[PATCH 2/2] can: flexcan: add support for ISO CAN-FD

[Michael Walle]

Up until now, the controller used non-ISO CAN-FD mode, although it
supports it. Add support for ISO mode, too. By default the hardware
is in non-ISO mode and an enable bit has to be explicitly set.

Signed-off-by: Michael Walle <mich...@walle.cc>
---
 drivers/net/can/flexcan.c | 19 ++++++++++++++++---
 1 file changed, 16 insertions(+), 3 deletions(-)

diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c
index 183e094f8d66..a92d3cdf4195 100644
--- a/drivers/net/can/flexcan.c
+++ b/drivers/net/can/flexcan.c
@@ -94,6 +94,7 @@
 #define FLEXCAN_CTRL2_MRP              BIT(18)
 #define FLEXCAN_CTRL2_RRS              BIT(17)
 #define FLEXCAN_CTRL2_EACEN            BIT(16)
+#define FLEXCAN_CTRL2_ISOCANFDEN       BIT(12)
 
 /* FLEXCAN memory error control register (MECR) bits */
 #define FLEXCAN_MECR_ECRWRDIS          BIT(31)
@@ -1344,14 +1345,25 @@ static int flexcan_chip_start(struct net_device *dev)
        else
                reg_mcr |= FLEXCAN_MCR_SRX_DIS;
 
-       /* MCR - CAN-FD */
-       if (priv->can.ctrlmode & CAN_CTRLMODE_FD)
+       /* MCR, CTRL2
+        *
+        * CAN-FD mode
+        * ISO CAN-FD mode
+        */
+       reg_ctrl2 = priv->read(&regs->ctrl2);
+       if (priv->can.ctrlmode & CAN_CTRLMODE_FD) {
                reg_mcr |= FLEXCAN_MCR_FDEN;
-       else
+               reg_ctrl2 |= FLEXCAN_CTRL2_ISOCANFDEN;
+       } else {
                reg_mcr &= ~FLEXCAN_MCR_FDEN;
+       }
+
+       if (priv->can.ctrlmode & CAN_CTRLMODE_FD_NON_ISO)
+               reg_ctrl2 &= ~FLEXCAN_CTRL2_ISOCANFDEN;
 
        netdev_dbg(dev, "%s: writing mcr=0x%08x", __func__, reg_mcr);
        priv->write(reg_mcr, &regs->mcr);
+       priv->write(reg_ctrl2, &regs->ctrl2);
 
        /* CTRL
         *
@@ -1952,6 +1964,7 @@ static int flexcan_probe(struct platform_device *pdev)
 
        if (priv->devtype_data->quirks & FLEXCAN_QUIRK_SUPPORT_FD) {
                priv->can.ctrlmode_supported |= CAN_CTRLMODE_FD;
+               priv->can.ctrlmode_supported |= CAN_CTRLMODE_FD_NON_ISO;
                priv->can.bittiming_const = &flexcan_fd_bittiming_const;
                priv->can.data_bittiming_const =
                        &flexcan_fd_data_bittiming_const;
-- 
2.20.1