diff mbox series

[3/4] usb-serial: Increase receive buffer to 496

Message ID 20200312125524.7812-4-jandryuk@gmail.com (mailing list archive)
State New, archived
Headers show
Series usb-serial: xHCI and timeout fixes | expand

Commit Message

Jason Andryuk March 12, 2020, 12:55 p.m. UTC
A FTDI USB adapter on an xHCI controller can send 512 byte USB packets.
These are 8 * ( 2 bytes header + 62 bytes data).  A 384 byte receive
buffer is insufficient to fill a 512 byte packet, so bump the receive
size to 496 ( 512 - 2 * 8 ).

Signed-off-by: Jason Andryuk <jandryuk@gmail.com>
---
 hw/usb/dev-serial.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Samuel Thibault March 14, 2020, 9:40 p.m. UTC | #1
Jason Andryuk, le jeu. 12 mars 2020 08:55:22 -0400, a ecrit:
> A FTDI USB adapter on an xHCI controller can send 512 byte USB packets.
> These are 8 * ( 2 bytes header + 62 bytes data).  A 384 byte receive
> buffer is insufficient to fill a 512 byte packet, so bump the receive
> size to 496 ( 512 - 2 * 8 ).
> 
> Signed-off-by: Jason Andryuk <jandryuk@gmail.com>

Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org>

> ---
>  hw/usb/dev-serial.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/hw/usb/dev-serial.c b/hw/usb/dev-serial.c
> index 96b6c34202..ef33bcd127 100644
> --- a/hw/usb/dev-serial.c
> +++ b/hw/usb/dev-serial.c
> @@ -29,7 +29,7 @@ do { printf("usb-serial: " fmt , ## __VA_ARGS__); } while (0)
>  #define DPRINTF(fmt, ...) do {} while(0)
>  #endif
>  
> -#define RECV_BUF 384
> +#define RECV_BUF (512 - (2 * 8))
>  
>  /* Commands */
>  #define FTDI_RESET		0
> -- 
> 2.24.1
>
diff mbox series

Patch

diff --git a/hw/usb/dev-serial.c b/hw/usb/dev-serial.c
index 96b6c34202..ef33bcd127 100644
--- a/hw/usb/dev-serial.c
+++ b/hw/usb/dev-serial.c
@@ -29,7 +29,7 @@  do { printf("usb-serial: " fmt , ## __VA_ARGS__); } while (0)
 #define DPRINTF(fmt, ...) do {} while(0)
 #endif
 
-#define RECV_BUF 384
+#define RECV_BUF (512 - (2 * 8))
 
 /* Commands */
 #define FTDI_RESET		0