video: tegra: host: Prevent suspend if module is busy

MPE is kept artificially busy if a channel is open. This is done to
prevent power management during an encoding process.

This patch prevents system suspend if any module is busy.

Bug 911477

Change-Id: I943a7e29e473ac33e680281fcdce74618567facb
Signed-off-by: Terje Bergstrom <tbergstrom@nvidia.com>
Reviewed-on: http://git-master/r/69457
Reviewed-by: Rohan Somvanshi <rsomvanshi@nvidia.com>
Tested-by: Rohan Somvanshi <rsomvanshi@nvidia.com>

5 files changed, 25 insertions, 15 deletions

diff --git a/drivers/video/tegra/host/dev.c b/drivers/video/tegra/host/dev.c
index 3af4d3bebfae..75c116b4f081 100644
--- a/drivers/video/tegra/host/dev.c
+++ b/drivers/video/tegra/host/dev.c
@@ -1068,15 +1068,18 @@ static int __exit nvhost_remove(struct platform_device *pdev)
 static int nvhost_suspend(struct platform_device *pdev, pm_message_t state)
 {
 	struct nvhost_master *host = platform_get_drvdata(pdev);
-	int i;
+	int i, ret;
 	dev_info(&pdev->dev, "suspending\n");
 
-	for (i = 0; i < host->nb_channels; i++)
-		nvhost_channel_suspend(&host->channels[i]);
+	for (i = 0; i < host->nb_channels; i++) {
+		ret = nvhost_channel_suspend(&host->channels[i]);
+		if (ret)
+			return ret;
+	}
 
-	nvhost_module_suspend(&host->mod, true);
-	dev_info(&pdev->dev, "suspended\n");
-	return 0;
+	ret = nvhost_module_suspend(&host->mod, true);
+	dev_info(&pdev->dev, "suspend status: %d\n", ret);
+	return ret;
 }
 
 static int nvhost_resume(struct platform_device *pdev)
diff --git a/drivers/video/tegra/host/nvhost_acm.c b/drivers/video/tegra/host/nvhost_acm.c
index 6ea1466f63ce..3d63dd62e2fa 100644
--- a/drivers/video/tegra/host/nvhost_acm.c
+++ b/drivers/video/tegra/host/nvhost_acm.c
@@ -450,7 +450,7 @@ static void debug_not_idle(struct nvhost_master *dev)
 		dev_dbg(&dev->pdev->dev, "tegra_grhost: all locks released\n");
 }
 
-void nvhost_module_suspend(struct nvhost_module *mod, bool system_suspend)
+int nvhost_module_suspend(struct nvhost_module *mod, bool system_suspend)
 {
 	int ret;
 	struct nvhost_master *dev;
@@ -465,8 +465,10 @@ void nvhost_module_suspend(struct nvhost_module *mod, bool system_suspend)
 
 	ret = wait_event_timeout(mod->idle, is_module_idle(mod),
 			ACM_SUSPEND_WAIT_FOR_IDLE_TIMEOUT);
-	if (ret == 0)
-		nvhost_debug_dump(dev);
+	if (ret == 0) {
+		dev_info(&dev->pdev->dev, "%s prevented suspend\n", mod->name);
+		return -EBUSY;
+	}
 
 	if (system_suspend)
 		dev_dbg(&dev->pdev->dev, "tegra_grhost: entered idle\n");
@@ -479,7 +481,7 @@ void nvhost_module_suspend(struct nvhost_module *mod, bool system_suspend)
 	if (mod->desc->suspend)
 		mod->desc->suspend(mod);
 
-	BUG_ON(nvhost_module_powered(mod));
+	return 0;
 }
 
 void nvhost_module_deinit(struct device *dev, struct nvhost_module *mod)
diff --git a/drivers/video/tegra/host/nvhost_acm.h b/drivers/video/tegra/host/nvhost_acm.h
index ce15c9916cd5..1720ff1405fe 100644
--- a/drivers/video/tegra/host/nvhost_acm.h
+++ b/drivers/video/tegra/host/nvhost_acm.h
@@ -85,7 +85,7 @@ int nvhost_module_init(struct nvhost_module *mod, const char *name,
 		struct nvhost_module *parent,
 		struct device *dev);
 void nvhost_module_deinit(struct device *dev, struct nvhost_module *mod);
-void nvhost_module_suspend(struct nvhost_module *mod, bool system_suspend);
+int nvhost_module_suspend(struct nvhost_module *mod, bool system_suspend);
 
 void nvhost_module_reset(struct device *dev, struct nvhost_module *mod);
 void nvhost_module_busy(struct nvhost_module *mod);
diff --git a/drivers/video/tegra/host/nvhost_channel.c b/drivers/video/tegra/host/nvhost_channel.c
index 3a3b9e2022e9..6c4212d776c7 100644
--- a/drivers/video/tegra/host/nvhost_channel.c
+++ b/drivers/video/tegra/host/nvhost_channel.c
@@ -124,14 +124,19 @@ void nvhost_putchannel(struct nvhost_channel *ch, struct nvhost_hwctx *ctx)
 	mutex_unlock(&ch->reflock);
 }
 
-void nvhost_channel_suspend(struct nvhost_channel *ch)
+int nvhost_channel_suspend(struct nvhost_channel *ch)
 {
+	int ret = 0;
+
 	mutex_lock(&ch->reflock);
 	BUG_ON(!channel_cdma_op(ch).stop);
 
 	if (ch->refcount) {
-		nvhost_module_suspend(&ch->mod, false);
-		channel_cdma_op(ch).stop(&ch->cdma);
+		ret = nvhost_module_suspend(&ch->mod, false);
+		if (!ret)
+			channel_cdma_op(ch).stop(&ch->cdma);
 	}
 	mutex_unlock(&ch->reflock);
+
+	return ret;
 }
diff --git a/drivers/video/tegra/host/nvhost_channel.h b/drivers/video/tegra/host/nvhost_channel.h
index 9158317061c1..f48fff615401 100644
--- a/drivers/video/tegra/host/nvhost_channel.h
+++ b/drivers/video/tegra/host/nvhost_channel.h
@@ -108,7 +108,7 @@ int nvhost_channel_submit(
 
 struct nvhost_channel *nvhost_getchannel(struct nvhost_channel *ch);
 void nvhost_putchannel(struct nvhost_channel *ch, struct nvhost_hwctx *ctx);
-void nvhost_channel_suspend(struct nvhost_channel *ch);
+int nvhost_channel_suspend(struct nvhost_channel *ch);
 
 #define channel_cdma_op(ch) (ch->dev->op.cdma)
 #define channel_op(ch) (ch->dev->op.channel)