Re: [PATCH v3 1/2] usb: gadget: goku_udc: move debug output to debugfs
From: Greg Kroah-Hartman
Date: Wed Aug 26 2026 - 06:29:45 EST
On Wed, Aug 26, 2026 at 05:15:06PM +0800, Cheng Lingfei wrote:
> goku_udc exposes diagnostic state through /proc/driver/udc. The single
> global proc entry collides when more than one controller is probed and
> triggers a proc registration warning.
>
> The data is intended only for debugging and is not a userspace ABI. Move it
> under the USB debugfs root and use the PCI device name for a per-device
> directory. Create the file only after the UDC has been registered.
>
> Suggested-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> Link: https://lore.kernel.org/2026082616-glue-atlas-0cfd@gregkh
> Assisted-by: Codex:gpt-5.6
> Signed-off-by: Cheng Lingfei <chenglingfei@xxxxxxxxxxx>
> ---
> drivers/usb/gadget/udc/goku_udc.c | 47 +++++++++++++++++++++++++++------------
> drivers/usb/gadget/udc/goku_udc.h | 5 ++++-
> 2 files changed, 37 insertions(+), 15 deletions(-)
>
> diff --git a/drivers/usb/gadget/udc/goku_udc.c b/drivers/usb/gadget/udc/goku_udc.c
> index ac2a984c2f87..5ad8633f522b 100644
> --- a/drivers/usb/gadget/udc/goku_udc.c
> +++ b/drivers/usb/gadget/udc/goku_udc.c
> @@ -20,6 +20,7 @@
> // #define VERBOSE /* extra debug messages (success too) */
> // #define USB_TRACE /* packet-level success messages */
>
> +#include <linux/debugfs.h>
> #include <linux/kernel.h>
> #include <linux/module.h>
> #include <linux/pci.h>
> @@ -30,9 +31,9 @@
> #include <linux/timer.h>
> #include <linux/list.h>
> #include <linux/interrupt.h>
> -#include <linux/proc_fs.h>
> #include <linux/seq_file.h>
> #include <linux/device.h>
> +#include <linux/usb.h>
> #include <linux/usb/ch9.h>
> #include <linux/usb/gadget.h>
> #include <linux/prefetch.h>
> @@ -1050,9 +1051,7 @@ static inline const char *dmastr(void)
> return "(dma IN)";
> }
>
> -#ifdef CONFIG_USB_GADGET_DEBUG_FILES
> -
> -static const char proc_node_name [] = "driver/udc";
> +#ifdef CONFIG_USB_GADGET_DEBUG_FS
Why do you need this config option check anymore?