6.6-stable review patch. If anyone has any objections, please let me know.
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From: Marc Kleine-Budde mkl@pengutronix.de
[ 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@pengu... Signed-off-by: Marc Kleine-Budde mkl@pengutronix.de Signed-off-by: Sasha Levin sashal@kernel.org --- 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 66221fdf785f8..97666a7595959 100644 --- a/drivers/net/can/m_can/m_can.c +++ b/drivers/net/can/m_can/m_can.c @@ -1600,7 +1600,6 @@ 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) { @@ -1614,6 +1613,7 @@ static int m_can_close(struct net_device *dev)
close_candev(dev);
+ m_can_clk_stop(cdev); phy_power_off(cdev->transceiver);
return 0;