Re: [PATCH V8 02/10] USB: f81232: implement RX bulk-in EP

From: Johan Hovold
Date: Sat Mar 14 2015 - 07:49:14 EST


On Thu, Feb 26, 2015 at 06:02:08PM +0800, Peter Hung wrote:
> The F81232 bulk-in is RX data + LSR channel, data format is
> [LSR+Data][LSR+Data]..... , We had implemented in f81232_process_read_urb().
>
> Signed-off-by: Peter Hung <hpeter+linux_kernel@xxxxxxxxx>

> static void f81232_process_read_urb(struct urb *urb)
> {
> struct usb_serial_port *port = urb->context;
> - struct f81232_private *priv = usb_get_serial_port_data(port);
> unsigned char *data = urb->transfer_buffer;
> - char tty_flag = TTY_NORMAL;
> - unsigned long flags;
> - u8 line_status;
> - int i;
> -
> - /* update line status */
> - spin_lock_irqsave(&priv->lock, flags);
> - line_status = priv->modem_status;
> - priv->modem_status &= ~UART_STATE_TRANSIENT_MASK;
> - spin_unlock_irqrestore(&priv->lock, flags);
> + char tty_flag;
> + unsigned int i;
> + u8 lsr;
>
> - if (!urb->actual_length)
> + if ((urb->actual_length < 2) || (urb->actual_length % 2))
> return;

Not parsing short data (e.g. not divisible by 2) is OK I guess. You
could also just discard the last odd byte, but that's up to you.

Either way, I think you should add a dev_warn here rather than just
silently drop it.

Johan
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/