From 2b3164186e77ee2807ed75fb4565ff80d2b73300 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 07f61ee76ca60..a87f6ce86cea3 100644 --- a/drivers/net/can/m_can/m_can.c +++ b/drivers/net/can/m_can/m_can.c @@ -1583,7 +1583,6 @@ 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) { @@ -1598,6 +1597,7 @@ 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; -- 2.47.3