Commit a9e30a22 authored by Marc Kleine-Budde's avatar Marc Kleine-Budde
Browse files

can: m_can: fix CAN state in system PM 



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: e0d1f481 ("can: m_can: add Bosch M_CAN controller support")
Reviewed-by: default avatarMarkus Schneider-Pargmann <msp@baylibre.com>
Link: https://patch.msgid.link/20250929-m_can-fix-state-handling-v4-4-682b49b49d9a@pengutronix.de


Signed-off-by: default avatarMarc Kleine-Budde <mkl@pengutronix.de>
parent 4942c42f

drivers/net/can/m_can/m_can.c

+3 −4
Original line number Diff line number Diff line
@@ -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);