[PATCH 03/11 V2] staging: dgnc: missing NULL check for ioremap in dgnc_do_remap()

[Daeseok Youn]

The ioremap() function can be failed, so it need to have error
handling in dgnc_do_remap(). And also the return type of
dgnc_do_remap() should be changed from "void" to "int"

Signed-off-by: Daeseok Youn <daeseok.y...@gmail.com>
---
V2: the subject line was cut off, I put it completely.

 drivers/staging/dgnc/dgnc_driver.c | 31 +++++++++++++++++++++----------
 1 file changed, 21 insertions(+), 10 deletions(-)

diff --git a/drivers/staging/dgnc/dgnc_driver.c 
b/drivers/staging/dgnc/dgnc_driver.c
index c87b3de..58cebf4 100644
--- a/drivers/staging/dgnc/dgnc_driver.c
+++ b/drivers/staging/dgnc/dgnc_driver.c
@@ -43,7 +43,7 @@ static void           dgnc_cleanup_board(struct dgnc_board 
*brd);
 static void            dgnc_poll_handler(ulong dummy);
 static int             dgnc_init_one(struct pci_dev *pdev,
                                      const struct pci_device_id *ent);
-static void            dgnc_do_remap(struct dgnc_board *brd);
+static int             dgnc_do_remap(struct dgnc_board *brd);
 
 /*
  * File operations permitted on Control/Management major.
@@ -431,7 +431,10 @@ static int dgnc_found_board(struct pci_dev *pdev, int id)
                brd->bd_uart_offset = 0x8;
                brd->bd_dividend = 921600;
 
-               dgnc_do_remap(brd);
+               rc = dgnc_do_remap(brd);
+
+               if (rc < 0)
+                       goto failed;
 
                /* Get and store the board VPD, if it exists */
                brd->bd_ops->vpd(brd);
@@ -483,15 +486,17 @@ static int dgnc_found_board(struct pci_dev *pdev, int id)
                brd->bd_uart_offset = 0x200;
                brd->bd_dividend = 921600;
 
-               dgnc_do_remap(brd);
+               rc = dgnc_do_remap(brd);
 
-               if (brd->re_map_membase) {
-                       /* Read and store the dvid after remapping */
-                       brd->dvid = readb(brd->re_map_membase + 0x8D);
+               if (rc < 0)
+                       goto failed;
+
+               /* Read and store the dvid after remapping */
+               brd->dvid = readb(brd->re_map_membase + 0x8D);
+
+               /* Get and store the board VPD, if it exists */
+               brd->bd_ops->vpd(brd);
 
-                       /* Get and store the board VPD, if it exists */
-                       brd->bd_ops->vpd(brd);
-               }
                break;
 
        default:
@@ -566,9 +571,15 @@ static int dgnc_finalize_board_init(struct dgnc_board *brd)
 /*
  * Remap PCI memory.
  */
-static void dgnc_do_remap(struct dgnc_board *brd)
+static int dgnc_do_remap(struct dgnc_board *brd)
 {
+       int rc = 0;
+
        brd->re_map_membase = ioremap(brd->membase, 0x1000);
+       if (!brd->re_map_membase)
+               rc = -ENOMEM;
+
+       return rc;
 }
 
 /*
-- 
1.9.1