mtd: fix hang-up in cfi erase and read contention

cfi erase command hangs up when erase and read contention occurs.
If read runs at the same address as erase operation, read issues
Erase-Suspend via get_chip() and the erase goes into sleep in wait queue.
But in this case, read operation exits by time-out without waking it up.

I think the other variants (0001, 0020 and lpddr) have the same problem too.
Tested and verified the patch only on CFI-0002 flash, though.

Signed-off-by: Tadashi Abe <tabe@mvista.com>
Acked-by: Joakim Tjernlund <joakim.tjernlund@transmode.se>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/mtd/chips/cfi_cmdset_0020.c b/drivers/mtd/chips/cfi_cmdset_0020.c
index ed56ad3884fb..179814a95f3a 100644
--- a/drivers/mtd/chips/cfi_cmdset_0020.c
+++ b/drivers/mtd/chips/cfi_cmdset_0020.c
@@ -296,6 +296,7 @@ static inline int do_read_onechip(struct map_info *map, struct flchip *chip, lof
                                 /* make sure we're in 'read status' mode */
                                 map_write(map, CMD(0x70), cmd_addr);
                                 chip->state = FL_ERASING;
+                                wake_up(&chip->wq);
                                 mutex_unlock(&chip->mutex);
                                 printk(KERN_ERR "Chip not ready after erase "
                                        "suspended: status = 0x%lx\n", status.x[0]);