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From:   Tedd Ho-Jeong An <hj.tedd.an@gmail.com>
To:     linux-bluetooth@vger.kernel.org
Cc:     Tedd Ho-Jeong An <tedd.an@intel.com>
Subject: [PATCH v5 05/11] Bluetooth: btintel: Fix the first HCI command not work with ROM device
Date:   Thu, 29 Jul 2021 11:35:54 -0700
Message-Id: <20210729183600.281586-6-hj.tedd.an@gmail.com>
In-Reply-To: <20210729183600.281586-1-hj.tedd.an@gmail.com>
References: <20210729183600.281586-1-hj.tedd.an@gmail.com>
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From: Tedd Ho-Jeong An <tedd.an@intel.com>

The some legacy ROM controllers have a bug with the first HCI command
sent to it returning number of completed commands as zero, which would
stall the command processing in the Bluetooth core.

As a workaround, send HCI Rest command first which will reset the
controller to fix the issue.

Signed-off-by: Tedd Ho-Jeong An <tedd.an@intel.com>
---
 drivers/bluetooth/btintel.c | 21 +++++++++++++++++++++
 drivers/bluetooth/btintel.h |  1 +
 drivers/bluetooth/btusb.c   | 16 ++++++++++++++--
 3 files changed, 36 insertions(+), 2 deletions(-)

diff --git a/drivers/bluetooth/btintel.c b/drivers/bluetooth/btintel.c
index bf0ad05b80fe..65ecf2ae9a10 100644
--- a/drivers/bluetooth/btintel.c
+++ b/drivers/bluetooth/btintel.c
@@ -1659,6 +1659,7 @@ static int btintel_legacy_rom_setup(struct hci_dev *hdev,
 
 int btintel_setup_combined(struct hci_dev *hdev)
 {
+	struct btintel_data *intel = hci_get_priv(hdev);
 	const u8 param[1] = { 0xFF };
 	struct intel_version ver;
 	struct intel_version_tlv ver_tlv;
@@ -1667,6 +1668,26 @@ int btintel_setup_combined(struct hci_dev *hdev)
 
 	BT_DBG("%s", hdev->name);
 
+	/* The some controllers have a bug with the first HCI command sent to it
+	 * returning number of completed commands as zero. This would stall the
+	 * command processing in the Bluetooth core.
+	 *
+	 * As a workaround, send HCI Reset command first which will reset the
+	 * number of completed commands and allow normal command processing
+	 * from now on.
+	 */
+	if (test_bit(INTEL_BROKEN_READ_VERSION, &intel->flags)) {
+		skb = __hci_cmd_sync(hdev, HCI_OP_RESET, 0, NULL,
+				     HCI_INIT_TIMEOUT);
+		if (IS_ERR(skb)) {
+			bt_dev_err(hdev,
+				   "sending initial HCI reset failed (%ld)",
+				   PTR_ERR(skb));
+			return PTR_ERR(skb);
+		}
+		kfree_skb(skb);
+	}
+
 	/* Starting from TyP device, the command parameter and response are
 	 * changed even though the OCF for HCI_Intel_Read_Version command
 	 * remains same. The legacy devices can handle even if the
diff --git a/drivers/bluetooth/btintel.h b/drivers/bluetooth/btintel.h
index df7aa30142b4..29b678364a79 100644
--- a/drivers/bluetooth/btintel.h
+++ b/drivers/bluetooth/btintel.h
@@ -143,6 +143,7 @@ struct intel_debug_features {
 #define INTEL_FIRMWARE_LOADED		2
 #define INTEL_FIRMWARE_FAILED		3
 #define INTEL_BOOTING			4
+#define INTEL_BROKEN_READ_VERSION	5
 
 struct btintel_data {
 	unsigned long flags;
diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
index 8c54ab03ee63..a64473c525eb 100644
--- a/drivers/bluetooth/btusb.c
+++ b/drivers/bluetooth/btusb.c
@@ -62,6 +62,7 @@ static struct usb_driver btusb_driver;
 #define BTUSB_QCA_WCN6855	0x1000000
 #define BTUSB_INTEL_NEWGEN	0x2000000
 #define BTUSB_INTEL_COMBINED	0x4000000
+#define BTUSB_INTEL_BROKEN_READ_VERSION 0x8000000
 
 static const struct usb_device_id btusb_table[] = {
 	/* Generic Bluetooth USB device */
@@ -376,11 +377,14 @@ static const struct usb_device_id blacklist_table[] = {
 						     BTUSB_WIDEBAND_SPEECH |
 						     BTUSB_VALID_LE_STATES },
 	{ USB_DEVICE(0x8087, 0x07da), .driver_info = BTUSB_CSR },
-	{ USB_DEVICE(0x8087, 0x07dc), .driver_info = BTUSB_INTEL_COMBINED },
-	{ USB_DEVICE(0x8087, 0x0a2a), .driver_info = BTUSB_INTEL_COMBINED },
+	{ USB_DEVICE(0x8087, 0x07dc), .driver_info = BTUSB_INTEL_COMBINED |
+						     BTUSB_INTEL_BROKEN_READ_VERSION },
+	{ USB_DEVICE(0x8087, 0x0a2a), .driver_info = BTUSB_INTEL_COMBINED |
+						     BTUSB_INTEL_BROKEN_READ_VERSION },
 	{ USB_DEVICE(0x8087, 0x0a2b), .driver_info = BTUSB_INTEL_NEW |
 						     BTUSB_WIDEBAND_SPEECH },
 	{ USB_DEVICE(0x8087, 0x0aa7), .driver_info = BTUSB_INTEL_COMBINED |
+						     BTUSB_INTEL_BROKEN_READ_VERSION |
 						     BTUSB_WIDEBAND_SPEECH },
 	{ USB_DEVICE(0x8087, 0x0aaa), .driver_info = BTUSB_INTEL_NEW |
 						     BTUSB_WIDEBAND_SPEECH |
@@ -4221,6 +4225,11 @@ static int btusb_probe(struct usb_interface *intf,
 
 	priv_size = 0;
 
+	if (id->driver_info & BTUSB_INTEL_COMBINED) {
+		/* Allocate extra space for Intel device */
+		priv_size += sizeof(struct btintel_data);
+	}
+
 	if (id->driver_info & BTUSB_INTEL_NEW) {
 		data->recv_event = btusb_recv_event_intel;
 		data->recv_bulk = btusb_recv_bulk_intel;
@@ -4315,6 +4324,9 @@ static int btusb_probe(struct usb_interface *intf,
 		set_bit(HCI_QUIRK_STRICT_DUPLICATE_FILTER, &hdev->quirks);
 		set_bit(HCI_QUIRK_SIMULTANEOUS_DISCOVERY, &hdev->quirks);
 		set_bit(HCI_QUIRK_NON_PERSISTENT_DIAG, &hdev->quirks);
+
+		if (id->driver_info & BTUSB_INTEL_BROKEN_READ_VERSION)
+			btintel_set_flags(hdev, INTEL_BROKEN_READ_VERSION);
 	}
 
 	if (id->driver_info & BTUSB_INTEL_NEW) {
-- 
2.25.1