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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/pinctrl/pinctrl-single.c b/drivers/pinctrl/pinctrl-single.c
index fa2dcbcdb921a76e2407db034260fcd74f66d5d6..c2f616f515c309b85f3ff90a76737024d19fb9f6 100644 (file)
--- a/drivers/pinctrl/pinctrl-single.c
+++ b/drivers/pinctrl/pinctrl-single.c
@@ -1616,6 +1616,9 @@ 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);
        }