mtd: ichxrom: maybe-uninitialized with gcc-4.9

pci_read_config_word() might fail and not initialize its output,
as pointed out by older versions of gcc when using the -Wmaybe-unintialized
flag:

drivers/mtd/maps/ichxrom.c: In function ‘ichxrom_cleanup’:
drivers/mtd/maps/ichxrom.c:63:2: error: ‘word’ is used uninitialized in this function [-Werror=uninitialized]

This is apparently a correct warning, though it does not show up
with newer compilers. Changing the code to not attempt to write
back uninitialized data into PCI config space is a correct
fix for the problem and avoids the warning.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Marek Vasut <marex@denx.de>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
This commit is contained in:
Arnd Bergmann 2016-10-24 17:28:35 +02:00 committed by Brian Norris
parent 6080ef6e7c
commit e70dda0868

View File

@ -57,10 +57,12 @@ static void ichxrom_cleanup(struct ichxrom_window *window)
{
struct ichxrom_map_info *map, *scratch;
u16 word;
int ret;
/* Disable writes through the rom window */
pci_read_config_word(window->pdev, BIOS_CNTL, &word);
pci_write_config_word(window->pdev, BIOS_CNTL, word & ~1);
ret = pci_read_config_word(window->pdev, BIOS_CNTL, &word);
if (!ret)
pci_write_config_word(window->pdev, BIOS_CNTL, word & ~1);
pci_dev_put(window->pdev);
/* Free all of the mtd devices */