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=-8.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable 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 F1673C432C0 for ; Tue, 3 Dec 2019 06:25:33 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 7BDD8206DF for ; Tue, 3 Dec 2019 06:25:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="O28pRcLT"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="h6qBeI/W" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7BDD8206DF Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ideasonboard.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=kAtyYfJjROnYE7lZIeoKE3Ujzc4BSBa/ufFdfw7bMWo=; b=O28pRcLTfVQKy7 dYrEDFNCfoIN4Xt+6pJyKcUZQMbJt1ZZpS6ZomoETZumaBKx4+OGa4VLsecbyCZbGeCgIRuE+luBN nqeVSrd/eSdaNnBRnDer7hIz79tNwYX5bKwdEEoIoS9LQGnwkrPAl/+XIhs4tihq4dVSGfKg/nPCw jCYZOcvZz+Fyq+HPtygwI4BSJIDuj4QkDeJsCejbzuBmtRZ7bLd0YkFEXT4E4oymVDVt7siSqdMcc FxKcXk3oxWjF5vUq3eY/kuz9ntGgCD34DC+D+PY56FWYDoLaUDPjRcKFhsb4G4CkcWyeJfFqi6Q9c m7IoVSvzeHYADpdsgihA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1ic1cq-0003j9-1C; Tue, 03 Dec 2019 06:25:32 +0000 Received: from perceval.ideasonboard.com ([213.167.242.64]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1ic1cW-00039B-Sv; Tue, 03 Dec 2019 06:25:15 +0000 Received: from pendragon.ideasonboard.com (81-175-216-236.bb.dnainternet.fi [81.175.216.236]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id ED8F8309; Tue, 3 Dec 2019 07:25:05 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1575354306; bh=xMhIy5HaiSKkNSrpN5V89DDzQfYcJU5ugOWimrHaPOs=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=h6qBeI/WhmgWblAgjLQFXmZpvICtdJ7ang5ZAu5QF/RWsHFhxgfKLrUQgLiN0ZySP te8cQY0l0xw5SKujiIaFAPliBjJuQRSuy8VjWqLPVlmREWdKpCygHfjb38yR1iYlaQ x2aoQRv36caeBrjXBdi/fF336MdBMzwTFlpaN1nk= Date: Tue, 3 Dec 2019 08:24:59 +0200 From: Laurent Pinchart To: Sam Ravnborg Subject: Re: [PATCH v1 01/26] drm/drm_panel: no error when no callback Message-ID: <20191203062459.GA4730@pendragon.ideasonboard.com> References: <20191202193230.21310-1-sam@ravnborg.org> <20191202193230.21310-2-sam@ravnborg.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20191202193230.21310-2-sam@ravnborg.org> User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191202_222513_390710_20B987CC X-CRM114-Status: GOOD ( 17.34 ) X-BeenThere: linux-mediatek@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Neil Armstrong , David Airlie , Linus Walleij , dri-devel@lists.freedesktop.org, Andrzej Hajda , Thierry Reding , Benjamin Gaignard , Stefan Agner , linux-samsung-soc@vger.kernel.org, linux-rockchip@lists.infradead.org, Tomi Valkeinen , NXP Linux Team , Jagan Teki , Jitao Shi , Pengutronix Kernel Team , Maarten Lankhorst , Maxime Ripard , linux-mediatek@lists.infradead.org, Abhinav Kumar , linux-tegra@vger.kernel.org, Sean Paul , linux-arm-kernel@lists.infradead.org, Purism Kernel Team , linux-renesas-soc@vger.kernel.org, Boris Brezillon , Daniel Vetter Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org Hi Sam, Thank you for the patch. On Mon, Dec 02, 2019 at 08:32:05PM +0100, Sam Ravnborg wrote: > The callbacks in drm_panel_funcs are optional, so do not > return an error just because no callback is assigned. Unless I'm mistaken the callbacks are not documented as optional. Should this be fixed too ? > Signed-off-by: Sam Ravnborg > Cc: Maarten Lankhorst > Cc: Maxime Ripard > Cc: Thierry Reding > Cc: Sam Ravnborg > Cc: David Airlie > Cc: Daniel Vetter > --- > drivers/gpu/drm/drm_panel.c | 35 +++++++++++++++++++++++++---------- > 1 file changed, 25 insertions(+), 10 deletions(-) > > diff --git a/drivers/gpu/drm/drm_panel.c b/drivers/gpu/drm/drm_panel.c > index ed7985c0535a..2d59cdd05e50 100644 > --- a/drivers/gpu/drm/drm_panel.c > +++ b/drivers/gpu/drm/drm_panel.c > @@ -151,10 +151,13 @@ EXPORT_SYMBOL(drm_panel_detach); > */ > int drm_panel_prepare(struct drm_panel *panel) > { > - if (panel && panel->funcs && panel->funcs->prepare) > + if (!panel) > + return -EINVAL; > + > + if (panel->funcs && panel->funcs->prepare) > return panel->funcs->prepare(panel); > > - return panel ? -ENOSYS : -EINVAL; > + return 0; > } > EXPORT_SYMBOL(drm_panel_prepare); > > @@ -171,10 +174,13 @@ EXPORT_SYMBOL(drm_panel_prepare); > */ > int drm_panel_unprepare(struct drm_panel *panel) > { > - if (panel && panel->funcs && panel->funcs->unprepare) > + if (!panel) > + return -EINVAL; > + > + if (panel->funcs && panel->funcs->unprepare) > return panel->funcs->unprepare(panel); > > - return panel ? -ENOSYS : -EINVAL; > + return 0; > } > EXPORT_SYMBOL(drm_panel_unprepare); > > @@ -190,10 +196,13 @@ EXPORT_SYMBOL(drm_panel_unprepare); > */ > int drm_panel_enable(struct drm_panel *panel) > { > - if (panel && panel->funcs && panel->funcs->enable) > + if (!panel) > + return -EINVAL; > + > + if (panel->funcs && panel->funcs->enable) > return panel->funcs->enable(panel); > > - return panel ? -ENOSYS : -EINVAL; > + return 0; > } > EXPORT_SYMBOL(drm_panel_enable); > > @@ -209,10 +218,13 @@ EXPORT_SYMBOL(drm_panel_enable); > */ > int drm_panel_disable(struct drm_panel *panel) > { > - if (panel && panel->funcs && panel->funcs->disable) > + if (!panel) > + return -EINVAL; > + > + if (panel->funcs && panel->funcs->disable) > return panel->funcs->disable(panel); > > - return panel ? -ENOSYS : -EINVAL; > + return 0; > } > EXPORT_SYMBOL(drm_panel_disable); > > @@ -228,10 +240,13 @@ EXPORT_SYMBOL(drm_panel_disable); > */ > int drm_panel_get_modes(struct drm_panel *panel) > { > - if (panel && panel->funcs && panel->funcs->get_modes) > + if (!panel) > + return -EINVAL; > + > + if (panel->funcs && panel->funcs->get_modes) > return panel->funcs->get_modes(panel); Should get_modes() be optional ? As far as I can tell all the panel drivers in drivers/gpu/drm/panel/ implement it, and I'm not sure to see how a panel could be usable if it can't return its mode. On the other hand you return 0 if the callback isn't implemented, which doesn't mean success here, so I suppose that's fine, but I don't think we should document .get_modes() as being optional. With these issues addressed (if they need to be), Reviewed-by: Laurent Pinchart > > - return panel ? -ENOSYS : -EINVAL; > + return 0; > } > EXPORT_SYMBOL(drm_panel_get_modes); > -- Regards, Laurent Pinchart _______________________________________________ Linux-mediatek mailing list Linux-mediatek@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-mediatek