[PATCH 1/1] Bluetooth: btusb: Support Bluetooth Reset for Mediatek Chip.

[<mark-yw.chen@mediatek.com>]

From: "mark-yw.chen" <mark-yw.chen@mediatek.com>

This change enable Mediatek reset mechanism via USB, it's a specific
reset mechanism with Mediatek chips. To handle error recovery, it use
the cmd_timoeut to reset Mediatek Bluetooth.

Signed-off-by: mark-yw.chen <mark-yw.chen@mediatek.com>
---
 drivers/bluetooth/btusb.c | 138 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 138 insertions(+)

diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
index 0a86713f496b..e8ad8ca4d346 100644
--- a/drivers/bluetooth/btusb.c
+++ b/drivers/bluetooth/btusb.c
@@ -3076,6 +3076,18 @@ static int btusb_shutdown_intel_new(struct hci_dev *hdev)
 	return 0;
 }
 
+/* UHW CR mapping */
+#define BT_MISC			0x70002510
+#define BT_SUBSYS_RST		0x70002610
+#define UDMA_INT_STA_BT		0x74000024
+#define UDMA_INT_STA_BT1	0x74000308
+#define BT_WDT_STATUS		0x740003A0
+#define EP_RST_OPT		0x74011890
+#define EP_RST_IN_OUT_OPT	0x00010001
+#define BT_RST_DONE		0x00000100
+#define BT_RESET_WAIT_MS	100
+#define BT_RESET_NUM_TRIES	10
+
 #define FIRMWARE_MT7663		"mediatek/mt7663pr2h.bin"
 #define FIRMWARE_MT7668		"mediatek/mt7668pr2h.bin"
 
@@ -3650,6 +3662,63 @@ static int btusb_mtk_func_query(struct hci_dev *hdev)
 	return status;
 }
 
+static int btusb_mtk_uhw_reg_write(struct btusb_data *data, u32 reg, u32 val)
+{
+	struct hci_dev *hdev = data->hdev;
+	int pipe, err;
+	void *buf;
+
+	buf = kzalloc(4, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	put_unaligned_le32(val, buf);
+
+	pipe = usb_sndctrlpipe(data->udev, 0);
+	err = usb_control_msg(data->udev, pipe, 0x02,
+			      0x5E,
+			      reg >> 16, reg & 0xffff,
+			      buf, 4, USB_CTRL_SET_TIMEOUT);
+	if (err < 0) {
+		bt_dev_err(hdev, "Failed to write uhw reg(%d)", err);
+		goto err_free_buf;
+	}
+
+err_free_buf:
+	kfree(buf);
+
+	return err;
+}
+
+static int btusb_mtk_uhw_reg_read(struct btusb_data *data, u32 reg, u32 *val)
+{
+	struct hci_dev *hdev = data->hdev;
+	int pipe, err;
+	void *buf;
+
+	buf = kzalloc(4, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	pipe = usb_rcvctrlpipe(data->udev, 0);
+	err = usb_control_msg(data->udev, pipe, 0x01,
+			      0xDE,
+			      reg >> 16, reg & 0xffff,
+			      buf, 4, USB_CTRL_SET_TIMEOUT);
+	if (err < 0) {
+		bt_dev_err(hdev, "Failed to read uhw reg(%d)", err);
+		goto err_free_buf;
+	}
+
+	*val = get_unaligned_le32(buf);
+	bt_dev_info(hdev, "%s: reg=%x, value=0x%08x", __func__, reg, *val);
+
+err_free_buf:
+	kfree(buf);
+
+	return err;
+}
+
 static int btusb_mtk_reg_read(struct btusb_data *data, u32 reg, u32 *val)
 {
 	int pipe, err, size = sizeof(u32);
@@ -3729,6 +3798,9 @@ static int btusb_mtk_setup(struct hci_dev *hdev)
 			 dev_id & 0xffff, (fw_version & 0xff) + 1);
 		err = btusb_mtk_setup_firmware_79xx(hdev, fw_bin_name);
 
+		/* It's Device EndPoint Reset Option Register */
+		btusb_mtk_uhw_reg_write(data, EP_RST_OPT, EP_RST_IN_OUT_OPT);
+
 		/* Enable Bluetooth protocol */
 		param = 1;
 		wmt_params.op = BTMTK_WMT_FUNC_CTRL;
@@ -3852,6 +3924,71 @@ static int btusb_mtk_shutdown(struct hci_dev *hdev)
 	return 0;
 }
 
+static void btusb_mtk_cmd_timeout(struct hci_dev *hdev)
+{
+	struct btusb_data *data = hci_get_drvdata(hdev);
+	u32 val;
+	int err, retry = 0;
+
+	/* It's MediaTek specific bluetooth reset mechanism via USB */
+	if (test_and_set_bit(BTUSB_HW_RESET_ACTIVE, &data->flags)) {
+		bt_dev_err(hdev, "last reset failed? Not resetting again");
+		return;
+	}
+
+	if (enable_autosuspend)
+		usb_disable_autosuspend(data->udev);
+
+	data->sco_num = 0;
+
+	btusb_stop_traffic(data);
+	usb_kill_anchored_urbs(&data->tx_anchor);
+
+	/* It's Device EndPoint Reset Option Register */
+	bt_dev_info(hdev, "Initiating reset mechanism via uhw");
+	btusb_mtk_uhw_reg_write(data, EP_RST_OPT, EP_RST_IN_OUT_OPT);
+	btusb_mtk_uhw_reg_read(data, BT_WDT_STATUS, &val);
+
+	/* MediaTek Bluetooht Reset */
+	btusb_mtk_uhw_reg_write(data, BT_SUBSYS_RST, 1);
+	btusb_mtk_uhw_reg_write(data, UDMA_INT_STA_BT, 0x000000FF);
+	btusb_mtk_uhw_reg_read(data, UDMA_INT_STA_BT, &val);
+	btusb_mtk_uhw_reg_write(data, UDMA_INT_STA_BT1, 0x000000FF);
+	btusb_mtk_uhw_reg_read(data, UDMA_INT_STA_BT1, &val);
+	msleep(20);
+	btusb_mtk_uhw_reg_write(data, BT_SUBSYS_RST, 0);
+	btusb_mtk_uhw_reg_read(data, BT_SUBSYS_RST, &val);
+
+	/* Poll the register until reset is completed */
+	do {
+		btusb_mtk_uhw_reg_read(data, BT_MISC, &val);
+		if ((val & 0x00000100) == BT_RST_DONE) {
+			bt_dev_info(hdev, "Bluetooth Reset Successfully");
+			break;
+		}
+
+		bt_dev_dbg(hdev, "Polling Bluetooth Reset CR");
+		retry++;
+		msleep(BT_RESET_WAIT_MS);
+	} while (retry < BT_RESET_NUM_TRIES);
+
+	btusb_mtk_id_get(data, 0x70010200, &val);
+	bt_dev_info(hdev, "device id (%x)", val);
+
+	/* Re-Setup Mediatek device */
+	err = btusb_mtk_setup(hdev);
+	if (err < 0) {
+		bt_dev_err(hdev, "mtk_setup failed, err = %d", err);
+		return;
+	}
+	hci_reset_dev(hdev);
+
+	if (enable_autosuspend)
+		usb_enable_autosuspend(data->udev);
+
+	clear_bit(BTUSB_HW_RESET_ACTIVE, &data->flags);
+}
+
 static int btusb_recv_acl_mtk(struct hci_dev *hdev, struct sk_buff *skb)
 {
 	struct btusb_data *data = hci_get_drvdata(hdev);
@@ -4689,6 +4826,7 @@ static int btusb_probe(struct usb_interface *intf,
 		hdev->setup = btusb_mtk_setup;
 		hdev->shutdown = btusb_mtk_shutdown;
 		hdev->manufacturer = 70;
+		hdev->cmd_timeout = btusb_mtk_cmd_timeout;
 		data->recv_acl = btusb_recv_acl_mtk;
 		set_bit(HCI_QUIRK_NON_PERSISTENT_SETUP, &hdev->quirks);
 	}
-- 
2.18.0
_______________________________________________
Linux-mediatek mailing list
Linux-mediatek@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-mediatek