From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753507AbbKGOVA (ORCPT ); Sat, 7 Nov 2015 09:21:00 -0500 Received: from mail-ig0-f177.google.com ([209.85.213.177]:35373 "EHLO mail-ig0-f177.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752541AbbKGOU7 (ORCPT ); Sat, 7 Nov 2015 09:20:59 -0500 Subject: Re: [PATCH v2 2/3] tty: Implement default fallback serial8250_rs485_config To: "Matwey V. Kornilov" 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> Cc: Greg KH , jslaby@suse.com, linux-serial@vger.kernel.org, linux-kernel From: Peter Hurley Message-ID: <563E08C6.7000505@hurleysoftware.com> Date: Sat, 7 Nov 2015 09:20:54 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.3.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/07/2015 08:51 AM, Matwey V. Kornilov wrote: > 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? Whoops, sorry! :/ For now, assign the default 8250 port function in serial8250_set_defaults(). Regards, Peter Hurley >> 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; >>> >> > > >