From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C1B96221271; Wed, 3 Dec 2025 02:24:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.167.242.64 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764728695; cv=none; b=SjWo+kVPN2OVsA0LE0dXwLDL/OesFq01kKuxoFYZD1sr33suWTr9EXWEsKEeJLjWA6qmL7wKZuMMBo2hAUqlvvNA8Vdtl4TcFTN6NXsniL/V0JPzOOQUSjkDmafUaJ/JfMXUGK9ysxwDSoI1Sh+LQEDwEWWkk3r8/DDkPI2cJfw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764728695; c=relaxed/simple; bh=wT2DANF+meWmSjCurwWa1uu27bdlxRsyR8fhhcZwSjA=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=BKIATw7Tlyl9o3m8jdVvO6iOQn9X8McoZFJUiDFMP55Iv1wXu9nbsJbAUWnKiU0TUtLJdSCU8lcZtZU7V4mGcobKoYEu0JXStcIB+JN5RQ37hOSQo9lJ0AoU+EypUA01OQL+rLBlK+YCdCRf5yr496PG+6wZVcsrzpzqcDkQmhE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ideasonboard.com; spf=pass smtp.mailfrom=ideasonboard.com; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b=Zm9LEz3s; arc=none smtp.client-ip=213.167.242.64 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="Zm9LEz3s" Received: from pendragon.ideasonboard.com (p100198.f.east.v6connect.net [221.113.100.198]) by perceval.ideasonboard.com (Postfix) with UTF8SMTPSA id BB07BB5; Wed, 3 Dec 2025 03:22:35 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1764728556; bh=wT2DANF+meWmSjCurwWa1uu27bdlxRsyR8fhhcZwSjA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Zm9LEz3sW38O4ZicxkXZc0V/Iro4w3X7zJjw8KNFg+2ze6yk/mBYJpq2i9srsjXHe S69TuDVchr9BOtbQbMRWe5LGjY5mMH5toCiM33oU4/VIyO84bhyH5lttU7EHlNuiLq 1ap/LVMcMVzAig95ZgWZDrtJgj5flUTki7OgIUSo= Date: Wed, 3 Dec 2025 11:24:30 +0900 From: Laurent Pinchart To: Marek Vasut Cc: dri-devel@lists.freedesktop.org, David Airlie , Geert Uytterhoeven , Kieran Bingham , Maarten Lankhorst , Magnus Damm , Maxime Ripard , Simona Vetter , Thomas Zimmermann , Tomi Valkeinen , linux-kernel@vger.kernel.org, linux-renesas-soc@vger.kernel.org Subject: Re: [PATCH v2] drm/rcar-du: dsi: Handle both DRM_MODE_FLAG_N.SYNC and !DRM_MODE_FLAG_P.SYNC Message-ID: <20251203022430.GK8219@pendragon.ideasonboard.com> References: <20251202181146.138365-1-marek.vasut+renesas@mailbox.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20251202181146.138365-1-marek.vasut+renesas@mailbox.org> Hi Marek, Thank you for the patch. On Tue, Dec 02, 2025 at 07:11:06PM +0100, Marek Vasut wrote: > Since commit 94fe479fae96 ("drm/rcar-du: dsi: Clean up handling of DRM mode flags") > the driver does not set TXVMVPRMSET0R_VSPOL_LOW and TXVMVPRMSET0R_HSPOL_LOW > for modes which set neither DRM_MODE_FLAG_[PN].SYNC. The previous behavior > was to assume that neither flag means DRM_MODE_FLAG_N.SYNC . Restore the > previous behavior for maximum compatibility. > > The change of behavior is visible below, consider Vertical mode->flags > for simplicity sake, although the same applies to Horizontal ones: > > Before 94fe479fae96 ("drm/rcar-du: dsi: Clean up handling of DRM mode flags") : > > - DRM_MODE_FLAG_PVSYNC => vprmset0r |= 0 > - DRM_MODE_FLAG_NVSYNC => vprmset0r |= TXVMVPRMSET0R_VSPOL_LOW > - Neither DRM_MODE_FLAG_[PN]VSYNC => vprmset0r |= TXVMVPRMSET0R_VSPOL_LOW > > After 94fe479fae96 ("drm/rcar-du: dsi: Clean up handling of DRM mode flags") : > > - DRM_MODE_FLAG_PVSYNC => vprmset0r |= 0 > - DRM_MODE_FLAG_NVSYNC => vprmset0r |= TXVMVPRMSET0R_VSPOL_LOW > - Neither DRM_MODE_FLAG_[PN]VSYNC => vprmset0r |= 0 <---------- This broke > > The "Neither" case behavior is different, because DRM_MODE_FLAG_N[HV]SYNC is > really not equivalent !DRM_MODE_FLAG_P[HV]SYNC . > > Fixes: 94fe479fae96 ("drm/rcar-du: dsi: Clean up handling of DRM mode flags") > Signed-off-by: Marek Vasut Reviewed-by: Laurent Pinchart > --- > Cc: David Airlie > Cc: Geert Uytterhoeven > Cc: Kieran Bingham > Cc: Laurent Pinchart > Cc: Maarten Lankhorst > Cc: Magnus Damm > Cc: Maxime Ripard > Cc: Simona Vetter > Cc: Thomas Zimmermann > Cc: Tomi Valkeinen > Cc: dri-devel@lists.freedesktop.org > Cc: linux-kernel@vger.kernel.org > Cc: linux-renesas-soc@vger.kernel.org > --- > V2: - Update commit message > - Use only !P[HV]SYNC > --- > drivers/gpu/drm/renesas/rcar-du/rcar_mipi_dsi.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/renesas/rcar-du/rcar_mipi_dsi.c b/drivers/gpu/drm/renesas/rcar-du/rcar_mipi_dsi.c > index 9413b76d0bfce..4ef2e3c129ed7 100644 > --- a/drivers/gpu/drm/renesas/rcar-du/rcar_mipi_dsi.c > +++ b/drivers/gpu/drm/renesas/rcar-du/rcar_mipi_dsi.c > @@ -492,9 +492,9 @@ static void rcar_mipi_dsi_set_display_timing(struct rcar_mipi_dsi *dsi, > > /* Configuration for Video Parameters, input is always RGB888 */ > vprmset0r = TXVMVPRMSET0R_BPP_24; > - if (mode->flags & DRM_MODE_FLAG_NVSYNC) > + if (!(mode->flags & DRM_MODE_FLAG_PVSYNC)) > vprmset0r |= TXVMVPRMSET0R_VSPOL_LOW; > - if (mode->flags & DRM_MODE_FLAG_NHSYNC) > + if (!(mode->flags & DRM_MODE_FLAG_PHSYNC)) > vprmset0r |= TXVMVPRMSET0R_HSPOL_LOW; > > vprmset1r = TXVMVPRMSET1R_VACTIVE(mode->vdisplay) -- Regards, Laurent Pinchart