Bluetooth: hci_mrvl: Add serdev support

This adds serdev support to the Marvell hci uart driver. Only basic
serdev support, none of the fancier features like regulator or enable
GPIO support is added for now.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

Documentation/devicetree/bindings/net/marvell-bluetooth.txt

+Marvell Bluetooth Chips
+-----------------------
+
+This documents the binding structure and common properties for serial
+attached Marvell Bluetooth devices. The following chips are included in
+this binding:
+
+* Marvell 88W8897 Bluetooth devices
+
+Required properties:
+ - compatible: should be:
+    "mrvl,88w8897"
+
+Optional properties:
+None so far
+
+Example:
+
+&serial0 {
+	compatible = "ns16550a";
+	...
+	bluetooth {
+		compatible = "mrvl,88w8897";
+	};
+};

drivers/bluetooth/Kconfig

@@ -237,6 +237,7 @@ config BT_HCIUART_AG6XX
 config BT_HCIUART_MRVL
 	bool "Marvell protocol support"
 	depends on BT_HCIUART
+	depends on BT_HCIUART_SERDEV
 	select BT_HCIUART_H4
 	help
 	  Marvell is serial protocol for communication between Bluetooth

drivers/bluetooth/hci_mrvl.c

@@ -13,6 +13,8 @@
 #include <linux/firmware.h>
 #include <linux/module.h>
 #include <linux/tty.h>
+#include <linux/of.h>
+#include <linux/serdev.h>
 
 #include <net/bluetooth/bluetooth.h>
 #include <net/bluetooth/hci_core.h>
@@ -40,6 +42,10 @@ struct mrvl_data {
 	u8 id, rev;
 };
 
+struct mrvl_serdev {
+	struct hci_uart hu;
+};
+
 struct hci_mrvl_pkt {
 	__le16 lhs;
 	__le16 rhs;
@@ -49,6 +55,7 @@ struct hci_mrvl_pkt {
 static int mrvl_open(struct hci_uart *hu)
 {
 	struct mrvl_data *mrvl;
+	int ret;
 
 	BT_DBG("hu %p", hu);
 
@@ -62,7 +69,18 @@ static int mrvl_open(struct hci_uart *hu)
 	set_bit(STATE_CHIP_VER_PENDING, &mrvl->flags);
 
 	hu->priv = mrvl;
+
+	if (hu->serdev) {
+		ret = serdev_device_open(hu->serdev);
+		if (ret)
+			goto err;
+	}
+
 	return 0;
+err:
+	kfree(mrvl);
+
+	return ret;
 }
 
 static int mrvl_close(struct hci_uart *hu)
@@ -71,6 +89,9 @@ static int mrvl_close(struct hci_uart *hu)
 
 	BT_DBG("hu %p", hu);
 
+	if (hu->serdev)
+		serdev_device_close(hu->serdev);
+
 	skb_queue_purge(&mrvl->txq);
 	skb_queue_purge(&mrvl->rawq);
 	kfree_skb(mrvl->rx_skb);
@@ -342,7 +363,11 @@ static int mrvl_setup(struct hci_uart *hu)
 	/* Let the final ack go out before switching the baudrate */
 	hci_uart_wait_until_sent(hu);
 
+	if (hu->serdev)
+		serdev_device_set_baudrate(hu->serdev, 3000000);
+	else
 		hci_uart_set_baudrate(hu, 3000000);
+
 	hci_uart_set_flow_control(hu, false);
 
 	err = mrvl_load_firmware(hu->hdev, "mrvl/uart8897_bt.bin");
@@ -365,12 +390,54 @@ static const struct hci_uart_proto mrvl_proto = {
 	.dequeue	= mrvl_dequeue,
 };
 
+static int mrvl_serdev_probe(struct serdev_device *serdev)
+{
+	struct mrvl_serdev *mrvldev;
+
+	mrvldev = devm_kzalloc(&serdev->dev, sizeof(*mrvldev), GFP_KERNEL);
+	if (!mrvldev)
+		return -ENOMEM;
+
+	mrvldev->hu.serdev = serdev;
+	serdev_device_set_drvdata(serdev, mrvldev);
+
+	return hci_uart_register_device(&mrvldev->hu, &mrvl_proto);
+}
+
+static void mrvl_serdev_remove(struct serdev_device *serdev)
+{
+	struct mrvl_serdev *mrvldev = serdev_device_get_drvdata(serdev);
+
+	hci_uart_unregister_device(&mrvldev->hu);
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id mrvl_bluetooth_of_match[] = {
+	{ .compatible = "mrvl,88w8897" },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, mrvl_bluetooth_of_match);
+#endif
+
+static struct serdev_device_driver mrvl_serdev_driver = {
+	.probe = mrvl_serdev_probe,
+	.remove = mrvl_serdev_remove,
+	.driver = {
+		.name = "hci_uart_mrvl",
+		.of_match_table = of_match_ptr(mrvl_bluetooth_of_match),
+	},
+};
+
 int __init mrvl_init(void)
 {
+	serdev_device_driver_register(&mrvl_serdev_driver);
+
 	return hci_uart_register_proto(&mrvl_proto);
 }
 
 int __exit mrvl_deinit(void)
 {
+	serdev_device_driver_unregister(&mrvl_serdev_driver);
+
 	return hci_uart_unregister_proto(&mrvl_proto);
 }