[PATCH net 6/9] can: m_can: fix CAN state in system PM
From: Marc Kleine-Budde <mkl@pengutronix.de>
Date: 2025-10-12 14:28:47
Also in:
linux-can
Subsystem:
can network drivers, mcan device driver, the rest · Maintainers:
Marc Kleine-Budde, Vincent Mailhol, Markus Schneider-Pargmann, Linus Torvalds
A suspend/resume cycle on a down interface results in the interface
coming up in Error Active state. A suspend/resume cycle on an Up
interface will always result in Error Active state, regardless of the
actual CAN state.
During suspend, only set running interfaces to CAN_STATE_SLEEPING.
During resume only touch the CAN state of running interfaces. For
wakeup sources, set the CAN state depending on the Protocol Status
Regitser (PSR), for non wakeup source interfaces m_can_start() will do
the same.
Fixes: e0d1f4816f2a ("can: m_can: add Bosch M_CAN controller support")
Reviewed-by: Markus Schneider-Pargmann <msp@baylibre.com>
Link: https://patch.msgid.link/20250929-m_can-fix-state-handling-v4-4-682b49b49d9a@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
---
drivers/net/can/m_can/m_can.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)
diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c
index b6db5b57241c..f2576e577058 100644
--- a/drivers/net/can/m_can/m_can.c
+++ b/drivers/net/can/m_can/m_can.c@@ -2503,12 +2503,11 @@ int m_can_class_suspend(struct device *dev) } m_can_clk_stop(cdev); + cdev->can.state = CAN_STATE_SLEEPING; } pinctrl_pm_select_sleep_state(dev); - cdev->can.state = CAN_STATE_SLEEPING; - return ret; } EXPORT_SYMBOL_GPL(m_can_class_suspend);
@@ -2521,8 +2520,6 @@ int m_can_class_resume(struct device *dev) pinctrl_pm_select_default_state(dev); - cdev->can.state = CAN_STATE_ERROR_ACTIVE; - if (netif_running(ndev)) { ret = m_can_clk_start(cdev); if (ret)
@@ -2540,6 +2537,8 @@ int m_can_class_resume(struct device *dev) if (cdev->ops->init) ret = cdev->ops->init(cdev); + cdev->can.state = m_can_state_get_by_psr(cdev); + m_can_write(cdev, M_CAN_IE, cdev->active_interrupts); } else { ret = m_can_start(ndev);
--
2.51.0