From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5AC6DC433EF for ; Fri, 24 Dec 2021 09:21:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1352211AbhLXJVY (ORCPT ); Fri, 24 Dec 2021 04:21:24 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41304 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1352184AbhLXJVW (ORCPT ); Fri, 24 Dec 2021 04:21:22 -0500 Received: from mail-pg1-x52b.google.com (mail-pg1-x52b.google.com [IPv6:2607:f8b0:4864:20::52b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AF156C061401; Fri, 24 Dec 2021 01:21:21 -0800 (PST) Received: by mail-pg1-x52b.google.com with SMTP id r138so7179075pgr.13; Fri, 24 Dec 2021 01:21:21 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=jPTx7nBzf3LGvXSQtblaPA6rluMMl4EIwS4QSTaWNdQ=; b=S/G2s7v9BwstG5jCKU8gxj0HYm4JOcx8yewb+48mW6QSQyTq3Rh92pqutu4azFNwBJ 7XTkFCnna2RIbPUXHDEkE0OqzmPRr5Ybgd2Iceg0pRORmM2cLEOveHQSaj0i2L6VBiex P8HobsWgdlfjBZAqJa/nWOcZqx3B0rvkGguJ75Vq5UWipG0t7gwzrs5d3GN2wo6JLaip XqdbgTVunkrxgtVu8XiOzXOH3ClTsPpfsw2J8bNmSIGCoCEzwtifpTpwpyZp38ORut/Z 9yi0zQbqllyVJvcFNrArEFykcUZcUMDr63+izcagTYusBFQD+iSaWcvcGNB1ix4Pr0p+ i/lQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=jPTx7nBzf3LGvXSQtblaPA6rluMMl4EIwS4QSTaWNdQ=; b=xz3qCi2NqXIjCxkkB+9fcJSJEU36AcufEgA9CDncQi2D/UyHtEDx9SHu1CNQT7nIt9 eSB+L7j1DOBMw0AwjTqu0/xDwJNEMkMs2+Sg5hhi8SBYsvi52XKUwsmRhBbsJRDhZP+1 MUvVkfgj/B1dgMyDpv+xt42M8Se6tYGnyatME5qyn3qw/GI4JfrGyp9kEPUJczm5hAXq vZly1xaF4XhW143dHqW7JMJsb0yUtKMp6ldKFbZ2MRTnrekX4YaR9Z7wYdxmVCYPe8ae dj+yxJo5TIoZssnmQR/FVQWuYDNrIaccVLXYqFsJCEOKuIEUaYI5hgn+SjQXwvAkNJs7 zEDg== X-Gm-Message-State: AOAM532Hv6sWd2H+CjCIN2klMJJQZrCZ2Ob5+tbasuHL6prldS9gwhMt B+AVOrK0VsIDmdlO9dNjC8/Yp3gC+oIG3xqt6QuHPpLIdWH8cQ== X-Google-Smtp-Source: ABdhPJz83YQbB1p+N/DrriVlSCxR13zuFw4QgI5rHqcDrrdrRy6QSkXzM16JVop4Dp8A8hg+yfZbRCWAn1A0ubnKKQs= X-Received: by 2002:a05:6a00:16d3:b0:4ba:4aee:2e34 with SMTP id l19-20020a056a0016d300b004ba4aee2e34mr6048662pfc.82.1640337681216; Fri, 24 Dec 2021 01:21:21 -0800 (PST) MIME-Version: 1.0 References: <1639379407-28607-1-git-send-email-hammer.hsieh@sunplus.com> <1639379407-28607-3-git-send-email-hammer.hsieh@sunplus.com> In-Reply-To: From: hammer hsieh Date: Fri, 24 Dec 2021 17:21:27 +0800 Message-ID: Subject: Re: [PATCH v5 2/2] serial:sunplus-uart:Add Sunplus SoC UART Driver To: Greg KH Cc: robh+dt@kernel.org, linux-serial@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, jirislaby@kernel.org, p.zabel@pengutronix.de, wells.lu@sunplus.com, Hammer Hsieh Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, Greg KH: I am still not really understand why you said the driver looks like 8250. SP7021 SoC have our own register define. That's why we submit a new serial driver. Refer to: https://sunplus.atlassian.net/wiki/spaces/doc/pages/1873412290/13.+Universa= l+Asynchronous+Receiver+Transmitter+UART Regards, Hammer Hsieh hammer hsieh =E6=96=BC 2021=E5=B9=B412=E6=9C=8824= =E6=97=A5 =E9=80=B1=E4=BA=94 =E4=B8=8B=E5=8D=885:05=E5=AF=AB=E9=81=93=EF=BC= =9A > > Hi, Greg KH: > > 8250 driver means create driver in drivers/tty/8250/ ? > and current I create driver in drivers/tty/serial/ not correct ? > > Regards, > Hammer Hsieh > > Greg KH =E6=96=BC 2021=E5=B9=B412=E6=9C=8824= =E6=97=A5 =E9=80=B1=E4=BA=94 =E4=B8=8B=E5=8D=884:59=E5=AF=AB=E9=81=93=EF=BC= =9A > > > > On Fri, Dec 24, 2021 at 03:16:55PM +0800, hammer hsieh wrote: > > > Hi, Greg KH : > > > > > > In patch v1 coding quite mess, it is almost 2000 LOCs. > > > For down size code under 1000 LOCs, I decide to drop DMA function cod= e > > > after patch v3. > > > I think that's the biggest difference compared with 8250. > > > Without DMA function, like you said it looks like 8250 variant. > > > I think I should put DMA function back in next submit. > > > > The 8250 driver handles DMA just fine today, why is your chip doing it > > differently? Are you sure it is a different chip? Who created a new > > uart chip these days? > > > > > Another question for why I need PORT_SLUNPLUS ? > > > I just check many other uart driver, almost all driver define their > > > own PORT number. > > > Actually, I didn't know about it. > > > Maybe some device like bluetooth(use uart port) need autoconfig. > > > Then it will call ioctl with TIOCSERCONFIG. > > > I don't have tool for calling type/config/request/release/verify. > > > > If you do not need it, and you can not test for it, please do not add > > it. > > > > thanks, > > > > greg k-h