From 22770de11cb13e7120f973bca6c800de371a6717 Mon Sep 17 00:00:00 2001 From: Kevin Hilman Date: Thu, 17 May 2012 14:52:56 -0700 Subject: [PATCH] gpio/omap: fix broken context restore for non-OFF mode transitions The fix in commit 1b1287032 (gpio/omap: fix missing check in *_runtime_suspend()) exposed another bug in the context restore path. Currently, the per-bank context restore happens whenever the context loss count is different in runtime suspend and runtime resume *and* whenever the per-bank contex_loss_count == 0: if (context_lost_cnt_after != bank->context_loss_count || !context_lost_cnt_after) { omap_gpio_restore_context(bank); Restoring context when the context_lost_cnt_after == 0 is clearly wrong, since this will be true until the first off-mode transition (which could be never, if off-mode is never enabled.) This check causes the context to be restored on *every* runtime PM transition. Before commit 1b1287032 (gpio/omap: fix missing check in *_runtime_suspend()), this code was never executed in non-OFF mode, so there were never spurious context restores happening. After that change though, spurious context restores could happen. To fix, simply remove the !context_lost_cnt_after check. It is not needed. This bug was found when noticing that the smc911x NIC on 3530/Overo was not working, and git bisect tracked it down to this patch. It seems that the spurious context restore was causing the smsc911x to not be properly probed on this platform. Tested-by: Tony Lindgren Acked-by: Tarun Kanti DebBarma Cc: Santosh Shilimkar Signed-off-by: Kevin Hilman --- drivers/gpio/gpio-omap.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/gpio/gpio-omap.c b/drivers/gpio/gpio-omap.c index 9b71f04538aa..b570a6aae6e6 100644 --- a/drivers/gpio/gpio-omap.c +++ b/drivers/gpio/gpio-omap.c @@ -1238,8 +1238,7 @@ static int omap_gpio_runtime_resume(struct device *dev) if (bank->get_context_loss_count) { context_lost_cnt_after = bank->get_context_loss_count(bank->dev); - if (context_lost_cnt_after != bank->context_loss_count || - !context_lost_cnt_after) { + if (context_lost_cnt_after != bank->context_loss_count) { omap_gpio_restore_context(bank); } else { spin_unlock_irqrestore(&bank->lock, flags); -- 2.30.2