omap hsmmc: fix a racing case between kmmcd and omap_hsmmc_suspend
authorEthan Du <ethan.too@gmail.com>
Thu, 9 Sep 2010 23:37:49 +0000 (16:37 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Fri, 10 Sep 2010 01:57:23 +0000 (18:57 -0700)
If suspend called when kmmcd is doing host->ops->disable, as kmmcd already
increased host->en_dis_recurs to 1, the mmc_host_enable in suspend
function will return directly without increase the nesting_cnt, which will
cause the followed register access carried out to the disabled host.

mmc_suspend_host will enable host itself.  No need to enable host before
it.  Also works on kmmcd will get flushed in mmc_suspend_host, enable host
after it will be safe.  So make the mmc_host_enable after it.

[cjb: rebase against current Linus]
Signed-off-by: Ethan <ethan.too@gmail.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
Acked-by: Adrian Hunter <adrian.hunter@nokia.com>
Acked-by: Madhusudhan Chikkature <madhu.cr@ti.com>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drivers/mmc/host/omap_hsmmc.c

index fb6446a6fb4d2caede2894dcafc2920d1be9e65d..4526d2791f2990229acbe9ef0f5c88286819807f 100644 (file)
@@ -2323,8 +2323,8 @@ static int omap_hsmmc_suspend(struct device *dev)
                        }
                }
                cancel_work_sync(&host->mmc_carddetect_work);
-               mmc_host_enable(host->mmc);
                ret = mmc_suspend_host(host->mmc);
+               mmc_host_enable(host->mmc);
                if (ret == 0) {
                        omap_hsmmc_disable_irq(host);
                        OMAP_HSMMC_WRITE(host->base, HCTL,