From: Yi Cong Some vendors' USB network interface controllers (NICs) may be compatible with multiple drivers. I consulted with relevant vendors. Taking the AX88179 chip as an example, NICs based on this chip may be used across various OS—for instance, cdc_ncm is used on macOS, while ax88179_178a.ko is the intended driver on Linux (despite a previous patch having disabled it). Therefore, the firmware must support multiple protocols. Currently, both cdc_ncm and ax88179_178a coexist in the Linux kernel. Supporting both drivers simultaneously leads to the following issues: 1. Inconsistent driver loading order during reboot stress testing: The order in which drivers are loaded can vary across reboots, potentially resulting in the unintended driver being loaded. For example: [ 4.239893] cdc_ncm 2-1:2.0: MAC-Address: c8:a3:62:ef:99:8e [ 4.239897] cdc_ncm 2-1:2.0: setting rx_max = 16384 [ 4.240149] cdc_ncm 2-1:2.0: setting tx_max = 16384 [ 4.240583] cdc_ncm 2-1:2.0 usb0: register 'cdc_ncm' at usb- xxxxx:00-1, CDC NCM, c8:a3:62:ef:99:8e [ 4.240627] usbcore: registered new interface driver cdc_ncm [ 4.240908] usbcore: registered new interface driver ax88179_178a In this case, network connectivity functions, but the cdc_ncm driver is loaded instead of the expected ax88179_178a. 2. Similar issues during cable plug/unplug testing: The same race condition can occur when reconnecting the USB device: [ 79.879922] usb 4-1: new SuperSpeed USB device number 3 using xhci_hcd [ 79.905168] usb 4-1: New USB device found, idVendor=0b95, idProduct= 1790, bcdDevice= 2.00 [ 79.905185] usb 4-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3 [ 79.905191] usb 4-1: Product: AX88179B [ 79.905198] usb 4-1: Manufacturer: ASIX [ 79.905201] usb 4-1: SerialNumber: 00EF998E [ 79.915215] ax88179_probe, bConfigurationValue:2 [ 79.952638] cdc_ncm 4-1:2.0: MAC-Address: c8:a3:62:ef:99:8e [ 79.952654] cdc_ncm 4-1:2.0: setting rx_max = 16384 [ 79.952919] cdc_ncm 4-1:2.0: setting tx_max = 16384 [ 79.953598] cdc_ncm 4-1:2.0 eth0: register 'cdc_ncm' at usb-0000:04: 00.2-1, CDC NCM (NO ZLP), c8:a3:62:ef:99:8e [ 79.954029] cdc_ncm 4-1:2.0 eth0: unregister 'cdc_ncm' usb-0000:04: 00.2-1, CDC NCM (NO ZLP) At this point, the network becomes unusable. To resolve these issues, introduce a *quirks* mechanism into the usbnet module. By adding chip-specific identification within the generic usbnet framework, we can skip the usbnet probe process for devices that require a dedicated driver. v2: Correct the description of usbnet_quirks.h and modify the code style v3: Add checking whether the CONFIG_USB_NET_AX88179_178A is enabled v4: Move quirks from usbnet.ko to cdc_ncm.ko Signed-off-by: Yi Cong --- drivers/net/usb/cdc_ncm.c | 15 +++++++++++- drivers/net/usb/cdc_ncm_quirks.h | 41 ++++++++++++++++++++++++++++++++ 2 files changed, 55 insertions(+), 1 deletion(-) create mode 100644 drivers/net/usb/cdc_ncm_quirks.h diff --git a/drivers/net/usb/cdc_ncm.c b/drivers/net/usb/cdc_ncm.c index 5d123df0a866..fc8416af3f11 100644 --- a/drivers/net/usb/cdc_ncm.c +++ b/drivers/net/usb/cdc_ncm.c @@ -54,6 +54,8 @@ #include #include +#include "cdc_ncm_quirks.h" + #if IS_ENABLED(CONFIG_USB_NET_CDC_MBIM) static bool prefer_mbim = true; #else @@ -2114,10 +2116,21 @@ static const struct usb_device_id cdc_devs[] = { }; MODULE_DEVICE_TABLE(usb, cdc_devs); +static int cdc_ncm_probe(struct usb_interface *intf, const struct usb_device_id *prod) +{ + /* Should it be ignored? */ + if (unlikely(cdc_ncm_ignore(intf))) { + dev_dbg(&intf->dev, "cdc_ncm ignore this device!\n"); + return -ENODEV; + } + + return usbnet_probe(intf, prod); +} + static struct usb_driver cdc_ncm_driver = { .name = "cdc_ncm", .id_table = cdc_devs, - .probe = usbnet_probe, + .probe = cdc_ncm_probe, .disconnect = usbnet_disconnect, .suspend = usbnet_suspend, .resume = usbnet_resume, diff --git a/drivers/net/usb/cdc_ncm_quirks.h b/drivers/net/usb/cdc_ncm_quirks.h new file mode 100644 index 000000000000..e5ae2265b1d7 --- /dev/null +++ b/drivers/net/usb/cdc_ncm_quirks.h @@ -0,0 +1,41 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * A collection of chip information to be ignored + */ + +#ifndef __CDC_NCM_IGNORE_H__ +#define __CDC_NCM_IGNORE_H__ + +#include + +/* cdc_ncm_ignore_list: + * Chip info which already support int vendor specific driver, + * and then should be ignored in generic cdc_ncm + */ +static const struct usb_device_id cdc_ncm_ignore_list[] = { +#if IS_ENABLED(CONFIG_USB_NET_AX88179_178A) + /* Chips already support in ax88179_178a.c */ + { USB_DEVICE(0x0b95, 0x1790) }, + { USB_DEVICE(0x0b95, 0x178a) }, + { USB_DEVICE(0x04b4, 0x3610) }, + { USB_DEVICE(0x2001, 0x4a00) }, + { USB_DEVICE(0x0df6, 0x0072) }, + { USB_DEVICE(0x04e8, 0xa100) }, + { USB_DEVICE(0x17ef, 0x304b) }, + { USB_DEVICE(0x050d, 0x0128) }, + { USB_DEVICE(0x0930, 0x0a13) }, + { USB_DEVICE(0x0711, 0x0179) }, + { USB_DEVICE(0x07c9, 0x000e) }, + { USB_DEVICE(0x07c9, 0x000f) }, + { USB_DEVICE(0x07c9, 0x0010) }, + /* End of support in ax88179_178a.c */ +#endif + + { } /*END*/ +}; + +static inline bool cdc_ncm_ignore(struct usb_interface *intf) +{ + return !!usb_match_id(intf, cdc_ncm_ignore_list); +} +#endif -- 2.25.1