8 files changed, 343 insertions, 382 deletions

diff --git a/drivers/net/can/c_can/Kconfig b/drivers/net/can/c_can/Kconfig
index 61ffc12d8fd8..8ab7103d4f44 100644
--- a/drivers/net/can/c_can/Kconfig
+++ b/drivers/net/can/c_can/Kconfig
@@ -14,6 +14,13 @@ config CAN_C_CAN_PLATFORM
           SPEAr1310 and SPEAr320 evaluation boards & TI (www.ti.com)
           boards like am335x, dm814x, dm813x and dm811x.
 
+config CAN_C_CAN_STRICT_FRAME_ORDERING
+        bool "Force a strict RX CAN frame order (may cause frame loss)"
+        ---help---
+          The RX split buffer prevents packet reordering but can cause packet
+          loss. Only enable this option when you accept to lose CAN frames
+          in favour of getting the received CAN frames in the correct order.
+
 config CAN_C_CAN_PCI
         tristate "Generic PCI Bus based C_CAN/D_CAN driver"
         depends on PCI
diff --git a/drivers/net/can/c_can/c_can.c b/drivers/net/can/c_can/c_can.c
index a5c8dcfa8357..a2ca820b5373 100644
--- a/drivers/net/can/c_can/c_can.c
+++ b/drivers/net/can/c_can/c_can.c
@@ -60,6 +60,8 @@
 #define CONTROL_IE              BIT(1)
 #define CONTROL_INIT            BIT(0)
 
+#define CONTROL_IRQMSK          (CONTROL_EIE | CONTROL_IE | CONTROL_SIE)
+
 /* test register */
 #define TEST_RX                 BIT(7)
 #define TEST_TX1                BIT(6)
@@ -108,11 +110,14 @@
 #define IF_COMM_CONTROL         BIT(4)
 #define IF_COMM_CLR_INT_PND     BIT(3)
 #define IF_COMM_TXRQST          BIT(2)
+#define IF_COMM_CLR_NEWDAT      IF_COMM_TXRQST
 #define IF_COMM_DATAA           BIT(1)
 #define IF_COMM_DATAB           BIT(0)
-#define IF_COMM_ALL             (IF_COMM_MASK | IF_COMM_ARB | \
-                                IF_COMM_CONTROL | IF_COMM_TXRQST | \
-                                IF_COMM_DATAA | IF_COMM_DATAB)
+
+/* TX buffer setup */
+#define IF_COMM_TX              (IF_COMM_ARB | IF_COMM_CONTROL | \
+                                 IF_COMM_TXRQST |                \
+                                 IF_COMM_DATAA | IF_COMM_DATAB)
 
 /* For the low buffers we clear the interrupt bit, but keep newdat */
 #define IF_COMM_RCV_LOW         (IF_COMM_MASK | IF_COMM_ARB | \
@@ -120,12 +125,19 @@
                                  IF_COMM_DATAA | IF_COMM_DATAB)
 
 /* For the high buffers we clear the interrupt bit and newdat */
-#define IF_COMM_RCV_HIGH        (IF_COMM_RCV_LOW | IF_COMM_TXRQST)
+#define IF_COMM_RCV_HIGH        (IF_COMM_RCV_LOW | IF_COMM_CLR_NEWDAT)
+
+
+/* Receive setup of message objects */
+#define IF_COMM_RCV_SETUP       (IF_COMM_MASK | IF_COMM_ARB | IF_COMM_CONTROL)
+
+/* Invalidation of message objects */
+#define IF_COMM_INVAL           (IF_COMM_ARB | IF_COMM_CONTROL)
 
 /* IFx arbitration */
-#define IF_ARB_MSGVAL           BIT(15)
-#define IF_ARB_MSGXTD           BIT(14)
-#define IF_ARB_TRANSMIT         BIT(13)
+#define IF_ARB_MSGVAL           BIT(31)
+#define IF_ARB_MSGXTD           BIT(30)
+#define IF_ARB_TRANSMIT         BIT(29)
 
 /* IFx message control */
 #define IF_MCONT_NEWDAT         BIT(15)
@@ -139,19 +151,17 @@
 #define IF_MCONT_EOB            BIT(7)
 #define IF_MCONT_DLC_MASK       0xf
 
+#define IF_MCONT_RCV            (IF_MCONT_RXIE | IF_MCONT_UMASK)
+#define IF_MCONT_RCV_EOB        (IF_MCONT_RCV | IF_MCONT_EOB)
+
+#define IF_MCONT_TX             (IF_MCONT_TXIE | IF_MCONT_EOB)
+
 /*
  * Use IF1 for RX and IF2 for TX
  */
 #define IF_RX                   0
 #define IF_TX                   1
 
-/* status interrupt */
-#define STATUS_INTERRUPT        0x8000
-
-/* global interrupt masks */
-#define ENABLE_ALL_INTERRUPTS   1
-#define DISABLE_ALL_INTERRUPTS  0
-
 /* minimum timeout for checking BUSY status */
 #define MIN_TIMEOUT_VALUE       6
 
@@ -171,6 +181,7 @@ enum c_can_lec_type {
         LEC_BIT0_ERROR,
         LEC_CRC_ERROR,
         LEC_UNUSED,
+        LEC_MASK = LEC_UNUSED,
 };
 
 /*
@@ -226,143 +237,115 @@ static inline void c_can_reset_ram(const struct c_can_priv *priv, bool enable)
                 priv->raminit(priv, enable);
 }
 
-static inline int get_tx_next_msg_obj(const struct c_can_priv *priv)
+static void c_can_irq_control(struct c_can_priv *priv, bool enable)
 {
-        return (priv->tx_next & C_CAN_NEXT_MSG_OBJ_MASK) +
-                        C_CAN_MSG_OBJ_TX_FIRST;
-}
-
-static inline int get_tx_echo_msg_obj(int txecho)
-{
-        return (txecho & C_CAN_NEXT_MSG_OBJ_MASK) + C_CAN_MSG_OBJ_TX_FIRST;
-}
-
-static u32 c_can_read_reg32(struct c_can_priv *priv, enum reg index)
-{
-        u32 val = priv->read_reg(priv, index);
-        val |= ((u32) priv->read_reg(priv, index + 1)) << 16;
-        return val;
-}
-
-static void c_can_enable_all_interrupts(struct c_can_priv *priv,
-                                                int enable)
-{
-        unsigned int cntrl_save = priv->read_reg(priv,
-                                                C_CAN_CTRL_REG);
+        u32 ctrl = priv->read_reg(priv, C_CAN_CTRL_REG) & ~CONTROL_IRQMSK;
 
         if (enable)
-                cntrl_save |= (CONTROL_SIE | CONTROL_EIE | CONTROL_IE);
-        else
-                cntrl_save &= ~(CONTROL_EIE | CONTROL_IE | CONTROL_SIE);
+                ctrl |= CONTROL_IRQMSK;
 
-        priv->write_reg(priv, C_CAN_CTRL_REG, cntrl_save);
+        priv->write_reg(priv, C_CAN_CTRL_REG, ctrl);
 }
 
-static inline int c_can_msg_obj_is_busy(struct c_can_priv *priv, int iface)
+static void c_can_obj_update(struct net_device *dev, int iface, u32 cmd, u32 obj)
 {
-        int count = MIN_TIMEOUT_VALUE;
+        struct c_can_priv *priv = netdev_priv(dev);
+        int cnt, reg = C_CAN_IFACE(COMREQ_REG, iface);
+
+        priv->write_reg(priv, reg + 1, cmd);
+        priv->write_reg(priv, reg, obj);
 
-        while (count && priv->read_reg(priv,
-                                C_CAN_IFACE(COMREQ_REG, iface)) &
-                                IF_COMR_BUSY) {
-                count--;
+        for (cnt = MIN_TIMEOUT_VALUE; cnt; cnt--) {
+                if (!(priv->read_reg(priv, reg) & IF_COMR_BUSY))
+                        return;
                 udelay(1);
         }
+        netdev_err(dev, "Updating object timed out\n");
 
-        if (!count)
-                return 1;
+}
 
-        return 0;
+static inline void c_can_object_get(struct net_device *dev, int iface,
+                                    u32 obj, u32 cmd)
+{
+        c_can_obj_update(dev, iface, cmd, obj);
 }
 
-static inline void c_can_object_get(struct net_device *dev,
-                                        int iface, int objno, int mask)
+static inline void c_can_object_put(struct net_device *dev, int iface,
+                                    u32 obj, u32 cmd)
 {
-        struct c_can_priv *priv = netdev_priv(dev);
+        c_can_obj_update(dev, iface, cmd | IF_COMM_WR, obj);
+}
 
-        /*
-         * As per specs, after writting the message object number in the
-         * IF command request register the transfer b/w interface
-         * register and message RAM must be complete in 6 CAN-CLK
-         * period.
-         */
-        priv->write_reg(priv, C_CAN_IFACE(COMMSK_REG, iface),
-                        IFX_WRITE_LOW_16BIT(mask));
-        priv->write_reg(priv, C_CAN_IFACE(COMREQ_REG, iface),
-                        IFX_WRITE_LOW_16BIT(objno));
+/*
+ * Note: According to documentation clearing TXIE while MSGVAL is set
+ * is not allowed, but works nicely on C/DCAN. And that lowers the I/O
+ * load significantly.
+ */
+static void c_can_inval_tx_object(struct net_device *dev, int iface, int obj)
+{
+        struct c_can_priv *priv = netdev_priv(dev);
 
-        if (c_can_msg_obj_is_busy(priv, iface))
-                netdev_err(dev, "timed out in object get\n");
+        priv->write_reg(priv, C_CAN_IFACE(MSGCTRL_REG, iface), 0);
+        c_can_object_put(dev, iface, obj, IF_COMM_INVAL);
 }
 
-static inline void c_can_object_put(struct net_device *dev,
-                                        int iface, int objno, int mask)
+static void c_can_inval_msg_object(struct net_device *dev, int iface, int obj)
 {
         struct c_can_priv *priv = netdev_priv(dev);
 
-        /*
-         * As per specs, after writting the message object number in the
-         * IF command request register the transfer b/w interface
-         * register and message RAM must be complete in 6 CAN-CLK
-         * period.
-         */
-        priv->write_reg(priv, C_CAN_IFACE(COMMSK_REG, iface),
-                        (IF_COMM_WR | IFX_WRITE_LOW_16BIT(mask)));
-        priv->write_reg(priv, C_CAN_IFACE(COMREQ_REG, iface),
-                        IFX_WRITE_LOW_16BIT(objno));
-
-        if (c_can_msg_obj_is_busy(priv, iface))
-                netdev_err(dev, "timed out in object put\n");
+        priv->write_reg(priv, C_CAN_IFACE(ARB1_REG, iface), 0);
+        priv->write_reg(priv, C_CAN_IFACE(ARB2_REG, iface), 0);
+        c_can_inval_tx_object(dev, iface, obj);
 }
 
-static void c_can_write_msg_object(struct net_device *dev,
-                        int iface, struct can_frame *frame, int objno)
+static void c_can_setup_tx_object(struct net_device *dev, int iface,
+                                  struct can_frame *frame, int idx)
 {
-        int i;
-        u16 flags = 0;
-        unsigned int id;
         struct c_can_priv *priv = netdev_priv(dev);
-
-        if (!(frame->can_id & CAN_RTR_FLAG))
-                flags |= IF_ARB_TRANSMIT;
+        u16 ctrl = IF_MCONT_TX | frame->can_dlc;
+        bool rtr = frame->can_id & CAN_RTR_FLAG;
+        u32 arb = IF_ARB_MSGVAL;
+        int i;
 
         if (frame->can_id & CAN_EFF_FLAG) {
-                id = frame->can_id & CAN_EFF_MASK;
-                flags |= IF_ARB_MSGXTD;
-        } else
-                id = ((frame->can_id & CAN_SFF_MASK) << 18);
+                arb |= frame->can_id & CAN_EFF_MASK;
+                arb |= IF_ARB_MSGXTD;
+        } else {
+                arb |= (frame->can_id & CAN_SFF_MASK) << 18;
+        }
+
+        if (!rtr)
+                arb |= IF_ARB_TRANSMIT;
 
-        flags |= IF_ARB_MSGVAL;
+        /*
+         * If we change the DIR bit, we need to invalidate the buffer
+         * first, i.e. clear the MSGVAL flag in the arbiter.
+         */
+        if (rtr != (bool)test_bit(idx, &priv->tx_dir)) {
+                u32 obj = idx + C_CAN_MSG_OBJ_TX_FIRST;
+
+                c_can_inval_msg_object(dev, iface, obj);
+                change_bit(idx, &priv->tx_dir);
+        }
+
+        priv->write_reg(priv, C_CAN_IFACE(ARB1_REG, iface), arb);
+        priv->write_reg(priv, C_CAN_IFACE(ARB2_REG, iface), arb >> 16);
 
-        priv->write_reg(priv, C_CAN_IFACE(ARB1_REG, iface),
-                                IFX_WRITE_LOW_16BIT(id));
-        priv->write_reg(priv, C_CAN_IFACE(ARB2_REG, iface), flags |
-                                IFX_WRITE_HIGH_16BIT(id));
+        priv->write_reg(priv, C_CAN_IFACE(MSGCTRL_REG, iface), ctrl);
 
         for (i = 0; i < frame->can_dlc; i += 2) {
                 priv->write_reg(priv, C_CAN_IFACE(DATA1_REG, iface) + i / 2,
                                 frame->data[i] | (frame->data[i + 1] << 8));
         }
-
-        /* enable interrupt for this message object */
-        priv->write_reg(priv, C_CAN_IFACE(MSGCTRL_REG, iface),
-                        IF_MCONT_TXIE | IF_MCONT_TXRQST | IF_MCONT_EOB |
-                        frame->can_dlc);
-        c_can_object_put(dev, iface, objno, IF_COMM_ALL);
 }
 
 static inline void c_can_activate_all_lower_rx_msg_obj(struct net_device *dev,
-                                                int iface,
-                                                int ctrl_mask)
+                                                       int iface)
 {
         int i;
-        struct c_can_priv *priv = netdev_priv(dev);
 
-        for (i = C_CAN_MSG_OBJ_RX_FIRST; i <= C_CAN_MSG_RX_LOW_LAST; i++) {
-                priv->write_reg(priv, C_CAN_IFACE(MSGCTRL_REG, iface),
-                                ctrl_mask & ~IF_MCONT_NEWDAT);
-                c_can_object_put(dev, iface, i, IF_COMM_CONTROL);
-        }
+        for (i = C_CAN_MSG_OBJ_RX_FIRST; i <= C_CAN_MSG_RX_LOW_LAST; i++)
+                c_can_object_get(dev, iface, i, IF_COMM_CLR_NEWDAT);
 }
 
 static int c_can_handle_lost_msg_obj(struct net_device *dev,
@@ -377,6 +360,9 @@ static int c_can_handle_lost_msg_obj(struct net_device *dev,
         priv->write_reg(priv, C_CAN_IFACE(MSGCTRL_REG, iface), ctrl);
         c_can_object_put(dev, iface, objno, IF_COMM_CONTROL);
 
+        stats->rx_errors++;
+        stats->rx_over_errors++;
+
         /* create an error msg */
         skb = alloc_can_err_skb(dev, &frame);
         if (unlikely(!skb))
@@ -384,22 +370,18 @@ static int c_can_handle_lost_msg_obj(struct net_device *dev,
 
         frame->can_id |= CAN_ERR_CRTL;
         frame->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
-        stats->rx_errors++;
-        stats->rx_over_errors++;
 
         netif_receive_skb(skb);
         return 1;
 }
 
-static int c_can_read_msg_object(struct net_device *dev, int iface, int ctrl)
+static int c_can_read_msg_object(struct net_device *dev, int iface, u32 ctrl)
 {
-        u16 flags, data;
-        int i;
-        unsigned int val;
-        struct c_can_priv *priv = netdev_priv(dev);
         struct net_device_stats *stats = &dev->stats;
-        struct sk_buff *skb;
+        struct c_can_priv *priv = netdev_priv(dev);
         struct can_frame *frame;
+        struct sk_buff *skb;
+        u32 arb, data;
 
         skb = alloc_can_skb(dev, &frame);
         if (!skb) {
@@ -409,115 +391,82 @@ static int c_can_read_msg_object(struct net_device *dev, int iface, int ctrl)
 
         frame->can_dlc = get_can_dlc(ctrl & 0x0F);
 
-        flags = priv->read_reg(priv, C_CAN_IFACE(ARB2_REG, iface));
-        val = priv->read_reg(priv, C_CAN_IFACE(ARB1_REG, iface)) |
-                (flags << 16);
+        arb = priv->read_reg(priv, C_CAN_IFACE(ARB1_REG, iface));
+        arb |= priv->read_reg(priv, C_CAN_IFACE(ARB2_REG, iface)) << 16;
 
-        if (flags & IF_ARB_MSGXTD)
-                frame->can_id = (val & CAN_EFF_MASK) | CAN_EFF_FLAG;
+        if (arb & IF_ARB_MSGXTD)
+                frame->can_id = (arb & CAN_EFF_MASK) | CAN_EFF_FLAG;
         else
-                frame->can_id = (val >> 18) & CAN_SFF_MASK;
+                frame->can_id = (arb >> 18) & CAN_SFF_MASK;
 
-        if (flags & IF_ARB_TRANSMIT)
+        if (arb & IF_ARB_TRANSMIT) {
                 frame->can_id |= CAN_RTR_FLAG;
-        else {
-                for (i = 0; i < frame->can_dlc; i += 2) {
-                        data = priv->read_reg(priv,
-                                C_CAN_IFACE(DATA1_REG, iface) + i / 2);
+        } else {
+                int i, dreg = C_CAN_IFACE(DATA1_REG, iface);
+
+                for (i = 0; i < frame->can_dlc; i += 2, dreg ++) {
+                        data = priv->read_reg(priv, dreg);
                         frame->data[i] = data;
                         frame->data[i + 1] = data >> 8;
                 }
         }
 
-        netif_receive_skb(skb);
-
         stats->rx_packets++;
         stats->rx_bytes += frame->can_dlc;
+
+        netif_receive_skb(skb);
         return 0;
 }
 
 static void c_can_setup_receive_object(struct net_device *dev, int iface,
-                                        int objno, unsigned int mask,
-                                        unsigned int id, unsigned int mcont)
+                                       u32 obj, u32 mask, u32 id, u32 mcont)
 {
         struct c_can_priv *priv = netdev_priv(dev);
 
-        priv->write_reg(priv, C_CAN_IFACE(MASK1_REG, iface),
-                        IFX_WRITE_LOW_16BIT(mask));
-
-        /* According to C_CAN documentation, the reserved bit
-         * in IFx_MASK2 register is fixed 1
-         */
-        priv->write_reg(priv, C_CAN_IFACE(MASK2_REG, iface),
-                        IFX_WRITE_HIGH_16BIT(mask) | BIT(13));
+        mask |= BIT(29);
+        priv->write_reg(priv, C_CAN_IFACE(MASK1_REG, iface), mask);
+        priv->write_reg(priv, C_CAN_IFACE(MASK2_REG, iface), mask >> 16);
 
-        priv->write_reg(priv, C_CAN_IFACE(ARB1_REG, iface),
-                        IFX_WRITE_LOW_16BIT(id));
-        priv->write_reg(priv, C_CAN_IFACE(ARB2_REG, iface),
-                        (IF_ARB_MSGVAL | IFX_WRITE_HIGH_16BIT(id)));
+        id |= IF_ARB_MSGVAL;
+        priv->write_reg(priv, C_CAN_IFACE(ARB1_REG, iface), id);
+        priv->write_reg(priv, C_CAN_IFACE(ARB2_REG, iface), id >> 16);
 
         priv->write_reg(priv, C_CAN_IFACE(MSGCTRL_REG, iface), mcont);
-        c_can_object_put(dev, iface, objno, IF_COMM_ALL & ~IF_COMM_TXRQST);
-
-        netdev_dbg(dev, "obj no:%d, msgval:0x%08x\n", objno,
-                        c_can_read_reg32(priv, C_CAN_MSGVAL1_REG));
-}
-
-static void c_can_inval_msg_object(struct net_device *dev, int iface, int objno)
-{
-        struct c_can_priv *priv = netdev_priv(dev);
-
-        priv->write_reg(priv, C_CAN_IFACE(ARB1_REG, iface), 0);
-        priv->write_reg(priv, C_CAN_IFACE(ARB2_REG, iface), 0);
-        priv->write_reg(priv, C_CAN_IFACE(MSGCTRL_REG, iface), 0);
-
-        c_can_object_put(dev, iface, objno, IF_COMM_ARB | IF_COMM_CONTROL);
-
-        netdev_dbg(dev, "obj no:%d, msgval:0x%08x\n", objno,
-                        c_can_read_reg32(priv, C_CAN_MSGVAL1_REG));
-}
-
-static inline int c_can_is_next_tx_obj_busy(struct c_can_priv *priv, int objno)
-{
-        int val = c_can_read_reg32(priv, C_CAN_TXRQST1_REG);
-
-        /*
-         * as transmission request register's bit n-1 corresponds to
-         * message object n, we need to handle the same properly.
-         */
-        if (val & (1 << (objno - 1)))
-                return 1;
-
-        return 0;
+        c_can_object_put(dev, iface, obj, IF_COMM_RCV_SETUP);
 }
 
 static netdev_tx_t c_can_start_xmit(struct sk_buff *skb,
-                                        struct net_device *dev)
+                                    struct net_device *dev)
 {
-        u32 msg_obj_no;
-        struct c_can_priv *priv = netdev_priv(dev);
         struct can_frame *frame = (struct can_frame *)skb->data;
+        struct c_can_priv *priv = netdev_priv(dev);
+        u32 idx, obj;
 
         if (can_dropped_invalid_skb(dev, skb))
                 return NETDEV_TX_OK;
-
-        spin_lock_bh(&priv->xmit_lock);
-        msg_obj_no = get_tx_next_msg_obj(priv);
-
-        /* prepare message object for transmission */
-        c_can_write_msg_object(dev, IF_TX, frame, msg_obj_no);
-        priv->dlc[msg_obj_no - C_CAN_MSG_OBJ_TX_FIRST] = frame->can_dlc;
-        can_put_echo_skb(skb, dev, msg_obj_no - C_CAN_MSG_OBJ_TX_FIRST);
-
         /*
-         * we have to stop the queue in case of a wrap around or
-         * if the next TX message object is still in use
+         * This is not a FIFO. C/D_CAN sends out the buffers
+         * prioritized. The lowest buffer number wins.
          */
-        priv->tx_next++;
-        if (c_can_is_next_tx_obj_busy(priv, get_tx_next_msg_obj(priv)) ||
-                        (priv->tx_next & C_CAN_NEXT_MSG_OBJ_MASK) == 0)
+        idx = fls(atomic_read(&priv->tx_active));
+        obj = idx + C_CAN_MSG_OBJ_TX_FIRST;
+
+        /* If this is the last buffer, stop the xmit queue */
+        if (idx == C_CAN_MSG_OBJ_TX_NUM - 1)
                 netif_stop_queue(dev);
-        spin_unlock_bh(&priv->xmit_lock);
+        /*
+         * Store the message in the interface so we can call
+         * can_put_echo_skb(). We must do this before we enable
+         * transmit as we might race against do_tx().
+         */
+        c_can_setup_tx_object(dev, IF_TX, frame, idx);
+        priv->dlc[idx] = frame->can_dlc;
+        can_put_echo_skb(skb, dev, idx);
+
+        /* Update the active bits */
+        atomic_add((1 << idx), &priv->tx_active);
+        /* Start transmission */
+        c_can_object_put(dev, IF_TX, obj, IF_COMM_TX);
 
         return NETDEV_TX_OK;
 }
@@ -594,11 +543,10 @@ static void c_can_configure_msg_objects(struct net_device *dev)
 
         /* setup receive message objects */
         for (i = C_CAN_MSG_OBJ_RX_FIRST; i < C_CAN_MSG_OBJ_RX_LAST; i++)
-                c_can_setup_receive_object(dev, IF_RX, i, 0, 0,
-                        (IF_MCONT_RXIE | IF_MCONT_UMASK) & ~IF_MCONT_EOB);
+                c_can_setup_receive_object(dev, IF_RX, i, 0, 0, IF_MCONT_RCV);
 
         c_can_setup_receive_object(dev, IF_RX, C_CAN_MSG_OBJ_RX_LAST, 0, 0,
-                        IF_MCONT_EOB | IF_MCONT_RXIE | IF_MCONT_UMASK);
+                                   IF_MCONT_RCV_EOB);
 }
 
 /*
@@ -612,30 +560,22 @@ static int c_can_chip_config(struct net_device *dev)
         struct c_can_priv *priv = netdev_priv(dev);
 
         /* enable automatic retransmission */
-        priv->write_reg(priv, C_CAN_CTRL_REG,
-                        CONTROL_ENABLE_AR);
+        priv->write_reg(priv, C_CAN_CTRL_REG, CONTROL_ENABLE_AR);
 
         if ((priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY) &&
             (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)) {
                 /* loopback + silent mode : useful for hot self-test */
-                priv->write_reg(priv, C_CAN_CTRL_REG, CONTROL_EIE |
-                                CONTROL_SIE | CONTROL_IE | CONTROL_TEST);
-                priv->write_reg(priv, C_CAN_TEST_REG,
-                                TEST_LBACK | TEST_SILENT);
+                priv->write_reg(priv, C_CAN_CTRL_REG, CONTROL_TEST);
+                priv->write_reg(priv, C_CAN_TEST_REG, TEST_LBACK | TEST_SILENT);
         } else if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK) {
                 /* loopback mode : useful for self-test function */
-                priv->write_reg(priv, C_CAN_CTRL_REG, CONTROL_EIE |
-                                CONTROL_SIE | CONTROL_IE | CONTROL_TEST);
+                priv->write_reg(priv, C_CAN_CTRL_REG, CONTROL_TEST);
                 priv->write_reg(priv, C_CAN_TEST_REG, TEST_LBACK);
         } else if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY) {
                 /* silent mode : bus-monitoring mode */
-                priv->write_reg(priv, C_CAN_CTRL_REG, CONTROL_EIE |
-                                CONTROL_SIE | CONTROL_IE | CONTROL_TEST);
+                priv->write_reg(priv, C_CAN_CTRL_REG, CONTROL_TEST);
                 priv->write_reg(priv, C_CAN_TEST_REG, TEST_SILENT);
-        } else
-                /* normal mode*/
-                priv->write_reg(priv, C_CAN_CTRL_REG,
-                                CONTROL_EIE | CONTROL_SIE | CONTROL_IE);
+        }
 
         /* configure message objects */
         c_can_configure_msg_objects(dev);
@@ -643,6 +583,11 @@ static int c_can_chip_config(struct net_device *dev)
         /* set a `lec` value so that we can check for updates later */
         priv->write_reg(priv, C_CAN_STS_REG, LEC_UNUSED);
 
+        /* Clear all internal status */
+        atomic_set(&priv->tx_active, 0);
+        priv->rxmasked = 0;
+        priv->tx_dir = 0;
+
         /* set bittiming params */
         return c_can_set_bittiming(dev);
 }
@@ -657,13 +602,11 @@ static int c_can_start(struct net_device *dev)
         if (err)
                 return err;
 
-        priv->can.state = CAN_STATE_ERROR_ACTIVE;
-
-        /* reset tx helper pointers */
-        priv->tx_next = priv->tx_echo = 0;
+        /* Setup the command for new messages */
+        priv->comm_rcv_high = priv->type != BOSCH_D_CAN ?
+                IF_COMM_RCV_LOW : IF_COMM_RCV_HIGH;
 
-        /* enable status change, error and module interrupts */
-        c_can_enable_all_interrupts(priv, ENABLE_ALL_INTERRUPTS);
+        priv->can.state = CAN_STATE_ERROR_ACTIVE;
 
         return 0;
 }
@@ -672,15 +615,13 @@ static void c_can_stop(struct net_device *dev)
 {
         struct c_can_priv *priv = netdev_priv(dev);
 
-        /* disable all interrupts */
-        c_can_enable_all_interrupts(priv, DISABLE_ALL_INTERRUPTS);
-
-        /* set the state as STOPPED */
+        c_can_irq_control(priv, false);
         priv->can.state = CAN_STATE_STOPPED;
 }
 
 static int c_can_set_mode(struct net_device *dev, enum can_mode mode)
 {
+        struct c_can_priv *priv = netdev_priv(dev);
         int err;
 
         switch (mode) {
@@ -689,6 +630,7 @@ static int c_can_set_mode(struct net_device *dev, enum can_mode mode)
                 if (err)
                         return err;
                 netif_wake_queue(dev);
+                c_can_irq_control(priv, true);
                 break;
         default:
                 return -EOPNOTSUPP;
@@ -724,42 +666,29 @@ static int c_can_get_berr_counter(const struct net_device *dev,
         return err;
 }
 
-/*
- * priv->tx_echo holds the number of the oldest can_frame put for
- * transmission into the hardware, but not yet ACKed by the CAN tx
- * complete IRQ.
- *
- * We iterate from priv->tx_echo to priv->tx_next and check if the
- * packet has been transmitted, echo it back to the CAN framework.
- * If we discover a not yet transmitted packet, stop looking for more.
- */
 static void c_can_do_tx(struct net_device *dev)
 {
         struct c_can_priv *priv = netdev_priv(dev);
         struct net_device_stats *stats = &dev->stats;
-        u32 val, obj, pkts = 0, bytes = 0;
-
-        spin_lock_bh(&priv->xmit_lock);
+        u32 idx, obj, pkts = 0, bytes = 0, pend, clr;
 
-        for (; (priv->tx_next - priv->tx_echo) > 0; priv->tx_echo++) {
-                obj = get_tx_echo_msg_obj(priv->tx_echo);
-                val = c_can_read_reg32(priv, C_CAN_TXRQST1_REG);
+        clr = pend = priv->read_reg(priv, C_CAN_INTPND2_REG);
 
-                if (val & (1 << (obj - 1)))
-                        break;
-
-                can_get_echo_skb(dev, obj - C_CAN_MSG_OBJ_TX_FIRST);
-                bytes += priv->dlc[obj - C_CAN_MSG_OBJ_TX_FIRST];
+        while ((idx = ffs(pend))) {
+                idx--;
+                pend &= ~(1 << idx);
+                obj = idx + C_CAN_MSG_OBJ_TX_FIRST;
+                c_can_inval_tx_object(dev, IF_RX, obj);
+                can_get_echo_skb(dev, idx);
+                bytes += priv->dlc[idx];
                 pkts++;
-                c_can_inval_msg_object(dev, IF_TX, obj);
         }
 
-        /* restart queue if wrap-up or if queue stalled on last pkt */
-        if (((priv->tx_next & C_CAN_NEXT_MSG_OBJ_MASK) != 0) ||
-                        ((priv->tx_echo & C_CAN_NEXT_MSG_OBJ_MASK) == 0))
-                netif_wake_queue(dev);
+        /* Clear the bits in the tx_active mask */
+        atomic_sub(clr, &priv->tx_active);
 
-        spin_unlock_bh(&priv->xmit_lock);
+        if (clr & (1 << (C_CAN_MSG_OBJ_TX_NUM - 1)))
+                netif_wake_queue(dev);
 
         if (pkts) {
                 stats->tx_bytes += bytes;
@@ -800,18 +729,42 @@ static u32 c_can_adjust_pending(u32 pend)
         return pend & ~((1 << lasts) - 1);
 }
 
+static inline void c_can_rx_object_get(struct net_device *dev,
+                                       struct c_can_priv *priv, u32 obj)
+{
+#ifdef CONFIG_CAN_C_CAN_STRICT_FRAME_ORDERING
+        if (obj < C_CAN_MSG_RX_LOW_LAST)
+                c_can_object_get(dev, IF_RX, obj, IF_COMM_RCV_LOW);
+        else
+#endif
+                c_can_object_get(dev, IF_RX, obj, priv->comm_rcv_high);
+}
+
+static inline void c_can_rx_finalize(struct net_device *dev,
+                                     struct c_can_priv *priv, u32 obj)
+{
+#ifdef CONFIG_CAN_C_CAN_STRICT_FRAME_ORDERING
+        if (obj < C_CAN_MSG_RX_LOW_LAST)
+                priv->rxmasked |= BIT(obj - 1);
+        else if (obj == C_CAN_MSG_RX_LOW_LAST) {
+                priv->rxmasked = 0;
+                /* activate all lower message objects */
+                c_can_activate_all_lower_rx_msg_obj(dev, IF_RX);
+        }
+#endif
+        if (priv->type != BOSCH_D_CAN)
+                c_can_object_get(dev, IF_RX, obj, IF_COMM_CLR_NEWDAT);
+}
+
 static int c_can_read_objects(struct net_device *dev, struct c_can_priv *priv,
                               u32 pend, int quota)
 {
-        u32 pkts = 0, ctrl, obj, mcmd;
+        u32 pkts = 0, ctrl, obj;
 
         while ((obj = ffs(pend)) && quota > 0) {
                 pend &= ~BIT(obj - 1);
 
-                mcmd = obj < C_CAN_MSG_RX_LOW_LAST ?
-                        IF_COMM_RCV_LOW : IF_COMM_RCV_HIGH;
-
-                c_can_object_get(dev, IF_RX, obj, mcmd);
+                c_can_rx_object_get(dev, priv, obj);
                 ctrl = priv->read_reg(priv, C_CAN_IFACE(MSGCTRL_REG, IF_RX));
 
                 if (ctrl & IF_MCONT_MSGLST) {
@@ -833,9 +786,7 @@ static int c_can_read_objects(struct net_device *dev, struct c_can_priv *priv,
                 /* read the data from the message object */
                 c_can_read_msg_object(dev, IF_RX, ctrl);
 
-                if (obj == C_CAN_MSG_RX_LOW_LAST)
-                        /* activate all lower message objects */
-                        c_can_activate_all_lower_rx_msg_obj(dev, IF_RX, ctrl);
+                c_can_rx_finalize(dev, priv, obj);
 
                 pkts++;
                 quota--;
@@ -844,6 +795,16 @@ static int c_can_read_objects(struct net_device *dev, struct c_can_priv *priv,
         return pkts;
 }
 
+static inline u32 c_can_get_pending(struct c_can_priv *priv)
+{
+        u32 pend = priv->read_reg(priv, C_CAN_NEWDAT1_REG);
+
+#ifdef CONFIG_CAN_C_CAN_STRICT_FRAME_ORDERING
+        pend &= ~priv->rxmasked;
+#endif
+        return pend;
+}
+
 /*
  * theory of operation:
  *
@@ -853,6 +814,8 @@ static int c_can_read_objects(struct net_device *dev, struct c_can_priv *priv,
  * has arrived. To work-around this issue, we keep two groups of message
  * objects whose partitioning is defined by C_CAN_MSG_OBJ_RX_SPLIT.
  *
+ * If CONFIG_CAN_C_CAN_STRICT_FRAME_ORDERING = y
+ *
  * To ensure in-order frame reception we use the following
  * approach while re-activating a message object to receive further
  * frames:
@@ -865,6 +828,14 @@ static int c_can_read_objects(struct net_device *dev, struct c_can_priv *priv,
  * - if the current message object number is greater than
  *   C_CAN_MSG_RX_LOW_LAST then clear the NEWDAT bit of
  *   only this message object.
+ *
+ * This can cause packet loss!
+ *
+ * If CONFIG_CAN_C_CAN_STRICT_FRAME_ORDERING = n
+ *
+ * We clear the newdat bit right away.
+ *
+ * This can result in packet reordering when the readout is slow.
  */
 static int c_can_do_rx_poll(struct net_device *dev, int quota)
 {
@@ -880,7 +851,7 @@ static int c_can_do_rx_poll(struct net_device *dev, int quota)
 
         while (quota > 0) {
                 if (!pend) {
-                        pend = priv->read_reg(priv, C_CAN_INTPND1_REG);
+                        pend = c_can_get_pending(priv);
                         if (!pend)
                                 break;
                         /*
@@ -905,12 +876,6 @@ static int c_can_do_rx_poll(struct net_device *dev, int quota)
         return pkts;
 }
 
-static inline int c_can_has_and_handle_berr(struct c_can_priv *priv)
-{
-        return (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING) &&
-                (priv->current_status & LEC_UNUSED);
-}
-
 static int c_can_handle_state_change(struct net_device *dev,
                                 enum c_can_bus_error_types error_type)
 {
@@ -922,6 +887,26 @@ static int c_can_handle_state_change(struct net_device *dev,
         struct sk_buff *skb;
         struct can_berr_counter bec;
 
+        switch (error_type) {
+        case C_CAN_ERROR_WARNING:
+                /* error warning state */
+                priv->can.can_stats.error_warning++;
+                priv->can.state = CAN_STATE_ERROR_WARNING;
+                break;
+        case C_CAN_ERROR_PASSIVE:
+                /* error passive state */
+                priv->can.can_stats.error_passive++;
+                priv->can.state = CAN_STATE_ERROR_PASSIVE;
+                break;
+        case C_CAN_BUS_OFF:
+                /* bus-off state */
+                priv->can.state = CAN_STATE_BUS_OFF;
+                can_bus_off(dev);
+                break;
+        default:
+                break;
+        }
+
         /* propagate the error condition to the CAN stack */
         skb = alloc_can_err_skb(dev, &cf);
         if (unlikely(!skb))
@@ -935,8 +920,6 @@ static int c_can_handle_state_change(struct net_device *dev,
         switch (error_type) {
         case C_CAN_ERROR_WARNING:
                 /* error warning state */
-                priv->can.can_stats.error_warning++;
-                priv->can.state = CAN_STATE_ERROR_WARNING;
                 cf->can_id |= CAN_ERR_CRTL;
                 cf->data[1] = (bec.txerr > bec.rxerr) ?
                         CAN_ERR_CRTL_TX_WARNING :
@@ -947,8 +930,6 @@ static int c_can_handle_state_change(struct net_device *dev,
                 break;
         case C_CAN_ERROR_PASSIVE:
                 /* error passive state */
-                priv->can.can_stats.error_passive++;
-                priv->can.state = CAN_STATE_ERROR_PASSIVE;
                 cf->can_id |= CAN_ERR_CRTL;
                 if (rx_err_passive)
                         cf->data[1] |= CAN_ERR_CRTL_RX_PASSIVE;
@@ -960,22 +941,16 @@ static int c_can_handle_state_change(struct net_device *dev,
                 break;
         case C_CAN_BUS_OFF:
                 /* bus-off state */
-                priv->can.state = CAN_STATE_BUS_OFF;
                 cf->can_id |= CAN_ERR_BUSOFF;
-                /*
-                 * disable all interrupts in bus-off mode to ensure that
-                 * the CPU is not hogged down
-                 */
-                c_can_enable_all_interrupts(priv, DISABLE_ALL_INTERRUPTS);
                 can_bus_off(dev);
                 break;
         default:
                 break;
         }
 
-        netif_receive_skb(skb);
         stats->rx_packets++;
         stats->rx_bytes += cf->can_dlc;
+        netif_receive_skb(skb);
 
         return 1;
 }
@@ -996,6 +971,13 @@ static int c_can_handle_bus_err(struct net_device *dev,
         if (lec_type == LEC_UNUSED || lec_type == LEC_NO_ERROR)
                 return 0;
 
+        if (!(priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING))
+                return 0;
+
+        /* common for all type of bus errors */
+        priv->can.can_stats.bus_error++;
+        stats->rx_errors++;
+
         /* propagate the error condition to the CAN stack */
         skb = alloc_can_err_skb(dev, &cf);
         if (unlikely(!skb))
@@ -1005,10 +987,6 @@ static int c_can_handle_bus_err(struct net_device *dev,
          * check for 'last error code' which tells us the
          * type of the last error to occur on the CAN bus
          */
-
-        /* common for all type of bus errors */
-        priv->can.can_stats.bus_error++;
-        stats->rx_errors++;
         cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
         cf->data[2] |= CAN_ERR_PROT_UNSPEC;
 
@@ -1043,95 +1021,64 @@ static int c_can_handle_bus_err(struct net_device *dev,
                 break;
         }
 
-        /* set a `lec` value so that we can check for updates later */
-        priv->write_reg(priv, C_CAN_STS_REG, LEC_UNUSED);
-
-        netif_receive_skb(skb);
         stats->rx_packets++;
         stats->rx_bytes += cf->can_dlc;
-
+        netif_receive_skb(skb);
         return 1;
 }
 
 static int c_can_poll(struct napi_struct *napi, int quota)
 {
-        u16 irqstatus;
-        int lec_type = 0;
-        int work_done = 0;
         struct net_device *dev = napi->dev;
         struct c_can_priv *priv = netdev_priv(dev);
+        u16 curr, last = priv->last_status;
+        int work_done = 0;
 
-        irqstatus = priv->irqstatus;
-        if (!irqstatus)
-                goto end;
+        priv->last_status = curr = priv->read_reg(priv, C_CAN_STS_REG);
+        /* Ack status on C_CAN. D_CAN is self clearing */
+        if (priv->type != BOSCH_D_CAN)
+                priv->write_reg(priv, C_CAN_STS_REG, LEC_UNUSED);
 
-        /* status events have the highest priority */
-        if (irqstatus == STATUS_INTERRUPT) {
-                priv->current_status = priv->read_reg(priv,
-                                        C_CAN_STS_REG);
-
-                /* handle Tx/Rx events */
-                if (priv->current_status & STATUS_TXOK)
-                        priv->write_reg(priv, C_CAN_STS_REG,
-                                        priv->current_status & ~STATUS_TXOK);
-
-                if (priv->current_status & STATUS_RXOK)
-                        priv->write_reg(priv, C_CAN_STS_REG,
-                                        priv->current_status & ~STATUS_RXOK);
-
-                /* handle state changes */
-                if ((priv->current_status & STATUS_EWARN) &&
-                                (!(priv->last_status & STATUS_EWARN))) {
-                        netdev_dbg(dev, "entered error warning state\n");
-                        work_done += c_can_handle_state_change(dev,
-                                                C_CAN_ERROR_WARNING);
-                }
-                if ((priv->current_status & STATUS_EPASS) &&
-                                (!(priv->last_status & STATUS_EPASS))) {
-                        netdev_dbg(dev, "entered error passive state\n");
-                        work_done += c_can_handle_state_change(dev,
-                                                C_CAN_ERROR_PASSIVE);
-                }
-                if ((priv->current_status & STATUS_BOFF) &&
-                                (!(priv->last_status & STATUS_BOFF))) {
-                        netdev_dbg(dev, "entered bus off state\n");
-                        work_done += c_can_handle_state_change(dev,
-                                                C_CAN_BUS_OFF);
-                }
+        /* handle state changes */
+        if ((curr & STATUS_EWARN) && (!(last & STATUS_EWARN))) {
+                netdev_dbg(dev, "entered error warning state\n");
+                work_done += c_can_handle_state_change(dev, C_CAN_ERROR_WARNING);
+        }
 
-                /* handle bus recovery events */
-                if ((!(priv->current_status & STATUS_BOFF)) &&
-                                (priv->last_status & STATUS_BOFF)) {
-                        netdev_dbg(dev, "left bus off state\n");
-                        priv->can.state = CAN_STATE_ERROR_ACTIVE;
-                }
-                if ((!(priv->current_status & STATUS_EPASS)) &&
-                                (priv->last_status & STATUS_EPASS)) {
-                        netdev_dbg(dev, "left error passive state\n");
-                        priv->can.state = CAN_STATE_ERROR_ACTIVE;
-                }
+        if ((curr & STATUS_EPASS) && (!(last & STATUS_EPASS))) {
+                netdev_dbg(dev, "entered error passive state\n");
+                work_done += c_can_handle_state_change(dev, C_CAN_ERROR_PASSIVE);
+        }
+
+        if ((curr & STATUS_BOFF) && (!(last & STATUS_BOFF))) {
+                netdev_dbg(dev, "entered bus off state\n");
+                work_done += c_can_handle_state_change(dev, C_CAN_BUS_OFF);
+                goto end;
+        }
 
-                priv->last_status = priv->current_status;
-
-                /* handle lec errors on the bus */
-                lec_type = c_can_has_and_handle_berr(priv);
-                if (lec_type)
-                        work_done += c_can_handle_bus_err(dev, lec_type);
-        } else if ((irqstatus >= C_CAN_MSG_OBJ_RX_FIRST) &&
-                        (irqstatus <= C_CAN_MSG_OBJ_RX_LAST)) {
-                /* handle events corresponding to receive message objects */
-                work_done += c_can_do_rx_poll(dev, (quota - work_done));
-        } else if ((irqstatus >= C_CAN_MSG_OBJ_TX_FIRST) &&
-                        (irqstatus <= C_CAN_MSG_OBJ_TX_LAST)) {
-                /* handle events corresponding to transmit message objects */
-                c_can_do_tx(dev);
+        /* handle bus recovery events */
+        if ((!(curr & STATUS_BOFF)) && (last & STATUS_BOFF)) {
+                netdev_dbg(dev, "left bus off state\n");
+                priv->can.state = CAN_STATE_ERROR_ACTIVE;
+        }
+        if ((!(curr & STATUS_EPASS)) && (last & STATUS_EPASS)) {
+                netdev_dbg(dev, "left error passive state\n");
+                priv->can.state = CAN_STATE_ERROR_ACTIVE;
         }
 
+        /* handle lec errors on the bus */
+        work_done += c_can_handle_bus_err(dev, curr & LEC_MASK);
+
+        /* Handle Tx/Rx events. We do this unconditionally */
+        work_done += c_can_do_rx_poll(dev, (quota - work_done));
+        c_can_do_tx(dev);
+
 end:
         if (work_done < quota) {
                 napi_complete(napi);
-                /* enable all IRQs */
-                c_can_enable_all_interrupts(priv, ENABLE_ALL_INTERRUPTS);
+                /* enable all IRQs if we are not in bus off state */
+                if (priv->can.state != CAN_STATE_BUS_OFF)
+                        c_can_irq_control(priv, true);
         }
 
         return work_done;
@@ -1142,12 +1089,11 @@ static irqreturn_t c_can_isr(int irq, void *dev_id)
         struct net_device *dev = (struct net_device *)dev_id;
         struct c_can_priv *priv = netdev_priv(dev);
 
-        priv->irqstatus = priv->read_reg(priv, C_CAN_INT_REG);
-        if (!priv->irqstatus)
+        if (!priv->read_reg(priv, C_CAN_INT_REG))
                 return IRQ_NONE;
 
         /* disable all interrupts and schedule the NAPI */
-        c_can_enable_all_interrupts(priv, DISABLE_ALL_INTERRUPTS);
+        c_can_irq_control(priv, false);
         napi_schedule(&priv->napi);
 
         return IRQ_HANDLED;
@@ -1184,6 +1130,8 @@ static int c_can_open(struct net_device *dev)
         can_led_event(dev, CAN_LED_EVENT_OPEN);
 
         napi_enable(&priv->napi);
+        /* enable status change, error and module interrupts */
+        c_can_irq_control(priv, true);
         netif_start_queue(dev);
 
         return 0;
@@ -1226,7 +1174,6 @@ struct net_device *alloc_c_can_dev(void)
                 return NULL;
 
         priv = netdev_priv(dev);
-        spin_lock_init(&priv->xmit_lock);
         netif_napi_add(dev, &priv->napi, c_can_poll, C_CAN_NAPI_WEIGHT);
 
         priv->dev = dev;
@@ -1281,6 +1228,7 @@ int c_can_power_up(struct net_device *dev)
         u32 val;
         unsigned long time_out;
         struct c_can_priv *priv = netdev_priv(dev);
+        int ret;
 
         if (!(dev->flags & IFF_UP))
                 return 0;
@@ -1307,7 +1255,11 @@ int c_can_power_up(struct net_device *dev)
         if (time_after(jiffies, time_out))
                 return -ETIMEDOUT;
 
-        return c_can_start(dev);
+        ret = c_can_start(dev);
+        if (!ret)
+                c_can_irq_control(priv, true);
+
+        return ret;
 }
 EXPORT_SYMBOL_GPL(c_can_power_up);
 #endif
diff --git a/drivers/net/can/c_can/c_can.h b/drivers/net/can/c_can/c_can.h
index faa8404162b3..c56f1b1c11ca 100644
--- a/drivers/net/can/c_can/c_can.h
+++ b/drivers/net/can/c_can/c_can.h
@@ -22,14 +22,6 @@
 #ifndef C_CAN_H
 #define C_CAN_H
 
-/*
- * IFx register masks:
- * allow easy operation on 16-bit registers when the
- * argument is 32-bit instead
- */
-#define IFX_WRITE_LOW_16BIT(x)  ((x) & 0xFFFF)
-#define IFX_WRITE_HIGH_16BIT(x) (((x) & 0xFFFF0000) >> 16)
-
 /* message object split */
 #define C_CAN_NO_OF_OBJECTS     32
 #define C_CAN_MSG_OBJ_RX_NUM    16
@@ -45,8 +37,6 @@
 
 #define C_CAN_MSG_OBJ_RX_SPLIT  9
 #define C_CAN_MSG_RX_LOW_LAST   (C_CAN_MSG_OBJ_RX_SPLIT - 1)
-
-#define C_CAN_NEXT_MSG_OBJ_MASK (C_CAN_MSG_OBJ_TX_NUM - 1)
 #define RECEIVE_OBJECT_BITS     0x0000ffff
 
 enum reg {
@@ -183,23 +173,20 @@ struct c_can_priv {
         struct napi_struct napi;
         struct net_device *dev;
         struct device *device;
-        spinlock_t xmit_lock;
-        int tx_object;
-        int current_status;
+        atomic_t tx_active;
+        unsigned long tx_dir;
         int last_status;
         u16 (*read_reg) (struct c_can_priv *priv, enum reg index);
         void (*write_reg) (struct c_can_priv *priv, enum reg index, u16 val);
         void __iomem *base;
         const u16 *regs;
-        unsigned long irq_flags; /* for request_irq() */
-        unsigned int tx_next;
-        unsigned int tx_echo;
         void *priv;             /* for board-specific data */
-        u16 irqstatus;
         enum c_can_dev_id type;
         u32 __iomem *raminit_ctrlreg;
-        unsigned int instance;
+        int instance;
         void (*raminit) (const struct c_can_priv *priv, bool enable);
+        u32 comm_rcv_high;
+        u32 rxmasked;
         u32 dlc[C_CAN_MSG_OBJ_TX_NUM];
 };
 
diff --git a/drivers/net/can/c_can/c_can_pci.c b/drivers/net/can/c_can/c_can_pci.c
index bce0be54c2f5..fe5f6303b584 100644
--- a/drivers/net/can/c_can/c_can_pci.c
+++ b/drivers/net/can/c_can/c_can_pci.c
@@ -84,8 +84,11 @@ static int c_can_pci_probe(struct pci_dev *pdev,
                 goto out_disable_device;
         }
 
-        pci_set_master(pdev);
-        pci_enable_msi(pdev);
+        ret = pci_enable_msi(pdev);
+        if (!ret) {
+                dev_info(&pdev->dev, "MSI enabled\n");
+                pci_set_master(pdev);
+        }
 
         addr = pci_iomap(pdev, 0, pci_resource_len(pdev, 0));
         if (!addr) {
@@ -132,6 +135,8 @@ static int c_can_pci_probe(struct pci_dev *pdev,
                 goto out_free_c_can;
         }
 
+        priv->type = c_can_pci_data->type;
+
         /* Configure access to registers */
         switch (c_can_pci_data->reg_align) {
         case C_CAN_REG_ALIGN_32:
diff --git a/drivers/net/can/c_can/c_can_platform.c b/drivers/net/can/c_can/c_can_platform.c
index 806d92753427..1df0b322d1e4 100644
--- a/drivers/net/can/c_can/c_can_platform.c
+++ b/drivers/net/can/c_can/c_can_platform.c
@@ -222,7 +222,7 @@ static int c_can_plat_probe(struct platform_device *pdev)
 
                 res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
                 priv->raminit_ctrlreg = devm_ioremap_resource(&pdev->dev, res);
-                if (IS_ERR(priv->raminit_ctrlreg) || (int)priv->instance < 0)
+                if (IS_ERR(priv->raminit_ctrlreg) || priv->instance < 0)
                         dev_info(&pdev->dev, "control memory is not used for raminit\n");
                 else
                         priv->raminit = c_can_hw_raminit;
diff --git a/drivers/net/can/dev.c b/drivers/net/can/dev.c
index c7a260478749..e318e87e2bfc 100644
--- a/drivers/net/can/dev.c
+++ b/drivers/net/can/dev.c
@@ -256,7 +256,7 @@ static int can_get_bittiming(struct net_device *dev, struct can_bittiming *bt,
 
         /* Check if the CAN device has bit-timing parameters */
         if (!btc)
-                return -ENOTSUPP;
+                return -EOPNOTSUPP;
 
         /*
          * Depending on the given can_bittiming parameter structure the CAN
diff --git a/drivers/net/can/sja1000/sja1000_isa.c b/drivers/net/can/sja1000/sja1000_isa.c
index df136a2516c4..014695d7e6a3 100644
--- a/drivers/net/can/sja1000/sja1000_isa.c
+++ b/drivers/net/can/sja1000/sja1000_isa.c
@@ -46,6 +46,7 @@ static int clk[MAXDEV];
 static unsigned char cdr[MAXDEV] = {[0 ... (MAXDEV - 1)] = 0xff};
 static unsigned char ocr[MAXDEV] = {[0 ... (MAXDEV - 1)] = 0xff};
 static int indirect[MAXDEV] = {[0 ... (MAXDEV - 1)] = -1};
+static spinlock_t indirect_lock[MAXDEV];  /* lock for indirect access mode */
 
 module_param_array(port, ulong, NULL, S_IRUGO);
 MODULE_PARM_DESC(port, "I/O port number");
@@ -101,19 +102,26 @@ static void sja1000_isa_port_write_reg(const struct sja1000_priv *priv,
 static u8 sja1000_isa_port_read_reg_indirect(const struct sja1000_priv *priv,
                                              int reg)
 {
-        unsigned long base = (unsigned long)priv->reg_base;
+        unsigned long flags, base = (unsigned long)priv->reg_base;
+        u8 readval;
 
+        spin_lock_irqsave(&indirect_lock[priv->dev->dev_id], flags);
         outb(reg, base);
-        return inb(base + 1);
+        readval = inb(base + 1);
+        spin_unlock_irqrestore(&indirect_lock[priv->dev->dev_id], flags);
+
+        return readval;
 }
 
 static void sja1000_isa_port_write_reg_indirect(const struct sja1000_priv *priv,
                                                 int reg, u8 val)
 {
-        unsigned long base = (unsigned long)priv->reg_base;
+        unsigned long flags, base = (unsigned long)priv->reg_base;
 
+        spin_lock_irqsave(&indirect_lock[priv->dev->dev_id], flags);
         outb(reg, base);
         outb(val, base + 1);
+        spin_unlock_irqrestore(&indirect_lock[priv->dev->dev_id], flags);
 }
 
 static int sja1000_isa_probe(struct platform_device *pdev)
@@ -169,6 +177,7 @@ static int sja1000_isa_probe(struct platform_device *pdev)
                 if (iosize == SJA1000_IOSIZE_INDIRECT) {
                         priv->read_reg = sja1000_isa_port_read_reg_indirect;
                         priv->write_reg = sja1000_isa_port_write_reg_indirect;
+                        spin_lock_init(&indirect_lock[idx]);
                 } else {
                         priv->read_reg = sja1000_isa_port_read_reg;
                         priv->write_reg = sja1000_isa_port_write_reg;
@@ -198,6 +207,7 @@ static int sja1000_isa_probe(struct platform_device *pdev)
 
         platform_set_drvdata(pdev, dev);
         SET_NETDEV_DEV(dev, &pdev->dev);
+        dev->dev_id = idx;
 
         err = register_sja1000dev(dev);
         if (err) {
diff --git a/drivers/net/can/slcan.c b/drivers/net/can/slcan.c
index f5b16e0e3a12..dcf9196f6316 100644
--- a/drivers/net/can/slcan.c
+++ b/drivers/net/can/slcan.c
@@ -322,13 +322,13 @@ static void slcan_write_wakeup(struct tty_struct *tty)
         if (!sl || sl->magic != SLCAN_MAGIC || !netif_running(sl->dev))
                 return;
 
-        spin_lock(&sl->lock);
+        spin_lock_bh(&sl->lock);
         if (sl->xleft <= 0)  {
                 /* Now serial buffer is almost free & we can start
                  * transmission of another packet */
                 sl->dev->stats.tx_packets++;
                 clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
-                spin_unlock(&sl->lock);
+                spin_unlock_bh(&sl->lock);
                 netif_wake_queue(sl->dev);
                 return;
         }
@@ -336,7 +336,7 @@ static void slcan_write_wakeup(struct tty_struct *tty)
         actual = tty->ops->write(tty, sl->xhead, sl->xleft);
         sl->xleft -= actual;
         sl->xhead += actual;
-        spin_unlock(&sl->lock);
+        spin_unlock_bh(&sl->lock);
 }
 
 /* Send a can_frame to a TTY queue. */