd_info *, size_t,
+					   size_t *, struct otp_info *);
 #endif
 static int cfi_intelext_suspend (struct mtd_info *);
 static void cfi_intelext_resume (struct mtd_info *);
···
 				     NULL, do_otp_lock, 1);
 }
 
-static int cfi_intelext_get_fact_prot_info(struct mtd_info *mtd,
-					   struct otp_info *buf, size_t len)
-{
-	size_t retlen;
-	int ret;
+static int cfi_intelext_get_fact_prot_info(struct mtd_info *mtd, size_t len,
+					   size_t *retlen, struct otp_info *buf)
 
-	ret = cfi_intelext_otp_walk(mtd, 0, len, &retlen, (u_char *)buf, NULL, 0);
-	return ret ? : retlen;
+{
+	return cfi_intelext_otp_walk(mtd, 0, len, retlen, (u_char *)buf,
+				     NULL, 0);
 }
 
-static int cfi_intelext_get_user_prot_info(struct mtd_info *mtd,
-					   struct otp_info *buf, size_t len)
+static int cfi_intelext_get_user_prot_info(struct mtd_info *mtd, size_t len,
+					   size_t *retlen, struct otp_info *buf)
 {
-	size_t retlen;
-	int ret;
-
-	ret = cfi_intelext_otp_walk(mtd, 0, len, &retlen, (u_char *)buf, NULL, 1);
-	return ret ? : retlen;
+	return cfi_intelext_otp_walk(mtd, 0, len, retlen, (u_char *)buf,
+				     NULL, 1);
 }
 
 #endif

drivers/mtd/devices/mtd_dataflash.c

···
 
 #ifdef CONFIG_MTD_DATAFLASH_OTP
 
-static int dataflash_get_otp_info(struct mtd_info *mtd,
-		struct otp_info *info, size_t len)
+static int dataflash_get_otp_info(struct mtd_info *mtd, size_t len,
+				  size_t *retlen, struct otp_info *info)
 {
 	/* Report both blocks as identical:  bytes 0..64, locked.
 	 * Unless the user block changed from all-ones, we can't
···
 	info->start = 0;
 	info->length = 64;
 	info->locked = 1;
-	return sizeof(*info);
+	*retlen = sizeof(*info);
+	return 0;
 }
 
 static ssize_t otp_read(struct spi_device *spi, unsigned base,

drivers/mtd/mtdchar.c

···
 	case OTPGETREGIONINFO:
 	{
 		struct otp_info *buf = kmalloc(4096, GFP_KERNEL);
+		size_t retlen;
 		if (!buf)
 			return -ENOMEM;
 		switch (mfi->mode) {
 		case MTD_FILE_MODE_OTP_FACTORY:
-			ret = mtd_get_fact_prot_info(mtd, buf, 4096);
+			ret = mtd_get_fact_prot_info(mtd, 4096, &retlen, buf);
 			break;
 		case MTD_FILE_MODE_OTP_USER:
-			ret = mtd_get_user_prot_info(mtd, buf, 4096);
+			ret = mtd_get_user_prot_info(mtd, 4096, &retlen, buf);
 			break;
 		default:
 			ret = -EINVAL;
 			break;
 		}
-		if (ret >= 0) {
+		if (!ret) {
 			if (cmd == OTPGETREGIONCOUNT) {
-				int nbr = ret / sizeof(struct otp_info);
+				int nbr = retlen / sizeof(struct otp_info);
 				ret = copy_to_user(argp, &nbr, sizeof(int));
 			} else
-				ret = copy_to_user(argp, buf, ret);
+				ret = copy_to_user(argp, buf, retlen);
 			if (ret)
 				ret = -EFAULT;
 		}

drivers/mtd/mtdcore.c

···
  * devices. The user data is one time programmable but the factory data is read
  * only.
  */
-int mtd_get_fact_prot_info(struct mtd_info *mtd, struct otp_info *buf,
-			   size_t len)
+int mtd_get_fact_prot_info(struct mtd_info *mtd, size_t len, size_t *retlen,
+			   struct otp_info *buf)
 {
 	if (!mtd->_get_fact_prot_info)
 		return -EOPNOTSUPP;
 	if (!len)
 		return 0;
-	return mtd->_get_fact_prot_info(mtd, buf, len);
+	return mtd->_get_fact_prot_info(mtd, len, retlen, buf);
 }
 EXPORT_SYMBOL_GPL(mtd_get_fact_prot_info);
 
···
 }
 EXPORT_SYMBOL_GPL(mtd_read_fact_prot_reg);
 
-int mtd_get_user_prot_info(struct mtd_info *mtd, struct otp_info *buf,
-			   size_t len)
+int mtd_get_user_prot_info(struct mtd_info *mtd, size_t len, size_t *retlen,
+			   struct otp_info *buf)
 {
 	if (!mtd->_get_user_prot_info)
 		return -EOPNOTSUPP;
 	if (!len)
 		return 0;
-	return mtd->_get_user_prot_info(mtd, buf, len);
+	return mtd->_get_user_prot_info(mtd, len, retlen, buf);
 }
 EXPORT_SYMBOL_GPL(mtd_get_user_prot_info);
 

drivers/mtd/mtdpart.c

···
 						 retlen, buf);
 }
 
-static int part_get_user_prot_info(struct mtd_info *mtd,
-		struct otp_info *buf, size_t len)
+static int part_get_user_prot_info(struct mtd_info *mtd, size_t len,
+				   size_t *retlen, struct otp_info *buf)
 {
 	struct mtd_part *part = PART(mtd);
-	return part->master->_get_user_prot_info(part->master, buf, len);
+	return part->master->_get_user_prot_info(part->master, len, retlen,
+						 buf);
 }
 
 static int part_read_fact_prot_reg(struct mtd_info *mtd, loff_t from,
···
 						 retlen, buf);
 }
 
-static int part_get_fact_prot_info(struct mtd_info *mtd, struct otp_info *buf,
-		size_t len)
+static int part_get_fact_prot_info(struct mtd_info *mtd, size_t len,
+				   size_t *retlen, struct otp_info *buf)
 {
 	struct mtd_part *part = PART(mtd);
-	return part->master->_get_fact_prot_info(part->master, buf, len);
+	return part->master->_get_fact_prot_info(part->master, len, retlen,
+						 buf);
 }
 
 static int part_write(struct mtd_info *mtd, loff_t to, size_t len,

drivers/mtd/onenand/onenand_base.c

···
 /**
  * onenand_get_fact_prot_info - [MTD Interface] Read factory OTP info
  * @param mtd		MTD device structure
- * @param buf		the databuffer to put/get data
  * @param len		number of bytes to read
+ * @param retlen	pointer to variable to store the number of read bytes
+ * @param buf		the databuffer to put/get data
  *
  * Read factory OTP info.
  */
-static int onenand_get_fact_prot_info(struct mtd_info *mtd,
-			struct otp_info *buf, size_t len)
+static int onenand_get_fact_prot_info(struct mtd_info *mtd, size_t len,
+				      size_t *retlen, struct otp_info *buf)
 {
-	size_t retlen;
-	int ret;
-
-	ret = onenand_otp_walk(mtd, 0, len, &retlen, (u_char *) buf, NULL, MTD_OTP_FACTORY);
-
-	return ret ? : retlen;
+	return onenand_otp_walk(mtd, 0, len, retlen, (u_char *) buf, NULL,
+				MTD_OTP_FACTORY);
 }
 
 /**
···
 /**
  * onenand_get_user_prot_info - [MTD Interface] Read user OTP info
  * @param mtd		MTD device structure
- * @param buf		the databuffer to put/get data
+ * @param retlen	pointer to variable to store the number of read bytes
  * @param len		number of bytes to read
+ * @param buf		the databuffer to put/get data
  *
  * Read user OTP info.
  */
-static int onenand_get_user_prot_info(struct mtd_info *mtd,
-			struct otp_info *buf, size_t len)
+static int onenand_get_user_prot_info(struct mtd_info *mtd, size_t len,
+				      size_t *retlen, struct otp_info *buf)
 {
-	size_t retlen;
-	int ret;
-
-	ret = onenand_otp_walk(mtd, 0, len, &retlen, (u_char *) buf, NULL, MTD_OTP_USER);
-
-	return ret ? : retlen;
+	return onenand_otp_walk(mtd, 0, len, retlen, (u_char *) buf, NULL,
+				MTD_OTP_USER);
 }
 
 /**

include/linux/mtd/mtd.h

···
 			  struct mtd_oob_ops *ops);
 	int (*_write_oob) (struct mtd_info *mtd, loff_t to,
 			   struct mtd_oob_ops *ops);
-	int (*_get_fact_prot_info) (struct mtd_info *mtd, struct otp_info *buf,
-				    size_t len);
+	int (*_get_fact_prot_info) (struct mtd_info *mtd, size_t len,
+				    size_t *retlen, struct otp_info *buf);
 	int (*_read_fact_prot_reg) (struct mtd_info *mtd, loff_t from,
 				    size_t len, size_t *retlen, u_char *buf);
-	int (*_get_user_prot_info) (struct mtd_info *mtd, struct otp_info *buf,
-				    size_t len);
+	int (*_get_user_prot_info) (struct mtd_info *mtd, size_t len,
+				    size_t *retlen, struct otp_info *buf);
 	int (*_read_user_prot_reg) (struct mtd_info *mtd, loff_t from,
 				    size_t len, size_t *retlen, u_char *buf);
 	int (*_write_user_prot_reg) (struct mtd_info *mtd, loff_t to,
···
 	return mtd->_write_oob(mtd, to, ops);
 }
 
-int mtd_get_fact_prot_info(struct mtd_info *mtd, struct otp_info *buf,
-			   size_t len);
+int mtd_get_fact_prot_info(struct mtd_info *mtd, size_t len, size_t *retlen,
+			   struct otp_info *buf);
 int mtd_read_fact_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
 			   size_t *retlen, u_char *buf);
-int mtd_get_user_prot_info(struct mtd_info *mtd, struct otp_info *buf,
-			   size_t len);
+int mtd_get_user_prot_info(struct mtd_info *mtd, size_t len, size_t *retlen,
+			   struct otp_info *buf);
 int mtd_read_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
 			   size_t *retlen, u_char *buf);
 int mtd_write_user_prot_reg(struct mtd_info *mtd, loff_t to, size_t len,