From 84c6c670f7da5db329880e70a705a9e7e1a31cf9 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 BugLink: https://bugs.launchpad.net/bugs/2089340 [ 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 Signed-off-by: Portia Stephens Signed-off-by: Stefan Bader --- 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 cf878319b082..a1ea4dee968d 100644 --- a/drivers/net/can/m_can/m_can.c +++ b/drivers/net/can/m_can/m_can.c @@ -1602,7 +1602,6 @@ static int m_can_close(struct net_device *dev) netif_stop_queue(dev); m_can_stop(dev); - m_can_clk_stop(cdev); free_irq(dev->irq, dev); if (cdev->is_peripheral) { @@ -1616,6 +1615,7 @@ static int m_can_close(struct net_device *dev) close_candev(dev); + m_can_clk_stop(cdev); phy_power_off(cdev->transceiver); return 0;