i2c: sprd: Prevent i2c accesses after suspend is called
authorBaolin Wang <baolin.wang@linaro.org>
Mon, 9 Apr 2018 06:40:54 +0000 (14:40 +0800)
committerWolfram Sang <wsa@the-dreams.de>
Fri, 27 Apr 2018 12:12:17 +0000 (14:12 +0200)
Add one flag to indicate if the i2c controller has been in suspend state,
which can prevent i2c accesses after i2c controller is suspended following
system suspend.

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
drivers/i2c/busses/i2c-sprd.c

index 25fcc3c..2fdad63 100644 (file)
@@ -86,6 +86,7 @@ struct sprd_i2c {
        u32 count;
        int irq;
        int err;
+       bool is_suspended;
 };
 
 static void sprd_i2c_set_count(struct sprd_i2c *i2c_dev, u32 count)
@@ -283,6 +284,9 @@ static int sprd_i2c_master_xfer(struct i2c_adapter *i2c_adap,
        struct sprd_i2c *i2c_dev = i2c_adap->algo_data;
        int im, ret;
 
+       if (i2c_dev->is_suspended)
+               return -EBUSY;
+
        ret = pm_runtime_get_sync(i2c_dev->dev);
        if (ret < 0)
                return ret;
@@ -586,11 +590,23 @@ static int sprd_i2c_remove(struct platform_device *pdev)
 
 static int __maybe_unused sprd_i2c_suspend_noirq(struct device *pdev)
 {
+       struct sprd_i2c *i2c_dev = dev_get_drvdata(pdev);
+
+       i2c_lock_adapter(&i2c_dev->adap);
+       i2c_dev->is_suspended = true;
+       i2c_unlock_adapter(&i2c_dev->adap);
+
        return pm_runtime_force_suspend(pdev);
 }
 
 static int __maybe_unused sprd_i2c_resume_noirq(struct device *pdev)
 {
+       struct sprd_i2c *i2c_dev = dev_get_drvdata(pdev);
+
+       i2c_lock_adapter(&i2c_dev->adap);
+       i2c_dev->is_suspended = false;
+       i2c_unlock_adapter(&i2c_dev->adap);
+
        return pm_runtime_force_resume(pdev);
 }