pinctrl: single: Fix missing flush of posted write for a wakeirq

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.

Cc: stable@vger.kernel.org
Reported-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/drivers/pinctrl/pinctrl-single.c b/drivers/pinctrl/pinctrl-single.c
index cf9bafa10acfb51ad42af96cf6580d6de48c1b1d..bfdf720db270d8b2c47007455406d9887ed028c6 100644 (file)
--- a/drivers/pinctrl/pinctrl-single.c
+++ b/drivers/pinctrl/pinctrl-single.c
@@ -1580,6 +1580,9 @@ 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);
        }