i2c-designware: switch to use runtime PM autosuspend

Using autosuspend helps to reduce the resume latency in situations where
another I2C message is going to be started soon. For example with HID over
I2C touch panels we get several messages in a short period of time while
the touch panel is in use.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

drivers/i2c/busses/i2c-designware-core.c

@@ -600,7 +600,8 @@ i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
 	ret = -EIO;
 
 done:
-	pm_runtime_put(dev->dev);
+	pm_runtime_mark_last_busy(dev->dev);
+	pm_runtime_put_autosuspend(dev->dev);
 	mutex_unlock(&dev->lock);
 
 	return ret;

drivers/i2c/busses/i2c-designware-pcidrv.c

@@ -291,7 +291,8 @@ static int i2c_dw_pci_probe(struct pci_dev *pdev,
 	/* Increase reference counter */
 	get_device(&pdev->dev);
 
-	pm_runtime_put_noidle(&pdev->dev);
+	pm_runtime_set_autosuspend_delay(&pdev->dev, 1000);
+	pm_runtime_use_autosuspend(&pdev->dev);
 	pm_runtime_allow(&pdev->dev);
 
 	return 0;

drivers/i2c/busses/i2c-designware-platdrv.c

@@ -173,9 +173,10 @@ static int dw_i2c_probe(struct platform_device *pdev)
 	/* Increase reference counter */
 	get_device(&pdev->dev);
 
+	pm_runtime_set_autosuspend_delay(&pdev->dev, 1000);
+	pm_runtime_use_autosuspend(&pdev->dev);
 	pm_runtime_set_active(&pdev->dev);
 	pm_runtime_enable(&pdev->dev);
-	pm_runtime_put(&pdev->dev);
 
 	return 0;
 }