From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Authentication-Results: smtp.codeaurora.org; dkim=fail reason="key not found in DNS" (0-bit key) header.d=micronovasrl.com header.i=@micronovasrl.com header.b="d1TBjwfm" DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 1C1C960763 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=micronovasrl.com Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753056AbeFFTQw (ORCPT + 25 others); Wed, 6 Jun 2018 15:16:52 -0400 Received: from mail.micronovasrl.com ([212.103.203.10]:45626 "EHLO mail.micronovasrl.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752042AbeFFTQu (ORCPT ); Wed, 6 Jun 2018 15:16:50 -0400 Authentication-Results: mail.micronovasrl.com (amavisd-new); dkim=pass reason="pass (just generated, assumed good)" header.d=micronovasrl.com Subject: Re: [PATCH 1/4] serial: 8250_dw: add em485 support To: Andy Shevchenko Cc: "Matwey V. Kornilov" , Andy Shevchenko , Greg Kroah-Hartman , Jiri Slaby , Ed Blake , Joshua Scott , "open list:SERIAL DRIVERS" , open list References: <20180606095156.72628-1-giulio.benetti@micronovasrl.com> <20180606095156.72628-4-giulio.benetti@micronovasrl.com> From: Giulio Benetti Message-ID: <9d8bdd5b-842f-8943-a186-a99f31d71a2a@micronovasrl.com> Date: Wed, 6 Jun 2018 21:16:37 +0200 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.8.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: it Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Il 06/06/2018 18:51, Andy Shevchenko ha scritto: > On Wed, Jun 6, 2018 at 12:51 PM, Giulio Benetti > wrote: >> Need to use rs485 transceiver so let's use existing em485 485 emulation >> layer on top of 8250. >> >> Add rs485_config callback to port. > > Besides the fact the series lacks of cover letter, I think it should Sorry for that, next patchsets will have cover-letters. > be postponed until we get a clear understanding how RS485 is supposed > to be initialized and what exact problems you are trying to address. > >> >> Signed-off-by: Giulio Benetti >> --- >> drivers/tty/serial/8250/8250_dw.c | 31 +++++++++++++++++++++++++++++++ >> 1 file changed, 31 insertions(+) >> >> diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c >> index 6fcdb90f616a..45366e6e5411 100644 >> --- a/drivers/tty/serial/8250/8250_dw.c >> +++ b/drivers/tty/serial/8250/8250_dw.c >> @@ -314,6 +314,36 @@ static void dw8250_set_ldisc(struct uart_port *p, struct ktermios *termios) >> serial8250_do_set_ldisc(p, termios); >> } >> >> +static int dw8250_rs485_config(struct uart_port *p, >> + struct serial_rs485 *rs485) >> +{ >> + struct uart_8250_port *up = up_to_u8250p(p); >> + >> + /* Clamp the delays to [0, 100ms] */ >> + rs485->delay_rts_before_send = min(rs485->delay_rts_before_send, 100U); >> + rs485->delay_rts_after_send = min(rs485->delay_rts_after_send, 100U); >> + >> + p->rs485 = *rs485; >> + >> + /* >> + * Both serial8250_em485_init and serial8250_em485_destroy >> + * are idempotent >> + */ >> + if (rs485->flags & SER_RS485_ENABLED) { >> + int ret = serial8250_em485_init(up); >> + >> + if (ret) { >> + rs485->flags &= ~SER_RS485_ENABLED; >> + p->rs485.flags &= ~SER_RS485_ENABLED; >> + } >> + return ret; >> + } >> + >> + serial8250_em485_destroy(up); >> + >> + return 0; >> +} >> + >> /* >> * dw8250_fallback_dma_filter will prevent the UART from getting just any free >> * channel on platforms that have DMA engines, but don't have any channels >> @@ -449,6 +479,7 @@ static int dw8250_probe(struct platform_device *pdev) >> p->serial_out = dw8250_serial_out; >> p->set_ldisc = dw8250_set_ldisc; >> p->set_termios = dw8250_set_termios; >> + p->rs485_config = dw8250_rs485_config; >> >> p->membase = devm_ioremap(dev, regs->start, resource_size(regs)); >> if (!p->membase) >> -- >> 2.17.1 >> > > > -- Giulio Benetti CTO MICRONOVA SRL Sede: Via A. Niedda 3 - 35010 Vigonza (PD) Tel. 049/8931563 - Fax 049/8931346 Cod.Fiscale - P.IVA 02663420285 Capitale Sociale € 26.000 i.v. Iscritta al Reg. Imprese di Padova N. 02663420285 Numero R.E.A. 258642