linux-kernel - [PATCH v3 05/16] can: m_can: Keep interrupts enabled during peripheral read

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Date:   Wed, 15 Mar 2023 12:05:35 +0100
From:   Markus Schneider-Pargmann <msp@...libre.com>
To:     Marc Kleine-Budde <mkl@...gutronix.de>,
        Chandrasekar Ramakrishnan <rcsekar@...sung.com>,
        Wolfgang Grandegger <wg@...ndegger.com>
Cc:     Vincent MAILHOL <mailhol.vincent@...adoo.fr>,
        Simon Horman <simon.horman@...igine.com>,
        linux-can@...r.kernel.org, netdev@...r.kernel.org,
        linux-kernel@...r.kernel.org,
        Markus Schneider-Pargmann <msp@...libre.com>
Subject: [PATCH v3 05/16] can: m_can: Keep interrupts enabled during peripheral read

Interrupts currently get disabled if the interrupt status shows new
received data. Non-peripheral chips handle receiving in a worker thread,
but peripheral chips are handling the receive process in the threaded
interrupt routine itself without scheduling it for a different worker.
So there is no need to disable interrupts for peripheral chips.

Signed-off-by: Markus Schneider-Pargmann <msp@...libre.com>
---
 drivers/net/can/m_can/m_can.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c
index e7aceeba3759..a5003435802b 100644
--- a/drivers/net/can/m_can/m_can.c
+++ b/drivers/net/can/m_can/m_can.c
@@ -972,8 +972,8 @@ static int m_can_rx_peripheral(struct net_device *dev, u32 irqstatus)
 	/* Don't re-enable interrupts if the driver had a fatal error
 	 * (e.g., FIFO read failure).
 	 */
-	if (work_done >= 0)
-		m_can_enable_all_interrupts(cdev);
+	if (work_done < 0)
+		m_can_disable_all_interrupts(cdev);
 
 	return work_done;
 }
@@ -1095,11 +1095,12 @@ static irqreturn_t m_can_isr(int irq, void *dev_id)
 	 */
 	if ((ir & IR_RF0N) || (ir & IR_ERR_ALL_30X)) {
 		cdev->irqstatus = ir;
-		m_can_disable_all_interrupts(cdev);
-		if (!cdev->is_peripheral)
+		if (!cdev->is_peripheral) {
+			m_can_disable_all_interrupts(cdev);
 			napi_schedule(&cdev->napi);
-		else if (m_can_rx_peripheral(dev, ir) < 0)
+		} else if (m_can_rx_peripheral(dev, ir) < 0) {
 			goto out_fail;
+		}
 	}
 
 	if (cdev->version == 30) {
-- 
2.39.2