Re: [PATCH] usb: dwc3: Fix debugfs creation flow

[Jack Pham <jackp@codeaurora.org>]

Hi Minas,

On Wed, Jun 16, 2021 at 10:56:02PM -0700, Minas Harutyunyan wrote:
> Creation EP's debugfs called earlier than debugfs folder for dwc3
> device created. As result EP's debugfs are created in '/sys/kernel/debug'
> instead of '/sys/kernel/debug/usb/dwc3.1.auto'.

Interesting, I didn't encounter this in my testing. Oh but in our case
we have dr_mode as USB_DR_MODE_OTG, so when dwc3_core_init_mode() calls
dwc3_drd_init() the gadget_init() is done from a worker, and meanwhile
dwc3_debugfs_init() would have already had a chance to create the root
folder before that.

I'm assuming you're seeing this with dr_mode == USB_DR_MODE_PERIPHERAL?
Then in that case dwc3_core_init_mode() synchronously calls
dwc3_gadget_init() before the debugfs_init.

> Moved dwc3_debugfs_init() function call before calling
> dwc3_core_init_mode() to allow create dwc3 debugfs parent before
> creating EP's debugfs's.
> 
> Fixes: 8562d5bfc0fc ("USB: dwc3: remove debugfs root dentry storage")

Isn't it fixing 8d396bb0a5b6 ("usb: dwc3: debugfs: Add and remove
endpoint dirs dynamically")?  More fallout from my change I guess :-/.

Anyway it looks good to me, thanks!

Reviewed-by: Jack Pham <jackp@codeaurora.org>

> Signed-off-by: Minas Harutyunyan <hminas@synopsys.com>
> ---
>  drivers/usb/dwc3/core.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> index e0a8e796c158..ba74ad7f6995 100644
> --- a/drivers/usb/dwc3/core.c
> +++ b/drivers/usb/dwc3/core.c
> @@ -1620,17 +1620,18 @@ static int dwc3_probe(struct platform_device *pdev)
>  	}
>  
>  	dwc3_check_params(dwc);
> +	dwc3_debugfs_init(dwc);
>  
>  	ret = dwc3_core_init_mode(dwc);
>  	if (ret)
>  		goto err5;
>  
> -	dwc3_debugfs_init(dwc);
>  	pm_runtime_put(dev);
>  
>  	return 0;
>  
>  err5:
> +	dwc3_debugfs_exit(dwc);
>  	dwc3_event_buffers_cleanup(dwc);
>  
>  	usb_phy_shutdown(dwc->usb2_phy);
> 
> base-commit: 1da8116eb0c5dfc05cfb89896239badb18c4daf3
> -- 
> 2.11.0
>