On R-Car Gen3 using PSCI, s2ram powers down the SoC. After resume, the
CAN interface no longer works, until it is brought down and up again.
Fix this by calling rcar_can_start() from the PM resume callback, to
fully initialize the controller instead of just restarting it.
Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
---
Tested on Ebisu-4D with R-Car E3.
FTR, I am working on fixing the same issue in the (separate) R-Car
CAN-FD driver. I already made CAN-FD work after s2ram on Ebisu-4D, but
unfortunately broke it after s2idle on R-Car Gen4 in the process, so that
needs more work...
---
drivers/net/can/rcar/rcar_can.c | 8 +-------
1 file changed, 1 insertion(+), 7 deletions(-)
diff --git a/drivers/net/can/rcar/rcar_can.c b/drivers/net/can/rcar/rcar_can.c
index 64e664f5adcc4ac9..87c134bcd48db559 100644
--- a/drivers/net/can/rcar/rcar_can.c
+++ b/drivers/net/can/rcar/rcar_can.c
@@ -861,7 +861,6 @@ static int rcar_can_resume(struct device *dev)
{
struct net_device *ndev = dev_get_drvdata(dev);
struct rcar_can_priv *priv = netdev_priv(ndev);
- u16 ctlr;
int err;
if (!netif_running(ndev))
@@ -873,12 +872,7 @@ static int rcar_can_resume(struct device *dev)
return err;
}
- ctlr = readw(&priv->regs->ctlr);
- ctlr &= ~RCAR_CAN_CTLR_SLPM;
- writew(ctlr, &priv->regs->ctlr);
- ctlr &= ~RCAR_CAN_CTLR_CANM;
- writew(ctlr, &priv->regs->ctlr);
- priv->can.state = CAN_STATE_ERROR_ACTIVE;
+ rcar_can_start(ndev);
netif_device_attach(ndev);
netif_start_queue(ndev);
--
2.43.0
