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=-19.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT 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 F2422C433EF for ; Thu, 16 Sep 2021 16:53:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D382A63268 for ; Thu, 16 Sep 2021 16:53:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345991AbhIPQyU (ORCPT ); Thu, 16 Sep 2021 12:54:20 -0400 Received: from mail.kernel.org ([198.145.29.99]:59206 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S245082AbhIPQsF (ORCPT ); Thu, 16 Sep 2021 12:48:05 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id BEFE56124B; Thu, 16 Sep 2021 16:27:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1631809632; bh=DLsL0fEIJu4CmK1/of73Xd2UD5LwRFimUx9537icPPA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Hmbg9c8Ku0WxSDZhbyypLX8Nc3qSTH4qxMRLfLSlZ9vEP4fUrKKbrCaJZ5hnB1+V3 5DTJ9figYp7CFWt5sHtjuG+ihwNY/A7ISLNQI43QEnVgRGdYPdJ86Zx6liMKOJ6/27 6vDLy1yeuR6aCyNa5JVfrHBM6/yH3HsFewXGZp8U= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Umang Jain , Laurent Pinchart , Dave Stevenson , Sakari Ailus , Mauro Carvalho Chehab , Sasha Levin Subject: [PATCH 5.13 226/380] media: imx258: Limit the max analogue gain to 480 Date: Thu, 16 Sep 2021 17:59:43 +0200 Message-Id: <20210916155811.774299909@linuxfoundation.org> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20210916155803.966362085@linuxfoundation.org> References: <20210916155803.966362085@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 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 b3fa28d05fa6..cdeaaec31879 100644 --- a/drivers/media/i2c/imx258.c +++ b/drivers/media/i2c/imx258.c @@ -47,7 +47,7 @@ /* 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