rsi: use separate mutex lock for receive thread

Deadlock issue is observed during our stress tests. The root
cause for the issue is same lock is used between tx and rx threads.

This patch adds a separate mutex lock for rx thread to resolve
the problem.

Signed-off-by: Karun Eagalapati <karun256@gmail.com>
Signed-off-by: Amitkumar Karwar <amit.karwar@redpinesignals.com>
Signed-off-by: Prameela Rani Garnepudi <prameela.j04cs@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

4 files changed, 11 insertions, 8 deletions

diff --git a/drivers/net/wireless/rsi/rsi_91x_main.c b/drivers/net/wireless/rsi/rsi_91x_main.c
index f1cde0c..939f568 100644
--- a/drivers/net/wireless/rsi/rsi_91x_main.c
+++ b/drivers/net/wireless/rsi/rsi_91x_main.c
@@ -221,6 +221,7 @@ struct rsi_hw *rsi_91x_init(void)
 	rsi_init_event(&common->tx_thread.event);
 	mutex_init(&common->mutex);
 	mutex_init(&common->tx_rxlock);
+	mutex_init(&common->rx_lock);
 
 	if (rsi_create_kthread(common,
 			       &common->tx_thread,
diff --git a/drivers/net/wireless/rsi/rsi_91x_sdio_ops.c b/drivers/net/wireless/rsi/rsi_91x_sdio_ops.c
index b6d0e2a..b3f7adc 100644
--- a/drivers/net/wireless/rsi/rsi_91x_sdio_ops.c
+++ b/drivers/net/wireless/rsi/rsi_91x_sdio_ops.c
@@ -230,7 +230,7 @@ void rsi_interrupt_handler(struct rsi_hw *adapter)
 	dev->rx_info.sdio_int_counter++;
 
 	do {
-		mutex_lock(&common->tx_rxlock);
+		mutex_lock(&common->rx_lock);
 		status = rsi_sdio_read_register(common->priv,
 						RSI_FN1_INT_REGISTER,
 						&isr_status);
@@ -238,7 +238,7 @@ void rsi_interrupt_handler(struct rsi_hw *adapter)
 			rsi_dbg(ERR_ZONE,
 				"%s: Failed to Read Intr Status Register\n",
 				__func__);
-			mutex_unlock(&common->tx_rxlock);
+			mutex_unlock(&common->rx_lock);
 			return;
 		}
 		adapter->interrupt_status = isr_status;
@@ -246,7 +246,7 @@ void rsi_interrupt_handler(struct rsi_hw *adapter)
 		if (isr_status == 0) {
 			rsi_set_event(&common->tx_thread.event);
 			dev->rx_info.sdio_intr_status_zero++;
-			mutex_unlock(&common->tx_rxlock);
+			mutex_unlock(&common->rx_lock);
 			return;
 		}
 
@@ -304,7 +304,7 @@ void rsi_interrupt_handler(struct rsi_hw *adapter)
 					rsi_dbg(ERR_ZONE,
 						"%s: Failed to read pkt\n",
 						__func__);
-					mutex_unlock(&common->tx_rxlock);
+					mutex_unlock(&common->rx_lock);
 					return;
 				}
 				break;
@@ -319,7 +319,7 @@ void rsi_interrupt_handler(struct rsi_hw *adapter)
 			}
 			isr_status ^= BIT(isr_type - 1);
 		} while (isr_status);
-		mutex_unlock(&common->tx_rxlock);
+		mutex_unlock(&common->rx_lock);
 	} while (1);
 }
 
diff --git a/drivers/net/wireless/rsi/rsi_91x_usb_ops.c b/drivers/net/wireless/rsi/rsi_91x_usb_ops.c
index d3e0a07..465692b 100644
--- a/drivers/net/wireless/rsi/rsi_91x_usb_ops.c
+++ b/drivers/net/wireless/rsi/rsi_91x_usb_ops.c
@@ -37,14 +37,14 @@ void rsi_usb_rx_thread(struct rsi_common *common)
 		if (atomic_read(&dev->rx_thread.thread_done))
 			goto out;
 
-		mutex_lock(&common->tx_rxlock);
+		mutex_lock(&common->rx_lock);
 		status = rsi_read_pkt(common, 0);
 		if (status) {
 			rsi_dbg(ERR_ZONE, "%s: Failed To read data", __func__);
-			mutex_unlock(&common->tx_rxlock);
+			mutex_unlock(&common->rx_lock);
 			return;
 		}
-		mutex_unlock(&common->tx_rxlock);
+		mutex_unlock(&common->rx_lock);
 		rsi_reset_event(&dev->rx_thread.event);
 		if (adapter->rx_urb_submit(adapter)) {
 			rsi_dbg(ERR_ZONE,
diff --git a/drivers/net/wireless/rsi/rsi_main.h b/drivers/net/wireless/rsi/rsi_main.h
index c2e1c1c..29bccb7 100644
--- a/drivers/net/wireless/rsi/rsi_main.h
+++ b/drivers/net/wireless/rsi/rsi_main.h
@@ -181,6 +181,8 @@ struct rsi_common {
 	struct mutex mutex;
 	/* Mutex used between tx/rx threads */
 	struct mutex tx_rxlock;
+	/* Mutex used for rx thread */
+	struct mutex rx_lock;
 	u8 endpoint;
 
 	/* Channel/band related */