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 EC428C7619A for ; Wed, 5 Apr 2023 07:30:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237064AbjDEHab (ORCPT ); Wed, 5 Apr 2023 03:30:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43094 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230031AbjDEHa0 (ORCPT ); Wed, 5 Apr 2023 03:30:26 -0400 Received: from relay2-d.mail.gandi.net (relay2-d.mail.gandi.net [IPv6:2001:4b98:dc4:8::222]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D3A062D55 for ; Wed, 5 Apr 2023 00:30:23 -0700 (PDT) Received: from booty (unknown [77.244.183.192]) (Authenticated sender: luca.ceresoli@bootlin.com) by mail.gandi.net (Postfix) with ESMTPSA id 69A334000C; Wed, 5 Apr 2023 07:30:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1680679822; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=O56h5+y8ZPuPqlxWi1Eidn7BvjrJnSkJPZzzfeYz5iI=; b=XrW3kbJnPL7AjnLfuykuDK8Mp1Xjfky5soya2RLs1B6O+AOJYMIuoy9DnPW5dz+r3EoZTW AV6nLsajbCR38p1VhgSDw7evHVKzt8kR9iG6+HbzQa43xINjh7QEFqqxTT7J14dI++GoUL ANW6w+anaW1G0q+V7QP4LUt9DvQijouvoMwEF41AIOfu7LB4dUXwHmMJuKiiTh+AMnzNHC 4oNTubm8OvrwgI8NOjS0R22XB+pg/bbicYZf1K6h513qdxuFav0l8RCrBZCcooUdA9xyRi /h/AWJZQGKC7GNWF7ETUZQ3q5qQ7VnBI9BbyySiTXOfaQBlioJngSm9/mnV96A== Date: Wed, 5 Apr 2023 09:30:17 +0200 From: Luca Ceresoli To: Marek Vasut Cc: dri-devel@lists.freedesktop.org, Andrzej Hajda , Neil Armstrong , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , David Airlie , Daniel Vetter , linux-kernel@vger.kernel.org, Thomas Petazzoni , Paul Kocialkowski Subject: Re: [PATCH] drm: bridge: ldb: add support for using channel 1 only Message-ID: <20230405093017.62ccb4f6@booty> In-Reply-To: <5b514970-cfc8-41de-7ae6-f608f5187860@denx.de> References: <20230404073720.1465552-1-luca.ceresoli@bootlin.com> <5b514970-cfc8-41de-7ae6-f608f5187860@denx.de> Organization: Bootlin X-Mailer: Claws Mail 4.0.0 (GTK+ 3.24.33; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Marek, thanks for the quick and detailed review! On Wed, 5 Apr 2023 05:28:16 +0200 Marek Vasut wrote: > On 4/4/23 09:37, Luca Ceresoli wrote: > > [...] > > > @@ -177,28 +183,25 @@ static void fsl_ldb_atomic_enable(struct drm_bridge *bridge, > > clk_prepare_enable(fsl_ldb->clk); > > > > /* Program LDB_CTRL */ > > - reg = LDB_CTRL_CH0_ENABLE; > > - > > - if (fsl_ldb->lvds_dual_link) > > - reg |= LDB_CTRL_CH1_ENABLE | LDB_CTRL_SPLIT_MODE; > > - > > - if (lvds_format_24bpp) { > > - reg |= LDB_CTRL_CH0_DATA_WIDTH; > > - if (fsl_ldb->lvds_dual_link) > > - reg |= LDB_CTRL_CH1_DATA_WIDTH; > > - } > > - > > - if (lvds_format_jeida) { > > - reg |= LDB_CTRL_CH0_BIT_MAPPING; > > - if (fsl_ldb->lvds_dual_link) > > - reg |= LDB_CTRL_CH1_BIT_MAPPING; > > - } > > - > > - if (mode->flags & DRM_MODE_FLAG_PVSYNC) { > > - reg |= LDB_CTRL_DI0_VSYNC_POLARITY; > > - if (fsl_ldb->lvds_dual_link) > > - reg |= LDB_CTRL_DI1_VSYNC_POLARITY; > > - } > > + reg = > > Cosmetic nit, do we need the newline here , can't we just move the first > '(fsl_ldb->ch0_enabled ? LDB_CTRL_CH0_ENABLE : 0) |' on the same line as > 'reg =' ? It might need a bit of indent with spaces, but that should be OK. Sure. Maybe 'reg =(fsl...' would be even better, it checkpatch allows. > > @@ -311,10 +314,23 @@ static int fsl_ldb_probe(struct platform_device *pdev) > > if (IS_ERR(fsl_ldb->regmap)) > > return PTR_ERR(fsl_ldb->regmap); > > > > - /* Locate the panel DT node. */ > > - panel_node = of_graph_get_remote_node(dev->of_node, 1, 0); > > - if (!panel_node) > > - return -ENXIO; > > + /* Locate the remote ports and the panel node */ > > + remote1 = of_graph_get_remote_node(dev->of_node, 1, 0); > > + remote2 = of_graph_get_remote_node(dev->of_node, 2, 0); > > + fsl_ldb->ch0_enabled = (remote1 != NULL); > > + fsl_ldb->ch1_enabled = (remote2 != NULL); > > + panel_node = of_node_get(remote1 ? remote1 : remote2); > > You can even do this without the middle 'remote1' I think: > > panel_node = of_node_get(remote1 ? : remote2); Apparently, but honestly with such short expressions clearly having no side effects I think it's not helping readability. > > + of_node_put(remote1); > > + of_node_put(remote2); > > + > > + if (!fsl_ldb->ch0_enabled && !fsl_ldb->ch1_enabled) { > > + of_node_put(panel_node); > > + return dev_err_probe(dev, -ENXIO, "No panel node found"); > > + } > > + > > + dev_dbg(dev, "Using %s\n", > > + fsl_ldb_is_dual(fsl_ldb) ? "dual mode" : > > I think this is called "dual-link mode" , maybe update the string . I was using the terms from the NXP docs, but indeed in the kernel it seems that "dual-link" is the common name. Updating that. > > @@ -325,20 +341,26 @@ static int fsl_ldb_probe(struct platform_device *pdev) > > if (IS_ERR(fsl_ldb->panel_bridge)) > > return PTR_ERR(fsl_ldb->panel_bridge); > > > > - /* Determine whether this is dual-link configuration */ > > - port1 = of_graph_get_port_by_id(dev->of_node, 1); > > - port2 = of_graph_get_port_by_id(dev->of_node, 2); > > - dual_link = drm_of_lvds_get_dual_link_pixel_order(port1, port2); > > - of_node_put(port1); > > - of_node_put(port2); > > > > - if (dual_link == DRM_LVDS_DUAL_LINK_EVEN_ODD_PIXELS) { > > - dev_err(dev, "LVDS channel pixel swap not supported.\n"); > > - return -EINVAL; > > - } > > + if (fsl_ldb_is_dual(fsl_ldb)) { > > + struct device_node *port1, *port2; > > + > > + port1 = of_graph_get_port_by_id(dev->of_node, 1); > > + port2 = of_graph_get_port_by_id(dev->of_node, 2); > > + dual_link = drm_of_lvds_get_dual_link_pixel_order(port1, port2); > > + of_node_put(port1); > > + of_node_put(port2); > > > > - if (dual_link == DRM_LVDS_DUAL_LINK_ODD_EVEN_PIXELS) > > - fsl_ldb->lvds_dual_link = true; > > + if (dual_link < 0) > > + return dev_err_probe(dev, dual_link, > > + "Error getting dual link configuration"); > > Does this need a trailing '\n' in the formatting string or not ? I think > yes. Oops, good catch. > The rest looks good, with the few details fixed: > > Reviewed-by: Marek Vasut Thanks! -- Luca Ceresoli, Bootlin Embedded Linux and Kernel engineering https://bootlin.com