NFC: trf7970a: Add System Suspend/Resume support

Add system suspend/resume support by gracefully
shutting things down when suspending and bringing
the device back to full power when resuming.

Signed-off-by: Mark A. Greer <mgreer@animalcreek.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
diff --git a/drivers/nfc/trf7970a.c b/drivers/nfc/trf7970a.c
index a42675d..3859e02 100644
--- a/drivers/nfc/trf7970a.c
+++ b/drivers/nfc/trf7970a.c
@@ -1594,6 +1594,42 @@
 	return 0;
 }
 
+#ifdef CONFIG_PM_SLEEP
+static int trf7970a_suspend(struct device *dev)
+{
+	struct spi_device *spi = container_of(dev, struct spi_device, dev);
+	struct trf7970a *trf = spi_get_drvdata(spi);
+	int ret = 0;
+
+	dev_dbg(dev, "Suspend\n");
+
+	mutex_lock(&trf->lock);
+
+	trf7970a_shutdown(trf);
+
+	mutex_unlock(&trf->lock);
+
+	return ret;
+}
+
+static int trf7970a_resume(struct device *dev)
+{
+	struct spi_device *spi = container_of(dev, struct spi_device, dev);
+	struct trf7970a *trf = spi_get_drvdata(spi);
+	int ret = 0;
+
+	dev_dbg(dev, "Resume\n");
+
+	mutex_lock(&trf->lock);
+
+	ret = trf7970a_startup(trf);
+
+	mutex_unlock(&trf->lock);
+
+	return ret;
+}
+#endif
+
 #ifdef CONFIG_PM_RUNTIME
 static int trf7970a_pm_runtime_suspend(struct device *dev)
 {
@@ -1629,6 +1665,7 @@
 #endif
 
 static const struct dev_pm_ops trf7970a_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(trf7970a_suspend, trf7970a_resume)
 	SET_RUNTIME_PM_OPS(trf7970a_pm_runtime_suspend,
 			trf7970a_pm_runtime_resume, NULL)
 };