Re: [PATCH 5/5] USB: serial: f81232: fix bulk_in/out size

[Johan Hovold]

On Mon, Jan 22, 2018 at 03:58:47PM +0800, Ji-Ze Hong (Peter Hong) wrote:
> Fix Fintek F81232 bulk_in/out size to 64/16 according to the spec.
> http://html.alldatasheet.com/html-pdf/406315/FINTEK/F81232/1762/8/F81232.html
> 
> Signed-off-by: Ji-Ze Hong (Peter Hong) <hpeter+linux_kernel@xxxxxxxxx>
> ---
>  drivers/usb/serial/f81232.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/drivers/usb/serial/f81232.c b/drivers/usb/serial/f81232.c
> index a054f69446fd..f3ee537d643c 100644
> --- a/drivers/usb/serial/f81232.c
> +++ b/drivers/usb/serial/f81232.c
> @@ -769,8 +769,7 @@ static struct usb_serial_driver f81232_device = {
>  	},
>  	.id_table =		id_table,
>  	.num_ports =		1,
> -	.bulk_in_size =		256,
> -	.bulk_out_size =	256,
> +	.bulk_out_size =	16,

These fields control the URB buffer sizes and defaults to the corresponding
endpoint max-packet size, which would be 16 for all endpoints according
to the datasheet above.

So it seems you should really be setting bulk_in_size to 64 here (and
possibly leave bulk_out_size unset) as that would appear to match your
device buffer sizes.

Johan