From 0fd677f8d40f2de55ef5220445807c4b1ba490ef Mon Sep 17 00:00:00 2001 From: Marc Kleine-Budde Date: Mon, 9 Sep 2024 15:07:41 +0200 Subject: [PATCH] can: m_can: m_can_close(): stop clocks after device has been shut down [ Upstream commit 2c09b50efcad985cf920ca88baa9aa52b1999dcc ] After calling m_can_stop() an interrupt may be pending or NAPI might still be executed. This means the driver might still touch registers of the IP core after the clocks have been disabled. This is not good practice and might lead to aborts depending on the SoC integration. To avoid these potential problems, make m_can_close() symmetric to m_can_open(), i.e. stop the clocks at the end, right before shutting down the transceiver. Fixes: e0d1f4816f2a ("can: m_can: add Bosch M_CAN controller support") Link: https://patch.msgid.link/20240910-can-m_can-fix-ifup-v3-2-6c1720ba45ce@pengutronix.de Signed-off-by: Marc Kleine-Budde Signed-off-by: Sasha Levin --- drivers/net/can/m_can/m_can.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c index f314d93ac..6181ac277 100755 --- a/drivers/net/can/m_can/m_can.c +++ b/drivers/net/can/m_can/m_can.c @@ -1427,7 +1427,6 @@ static int m_can_close(struct net_device *dev) napi_disable(&cdev->napi); m_can_stop(dev); - m_can_clk_stop(cdev); free_irq(dev->irq, dev); if (cdev->is_peripheral) { @@ -1439,6 +1438,7 @@ static int m_can_close(struct net_device *dev) close_candev(dev); can_led_event(dev, CAN_LED_EVENT_STOP); + m_can_clk_stop(cdev); phy_power_off(cdev->transceiver); return 0;