From: Richard Weinberger <richard@xxxxxx>
Signed-off-by: Richard Weinberger <richard@xxxxxx>
---
include/uapi/linux/can.h | 7 +-
include/uapi/linux/can/lin.h | 15 +++
net/can/Kconfig | 5 +
net/can/Makefile | 3 +
net/can/lin.c | 207 +++++++++++++++++++++++++++++++++++
5 files changed, 236 insertions(+), 1 deletion(-)
create mode 100644 include/uapi/linux/can/lin.h
create mode 100644 net/can/lin.c
diff --git a/include/uapi/linux/can.h b/include/uapi/linux/can.h
index 8596f9b23c68..73526805dc5f 100644
--- a/include/uapi/linux/can.h
+++ b/include/uapi/linux/can.h
@@ -178,7 +178,8 @@ struct canfd_frame {
#define CAN_MCNET 5 /* Bosch MCNet */
#define CAN_ISOTP 6 /* ISO 15765-2 Transport Protocol */
#define CAN_J1939 7 /* SAE J1939 */
-#define CAN_NPROTO 8
+#define CAN_LIN 8 /* LIN Bus */
+#define CAN_NPROTO 9
#define SOL_CAN_BASE 100
@@ -212,6 +213,10 @@ struct sockaddr_can {
__u8 addr;
} j1939;
+ struct {
+ __u8 addr; //Dummy for now
+ } lin;
+
/* reserved for future CAN protocols address information */
} can_addr;
};
diff --git a/include/uapi/linux/can/lin.h b/include/uapi/linux/can/lin.h
new file mode 100644
index 000000000000..7e9f44992b7d
--- /dev/null
+++ b/include/uapi/linux/can/lin.h
@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: (GPL-2.0-only WITH Linux-syscall-note) */
+/*
+ * linux/can/lin.h
+ * TODO
+ */
+
+#ifndef _UAPI_CAN_LIN_H
+#define _UAPI_CAN_LIN_H
+
+#include <linux/types.h>
+#include <linux/can.h>
+
+#define SOL_CAN_LIN (SOL_CAN_BASE + CAN_LIN)
+
+#endif /* !_UAPI_CAN_LIN_H */
diff --git a/net/can/Kconfig b/net/can/Kconfig
index cb56be8e3862..d05e3fa813e2 100644
--- a/net/can/Kconfig
+++ b/net/can/Kconfig
@@ -70,4 +70,9 @@ config CAN_ISOTP
If you want to perform automotive vehicle diagnostic services (UDS),
say 'y'.
+config CAN_LIN
+ tristate "Support for LIN bus"
+ help
+ TODO
+
endif
diff --git a/net/can/Makefile b/net/can/Makefile
index 58f2c31c1ef3..5db51a56a78a 100644
--- a/net/can/Makefile
+++ b/net/can/Makefile
@@ -20,3 +20,6 @@ obj-$(CONFIG_CAN_J1939) += j1939/
obj-$(CONFIG_CAN_ISOTP) += can-isotp.o
can-isotp-y := isotp.o
+
+obj-$(CONFIG_CAN_LIN) += can-lin.o
+can-lin-y := lin.o
diff --git a/net/can/lin.c b/net/can/lin.c
new file mode 100644
index 000000000000..f8c8217efc8c
--- /dev/null
+++ b/net/can/lin.c
@@ -0,0 +1,207 @@
+// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
+
+//TODO copyright
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/spinlock.h>
+#include <linux/hrtimer.h>
+#include <linux/wait.h>
+#include <linux/uio.h>
+#include <linux/net.h>
+#include <linux/netdevice.h>
+#include <linux/socket.h>
+#include <linux/if_arp.h>
+#include <linux/skbuff.h>
+#include <linux/can.h>
+#include <linux/can/core.h>
+#include <linux/can/skb.h>
+#include <linux/can/lin.h>
+#include <linux/slab.h>
+#include <net/sock.h>
+#include <net/net_namespace.h>
+
+MODULE_DESCRIPTION("PF_CAN LIN protocol");
+MODULE_LICENSE("GPLv2");
+MODULE_ALIAS("can-proto-8");
+
+struct lin_sock {
+ struct sock sk;
+};
+
+static inline struct lin_sock *lin_sk(const struct sock *sk)
+{
+ return (struct lin_sock *)sk;
+}
+
+static int lin_release(struct socket *sock)
+{
+ struct sock *sk = sock->sk;
+ struct lin_sock *so;
+ struct net *net;
+
+ if (!sk)
+ return 0;
+
+ so = lin_sk(sk);
+ net = sock_net(sk);
+
+ // Nothing do to so far
+
+ sock_orphan(sk);
+ sock->sk = NULL;
+
+ release_sock(sk);
+ sock_put(sk);
+
+ return 0;
+}
+
+static int lin_bind(struct socket *sock, struct sockaddr *uaddr, int len)
+{
+ struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
+ struct sock *sk = sock->sk;
+ struct net *net = sock_net(sk);
+ struct net_device *dev;
+ int err = 0;
+
+ //TODO
+ dev = dev_get_by_index(net, addr->can_ifindex);
+ if (!dev) {
+ err = -ENODEV;
+ goto out;
+ }
+ if (dev->type != ARPHRD_CAN) {
+ dev_put(dev);
+ err = -ENODEV;
+ goto out;
+ }
+
+out:
+ return err;
+}
+
+static int lin_setsockopt_locked(struct socket *sock, int level, int optname,
+ sockptr_t optval, unsigned int optlen)
+{
+ struct sock *sk = sock->sk;
+ struct lin_sock *so = lin_sk(sk);
+ int ret = 0;
+
+ (void)so;
+
+ switch (optname) {
+ // Nothing to do so far
+ default:
+ ret = -ENOPROTOOPT;
+ }
+
+ return ret;
+}
+
+static int lin_setsockopt(struct socket *sock, int level, int optname,
+ sockptr_t optval, unsigned int optlen)
+
+{
+ struct sock *sk = sock->sk;
+ int ret;
+
+ if (level != SOL_CAN_LIN)
+ return -EINVAL;
+
+ lock_sock(sk);
+ ret = lin_setsockopt_locked(sock, level, optname, optval, optlen);
+ release_sock(sk);
+ return ret;
+}
+
+static int lin_getsockopt(struct socket *sock, int level, int optname,
+ char __user *optval, int __user *optlen)
+{
+ struct sock *sk = sock->sk;
+ struct lin_sock *so = lin_sk(sk);
+ int len;
+ void *val;
+
+ (void)so;
+
+ if (level != SOL_CAN_LIN)
+ return -EINVAL;
+ if (get_user(len, optlen))
+ return -EFAULT;
+ if (len < 0)
+ return -EINVAL;
+
+ switch (optname) {
+ //Nothing to do so far.
+ default:
+ return -ENOPROTOOPT;
+ }
+
+ if (put_user(len, optlen))
+ return -EFAULT;
+ if (copy_to_user(optval, val, len))
+ return -EFAULT;
+ return 0;
+}
+
+static int lin_init(struct sock *sk)
+{
+ struct lin_sock *so = lin_sk(sk);
+
+ (void)so;
+ // Nothing to do so far
+
+ return 0;
+}
+
+static const struct proto_ops lin_ops = {
+ .family = PF_CAN,
+ .release = lin_release,
+ .bind = lin_bind,
+ .connect = sock_no_connect,
+ .socketpair = sock_no_socketpair,
+ .accept = sock_no_accept,
+ .getname = sock_no_getname,
+ .poll = datagram_poll,
+ .ioctl = sock_no_ioctl,
+ .gettstamp = sock_gettstamp,
+ .listen = sock_no_listen,
+ .shutdown = sock_no_shutdown,
+ .setsockopt = lin_setsockopt,
+ .getsockopt = lin_getsockopt,
+ .sendmsg = sock_no_sendmsg,
+ .recvmsg = sock_no_recvmsg,
+ .mmap = sock_no_mmap,
+ .sendpage = sock_no_sendpage,
+};
+
+static struct proto lin_proto __read_mostly = {
+ .name = "CAN_LIN",
+ .owner = THIS_MODULE,
+ .obj_size = sizeof(struct lin_sock),
+ .init = lin_init,
+};
+
+static const struct can_proto lin_can_proto = {
+ .type = SOCK_DGRAM,
+ .protocol = CAN_LIN,
+ .ops = &lin_ops,
+ .prot = &lin_proto,
+};
+
+static __init int lin_module_init(void)
+{
+ pr_info("can: lin protocol\n");
+
+ return can_proto_register(&lin_can_proto);
+}
+
+static __exit void lin_module_exit(void)
+{
+ can_proto_unregister(&lin_can_proto);
+}
+
+module_init(lin_module_init);
+module_exit(lin_module_exit);
--
2.30.2
