linux-kernel - [PATCH v2 2/3] PM: domains: Consolidate genpd_restore_noirq() and genpd_resume

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Date:   Tue,  1 Nov 2022 10:47:35 +0800
From:   Shawn Guo <shawn.guo@...aro.org>
To:     "Rafael J . Wysocki" <rafael@...nel.org>
Cc:     Kevin Hilman <khilman@...nel.org>,
        Ulf Hansson <ulf.hansson@...aro.org>,
        Len Brown <len.brown@...el.com>, Pavel Machek <pavel@....cz>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        linux-pm@...r.kernel.org, linux-kernel@...r.kernel.org,
        Shawn Guo <shawn.guo@...aro.org>
Subject: [PATCH v2 2/3] PM: domains: Consolidate genpd_restore_noirq() and genpd_resume_noirq()

Most of the logic between genpd_restore_noirq() and genpd_resume_noirq()
are same except GENPD_STATE_OFF status reset for hibernation restore.
The suspended_count decrement for restore should be the right thing to do
anyway, considering there is an increment in genpd_finish_suspend() for
hibernation.

Consolidate genpd_restore_noirq() and genpd_resume_noirq() into
genpd_finish_resume() and handle GENPD_STATE_OFF status reset for
restore case specially.

Signed-off-by: Shawn Guo <shawn.guo@...aro.org>
---
 drivers/base/power/domain.c | 70 ++++++++++++++++++-------------------
 1 file changed, 35 insertions(+), 35 deletions(-)

diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index 54f6b0dd35fb..b81baeb38d81 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -1247,12 +1247,14 @@ static int genpd_suspend_noirq(struct device *dev)
 }
 
 /**
- * genpd_resume_noirq - Start of resume of device in an I/O PM domain.
+ * genpd_finish_resume - Completion of resume of device in an I/O PM domain.
  * @dev: Device to resume.
+ * @resume_noirq: Generic resume_noirq callback.
  *
  * Restore power to the device's PM domain, if necessary, and start the device.
  */
-static int genpd_resume_noirq(struct device *dev)
+static int genpd_finish_resume(struct device *dev,
+			       int (*resume_noirq)(struct device *dev))
 {
 	struct generic_pm_domain *genpd;
 	int ret;
@@ -1264,9 +1266,25 @@ static int genpd_resume_noirq(struct device *dev)
 		return -EINVAL;
 
 	if (device_wakeup_path(dev) && genpd_is_active_wakeup(genpd))
-		return pm_generic_resume_noirq(dev);
+		return resume_noirq(dev);
 
 	genpd_lock(genpd);
+
+	/*
+	 * Special handling for hibernation restore:
+	 * At this point suspended_count == 0 means we are being run for the
+	 * first time for the given domain in the present cycle.
+	 */
+	if (resume_noirq == pm_generic_restore_noirq &&
+	    genpd->suspended_count++ == 0) {
+		/*
+		 * The boot kernel might put the domain into arbitrary state,
+		 * so make it appear as powered off to genpd_sync_power_on(),
+		 * so that it tries to power it on in case it was really off.
+		 */
+		genpd->status = GENPD_STATE_OFF;
+	}
+
 	genpd_sync_power_on(genpd, true, 0);
 	genpd->suspended_count--;
 	genpd_unlock(genpd);
@@ -1281,6 +1299,19 @@ static int genpd_resume_noirq(struct device *dev)
 	return pm_generic_resume_noirq(dev);
 }
 
+/**
+ * genpd_resume_noirq - Start of resume of device in an I/O PM domain.
+ * @dev: Device to resume.
+ *
+ * Restore power to the device's PM domain, if necessary, and start the device.
+ */
+static int genpd_resume_noirq(struct device *dev)
+{
+	dev_dbg(dev, "%s()\n", __func__);
+
+	return genpd_finish_resume(dev, pm_generic_resume_noirq);
+}
+
 /**
  * genpd_freeze_noirq - Completion of freezing a device in an I/O PM domain.
  * @dev: Device to freeze.
@@ -1366,40 +1397,9 @@ static int genpd_poweroff_noirq(struct device *dev)
  */
 static int genpd_restore_noirq(struct device *dev)
 {
-	struct generic_pm_domain *genpd;
-	int ret = 0;
-
 	dev_dbg(dev, "%s()\n", __func__);
 
-	genpd = dev_to_genpd(dev);
-	if (IS_ERR(genpd))
-		return -EINVAL;
-
-	/*
-	 * At this point suspended_count == 0 means we are being run for the
-	 * first time for the given domain in the present cycle.
-	 */
-	genpd_lock(genpd);
-	if (genpd->suspended_count++ == 0) {
-		/*
-		 * The boot kernel might put the domain into arbitrary state,
-		 * so make it appear as powered off to genpd_sync_power_on(),
-		 * so that it tries to power it on in case it was really off.
-		 */
-		genpd->status = GENPD_STATE_OFF;
-	}
-
-	genpd_sync_power_on(genpd, true, 0);
-	genpd_unlock(genpd);
-
-	if (genpd->dev_ops.stop && genpd->dev_ops.start &&
-	    !pm_runtime_status_suspended(dev)) {
-		ret = genpd_start_dev(genpd, dev);
-		if (ret)
-			return ret;
-	}
-
-	return pm_generic_restore_noirq(dev);
+	return genpd_finish_resume(dev, pm_generic_restore_noirq);
 }
 
 /**
-- 
2.25.1