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 X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5D1B1C43603 for ; Sat, 14 Dec 2019 23:07:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 37CEB20724 for ; Sat, 14 Dec 2019 23:07:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726820AbfLNXH5 (ORCPT ); Sat, 14 Dec 2019 18:07:57 -0500 Received: from gloria.sntech.de ([185.11.138.130]:43282 "EHLO gloria.sntech.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726803AbfLNXH5 (ORCPT ); Sat, 14 Dec 2019 18:07:57 -0500 Received: from ip5f5a6266.dynamic.kabel-deutschland.de ([95.90.98.102] helo=diego.localnet) by gloria.sntech.de with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1igGVq-00005i-Hi; Sun, 15 Dec 2019 00:07:50 +0100 From: Heiko =?ISO-8859-1?Q?St=FCbner?= To: Sam Ravnborg Cc: thierry.reding@gmail.com, mark.rutland@arm.com, devicetree@vger.kernel.org, Heiko Stuebner , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, robh+dt@kernel.org, christoph.muellner@theobroma-systems.com Subject: Re: [PATCH 3/3] drm/panel: add panel driver for Xinpeng XPP055C272 panels Date: Sun, 15 Dec 2019 00:07:49 +0100 Message-ID: <2272108.TFxdGdtKl4@diego> In-Reply-To: <20191214081730.GC22818@ravnborg.org> References: <20191209144208.4863-1-heiko@sntech.de> <20191209144208.4863-3-heiko@sntech.de> <20191214081730.GC22818@ravnborg.org> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Hi Sam, thanks for the thorough review :-) Am Samstag, 14. Dezember 2019, 09:17:30 CET schrieb Sam Ravnborg: > > +#define dsi_generic_write_seq(dsi, cmd, seq...) do { \ > > + static const u8 d[] = { seq }; \ > > + int ret; \ > > + ret = mipi_dsi_dcs_write(dsi, cmd, d, ARRAY_SIZE(d)); \ > > + if (ret < 0) \ > > + return ret; \ > > + } while (0) > This macro return an error code if a write fails. > > > + > > +static int xpp055c272_init_sequence(struct xpp055c272 *ctx) > > +{ > > + struct mipi_dsi_device *dsi = to_mipi_dsi_device(ctx->dev); > > + struct device *dev = ctx->dev; > > + int ret; > > + > > + /* > > + * Init sequence was supplied by the panel vendor without much > > + * documentation. > > + */ > > + dsi_generic_write_seq(dsi, XPP055C272_CMD_SETEXTC, 0xf1, 0x12, 0x83); > But all uses of the macro here ignore the error. hmm, am I way off track here? dsi_generic_write_seq(dsi, XPP055C272_CMD_SETEXTC, 0xf1, 0x12, 0x83); dsi_generic_write_seq(dsi, XPP055C272_CMD_SETMIPI, 0x33, 0x81, 0x05, 0xf9, 0x0e, 0x0e, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x44, 0x25, 0x00, 0x91, 0x0a, 0x00, 0x00, 0x02, 0x4f, 0x01, 0x00, 0x00, 0x37); ... should just expand to do { static const u8 d[] = { 0xf1, 0x12, 0x83 }; int ret; ret = mipi_dsi_dcs_write(dsi, XPP055C272_CMD_SETEXTC, d, ARRAY_SIZE(d)); if (ret < 0) return ret; } while (0) do { static const u8 d[] = { 0x33, 0x81, 0x05, 0xf9, 0x0e, 0x0e, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x44, 0x25, 0x00, 0x91, 0x0a, 0x00, 0x00, 0x02, 0x4f, 0x01, 0x00, 0x00, 0x37 }; int ret; ret = mipi_dsi_dcs_write(dsi, XPP055C272_CMD_SETMIPI, d, ARRAY_SIZE(d)); if (ret < 0) return ret; } while (0) ... so every write instance will actually return an error if it happens and not continue on with the next init item. Or I'm not thinking correctly at 0:07 ;-) Heiko