From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753458AbbKGNvk (ORCPT ); Sat, 7 Nov 2015 08:51:40 -0500 Received: from mail-wi0-f177.google.com ([209.85.212.177]:36984 "EHLO mail-wi0-f177.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753214AbbKGNvi (ORCPT ); Sat, 7 Nov 2015 08:51:38 -0500 MIME-Version: 1.0 In-Reply-To: <563DEE8F.4050401@hurleysoftware.com> References: <1446890976-1817-1-git-send-email-matwey@sai.msu.ru> <1446890976-1817-2-git-send-email-matwey@sai.msu.ru> <563DEE8F.4050401@hurleysoftware.com> From: "Matwey V. Kornilov" Date: Sat, 7 Nov 2015 16:51:16 +0300 X-Google-Sender-Auth: C9bjbcGD5LLprRqECAd2zIP3jwo Message-ID: Subject: Re: [PATCH v2 2/3] tty: Implement default fallback serial8250_rs485_config To: Peter Hurley Cc: Greg KH , jslaby@suse.com, linux-serial@vger.kernel.org, linux-kernel Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2015-11-07 15:29 GMT+03:00 Peter Hurley : > Hi Matwey, > > On 11/07/2015 05:09 AM, Matwey V. Kornilov wrote: >> When 8250 driver doesn't have its own hardware RS485 support and doesn't >> want to override rs485_config callback, then default >> serial8250_rs485_config is used. It just stores supplied by user-space >> config. >> >> Signed-off-by: Matwey V. Kornilov >> --- >> drivers/tty/serial/8250/8250_core.c | 10 ++++++++++ >> 1 file changed, 10 insertions(+) >> >> diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c >> index 3912646..8f292da 100644 >> --- a/drivers/tty/serial/8250/8250_core.c >> +++ b/drivers/tty/serial/8250/8250_core.c >> @@ -395,6 +395,12 @@ static void serial8250_release_rsa_resource(struct uart_8250_port *up) >> } >> } >> #endif >> +static int serial8250_rs485_config(struct uart_port *port, >> + struct serial_rs485 *rs485) >> +{ >> + port->rs485 = *rs485; >> + return 0; >> +} >> >> static const struct uart_ops *base_ops; >> static struct uart_ops univ8250_port_ops; >> @@ -990,6 +996,10 @@ int serial8250_register_8250_port(struct uart_8250_port *up) >> uart->port.rs485 = up->port.rs485; >> uart->dma = up->dma; >> >> + /* Use software RS485 support when hardware one is not available */ >> + if (!(uart->capabilities & UART_CAP_HW485) && !uart->port.rs485_config) >> + uart->port.rs485_config = serial8250_rs485_config; > > To setup a default 8250 port function, > 1. define the default 8250 port function in 8250/8250_port.c > 2. add the port function to the dispatch table (serial8250_pops) rs485_config is not a member of struct uart_ops, should I add it there? > 3. add a test for 8250 sub-driver override in serial8250_register_8250_port() > Eg., > > if (up->port.rs485_config) > uart->port.rs485_config = up->port.rs485_config; > > Regards, > Peter Hurley > >> /* Take tx_loadsz from fifosize if it wasn't set separately */ >> if (uart->port.fifosize && !uart->tx_loadsz) >> uart->tx_loadsz = uart->port.fifosize; >> > -- With best regards, Matwey V. Kornilov. Sternberg Astronomical Institute, Lomonosov Moscow State University, Russia 119991, Moscow, Universitetsky pr-k 13, +7 (495) 9392382