niansa-misc/linux
1
0
Fork 0
mirror of synced 2025-03-06 20:59:54 +01:00
Code Issues Projects Releases Packages Wiki Activity

can: slcan: extend the protocol with CAN state info

Browse source 
It extends the protocol to receive the adapter CAN state changes
(warning, busoff, etc.) and forward them to the netdev upper levels.

Link: https://lore.kernel.org/all/20220628163137.413025-13-dario.binacchi@amarulasolutions.com
Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This commit is contained in:
Dario Binacchi 2022-06-28 18:31:36 +02:00 • committed by Marc Kleine-Budde
parent b32ff46685
commit 0a9cdcf098
1 changed files with 73 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

74
drivers/net/can/slcan/slcan-core.c
View file

@ -78,7 +78,11 @@ MODULE_PARM_DESC(maxdev, "Maximum number of slcan interfaces");
#define SLC_CMD_LEN 1 #define SLC_CMD_LEN 1
#define SLC_SFF_ID_LEN 3 #define SLC_SFF_ID_LEN 3
#define SLC_EFF_ID_LEN 8 #define SLC_EFF_ID_LEN 8
#define SLC_STATE_LEN 1
#define SLC_STATE_BE_RXCNT_LEN 3
#define SLC_STATE_BE_TXCNT_LEN 3
#define SLC_STATE_FRAME_LEN (1 + SLC_CMD_LEN + SLC_STATE_BE_RXCNT_LEN + \
SLC_STATE_BE_TXCNT_LEN)
struct slcan { struct slcan {
struct can_priv can; struct can_priv can;
int magic; int magic;
@ -254,6 +258,72 @@ decode_failed:
dev_kfree_skb(skb); dev_kfree_skb(skb);
} }
/* A change state frame must contain state info and receive and transmit
* error counters.
*
* Examples:
*
* sb256256 : state bus-off: rx counter 256, tx counter 256
* sa057033 : state active, rx counter 57, tx counter 33
*/
static void slc_bump_state(struct slcan *sl)
{
struct net_device *dev = sl->dev;
struct sk_buff *skb;
struct can_frame *cf;
char *cmd = sl->rbuff;
u32 rxerr, txerr;
enum can_state state, rx_state, tx_state;
switch (cmd[1]) {
case 'a':
state = CAN_STATE_ERROR_ACTIVE;
break;
case 'w':
state = CAN_STATE_ERROR_WARNING;
break;
case 'p':
state = CAN_STATE_ERROR_PASSIVE;
break;
case 'b':
state = CAN_STATE_BUS_OFF;
break;
default:
return;
}
if (state == sl->can.state || sl->rcount < SLC_STATE_FRAME_LEN)
return;
cmd += SLC_STATE_BE_RXCNT_LEN + SLC_CMD_LEN + 1;
cmd[SLC_STATE_BE_TXCNT_LEN] = 0;
if (kstrtou32(cmd, 10, &txerr))
return;
*cmd = 0;
cmd -= SLC_STATE_BE_RXCNT_LEN;
if (kstrtou32(cmd, 10, &rxerr))
return;
skb = alloc_can_err_skb(dev, &cf);
if (skb) {
cf->data[6] = txerr;
cf->data[7] = rxerr;
} else {
cf = NULL;
}
tx_state = txerr >= rxerr ? state : 0;
rx_state = txerr <= rxerr ? state : 0;
can_change_state(dev, cf, tx_state, rx_state);
if (state == CAN_STATE_BUS_OFF)
can_bus_off(dev);
if (skb)
netif_rx(skb);
}
/* An error frame can contain more than one type of error. /* An error frame can contain more than one type of error.
* *
* Examples: * Examples:
@ -387,6 +457,8 @@ static void slc_bump(struct slcan *sl)
return slc_bump_frame(sl); return slc_bump_frame(sl);
case 'e': case 'e':
return slc_bump_err(sl); return slc_bump_err(sl);
case 's':
return slc_bump_state(sl);
default: default:
return; return;
} }