From mboxrd@z Thu Jan 1 00:00:00 1970 From: Corey Minyard Subject: [PATCH 4/8] serial: Add circular buffer helpers Date: Thu, 26 Apr 2007 13:50:22 -0500 Message-ID: <20070426185022.GD25521@localdomain> Reply-To: minyard@acm.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mta13.mail.adelphia.net ([68.168.78.44]:48276 "EHLO mta13.adelphia.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1031442AbXDZSuZ (ORCPT ); Thu, 26 Apr 2007 14:50:25 -0400 Content-Disposition: inline Sender: linux-serial-owner@vger.kernel.org List-Id: linux-serial@vger.kernel.org To: Alan Cox , linux-serial@vger.kernel.org Subject: serial: Add circular buffer helpers Add some helper macros to neaten things up a little in the serial drivers. Signed-off-by: Corey Minyard drivers/serial/8250.c | 7 ++++--- include/linux/serial_core.h | 2 ++ 2 files changed, 6 insertions(+), 3 deletions(-) Index: linux-2.6.21/drivers/serial/8250.c =================================================================== --- linux-2.6.21.orig/drivers/serial/8250.c +++ linux-2.6.21/drivers/serial/8250.c @@ -1265,7 +1265,7 @@ static int receive_chars(struct uart_825 static int transmit_chars(struct uart_8250_port *up) { - struct circ_buf *xmit = &up->port.info->xmit; + struct circ_buf *xmit = uart_get_circ_buf(&up->port); int count; int xmit_ready = 0; @@ -1287,7 +1287,7 @@ static int transmit_chars(struct uart_82 count = up->tx_loadsz; do { serial_out(up, UART_TX, xmit->buf[xmit->tail]); - xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); + xmit->tail = uart_wrap_circ_buf(xmit->tail + 1); up->port.icount.tx++; if (uart_circ_empty(xmit)) break; @@ -1507,6 +1507,7 @@ static void serial8250_timeout(unsigned static void serial8250_backup_timeout(unsigned long data) { struct uart_8250_port *up = (struct uart_8250_port *)data; + struct circ_buf *xmit = uart_get_circ_buf(&up->port); unsigned int iir, ier = 0; /* @@ -1527,7 +1528,7 @@ static void serial8250_backup_timeout(un * ia64 and parisc boxes. */ if ((iir & UART_IIR_NO_INT) && (up->ier & UART_IER_THRI) && - (!uart_circ_empty(&up->port.info->xmit) || up->port.x_char) && + (!uart_circ_empty(xmit) || up->port.x_char) && (serial_in(up, UART_LSR) & UART_LSR_THRE)) { iir &= ~(UART_IIR_ID | UART_IIR_NO_INT); iir |= UART_IIR_THRI; Index: linux-2.6.21/include/linux/serial_core.h =================================================================== --- linux-2.6.21.orig/include/linux/serial_core.h +++ linux-2.6.21/include/linux/serial_core.h @@ -398,6 +398,8 @@ int uart_resume_port(struct uart_driver #define uart_circ_empty(circ) ((circ)->head == (circ)->tail) #define uart_circ_clear(circ) ((circ)->head = (circ)->tail = 0) +#define uart_get_circ_buf(port) (&(port)->info->xmit) +#define uart_wrap_circ_buf(val) ((val) & (UART_XMIT_SIZE - 1)) #define uart_circ_chars_pending(circ) \ (CIRC_CNT((circ)->head, (circ)->tail, UART_XMIT_SIZE))