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=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 C9EEAC433EF for ; Thu, 9 Sep 2021 13:39:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AAC5361206 for ; Thu, 9 Sep 2021 13:39:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345112AbhIINlA (ORCPT ); Thu, 9 Sep 2021 09:41:00 -0400 Received: from mail.kernel.org ([198.145.29.99]:58636 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1356619AbhIIMzd (ORCPT ); Thu, 9 Sep 2021 08:55:33 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id F2AD063253; Thu, 9 Sep 2021 11:58:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1631188692; bh=sQw9MZjQniyUBF22K2BBv1mR9r1y/Ody4+hAHNxdgZQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=CG8DdKq+UfH7tLdkBQWfdypmG/4fdAaZT4Qve7xQ1bdyR2sVBoqH+O05rNl/e3Zsv d3XdWVoSqCfj7LUoLO8Vt9MrnmaGqKzDJMgXdq1NKJWAU4zJjhUIybs0agrrALCJc0 zr1Ka0QrmaonItyYqrj2Wj0KWH/oxoHckTfAx2UGOpLbcBKm2OxJaD1tOFH7dsGSwP 3W8lmEKwVhss3mihy01gZWhA57QotfkbXfzzSYhYdtbV1MgF8GIDYu/uSj7MYw9WW5 TUx1lLMOrxwTvopYjRT9j9g5zLZm+45xbDXW7U5kX8i63NF/5gwkZZsNYuWfAlBwCu QjDhBR/0hDO6A== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Umang Jain , Laurent Pinchart , Dave Stevenson , Sakari Ailus , Mauro Carvalho Chehab , Sasha Levin , linux-media@vger.kernel.org Subject: [PATCH AUTOSEL 4.19 37/74] media: imx258: Limit the max analogue gain to 480 Date: Thu, 9 Sep 2021 07:56:49 -0400 Message-Id: <20210909115726.149004-37-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210909115726.149004-1-sashal@kernel.org> References: <20210909115726.149004-1-sashal@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Umang Jain [ Upstream commit f809665ee75fff3f4ea8907f406a66d380aeb184 ] The range for analog gain mentioned in the datasheet is [0, 480]. The real gain formula mentioned in the datasheet is: Gain = 512 / (512 – X) Hence, values larger than 511 clearly makes no sense. The gain register field is also documented to be of 9-bits in the datasheet. Certainly, it is enough to infer that, the kernel driver currently advertises an arbitrary analog gain max. Fix it by rectifying the value as per the data sheet i.e. 480. Signed-off-by: Umang Jain Reviewed-by: Laurent Pinchart Reviewed-by: Dave Stevenson Signed-off-by: Sakari Ailus Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sasha Levin --- drivers/media/i2c/imx258.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/media/i2c/imx258.c b/drivers/media/i2c/imx258.c index 68ce63333744..85395813c0f2 100644 --- a/drivers/media/i2c/imx258.c +++ b/drivers/media/i2c/imx258.c @@ -46,7 +46,7 @@ /* Analog gain control */ #define IMX258_REG_ANALOG_GAIN 0x0204 #define IMX258_ANA_GAIN_MIN 0 -#define IMX258_ANA_GAIN_MAX 0x1fff +#define IMX258_ANA_GAIN_MAX 480 #define IMX258_ANA_GAIN_STEP 1 #define IMX258_ANA_GAIN_DEFAULT 0x0 -- 2.30.2