[PATCH v2 2/2] can: m_can: add deep Suspend/Resume support

[Quentin Schulz <quentin.schulz@free-electrons.com>]

This adds Power Management deep Suspend/Resume support for Bosch M_CAN
chip.

When the system resumes from deep sleep, the chip needs to be fully
reinitialized (RAM, chip, clocks, irq, candev, ...) to be functional.

Signed-off-by: Quentin Schulz <quentin.schulz@free-electrons.com>
---
 drivers/net/can/m_can/m_can.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c
index 3f0445440146..9e0143b528f1 100644
--- a/drivers/net/can/m_can/m_can.c
+++ b/drivers/net/can/m_can/m_can.c
@@ -1670,12 +1670,10 @@ static __maybe_unused int m_can_suspend(struct device *dev)
 	struct m_can_priv *priv = netdev_priv(ndev);
 
 	if (netif_running(ndev)) {
-		netif_stop_queue(ndev);
 		netif_device_detach(ndev);
+		m_can_close(ndev);
 	}
 
-	/* TODO: enter low power */
-
 	priv->can.state = CAN_STATE_SLEEPING;
 
 	return 0;
@@ -1686,13 +1684,13 @@ static __maybe_unused int m_can_resume(struct device *dev)
 	struct net_device *ndev = dev_get_drvdata(dev);
 	struct m_can_priv *priv = netdev_priv(ndev);
 
-	/* TODO: exit low power */
+	m_can_init_ram(priv);
 
 	priv->can.state = CAN_STATE_ERROR_ACTIVE;
 
 	if (netif_running(ndev)) {
+		m_can_open(ndev);
 		netif_device_attach(ndev);
-		netif_start_queue(ndev);
 	}
 
 	return 0;
-- 
2.11.0