From 5ae048dd5b0be1c7a2998e90c4b862e5ebcd38ef Mon Sep 17 00:00:00 2001
From: Tony Lindgren <tony@atomide.com>
Date: Tue, 31 May 2016 14:17:06 -0700
Subject: [PATCH] pinctrl: single: Fix missing flush of posted write for a
 wakeirq

commit 0ac3c0a4025f41748a083bdd4970cb3ede802b15 upstream.

With many repeated suspend resume cycles, the pin specific wakeirq
may not always work on omaps. This is because the write to enable the
pin interrupt may not have reached the device over the interconnect
before suspend happens.

Let's fix the issue with a flush of posted write with a readback.

Reported-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
 drivers/pinctrl/pinctrl-single.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/pinctrl/pinctrl-single.c b/drivers/pinctrl/pinctrl-single.c
index 8fda801c5c48..0d19ac11ab9e 100644
--- a/drivers/pinctrl/pinctrl-single.c
+++ b/drivers/pinctrl/pinctrl-single.c
@@ -1632,6 +1632,9 @@ static inline void pcs_irq_set(struct pcs_soc_data *pcs_soc,
 		else
 			mask &= ~soc_mask;
 		pcs->write(mask, pcswi->reg);
+
+		/* flush posted write */
+		mask = pcs->read(pcswi->reg);
 		raw_spin_unlock(&pcs->lock);
 	}