@@ -4,6 +4,9 @@
Frame Relay (FR)
================
+Note that the Frame Relay layer is deprecated. New drivers should use the HDLC
+Frame Relay layer instead.
+
Frame Relay (FR) support for linux is built into a two tiered system of device
drivers. The upper layer implements RFC1490 FR specification, and uses the
Data Link Connection Identifier (DLCI) as its hardware address. Usually these
@@ -514,6 +514,8 @@ static int __init init_dlci(void)
register_netdevice_notifier(&dlci_notifier);
printk("%s.\n", version);
+ pr_warn("The DLCI driver (the Frame Relay layer) is deprecated.\n"
+ "Please move your driver to using the HDLC Frame Relay instead.\n");
return 0;
}
@@ -1623,6 +1623,9 @@ static int __init init_sdla(void)
int err;
printk("%s.\n", version);
+ pr_warn("The SDLA driver is deprecated.\n"
+ "If you are still using the hardware,\n"
+ "please help move this driver to using the HDLC Frame Relay layer.\n");
sdla = alloc_netdev(sizeof(struct frad_local), "sdla0",
NET_NAME_UNKNOWN, setup_sdla);
I wish to deprecate the Frame Relay layer (dlci.c) in the kernel because we already have a newer and better "HDLC Frame Relay" layer (hdlc_fr.c). Reasons why hdlc_fr.c is better than dlci.c include: 1. dlci.c is dated 1997, while hdlc_fr.c is dated 1999 - 2006, so the later is newer than the former. 2. hdlc_fr.c is working well (tested by me). For dlci.c, I cannot even find the user space problem needed to use it. The link provided in Documentation/networking/framerelay.rst (in the last paragraph) is no longer valid. 3. dlci.c supports only one hardware driver - sdla.c, while hdlc_fr.c supports many hardware drivers through the generic HDLC layer (hdlc.c). WAN hardware devices are usually able to support several L2 protocols at the same time, so the HDLC layer is more suitable for these devices. The hardware devices that sdla.c supports are also multi-protocol (according to drivers/net/wan/Kconfig), so the HDLC layer is more suitable for these devices, too. 4. hdlc_fr.c supports LMI and supports Ethernet emulation. dlci.c supports neither according to its code. 5. include/uapi/linux/if_frad.h, which comes with dlci.c, contains two structs for ioctl configs (dlci_conf and frad_conf). According to the comments, these two structs are specially crafted for sdla.c (the only hardware driver dlci.c supports). I think this makes dlci.c not generic enough to support other hardware drivers. Cc: Lee Jones <lee.jones@linaro.org> Cc: Gustavo A. R. Silva <gustavoars@kernel.org> Cc: Krzysztof Kozlowski <krzk@kernel.org> Signed-off-by: Xie He <xie.he.0141@gmail.com> --- Documentation/networking/framerelay.rst | 3 +++ drivers/net/wan/dlci.c | 2 ++ drivers/net/wan/sdla.c | 3 +++ 3 files changed, 8 insertions(+)