Re: [PATCH 2/5] firmware_loader: add support to handle FW_UPLOAD_ERR_SKIP

[Russ Weight]

On Tue, Nov 19, 2024 at 11:33:51PM +0100, Marco Felsch wrote:
> It's no error if a driver indicates that the firmware is already
> up-to-date and the update can be skipped.
> 
> Signed-off-by: Marco Felsch <m.felsch@xxxxxxxxxxxxxx>
> ---
>  drivers/base/firmware_loader/sysfs_upload.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/base/firmware_loader/sysfs_upload.c b/drivers/base/firmware_loader/sysfs_upload.c
> index b3cbe5b156e3..44f3d8fa5e64 100644
> --- a/drivers/base/firmware_loader/sysfs_upload.c
> +++ b/drivers/base/firmware_loader/sysfs_upload.c
> @@ -174,6 +174,10 @@ static void fw_upload_main(struct work_struct *work)
>  	fw_upload_update_progress(fwlp, FW_UPLOAD_PROG_PREPARING);
>  	ret = fwlp->ops->prepare(fwl, fwlp->data, fwlp->remaining_size);
>  	if (ret != FW_UPLOAD_ERR_NONE) {
> +		if (ret == FW_UPLOAD_ERR_SKIP) {
> +			dev_info(fw_dev, "firmware already up-to-date, skip update\n");
> +			ret = FW_UPLOAD_ERR_NONE;
> +		}

If you change the error-code from FW_UPLOAD_ERR_SKIP to
FW_UPLOAD_ERR_NONE, then the "skip" string provided in the previous
patch will never be seen. There are currently no other instances where
an error code requires special-case modifications to the fw_upload
code and I don't think it is necessary to add it here.

The dev_info() message above can be provided by the device driver
that is using this API.

I think you can either:

(1) allow "skip" to be treated as an error. The update didn't happen...

-or-

(2) The prepare function could detect the situation and set
    a flag in the same device driver. Your write function could
    set *written to the full data size and return without writing
    anything. Your poll_complete handler could also return
    FW_UPLOAD_ERR_NONE. Then you don't need to add FW_UPLOAD_ERR_SKIP
    at all. You would get the info message from the device driver
    and fw_upload would exit without an error.

Thanks,
- Russ

>  		fw_upload_set_error(fwlp, ret);
>  		goto putdev_exit;
>  	}
> 
> -- 
> 2.39.5
>