i2c: tegra: Fix suspending in active runtime PM state

BugLink: https://bugs.launchpad.net/bugs/1862429
commit 9f42de8d4ec2304f10bbc51dc0484f3503d61196 upstream.

I noticed that sometime I2C clock is kept enabled during suspend-resume.
This happens because runtime PM defers dynamic suspension and thus it may
happen that runtime PM is in active state when system enters into suspend.
In particular I2C controller that is used for CPU's DVFS is often kept ON
during suspend because CPU's voltage scaling happens quite often.

Fixes: 8ebf15e9c869 ("i2c: tegra: Move suspend handling to NOIRQ phase")
Cc: <stable@vger.kernel.org> # v5.4+
Tested-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index 7a3291d91a5ee5c8a8f5f4f09520d5f5b65f7c9c..1094d12d2f0b84163b675a68da512d4f40d1d4a6 100644 (file)
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -1711,9 +1711,14 @@ static int tegra_i2c_remove(struct platform_device *pdev)
 static int tegra_i2c_suspend(struct device *dev)
 {
        struct tegra_i2c_dev *i2c_dev = dev_get_drvdata(dev);
+       int err;
 
        i2c_mark_adapter_suspended(&i2c_dev->adapter);
 
+       err = pm_runtime_force_suspend(dev);
+       if (err < 0)
+               return err;
+
        return 0;
 }
 
@@ -1734,6 +1739,10 @@ static int tegra_i2c_resume(struct device *dev)
        if (err)
                return err;
 
+       err = pm_runtime_force_resume(dev);
+       if (err < 0)
+               return err;
+
        i2c_mark_adapter_resumed(&i2c_dev->adapter);
 
        return 0;