mtd: remove the de-select chip code in nand_release_device()

The nand_get_device() does not select the chip, but nand_release_device()
does de-select the chip. It is really strange.

With the current code, nand_sync() will de-select the chip, even if the chip
has never been selected.

To make the balance of select/de-select chip, it's better to remove the
de-select chip code in nand_release_device() which makes the code more
clear.

Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

1 files changed, 25 insertions, 10 deletions

diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index 6eef7fbe8fdb..861a87d4d16b 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -130,15 +130,12 @@ static int check_offs_len(struct mtd_info *mtd,
  * nand_release_device - [GENERIC] release chip
  * @mtd: MTD device structure
  *
- * Deselect, release chip lock and wake up anyone waiting on the device.
+ * Release chip lock and wake up anyone waiting on the device.
  */
 static void nand_release_device(struct mtd_info *mtd)
 {
         struct nand_chip *chip = mtd->priv;
 
-        /* De-select the NAND device */
-        chip->select_chip(mtd, -1);
-
         /* Release the controller and the chip */
         spin_lock(&chip->controller->lock);
         chip->controller->active = NULL;
@@ -333,8 +330,10 @@ static int nand_block_bad(struct mtd_info *mtd, loff_t ofs, int getchip)
                 i++;
         } while (!res && i < 2 && (chip->bbt_options & NAND_BBT_SCAN2NDPAGE));
 
-        if (getchip)
+        if (getchip) {
+                chip->select_chip(mtd, -1);
                 nand_release_device(mtd);
+        }
 
         return res;
 }
@@ -952,6 +951,7 @@ int nand_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
         ret = __nand_unlock(mtd, ofs, len, 0);
 
 out:
+        chip->select_chip(mtd, -1);
         nand_release_device(mtd);
 
         return ret;
@@ -1016,6 +1016,7 @@ int nand_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
         ret = __nand_unlock(mtd, ofs, len, 0x1);
 
 out:
+        chip->select_chip(mtd, -1);
         nand_release_device(mtd);
 
         return ret;
@@ -1552,6 +1553,7 @@ static int nand_do_read_ops(struct mtd_info *mtd, loff_t from,
                         chip->select_chip(mtd, chipnr);
                 }
         }
+        chip->select_chip(mtd, -1);
 
         ops->retlen = ops->len - (size_t) readlen;
         if (oob)
@@ -1806,6 +1808,7 @@ static int nand_do_read_oob(struct mtd_info *mtd, loff_t from,
                         chip->select_chip(mtd, chipnr);
                 }
         }
+        chip->select_chip(mtd, -1);
 
         ops->oobretlen = ops->ooblen - readlen;
 
@@ -2188,8 +2191,10 @@ static int nand_do_write_ops(struct mtd_info *mtd, loff_t to,
         chip->select_chip(mtd, chipnr);
 
         /* Check, if it is write protected */
-        if (nand_check_wp(mtd))
-                return -EIO;
+        if (nand_check_wp(mtd)) {
+                ret = -EIO;
+                goto err_out;
+        }
 
         realpage = (int)(to >> chip->page_shift);
         page = realpage & chip->pagemask;
@@ -2201,8 +2206,10 @@ static int nand_do_write_ops(struct mtd_info *mtd, loff_t to,
                 chip->pagebuf = -1;
 
         /* Don't allow multipage oob writes with offset */
-        if (oob && ops->ooboffs && (ops->ooboffs + ops->ooblen > oobmaxlen))
-                return -EINVAL;
+        if (oob && ops->ooboffs && (ops->ooboffs + ops->ooblen > oobmaxlen)) {
+                ret = -EINVAL;
+                goto err_out;
+        }
 
         while (1) {
                 int bytes = mtd->writesize;
@@ -2253,6 +2260,9 @@ static int nand_do_write_ops(struct mtd_info *mtd, loff_t to,
         ops->retlen = ops->len - writelen;
         if (unlikely(oob))
                 ops->oobretlen = ops->ooblen;
+
+err_out:
+        chip->select_chip(mtd, -1);
         return ret;
 }
 
@@ -2379,8 +2389,10 @@ static int nand_do_write_oob(struct mtd_info *mtd, loff_t to,
         chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1);
 
         /* Check, if it is write protected */
-        if (nand_check_wp(mtd))
+        if (nand_check_wp(mtd)) {
+                chip->select_chip(mtd, -1);
                 return -EROFS;
+        }
 
         /* Invalidate the page cache, if we write to the cached page */
         if (page == chip->pagebuf)
@@ -2393,6 +2405,8 @@ static int nand_do_write_oob(struct mtd_info *mtd, loff_t to,
         else
                 status = chip->ecc.write_oob(mtd, chip, page & chip->pagemask);
 
+        chip->select_chip(mtd, -1);
+
         if (status)
                 return status;
 
@@ -2625,6 +2639,7 @@ erase_exit:
         ret = instr->state == MTD_ERASE_DONE ? 0 : -EIO;
 
         /* Deselect and wake up anyone waiting on the device */
+        chip->select_chip(mtd, -1);
         nand_release_device(mtd);
 
         /* Do call back function */