Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751552AbbBPTlS (ORCPT ); Mon, 16 Feb 2015 14:41:18 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:50584 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751276AbbBPTlQ (ORCPT ); Mon, 16 Feb 2015 14:41:16 -0500 Date: Mon, 16 Feb 2015 11:41:15 -0800 From: Greg KH To: Peter Hung Cc: johan@kernel.org, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, tom_tsai@fintek.com.tw, peter_hong@fintek.com.tw, Peter Hung Subject: Re: [PATCH V6 03/10] USB: f81232: implement RX bulk-in ep Message-ID: <20150216194115.GB9296@kroah.com> References: <1424073482-18164-1-git-send-email-hpeter+linux_kernel@gmail.com> <1424073482-18164-4-git-send-email-hpeter+linux_kernel@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1424073482-18164-4-git-send-email-hpeter+linux_kernel@gmail.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2799 Lines: 76 On Mon, Feb 16, 2015 at 03:57:55PM +0800, Peter Hung wrote: > The F81232 bulk-in is RX data + LSR channel, data format is > [LSR+Data][LSR+Data]..... , We had reimplemented in this patch. > > Signed-off-by: Peter Hung > --- > drivers/usb/serial/f81232.c | 68 +++++++++++++++++++++++---------------------- > 1 file changed, 35 insertions(+), 33 deletions(-) > > diff --git a/drivers/usb/serial/f81232.c b/drivers/usb/serial/f81232.c > index ec4609d..9ea498a 100644 > --- a/drivers/usb/serial/f81232.c > +++ b/drivers/usb/serial/f81232.c > @@ -185,44 +185,46 @@ exit: > 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; > + char tty_flag; > 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); > - > - if (!urb->actual_length) > + if (urb->actual_length < 2) > return; > > - /* break takes precedence over parity, */ > - /* which takes precedence over framing errors */ > - if (line_status & UART_BREAK_ERROR) > - tty_flag = TTY_BREAK; > - else if (line_status & UART_PARITY_ERROR) > - tty_flag = TTY_PARITY; > - else if (line_status & UART_FRAME_ERROR) > - tty_flag = TTY_FRAME; > - dev_dbg(&port->dev, "%s - tty_flag = %d\n", __func__, tty_flag); > - > - /* overrun is special, not associated with a char */ > - if (line_status & UART_OVERRUN_ERROR) > - tty_insert_flip_char(&port->port, 0, TTY_OVERRUN); > - > - if (port->port.console && port->sysrq) { > - for (i = 0; i < urb->actual_length; ++i) > - if (!usb_serial_handle_sysrq_char(port, data[i])) > - tty_insert_flip_char(&port->port, data[i], > - tty_flag); > - } else { > - tty_insert_flip_string_fixed_flag(&port->port, data, tty_flag, > - urb->actual_length); > + /* bulk-in data: [LSR(1Byte)+DATA(1Byte)][LSR(1Byte)+DATA(1Byte)]... */ > + > + for (i = 0 ; i < urb->actual_length ; i += 2) { > + tty_flag = TTY_NORMAL; > + > + if (unlikely(data[i+0] & UART_LSR_BRK_ERROR_BITS)) { Never use unlikely() unless you can prove that it actually matters if you use it. Hint, it's almost impossible to prove, so don't use it, the compiler and processor look-ahead is almost smarter than we are. thanks, greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/