Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933864AbbHJKQJ (ORCPT ); Mon, 10 Aug 2015 06:16:09 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:43872 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933803AbbHJKPv (ORCPT ); Mon, 10 Aug 2015 06:15:51 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Nicolas Ferre" , "Greg Kroah-Hartman" , "Sami =?UTF-8?Q?Pietik=C3=A4inen?=" Date: Mon, 10 Aug 2015 12:12:30 +0200 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 010/110] tty/serial: at91: RS485 mode: 0 is valid for delay_rts_after_send In-Reply-To: X-SA-Exim-Connect-IP: 2.173.94.72 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2614 Lines: 64 3.2.71-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Nicolas Ferre commit 8687634b7908c42eb700e0469e110e02833611d1 upstream. In RS485 mode, we may want to set the delay_rts_after_send value to 0. In the datasheet, the 0 value is said to "disable" the Transmitter Timeguard but this is exactly the expected behavior if we want no delay... Moreover, if the value was set to non-zero value by device-tree or earlier ioctl command, it was impossible to change it back to zero. Reported-by: Sami Pietikäinen Signed-off-by: Nicolas Ferre Signed-off-by: Greg Kroah-Hartman [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings --- drivers/tty/serial/atmel_serial.c | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) --- a/drivers/tty/serial/atmel_serial.c +++ b/drivers/tty/serial/atmel_serial.c @@ -229,8 +229,7 @@ void atmel_config_rs485(struct uart_port if (rs485conf->flags & SER_RS485_ENABLED) { dev_dbg(port->dev, "Setting UART to RS485\n"); atmel_port->tx_done_mask = ATMEL_US_TXEMPTY; - if ((rs485conf->delay_rts_after_send) > 0) - UART_PUT_TTGR(port, rs485conf->delay_rts_after_send); + UART_PUT_TTGR(port, rs485conf->delay_rts_after_send); mode |= ATMEL_US_USMODE_RS485; } else { dev_dbg(port->dev, "Setting UART to RS232\n"); @@ -305,9 +304,7 @@ static void atmel_set_mctrl(struct uart_ if (atmel_port->rs485.flags & SER_RS485_ENABLED) { dev_dbg(port->dev, "Setting UART to RS485\n"); - if ((atmel_port->rs485.delay_rts_after_send) > 0) - UART_PUT_TTGR(port, - atmel_port->rs485.delay_rts_after_send); + UART_PUT_TTGR(port, atmel_port->rs485.delay_rts_after_send); mode |= ATMEL_US_USMODE_RS485; } else { dev_dbg(port->dev, "Setting UART to RS232\n"); @@ -1229,9 +1226,7 @@ static void atmel_set_termios(struct uar if (atmel_port->rs485.flags & SER_RS485_ENABLED) { dev_dbg(port->dev, "Setting UART to RS485\n"); - if ((atmel_port->rs485.delay_rts_after_send) > 0) - UART_PUT_TTGR(port, - atmel_port->rs485.delay_rts_after_send); + UART_PUT_TTGR(port, atmel_port->rs485.delay_rts_after_send); mode |= ATMEL_US_USMODE_RS485; } else { dev_dbg(port->dev, "Setting UART to RS232\n"); -- 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/