[PATCH] net/can/gs_usb: increase max interface to 255

From: Celeste Liu

Date: Mon Sep 29 2025 - 07:10:19 EST


This issue was found by Runcheng Lu when develop HSCanT USB to CAN FD
converter[1]. The original developers may have only 3 intefaces device to
test so they write 3 here and wait for future change.

During the HSCanT development, we actually used 4 interfaces, so the
limitation of 3 is not enough now. But just increase one is not
future-proofed. Since the channel type in gs_host_frame is u8, use 255
as max interface number should be safe.

[1]: https://github.com/cherry-embedded/HSCanT-hardware

Reported-by: Runcheng Lu <runcheng.lu@xxxxxxxxxxx>
Signed-off-by: Celeste Liu <uwu@xxxxxxxxxxxxxxxxx>
---
drivers/net/can/usb/gs_usb.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/can/usb/gs_usb.c b/drivers/net/can/usb/gs_usb.c
index c9482d6e947b0c7b033dc4f0c35f5b111e1bfd92..35fc257c19e57c1f33e03e7c86ea908d22400254 100644
--- a/drivers/net/can/usb/gs_usb.c
+++ b/drivers/net/can/usb/gs_usb.c
@@ -290,9 +290,9 @@ struct gs_host_frame {
#define GS_NAPI_WEIGHT 32

/* Maximum number of interfaces the driver supports per device.
- * Current hardware only supports 3 interfaces. The future may vary.
+ * The channel number type of gs_host_frame is u8, so max interfaces can be 255.
*/
-#define GS_MAX_INTF 3
+#define GS_MAX_INTF 255

struct gs_tx_context {
struct gs_can *dev;

---
base-commit: e5f0a698b34ed76002dc5cff3804a61c80233a7a
change-id: 20250929-gs-usb-max-if-a304c83243e5

Best regards,
--
Celeste Liu <uwu@xxxxxxxxxxxxxxxxx>