summaryrefslogtreecommitdiff
path: root/drivers/net/can
diff options
context:
space:
mode:
authorTomoya <tomoya-linux@dsn.okisemi.com>2010-12-12 23:24:12 +0300
committerDavid S. Miller <davem@davemloft.net>2010-12-13 23:24:21 +0300
commitbd58cbc322e97550af5e12584324b7117180435d (patch)
treeb39c36558b01f62372ea574b2384ac10800c8e92 /drivers/net/can
parent7f2bc50efeaeb1dff62ef7e128ae36499fbcf35d (diff)
downloadlinux-bd58cbc322e97550af5e12584324b7117180435d.tar.xz
pch_can: Rename function/macro name
For easy to read/understand, Rename function/macro name. Signed-off-by: Tomoya MORINAGA <tomoya-linux@dsn.okisemi.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/can')
-rw-r--r--drivers/net/can/pch_can.c176
1 files changed, 77 insertions, 99 deletions
diff --git a/drivers/net/can/pch_can.c b/drivers/net/can/pch_can.c
index 5fc99cb10df0..dd9ce16635b3 100644
--- a/drivers/net/can/pch_can.c
+++ b/drivers/net/can/pch_can.c
@@ -32,8 +32,6 @@
#include <linux/can/dev.h>
#include <linux/can/error.h>
-#define PCH_ENABLE 1 /* The enable flag */
-#define PCH_DISABLE 0 /* The disable flag */
#define PCH_CTRL_INIT BIT(0) /* The INIT bit of CANCONT register. */
#define PCH_CTRL_IE BIT(1) /* The IE bit of CAN control register */
#define PCH_CTRL_IE_SIE_EIE (BIT(3) | BIT(2) | BIT(1))
@@ -78,11 +76,12 @@
#define PCH_BUS_OFF BIT(7)
/* bit position of certain controller bits. */
-#define PCH_BIT_BRP 0
-#define PCH_BIT_SJW 6
-#define PCH_BIT_TSEG1 8
-#define PCH_BIT_TSEG2 12
-#define PCH_BIT_BRPE_BRPE 6
+#define PCH_BIT_BRP_SHIFT 0
+#define PCH_BIT_SJW_SHIFT 6
+#define PCH_BIT_TSEG1_SHIFT 8
+#define PCH_BIT_TSEG2_SHIFT 12
+#define PCH_BIT_BRPE_BRPE_SHIFT 6
+
#define PCH_MSK_BITT_BRP 0x3f
#define PCH_MSK_BRPE_BRPE 0x3c0
#define PCH_MSK_CTRL_IE_SIE_EIE 0x07
@@ -170,19 +169,16 @@ struct pch_can_regs {
struct pch_can_priv {
struct can_priv can;
- unsigned int can_num;
struct pci_dev *dev;
- int tx_enable[PCH_TX_OBJ_END];
- int rx_enable[PCH_TX_OBJ_END];
- int rx_link[PCH_TX_OBJ_END];
- unsigned int int_enables;
- unsigned int int_stat;
+ u32 tx_enable[PCH_TX_OBJ_END];
+ u32 rx_enable[PCH_TX_OBJ_END];
+ u32 rx_link[PCH_TX_OBJ_END];
+ u32 int_enables;
struct net_device *ndev;
- unsigned int msg_obj[PCH_TX_OBJ_END];
struct pch_can_regs __iomem *regs;
struct napi_struct napi;
- unsigned int tx_obj; /* Point next Tx Obj index */
- unsigned int use_msi;
+ int tx_obj; /* Point next Tx Obj index */
+ int use_msi;
};
static struct can_bittiming_const pch_can_bittiming_const = {
@@ -245,14 +241,27 @@ static void pch_can_set_optmode(struct pch_can_priv *priv)
iowrite32(reg_val, &priv->regs->opt);
}
+static void pch_can_rw_msg_obj(void __iomem *creq_addr, u32 num)
+{
+ int counter = PCH_COUNTER_LIMIT;
+ u32 ifx_creq;
+
+ iowrite32(num, creq_addr);
+ while (counter) {
+ ifx_creq = ioread32(creq_addr) & PCH_IF_CREQ_BUSY;
+ if (!ifx_creq)
+ break;
+ counter--;
+ udelay(1);
+ }
+ if (!counter)
+ pr_err("%s:IF1 BUSY Flag is set forever.\n", __func__);
+}
+
static void pch_can_set_int_enables(struct pch_can_priv *priv,
enum pch_can_mode interrupt_no)
{
switch (interrupt_no) {
- case PCH_CAN_ENABLE:
- pch_can_bit_set(&priv->regs->cont, PCH_CTRL_IE);
- break;
-
case PCH_CAN_DISABLE:
pch_can_bit_clear(&priv->regs->cont, PCH_CTRL_IE);
break;
@@ -271,25 +280,8 @@ static void pch_can_set_int_enables(struct pch_can_priv *priv,
}
}
-static void pch_can_check_if_busy(u32 __iomem *creq_addr, u32 num)
-{
- u32 counter = PCH_COUNTER_LIMIT;
- u32 ifx_creq;
-
- iowrite32(num, creq_addr);
- while (counter) {
- ifx_creq = ioread32(creq_addr) & PCH_IF_CREQ_BUSY;
- if (!ifx_creq)
- break;
- counter--;
- udelay(1);
- }
- if (!counter)
- pr_err("%s:IF1 BUSY Flag is set forever.\n", __func__);
-}
-
static void pch_can_set_rxtx(struct pch_can_priv *priv, u32 buff_num,
- u32 set, enum pch_ifreg dir)
+ int set, enum pch_ifreg dir)
{
u32 ie;
@@ -300,27 +292,27 @@ static void pch_can_set_rxtx(struct pch_can_priv *priv, u32 buff_num,
/* Reading the receive buffer data from RAM to Interface1 registers */
iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[dir].cmask);
- pch_can_check_if_busy(&priv->regs->ifregs[dir].creq, buff_num);
+ pch_can_rw_msg_obj(&priv->regs->ifregs[dir].creq, buff_num);
/* Setting the IF1MASK1 register to access MsgVal and RxIE bits */
iowrite32(PCH_CMASK_RDWR | PCH_CMASK_ARB | PCH_CMASK_CTRL,
&priv->regs->ifregs[dir].cmask);
- if (set == PCH_ENABLE) {
+ if (set) {
/* Setting the MsgVal and RxIE bits */
pch_can_bit_set(&priv->regs->ifregs[dir].mcont, ie);
pch_can_bit_set(&priv->regs->ifregs[dir].id2, PCH_ID_MSGVAL);
- } else if (set == PCH_DISABLE) {
+ } else {
/* Resetting the MsgVal and RxIE bits */
pch_can_bit_clear(&priv->regs->ifregs[dir].mcont, ie);
pch_can_bit_clear(&priv->regs->ifregs[dir].id2, PCH_ID_MSGVAL);
}
- pch_can_check_if_busy(&priv->regs->ifregs[dir].creq, buff_num);
+ pch_can_rw_msg_obj(&priv->regs->ifregs[dir].creq, buff_num);
}
-static void pch_can_set_rx_all(struct pch_can_priv *priv, u32 set)
+static void pch_can_set_rx_all(struct pch_can_priv *priv, int set)
{
int i;
@@ -329,7 +321,7 @@ static void pch_can_set_rx_all(struct pch_can_priv *priv, u32 set)
pch_can_set_rxtx(priv, i, set, PCH_RX_IFREG);
}
-static void pch_can_set_tx_all(struct pch_can_priv *priv, u32 set)
+static void pch_can_set_tx_all(struct pch_can_priv *priv, int set)
{
int i;
@@ -338,16 +330,16 @@ static void pch_can_set_tx_all(struct pch_can_priv *priv, u32 set)
pch_can_set_rxtx(priv, i, set, PCH_TX_IFREG);
}
-static int pch_can_int_pending(struct pch_can_priv *priv)
+static u32 pch_can_int_pending(struct pch_can_priv *priv)
{
return ioread32(&priv->regs->intr) & 0xffff;
}
-static void pch_can_clear_buffers(struct pch_can_priv *priv)
+static void pch_can_clear_if_buffers(struct pch_can_priv *priv)
{
- int i;
+ int i; /* Msg Obj ID (1~32) */
- for (i = PCH_RX_OBJ_START; i <= PCH_RX_OBJ_END; i++) {
+ for (i = PCH_RX_OBJ_START; i <= PCH_TX_OBJ_END; i++) {
iowrite32(PCH_CMASK_RX_TX_SET, &priv->regs->ifregs[0].cmask);
iowrite32(0xffff, &priv->regs->ifregs[0].mask1);
iowrite32(0xffff, &priv->regs->ifregs[0].mask2);
@@ -361,24 +353,7 @@ static void pch_can_clear_buffers(struct pch_can_priv *priv)
iowrite32(PCH_CMASK_RDWR | PCH_CMASK_MASK |
PCH_CMASK_ARB | PCH_CMASK_CTRL,
&priv->regs->ifregs[0].cmask);
- pch_can_check_if_busy(&priv->regs->ifregs[0].creq, i);
- }
-
- for (i = PCH_TX_OBJ_START; i <= PCH_TX_OBJ_END; i++) {
- iowrite32(PCH_CMASK_RX_TX_SET, &priv->regs->ifregs[1].cmask);
- iowrite32(0xffff, &priv->regs->ifregs[1].mask1);
- iowrite32(0xffff, &priv->regs->ifregs[1].mask2);
- iowrite32(0x0, &priv->regs->ifregs[1].id1);
- iowrite32(0x0, &priv->regs->ifregs[1].id2);
- iowrite32(0x0, &priv->regs->ifregs[1].mcont);
- iowrite32(0x0, &priv->regs->ifregs[1].data[0]);
- iowrite32(0x0, &priv->regs->ifregs[1].data[1]);
- iowrite32(0x0, &priv->regs->ifregs[1].data[2]);
- iowrite32(0x0, &priv->regs->ifregs[1].data[3]);
- iowrite32(PCH_CMASK_RDWR | PCH_CMASK_MASK |
- PCH_CMASK_ARB | PCH_CMASK_CTRL,
- &priv->regs->ifregs[1].cmask);
- pch_can_check_if_busy(&priv->regs->ifregs[1].creq, i);
+ pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, i);
}
}
@@ -389,7 +364,7 @@ static void pch_can_config_rx_tx_buffers(struct pch_can_priv *priv)
for (i = PCH_RX_OBJ_START; i <= PCH_RX_OBJ_END; i++) {
iowrite32(PCH_CMASK_RX_TX_GET,
&priv->regs->ifregs[0].cmask);
- pch_can_check_if_busy(&priv->regs->ifregs[0].creq, i);
+ pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, i);
iowrite32(0x0, &priv->regs->ifregs[0].id1);
iowrite32(0x0, &priv->regs->ifregs[0].id2);
@@ -403,6 +378,9 @@ static void pch_can_config_rx_tx_buffers(struct pch_can_priv *priv)
/* In case FIFO mode, Last EoB of Rx Obj must be 1 */
if (i == PCH_RX_OBJ_END)
pch_can_bit_set(&priv->regs->ifregs[0].mcont,
+ PCH_IF_MCONT_EOB);
+ else
+ pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
PCH_IF_MCONT_EOB);
iowrite32(0, &priv->regs->ifregs[0].mask1);
@@ -414,13 +392,13 @@ static void pch_can_config_rx_tx_buffers(struct pch_can_priv *priv)
PCH_CMASK_ARB | PCH_CMASK_CTRL,
&priv->regs->ifregs[0].cmask);
- pch_can_check_if_busy(&priv->regs->ifregs[0].creq, i);
+ pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, i);
}
for (i = PCH_TX_OBJ_START; i <= PCH_TX_OBJ_END; i++) {
iowrite32(PCH_CMASK_RX_TX_GET,
&priv->regs->ifregs[1].cmask);
- pch_can_check_if_busy(&priv->regs->ifregs[1].creq, i);
+ pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, i);
/* Resetting DIR bit for reception */
iowrite32(0x0, &priv->regs->ifregs[1].id1);
@@ -441,7 +419,7 @@ static void pch_can_config_rx_tx_buffers(struct pch_can_priv *priv)
PCH_CMASK_ARB | PCH_CMASK_CTRL,
&priv->regs->ifregs[1].cmask);
- pch_can_check_if_busy(&priv->regs->ifregs[1].creq, i);
+ pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, i);
}
}
@@ -451,7 +429,7 @@ static void pch_can_init(struct pch_can_priv *priv)
pch_can_set_run_mode(priv, PCH_CAN_STOP);
/* Clearing all the message object buffers. */
- pch_can_clear_buffers(priv);
+ pch_can_clear_if_buffers(priv);
/* Configuring the respective message object as either rx/tx object. */
pch_can_config_rx_tx_buffers(priv);
@@ -496,7 +474,7 @@ static void pch_can_int_clr(struct pch_can_priv *priv, u32 mask)
pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
PCH_IF_MCONT_NEWDAT | PCH_IF_MCONT_INTPND);
- pch_can_check_if_busy(&priv->regs->ifregs[0].creq, mask);
+ pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, mask);
} else if ((mask >= PCH_TX_OBJ_START) && (mask <= PCH_TX_OBJ_END)) {
/* Setting CMASK for clearing interrupts for
frame transmission. */
@@ -512,7 +490,7 @@ static void pch_can_int_clr(struct pch_can_priv *priv, u32 mask)
pch_can_bit_clear(&priv->regs->ifregs[1].mcont,
PCH_IF_MCONT_NEWDAT | PCH_IF_MCONT_INTPND |
PCH_IF_MCONT_TXRQXT);
- pch_can_check_if_busy(&priv->regs->ifregs[1].creq, mask);
+ pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, mask);
}
}
@@ -637,7 +615,7 @@ static void pch_fifo_thresh(struct pch_can_priv *priv, int obj_id)
/* Clearing NewDat & IntPnd */
pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
PCH_IF_MCONT_INTPND);
- pch_can_check_if_busy(&priv->regs->ifregs[0].creq, obj_id);
+ pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, obj_id);
} else if (obj_id > PCH_FIFO_THRESH) {
pch_can_int_clr(priv, obj_id);
} else if (obj_id == PCH_FIFO_THRESH) {
@@ -659,7 +637,7 @@ static void pch_can_rx_msg_lost(struct net_device *ndev, int obj_id)
PCH_IF_MCONT_MSGLOST);
iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL,
&priv->regs->ifregs[0].cmask);
- pch_can_check_if_busy(&priv->regs->ifregs[0].creq, obj_id);
+ pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, obj_id);
skb = alloc_can_err_skb(ndev, &cf);
if (!skb)
@@ -689,7 +667,7 @@ static int pch_can_rx_normal(struct net_device *ndev, u32 obj_num, int quota)
do {
/* Reading the messsage object from the Message RAM */
iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[0].cmask);
- pch_can_check_if_busy(&priv->regs->ifregs[0].creq, obj_num);
+ pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, obj_num);
/* Reading the MCONT register. */
reg = ioread32(&priv->regs->ifregs[0].mcont);
@@ -758,7 +736,7 @@ static void pch_can_tx_complete(struct net_device *ndev, u32 int_stat)
can_get_echo_skb(ndev, int_stat - PCH_RX_OBJ_END - 1);
iowrite32(PCH_CMASK_RX_TX_GET | PCH_CMASK_CLRINTPND,
&priv->regs->ifregs[1].cmask);
- pch_can_check_if_busy(&priv->regs->ifregs[1].creq, int_stat);
+ pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, int_stat);
dlc = get_can_dlc(ioread32(&priv->regs->ifregs[1].mcont) &
PCH_IF_MCONT_DLC);
stats->tx_bytes += dlc;
@@ -767,7 +745,7 @@ static void pch_can_tx_complete(struct net_device *ndev, u32 int_stat)
netif_wake_queue(ndev);
}
-static int pch_can_rx_poll(struct napi_struct *napi, int quota)
+static int pch_can_poll(struct napi_struct *napi, int quota)
{
struct net_device *ndev = napi->dev;
struct pch_can_priv *priv = netdev_priv(ndev);
@@ -832,10 +810,10 @@ static int pch_set_bittiming(struct net_device *ndev)
brp = (bt->tq) / (1000000000/PCH_CAN_CLK) - 1;
canbit = brp & PCH_MSK_BITT_BRP;
- canbit |= (bt->sjw - 1) << PCH_BIT_SJW;
- canbit |= (bt->phase_seg1 + bt->prop_seg - 1) << PCH_BIT_TSEG1;
- canbit |= (bt->phase_seg2 - 1) << PCH_BIT_TSEG2;
- bepe = (brp & PCH_MSK_BRPE_BRPE) >> PCH_BIT_BRPE_BRPE;
+ canbit |= (bt->sjw - 1) << PCH_BIT_SJW_SHIFT;
+ canbit |= (bt->phase_seg1 + bt->prop_seg - 1) << PCH_BIT_TSEG1_SHIFT;
+ canbit |= (bt->phase_seg2 - 1) << PCH_BIT_TSEG2_SHIFT;
+ bepe = (brp & PCH_MSK_BRPE_BRPE) >> PCH_BIT_BRPE_BRPE_SHIFT;
iowrite32(canbit, &priv->regs->bitt);
iowrite32(bepe, &priv->regs->brpe);
pch_can_bit_clear(&priv->regs->cont, PCH_CTRL_CCE);
@@ -947,7 +925,7 @@ static netdev_tx_t pch_xmit(struct sk_buff *skb, struct net_device *ndev)
{
struct pch_can_priv *priv = netdev_priv(ndev);
struct can_frame *cf = (struct can_frame *)skb->data;
- int tx_buffer_avail = 0;
+ int tx_obj_no;
int i;
if (can_dropped_invalid_skb(ndev, skb))
@@ -957,16 +935,16 @@ static netdev_tx_t pch_xmit(struct sk_buff *skb, struct net_device *ndev)
if (ioread32(&priv->regs->treq2) & PCH_TREQ2_TX_MASK)
netif_stop_queue(ndev);
- tx_buffer_avail = priv->tx_obj;
+ tx_obj_no = priv->tx_obj;
priv->tx_obj = PCH_TX_OBJ_START;
} else {
- tx_buffer_avail = priv->tx_obj;
+ tx_obj_no = priv->tx_obj;
priv->tx_obj++;
}
/* Reading the Msg Obj from the Msg RAM to the Interface register. */
iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[1].cmask);
- pch_can_check_if_busy(&priv->regs->ifregs[1].creq, tx_buffer_avail);
+ pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, tx_obj_no);
/* Setting the CMASK register. */
pch_can_bit_set(&priv->regs->ifregs[1].cmask, PCH_CMASK_ALL);
@@ -995,7 +973,7 @@ static netdev_tx_t pch_xmit(struct sk_buff *skb, struct net_device *ndev)
&priv->regs->ifregs[1].data[i / 2]);
}
- can_put_echo_skb(skb, ndev, tx_buffer_avail - PCH_RX_OBJ_END - 1);
+ can_put_echo_skb(skb, ndev, tx_obj_no - PCH_RX_OBJ_END - 1);
/* Updating the size of the data. */
pch_can_bit_clear(&priv->regs->ifregs[1].mcont, 0x0f);
@@ -1010,7 +988,7 @@ static netdev_tx_t pch_xmit(struct sk_buff *skb, struct net_device *ndev)
pch_can_bit_set(&priv->regs->ifregs[1].mcont,
PCH_IF_MCONT_NEWDAT | PCH_IF_MCONT_TXRQXT);
- pch_can_check_if_busy(&priv->regs->ifregs[1].creq, tx_buffer_avail);
+ pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, tx_obj_no);
return NETDEV_TX_OK;
}
@@ -1064,7 +1042,7 @@ static u32 pch_can_get_rxtx_ir(struct pch_can_priv *priv, u32 buff_num,
ie = PCH_IF_MCONT_TXIE;
iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[dir].cmask);
- pch_can_check_if_busy(&priv->regs->ifregs[dir].creq, buff_num);
+ pch_can_rw_msg_obj(&priv->regs->ifregs[dir].creq, buff_num);
if (((ioread32(&priv->regs->ifregs[dir].id2)) & PCH_ID_MSGVAL) &&
((ioread32(&priv->regs->ifregs[dir].mcont)) & ie)) {
@@ -1076,37 +1054,37 @@ static u32 pch_can_get_rxtx_ir(struct pch_can_priv *priv, u32 buff_num,
}
static void pch_can_set_rx_buffer_link(struct pch_can_priv *priv,
- u32 buffer_num, u32 set)
+ u32 buffer_num, int set)
{
iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[0].cmask);
- pch_can_check_if_busy(&priv->regs->ifregs[0].creq, buffer_num);
+ pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, buffer_num);
iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL,
&priv->regs->ifregs[0].cmask);
- if (set == PCH_ENABLE)
+ if (set)
pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
PCH_IF_MCONT_EOB);
else
pch_can_bit_set(&priv->regs->ifregs[0].mcont, PCH_IF_MCONT_EOB);
- pch_can_check_if_busy(&priv->regs->ifregs[0].creq, buffer_num);
+ pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, buffer_num);
}
static void pch_can_get_rx_buffer_link(struct pch_can_priv *priv,
u32 buffer_num, u32 *link)
{
iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[0].cmask);
- pch_can_check_if_busy(&priv->regs->ifregs[0].creq, buffer_num);
+ pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, buffer_num);
if (ioread32(&priv->regs->ifregs[0].mcont) & PCH_IF_MCONT_EOB)
- *link = PCH_DISABLE;
+ *link = 0;
else
- *link = PCH_ENABLE;
+ *link = 1;
}
static int pch_can_get_buffer_status(struct pch_can_priv *priv)
{
return (ioread32(&priv->regs->treq1) & 0xffff) |
- ((ioread32(&priv->regs->treq2) & 0xffff) << 16);
+ (ioread32(&priv->regs->treq2) << 16);
}
static int pch_can_suspend(struct pci_dev *pdev, pm_message_t state)
@@ -1114,7 +1092,7 @@ static int pch_can_suspend(struct pci_dev *pdev, pm_message_t state)
int i; /* Counter variable. */
int retval; /* Return value. */
u32 buf_stat; /* Variable for reading the transmit buffer status. */
- u32 counter = 0xFFFFFF;
+ int counter = PCH_COUNTER_LIMIT;
struct net_device *dev = pci_get_drvdata(pdev);
struct pch_can_priv *priv = netdev_priv(dev);
@@ -1291,7 +1269,7 @@ static int __devinit pch_can_probe(struct pci_dev *pdev,
ndev->netdev_ops = &pch_can_netdev_ops;
priv->can.clock.freq = PCH_CAN_CLK; /* Hz */
- netif_napi_add(ndev, &priv->napi, pch_can_rx_poll, PCH_RX_OBJ_END);
+ netif_napi_add(ndev, &priv->napi, pch_can_poll, PCH_RX_OBJ_END);
rc = register_candev(ndev);
if (rc) {