linux-kernel - [PATCH v2 03/11] can: m_can: Read register PSR only on error

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Message-Id: <20221206115728.1056014-4-msp@baylibre.com>
Date:   Tue,  6 Dec 2022 12:57:20 +0100
From:   Markus Schneider-Pargmann <msp@...libre.com>
To:     Chandrasekar Ramakrishnan <rcsekar@...sung.com>,
        Marc Kleine-Budde <mkl@...gutronix.de>,
        Wolfgang Grandegger <wg@...ndegger.com>
Cc:     linux-can@...r.kernel.org, netdev@...r.kernel.org,
        linux-kernel@...r.kernel.org,
        Markus Schneider-Pargmann <msp@...libre.com>
Subject: [PATCH v2 03/11] can: m_can: Read register PSR only on error

Only read register PSR if there is an error indicated in irqstatus.

Signed-off-by: Markus Schneider-Pargmann <msp@...libre.com>
---
 drivers/net/can/m_can/m_can.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c
index d30afbb3503b..45c718413abf 100644
--- a/drivers/net/can/m_can/m_can.c
+++ b/drivers/net/can/m_can/m_can.c
@@ -900,7 +900,6 @@ static int m_can_rx_handler(struct net_device *dev, int quota, u32 irqstatus)
 	struct m_can_classdev *cdev = netdev_priv(dev);
 	int rx_work_or_err;
 	int work_done = 0;
-	u32 psr;
 
 	if (!irqstatus)
 		goto end;
@@ -926,13 +925,13 @@ static int m_can_rx_handler(struct net_device *dev, int quota, u32 irqstatus)
 		}
 	}
 
-	psr = m_can_read(cdev, M_CAN_PSR);
-
 	if (irqstatus & IR_ERR_STATE)
-		work_done += m_can_handle_state_errors(dev, psr);
+		work_done += m_can_handle_state_errors(dev,
+						       m_can_read(cdev, M_CAN_PSR));
 
 	if (irqstatus & IR_ERR_BUS_30X)
-		work_done += m_can_handle_bus_errors(dev, irqstatus, psr);
+		work_done += m_can_handle_bus_errors(dev, irqstatus,
+						     m_can_read(cdev, M_CAN_PSR));
 
 	if (irqstatus & IR_RF0N) {
 		rx_work_or_err = m_can_do_rx_poll(dev, (quota - work_done));
-- 
2.38.1