From patchwork Fri Jul 8 18:20:55 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Geert Uytterhoeven X-Patchwork-Id: 12911615 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 075A1CCA483 for ; Fri, 8 Jul 2022 18:21:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238929AbiGHSVd (ORCPT ); Fri, 8 Jul 2022 14:21:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41076 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238767AbiGHSVT (ORCPT ); Fri, 8 Jul 2022 14:21:19 -0400 Received: from albert.telenet-ops.be (albert.telenet-ops.be [IPv6:2a02:1800:110:4::f00:1a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 08525D12C for ; Fri, 8 Jul 2022 11:21:17 -0700 (PDT) Received: from ramsan.of.borg ([84.195.186.194]) by albert.telenet-ops.be with bizsmtp id siM72700Q4C55Sk06iM7W4; Fri, 08 Jul 2022 20:21:09 +0200 Received: from rox.of.borg ([192.168.97.57]) by ramsan.of.borg with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1o9sbD-002fGu-4u; Fri, 08 Jul 2022 20:21:07 +0200 Received: from geert by rox.of.borg with local (Exim 4.93) (envelope-from ) id 1o9sbC-00BtKA-Ld; Fri, 08 Jul 2022 20:21:06 +0200 From: Geert Uytterhoeven To: Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Daniel Vetter Cc: dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org, linux-m68k@vger.kernel.org, linux-kernel@vger.kernel.org, Geert Uytterhoeven , Javier Martinez Canillas Subject: [PATCH/RFC v3 10/10] drm/fourcc: Add DRM_FORMAT_D[1248] Date: Fri, 8 Jul 2022 20:20:55 +0200 Message-Id: <6119f3abeda9baaa88652843960adc032da276b4.1657294931.git.geert@linux-m68k.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-fbdev@vger.kernel.org As Rn covers single-channel formats with a direct relationship between channel value and brightness, and Cn can be any colors, there are currently no fourcc codes to describe single-channel formats with an inverse relationship between channel value and brightness. Introduce fourcc codes for a single-channel frame buffer format with two, four, sixteen, or 256 brightness ("darkness") levels, where there is an inverse relationship between channel value and brightness. As the number of bits per pixel may be less than eight, some of these formats rely on proper block handling for the calculation of bits per pixel and pitch. The fill order (the order in which multiple pixels are packed in a byte) is the same order as used for grayscale (2, 4, and 16 levels) images in the PNG specification, Version 1.2. This order is also the recommended and default order (FillOrder = 1) for bilevel and grayscale (16 levels) images in the TIFF 6.0 Specification, and is also used for monochrome images in the PBM file format, monochrome Linux frame buffer logos, and BDF and PSF (Linux kernel) font files. Signed-off-by: Geert Uytterhoeven Reviewed-by: Javier Martinez Canillas --- RFC, as I have no immediate need for these formats. v3: - Add Reviewed-by, - Document fill order, - Replace light-on-dark/dark-on-light by direct/inverse relationship between channel value and brightness, v2: - Add rationale for adding new formats, - Improve pixel description, - Add D[248] for completeness. --- drivers/gpu/drm/drm_fourcc.c | 7 +++++++ include/uapi/drm/drm_fourcc.h | 12 ++++++++++++ 2 files changed, 19 insertions(+) diff --git a/drivers/gpu/drm/drm_fourcc.c b/drivers/gpu/drm/drm_fourcc.c index 05e65e9ab0c69c6a..e09331bb3bc73f21 100644 --- a/drivers/gpu/drm/drm_fourcc.c +++ b/drivers/gpu/drm/drm_fourcc.c @@ -154,6 +154,13 @@ const struct drm_format_info *__drm_format_info(u32 format) { .format = DRM_FORMAT_C4, .depth = 4, .num_planes = 1, .char_per_block = { 1, }, .block_w = { 2, }, .block_h = { 1, }, .hsub = 1, .vsub = 1, .is_color_indexed = true }, { .format = DRM_FORMAT_C8, .depth = 8, .num_planes = 1, .cpp = { 1, 0, 0 }, .hsub = 1, .vsub = 1, .is_color_indexed = true }, + { .format = DRM_FORMAT_D1, .depth = 1, .num_planes = 1, + .char_per_block = { 1, }, .block_w = { 8, }, .block_h = { 1, }, .hsub = 1, .vsub = 1 }, + { .format = DRM_FORMAT_D2, .depth = 2, .num_planes = 1, + .char_per_block = { 1, }, .block_w = { 4, }, .block_h = { 1, }, .hsub = 1, .vsub = 1 }, + { .format = DRM_FORMAT_D4, .depth = 4, .num_planes = 1, + .char_per_block = { 1, }, .block_w = { 2, }, .block_h = { 1, }, .hsub = 1, .vsub = 1 }, + { .format = DRM_FORMAT_D8, .depth = 8, .num_planes = 1, .cpp = { 1, 0, 0 }, .hsub = 1, .vsub = 1 }, { .format = DRM_FORMAT_R1, .depth = 1, .num_planes = 1, .char_per_block = { 1, }, .block_w = { 8, }, .block_h = { 1, }, .hsub = 1, .vsub = 1 }, { .format = DRM_FORMAT_R2, .depth = 2, .num_planes = 1, diff --git a/include/uapi/drm/drm_fourcc.h b/include/uapi/drm/drm_fourcc.h index 6db4f195d6a15129..7eff27eca7ce707f 100644 --- a/include/uapi/drm/drm_fourcc.h +++ b/include/uapi/drm/drm_fourcc.h @@ -104,6 +104,18 @@ extern "C" { #define DRM_FORMAT_C4 fourcc_code('C', '4', ' ', ' ') /* [7:0] C0:C1 4:4 two pixels/byte */ #define DRM_FORMAT_C8 fourcc_code('C', '8', ' ', ' ') /* [7:0] C */ +/* 1 bpp Darkness (inverse relationship between channel value and brightness) */ +#define DRM_FORMAT_D1 fourcc_code('D', '1', ' ', ' ') /* [7:0] D0:D1:D2:D3:D4:D5:D6:D7 1:1:1:1:1:1:1:1 eight pixels/byte */ + +/* 2 bpp Darkness (inverse relationship between channel value and brightness) */ +#define DRM_FORMAT_D2 fourcc_code('D', '2', ' ', ' ') /* [7:0] D0:D1:D2:D3 2:2:2:2 four pixels/byte */ + +/* 4 bpp Darkness (inverse relationship between channel value and brightness) */ +#define DRM_FORMAT_D4 fourcc_code('D', '4', ' ', ' ') /* [7:0] D0:D1 4:4 two pixels/byte */ + +/* 8 bpp Darkness (inverse relationship between channel value and brightness) */ +#define DRM_FORMAT_D8 fourcc_code('D', '8', ' ', ' ') /* [7:0] D */ + /* 1 bpp Red (direct relationship between channel value and brightness) */ #define DRM_FORMAT_R1 fourcc_code('R', '1', ' ', ' ') /* [7:0] R0:R1:R2:R3:R4:R5:R6:R7 1:1:1:1:1:1:1:1 eight pixels/byte */