i2c: busses: i2c-tegra-hv: Add suspend/resume handler

In suspend handler, it blocks i2c transfer, disables irq and waits for
the work to finish.
In resume handler, it enables irq and unblocks i2c transfer.

STR-390

Change-Id: I8244bb8f00fba4bbb48e4caa43123c964b8e29a3
Signed-off-by: Jinyoung Park <jinyoungp@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/1547599
Reviewed-by: Vishal Annapurve <vannapurve@nvidia.com>
Reviewed-by: Nitin Sehgal <nsehgal@nvidia.com>
Reviewed-by: svc-mobile-coverity <svc-mobile-coverity@nvidia.com>
Reviewed-by: svccoveritychecker <svccoveritychecker@nvidia.com>
GVS: Gerrit_Virtual_Submit
Reviewed-by: Kurt Yi <kyi@nvidia.com>

3 files changed, 48 insertions, 5 deletions

diff --git a/drivers/i2c/busses/i2c-tegra-hv-common.c b/drivers/i2c/busses/i2c-tegra-hv-common.c
index cb89e4063..51338e2a6 100644
--- a/drivers/i2c/busses/i2c-tegra-hv-common.c
+++ b/drivers/i2c/busses/i2c-tegra-hv-common.c
@@ -1,7 +1,7 @@
 /*
  * IVC based Library for I2C services.
  *
- * Copyright (c) 2015-2016, NVIDIA CORPORATION.  All rights reserved.
+ * Copyright (c) 2015-2017, NVIDIA CORPORATION.  All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms and conditions of the GNU General Public License,
@@ -295,12 +295,24 @@ void hv_i2c_comm_chan_free(struct tegra_hv_i2c_comm_chan *comm_chan)
 
 }
 
+void hv_i2c_comm_suspend(struct tegra_hv_i2c_comm_chan *comm_chan)
+{
+        disable_irq(comm_chan->ivck->irq);
+        cancel_work_sync(&comm_chan->hv_comm_dev->work);
+}
+
+void hv_i2c_comm_resume(struct tegra_hv_i2c_comm_chan *comm_chan)
+{
+        enable_irq(comm_chan->ivck->irq);
+        schedule_work(&comm_chan->hv_comm_dev->work);
+}
+
 static irqreturn_t hv_i2c_isr(int irq, void *dev_id)
 {
         struct tegra_hv_i2c_comm_dev *comm_dev =
                 (struct tegra_hv_i2c_comm_dev *)dev_id;
 
-        queue_work(system_wq, &comm_dev->work);
+        schedule_work(&comm_dev->work);
 
         return IRQ_HANDLED;
 }
diff --git a/drivers/i2c/busses/i2c-tegra-hv-common.h b/drivers/i2c/busses/i2c-tegra-hv-common.h
index 9db5565fa..cc64efc85 100644
--- a/drivers/i2c/busses/i2c-tegra-hv-common.h
+++ b/drivers/i2c/busses/i2c-tegra-hv-common.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015-2016, NVIDIA CORPORATION.  All rights reserved.
+ * Copyright (c) 2015-2017, NVIDIA CORPORATION.  All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms and conditions of the GNU General Public License,
@@ -33,6 +33,8 @@ int hv_i2c_get_max_payload(struct tegra_hv_i2c_comm_chan *comm_chan,
 int hv_i2c_comm_chan_cleanup(struct tegra_hv_i2c_comm_chan *comm_chan,
                 phys_addr_t base);
 void hv_i2c_comm_chan_free(struct tegra_hv_i2c_comm_chan *comm_chan);
+void hv_i2c_comm_suspend(struct tegra_hv_i2c_comm_chan *comm_chan);
+void hv_i2c_comm_resume(struct tegra_hv_i2c_comm_chan *comm_chan);
 void *hv_i2c_comm_init(struct device *dev, i2c_isr_handler handler,
                 void *data);
 void tegra_hv_i2c_poll_cleanup(struct tegra_hv_i2c_comm_chan *comm_chan);
diff --git a/drivers/i2c/busses/i2c-tegra-hv.c b/drivers/i2c/busses/i2c-tegra-hv.c
index da0092d03..d7ef1110b 100644
--- a/drivers/i2c/busses/i2c-tegra-hv.c
+++ b/drivers/i2c/busses/i2c-tegra-hv.c
@@ -1,7 +1,7 @@
 /*
  * drivers/i2c/busses/i2c-tegra-hv.c
  *
- * Copyright (C) 2015-2016 NVIDIA Corporation.  All rights reserved.
+ * Copyright (C) 2015-2017 NVIDIA Corporation.  All rights reserved.
  * Author: Arnab Basu <abasu@nvidia.com>
  *
  * This software is licensed under the terms of the GNU General Public
@@ -337,6 +337,33 @@ static void tegra_hv_i2c_shutdown(struct platform_device *pdev)
         i2c_shutdown_adapter(&i2c_dev->adapter);
 }
 
+#ifdef CONFIG_PM_SLEEP
+static int tegra_hv_i2c_suspend(struct device *dev)
+{
+        struct tegra_hv_i2c_dev *i2c_dev = dev_get_drvdata(dev);
+
+        i2c_shutdown_adapter(&i2c_dev->adapter);
+        hv_i2c_comm_suspend(i2c_dev->comm_chan);
+
+        return 0;
+}
+
+static int tegra_hv_i2c_resume(struct device *dev)
+{
+        struct tegra_hv_i2c_dev *i2c_dev = dev_get_drvdata(dev);
+
+        hv_i2c_comm_resume(i2c_dev->comm_chan);
+        i2c_shutdown_clear_adapter(&i2c_dev->adapter);
+
+        return 0;
+}
+
+static const struct dev_pm_ops tegra_hv_i2c_pm_ops = {
+        .suspend_noirq = tegra_hv_i2c_suspend,
+        .resume_noirq = tegra_hv_i2c_resume,
+};
+#endif /* CONFIG_PM_SLEEP */
+
 static struct platform_device_id tegra_hv_i2c_devtype[] = {
         {
                 .name = "tegra12-hv-i2c",
@@ -354,7 +381,9 @@ static struct platform_driver tegra_hv_i2c_driver = {
                 .name  = "tegra-hv-i2c",
                 .owner = THIS_MODULE,
                 .of_match_table = of_match_ptr(tegra_hv_i2c_of_match),
-                .pm    = NULL,
+#ifdef CONFIG_PM_SLEEP
+                .pm    = &tegra_hv_i2c_pm_ops,
+#endif
         },
 };