From 11a1ec65834aa7790cf5a6c006d35453fa51d0b0 Mon Sep 17 00:00:00 2001
From: Chris Lew <clew@codeaurora.org>
Date: Wed, 19 Dec 2018 17:07:27 -0800
Subject: [PATCH] soc: qcom: smp2p: Prevent suspend for threaded irq

Add primary IRQ handler that takes a wake source to prevent suspend
while the threaded irq is scheduled and run.

Change-Id: I7ea253320251dc721eea0da5028b69b7ebefdac1
Signed-off-by: Chris Lew <clew@codeaurora.org>
---
 drivers/soc/qcom/smp2p.c | 17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/drivers/soc/qcom/smp2p.c b/drivers/soc/qcom/smp2p.c
index 8f628967f389..7c5a7c6fd782 100644
--- a/drivers/soc/qcom/smp2p.c
+++ b/drivers/soc/qcom/smp2p.c
@@ -18,6 +18,7 @@
 #include <linux/soc/qcom/smem.h>
 #include <linux/soc/qcom/smem_state.h>
 #include <linux/spinlock.h>
+#include <linux/pm_wakeup.h>
 
 #include <linux/ipc_logging.h>
 
@@ -152,6 +153,7 @@ struct qcom_smp2p {
 	struct regmap *ipc_regmap;
 	int ipc_offset;
 	int ipc_bit;
+	struct wakeup_source ws;
 
 	struct mbox_client mbox_client;
 	struct mbox_chan *mbox_chan;
@@ -288,6 +290,14 @@ static void qcom_smp2p_notify_in(struct qcom_smp2p *smp2p)
 	}
 }
 
+static irqreturn_t qcom_smp2p_isr(int irq, void *data)
+{
+	struct qcom_smp2p *smp2p = data;
+
+	__pm_stay_awake(&smp2p->ws);
+	return IRQ_WAKE_THREAD;
+}
+
 /**
  * qcom_smp2p_intr() - interrupt handler for incoming notifications
  * @irq:	unused
@@ -312,7 +322,7 @@ static irqreturn_t qcom_smp2p_intr(int irq, void *data)
 		if (IS_ERR(in)) {
 			dev_err(smp2p->dev,
 				"Unable to acquire remote smp2p item\n");
-			return IRQ_HANDLED;
+			goto out;
 		}
 
 		smp2p->in = in;
@@ -331,6 +341,8 @@ static irqreturn_t qcom_smp2p_intr(int irq, void *data)
 			qcom_smp2p_do_ssr_ack(smp2p);
 	}
 
+out:
+	__pm_relax(&smp2p->ws);
 	return IRQ_HANDLED;
 }
 
@@ -627,12 +639,13 @@ static int qcom_smp2p_probe(struct platform_device *pdev)
 			list_add(&entry->node, &smp2p->outbound);
 		}
 	}
+	wakeup_source_init(&smp2p->ws, "smp2p");
 
 	/* Kick the outgoing edge after allocating entries */
 	qcom_smp2p_kick(smp2p);
 
 	ret = devm_request_threaded_irq(&pdev->dev, smp2p->irq,
-					NULL, qcom_smp2p_intr,
+					qcom_smp2p_isr, qcom_smp2p_intr,
 					IRQF_ONESHOT,
 					"smp2p", (void *)smp2p);
 	if (ret) {