Received-SPF: pass (google.com: best guess record for domain of linux-bluetooth-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 320A5C48B2D
From:   Rocky Liao <rjliao@codeaurora.org>
To:     marcel@holtmann.org, johan.hedberg@gmail.com
Cc:     linux-kernel@vger.kernel.org, linux-bluetooth@vger.kernel.org,
        Rocky Liao <rjliao@codeaurora.org>
Subject: [PATCH v1] Bluetooth: hci_qca: Retry btsoc initialize when it fails
Date:   Thu, 19 Dec 2019 14:52:17 +0800
Message-Id: <20191219065217.14122-1-rjliao@codeaurora.org>
Sender: linux-bluetooth-owner@vger.kernel.org
Precedence: bulk

This patch adds the retry of btsoc initialization when it fails. There are
reports that the btsoc initialization may fail on some platforms but the
repro ratio is very low. The failure may be caused by UART, platform HW or
the btsoc itself but it's very difficlut to root cause, given the repro
ratio is very low. Add a retry for the btsoc initialization will resolve
most of the failures and make Bluetooth finally works.

Signed-off-by: Rocky Liao <rjliao@codeaurora.org>
---
 drivers/bluetooth/hci_qca.c | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c
index 1cb706acdef6..af45b31f1b5f 100644
--- a/drivers/bluetooth/hci_qca.c
+++ b/drivers/bluetooth/hci_qca.c
@@ -53,6 +53,9 @@
 /* Controller debug log header */
 #define QCA_DEBUG_HANDLE	0x2EDC
 
+/* max retry count when init fails */
+#define QCA_MAX_INIT_RETRY_COUNT 3
+
 enum qca_flags {
 	QCA_IBS_ENABLED,
 	QCA_DROP_VENDOR_EVENT,
@@ -1259,6 +1262,7 @@ static int qca_setup(struct hci_uart *hu)
 	struct qca_data *qca = hu->priv;
 	struct qca_serdev *qcadev;
 	unsigned int speed, qca_baudrate = QCA_BAUDRATE_115200;
+	unsigned int init_retry_count = 0;
 	enum qca_btsoc_type soc_type = qca_soc_type(hu);
 	const char *firmware_name = qca_get_firmware_name(hu);
 	int ret;
@@ -1276,6 +1280,7 @@ static int qca_setup(struct hci_uart *hu)
 	 */
 	set_bit(HCI_QUIRK_SIMULTANEOUS_DISCOVERY, &hdev->quirks);
 
+retry:
 	if (qca_is_wcn399x(soc_type)) {
 		bt_dev_info(hdev, "setting up wcn3990");
 
@@ -1341,6 +1346,20 @@ static int qca_setup(struct hci_uart *hu)
 		 * patch/nvm-config is found, so run with original fw/config.
 		 */
 		ret = 0;
+	} else {
+		if (init_retry_count < QCA_MAX_INIT_RETRY_COUNT) {
+			qca_power_off(hdev);
+			if (hu->serdev) {
+				serdev_device_close(hu->serdev);
+				ret = serdev_device_open(hu->serdev);
+				if (ret) {
+					bt_dev_err(hu->hdev, "open port fail");
+					return ret;
+				}
+			}
+			init_retry_count++;
+			goto retry;
+		}
 	}
 
 	/* Setup bdaddr */
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project