video: tegra: dc: hdmi: defer resume regulator enable

On suspend/resume, defer the blocking regulator enable. Place this slow path
in the dedicated hotplug thread.

bug 1299936
bug 1294872

Change-Id: I61a835c2c37dcae47697482e0023b68684ff19dc
Signed-off-by: Jon Mayo <jmayo@nvidia.com>
Reviewed-on: http://git-master/r/239058
(cherry picked from commit 6e789c76d47a6e144868d1e33f9d79b7fc58405d)
Reviewed-on: http://git-master/r/247365
Tested-by: Jong Kim <jongk@nvidia.com>
Reviewed-by: Automatic_Commit_Validation_User
GVS: Gerrit_Virtual_Submit
Reviewed-by: Matthew Pedro <mapedro@nvidia.com>
Tested-by: Matthew Pedro <mapedro@nvidia.com>

3 files changed, 46 insertions, 28 deletions

diff --git a/drivers/video/tegra/dc/dc.c b/drivers/video/tegra/dc/dc.c
index 7b5d01d034b6..7145fcf2edb1 100644
--- a/drivers/video/tegra/dc/dc.c
+++ b/drivers/video/tegra/dc/dc.c
@@ -2477,8 +2477,7 @@ static int tegra_dc_probe(struct platform_device *ndev)
 	if (dc->out && dc->out->n_modes)
 		tegra_dc_add_modes(dc);
 
-	if (dc->out && dc->out->hotplug_init)
-		dc->out->hotplug_init(&ndev->dev);
+	tegra_dc_hotplug_init(dc);
 
 	if (dc->out_ops && dc->out_ops->detect)
 		dc->out_ops->detect(dc);
@@ -2587,14 +2586,8 @@ static int tegra_dc_suspend(struct platform_device *ndev, pm_message_t state)
 		dc->suspended = true;
 	}
 
-	if (dc->out && dc->out->postsuspend) {
+	if (dc->out && dc->out->postsuspend)
 		dc->out->postsuspend();
-		if (dc->out->type && dc->out->type == TEGRA_DC_OUT_HDMI)
-			/*
-			 * avoid resume event due to voltage falling
-			 */
-			msleep(100);
-	}
 
 	tegra_dc_io_end(dc);
 	mutex_unlock(&dc->lock);
@@ -2622,9 +2615,6 @@ static int tegra_dc_resume(struct platform_device *ndev)
 		dc->enabled = _tegra_dc_enable(dc);
 	}
 
-	if (dc->out && dc->out->hotplug_init)
-		dc->out->hotplug_init(&ndev->dev);
-
 	if (dc->out_ops && dc->out_ops->resume)
 		dc->out_ops->resume(dc);
 	mutex_unlock(&dc->lock);
diff --git a/drivers/video/tegra/dc/dc_priv.h b/drivers/video/tegra/dc/dc_priv.h
index 294ce55590e7..b8d72344515b 100644
--- a/drivers/video/tegra/dc/dc_priv.h
+++ b/drivers/video/tegra/dc/dc_priv.h
@@ -4,7 +4,7 @@
  * Copyright (C) 2010 Google, Inc.
  * Author: Erik Gilling <konkers@android.com>
  *
- * Copyright (c) 2010-2012, NVIDIA CORPORATION, All rights reserved.
+ * Copyright (c) 2010-2013, NVIDIA CORPORATION, All rights reserved.
  *
  * This software is licensed under the terms of the GNU General Public
  * License version 2, as published by the Free Software Foundation, and
@@ -250,6 +250,13 @@ static inline bool tegra_dc_is_powered(struct tegra_dc *dc)
 }
 #endif
 
+
+static inline void tegra_dc_hotplug_init(struct tegra_dc *dc)
+{
+	if (dc->out && dc->out->hotplug_init)
+		dc->out->hotplug_init(&dc->ndev->dev);
+}
+
 extern struct tegra_dc_out_ops tegra_dc_rgb_ops;
 extern struct tegra_dc_out_ops tegra_dc_hdmi_ops;
 extern struct tegra_dc_out_ops tegra_dc_dsi_ops;
diff --git a/drivers/video/tegra/dc/hdmi.c b/drivers/video/tegra/dc/hdmi.c
index 6fdac23cbcef..14eca2f7afcc 100644
--- a/drivers/video/tegra/dc/hdmi.c
+++ b/drivers/video/tegra/dc/hdmi.c
@@ -440,6 +440,29 @@ static inline void tegra_hdmi_clrsetbits(struct tegra_dc_hdmi_data *hdmi,
 	tegra_hdmi_writel(hdmi, val, reg);
 }
 
+static inline void tegra_hdmi_hotplug_signal(struct tegra_dc_hdmi_data *hdmi)
+{
+	queue_delayed_work(system_nrt_wq, &hdmi->work,
+		msecs_to_jiffies(100));
+}
+
+/* disables hotplug IRQ - this must be balanced */
+static inline void tegra_hdmi_hotplug_disable(struct tegra_dc_hdmi_data *hdmi)
+{
+	struct tegra_dc *dc = hdmi->dc;
+
+	disable_irq(gpio_to_irq(dc->out->hotplug_gpio));
+}
+
+/* enables hotplug IRQ - this must be balanced */
+static inline void tegra_hdmi_hotplug_enable(struct tegra_dc_hdmi_data *hdmi)
+{
+	struct tegra_dc *dc = hdmi->dc;
+
+	enable_irq(gpio_to_irq(dc->out->hotplug_gpio));
+}
+
+
 #ifdef CONFIG_DEBUG_FS
 static int dbg_hdmi_show(struct seq_file *m, void *unused)
 {
@@ -666,8 +689,7 @@ static int dbg_hotplug_write(struct file *file, const char __user *addr,
 
 	dc->out->hotplug_state = new_state;
 
-	queue_delayed_work(system_nrt_wq, &hdmi->work,
-		msecs_to_jiffies(100));
+	tegra_hdmi_hotplug_signal(hdmi);
 
 	return len;
 }
@@ -928,10 +950,13 @@ fail:
 
 static void tegra_dc_hdmi_detect_worker(struct work_struct *work)
 {
-	struct tegra_dc_hdmi_data *hdmi =
-		container_of(to_delayed_work(work), struct tegra_dc_hdmi_data, work);
+	struct tegra_dc_hdmi_data *hdmi = container_of(to_delayed_work(work),
+		struct tegra_dc_hdmi_data, work);
 	struct tegra_dc *dc = hdmi->dc;
 
+	/* board files are expected to allow multiple calls to hotplug_init() */
+	tegra_dc_hotplug_init(dc);
+
 #ifdef CONFIG_FRAMEBUFFER_CONSOLE
 	/* Set default videomode on dc before enabling it*/
 	tegra_dc_set_default_videomode(dc);
@@ -956,12 +981,7 @@ static irqreturn_t tegra_dc_hdmi_irq(int irq, void *ptr)
 	spin_lock_irqsave(&hdmi->suspend_lock, flags);
 	if (!hdmi->suspended) {
 		__cancel_delayed_work(&hdmi->work);
-		if (tegra_dc_hdmi_hpd(dc))
-			queue_delayed_work(system_nrt_wq, &hdmi->work,
-					   msecs_to_jiffies(100));
-		else
-			queue_delayed_work(system_nrt_wq, &hdmi->work,
-					   msecs_to_jiffies(30));
+		tegra_hdmi_hotplug_signal(hdmi);
 	}
 	spin_unlock_irqrestore(&hdmi->suspend_lock, flags);
 
@@ -973,6 +993,8 @@ static void tegra_dc_hdmi_suspend(struct tegra_dc *dc)
 	struct tegra_dc_hdmi_data *hdmi = tegra_dc_get_outdata(dc);
 	unsigned long flags;
 
+	/* turn off hotplug detection to avoid resume event when +5V falls */
+	tegra_hdmi_hotplug_disable(hdmi);
 	tegra_nvhdcp_suspend(hdmi->nvhdcp);
 	spin_lock_irqsave(&hdmi->suspend_lock, flags);
 	hdmi->suspended = true;
@@ -982,17 +1004,16 @@ static void tegra_dc_hdmi_suspend(struct tegra_dc *dc)
 static void tegra_dc_hdmi_resume(struct tegra_dc *dc)
 {
 	struct tegra_dc_hdmi_data *hdmi = tegra_dc_get_outdata(dc);
-	bool hpd = tegra_dc_hdmi_hpd(dc);
 	unsigned long flags;
 
 	spin_lock_irqsave(&hdmi->suspend_lock, flags);
 	hdmi->suspended = false;
-
-	queue_delayed_work(system_nrt_wq, &hdmi->work,
-			   msecs_to_jiffies(hpd ? 100 : 30));
-
 	spin_unlock_irqrestore(&hdmi->suspend_lock, flags);
+
 	tegra_nvhdcp_resume(hdmi->nvhdcp);
+	/* restore hotplug detection */
+	tegra_hdmi_hotplug_enable(hdmi);
+	tegra_hdmi_hotplug_signal(hdmi);
 }
 
 #ifdef CONFIG_SWITCH