[PATCH 2/2] mux: rzv2h-vbenctl: Add suspend and resume support

[Tommaso Merciai]

On deep sleep the USB2PHY block loses power and the VBUS_SEL bit is
cleared. The mux state is read during suspend and stored in the private
memory of the mux_chip. Then the state is restored during resume.

Signed-off-by: Tommaso Merciai <tommaso.merciai.xr@xxxxxxxxxxxxxx>
---
 drivers/mux/rzv2h-vbenctl.c | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/drivers/mux/rzv2h-vbenctl.c b/drivers/mux/rzv2h-vbenctl.c
index 2699458045f3..d088ac3cab2a 100644
--- a/drivers/mux/rzv2h-vbenctl.c
+++ b/drivers/mux/rzv2h-vbenctl.c
@@ -15,6 +15,7 @@
 
 struct mux_rzv2h_vbenctl_priv {
 	struct regmap_field *field;
+	unsigned int hardware_state;
 };
 
 static int mux_rzv2h_vbenctl_set(struct mux_control *mux, int state)
@@ -60,9 +61,29 @@ static int mux_rzv2h_vbenctl_probe(struct auxiliary_device *adev,
 	if (ret < 0)
 		return dev_err_probe(dev, ret, "Failed to register mux chip\n");
 
+	auxiliary_set_drvdata(adev, priv);
+
 	return 0;
 }
 
+static int mux_rzv2h_vbenctl_suspend(struct device *dev)
+{
+	struct mux_rzv2h_vbenctl_priv *priv = dev_get_drvdata(dev);
+
+	return regmap_field_read(priv->field, &priv->hardware_state);
+}
+
+static int mux_rzv2h_vbenctl_resume(struct device *dev)
+{
+	struct mux_rzv2h_vbenctl_priv *priv = dev_get_drvdata(dev);
+
+	return regmap_field_write(priv->field, priv->hardware_state);
+}
+
+static DEFINE_SIMPLE_DEV_PM_OPS(mux_rzv2h_vbenctl_pm_ops,
+				mux_rzv2h_vbenctl_suspend,
+				mux_rzv2h_vbenctl_resume);
+
 static const struct auxiliary_device_id mux_rzv2h_vbenctl_ids[] = {
 	{ .name = "rzv2h_usb2phy_reset.vbenctl" },
 	{ /* sentinel */ }
@@ -73,6 +94,9 @@ static struct auxiliary_driver mux_rzv2h_vbenctl_driver = {
 	.name		= "vbenctl",
 	.probe		= mux_rzv2h_vbenctl_probe,
 	.id_table	= mux_rzv2h_vbenctl_ids,
+	.driver		= {
+		.pm	= pm_sleep_ptr(&mux_rzv2h_vbenctl_pm_ops),
+	},
 };
 module_auxiliary_driver(mux_rzv2h_vbenctl_driver);
 
-- 
2.54.0