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=-6.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,T_DKIMWL_WL_HIGH,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 EEE29C282DD for ; Thu, 23 May 2019 19:12:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C67C9217D9 for ; Thu, 23 May 2019 19:12:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1558638776; bh=fvZOAFP5AIRVhhIqDeRi4wXWN+GCiBS8EQcBL1t27ak=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=tVzGqgf/EM/9R0ToLC/TAl2zF0K9srKz90WDnce2M+Pgz7eFSkiFfQ+2SBumd7+Gp hIeK/FWEsl3whqU4CpvZLB8VJGTPTmVn7KcfYmXPUxfpakysKrTBsTFfYCFRStYDS3 dcpwGbqZhb2OmNnv/OJNIcijQAOzkMOfGFui+UQw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731950AbfEWTMz (ORCPT ); Thu, 23 May 2019 15:12:55 -0400 Received: from mail.kernel.org ([198.145.29.99]:46668 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731801AbfEWTMu (ORCPT ); Thu, 23 May 2019 15:12:50 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 2CEC621855; Thu, 23 May 2019 19:12:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1558638769; bh=fvZOAFP5AIRVhhIqDeRi4wXWN+GCiBS8EQcBL1t27ak=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=z2QFKmtzmTWK5M3iCyZ7yBA1UemX6uMAOrJEwABjMWBLZEB+xZ4o9V/npQ2MXB4U/ P2irRN+4J1t1UKN9tvZ8AaeZyoe5cOx7qX7ZjmMI2y4miosKioeH0cmSgW/fQ7lTt8 /UZYi/QDHsUivxUAROMtVkaEusV9q2mXyoUjYjuo= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Yifeng Li , Sudip Mukherjee , Teddy Wang , Bartlomiej Zolnierkiewicz Subject: [PATCH 4.14 41/77] fbdev: sm712fb: fix brightness control on reboot, dont set SR30 Date: Thu, 23 May 2019 21:05:59 +0200 Message-Id: <20190523181725.844396449@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190523181719.982121681@linuxfoundation.org> References: <20190523181719.982121681@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Yifeng Li commit 5481115e25e42b9215f2619452aa99c95f08492f upstream. On a Thinkpad s30 (Pentium III / i440MX, Lynx3DM), rebooting with sm712fb framebuffer driver would cause the role of brightness up/down button to swap. Experiments showed the FPR30 register caused this behavior. Moreover, even if this register don't have side-effect on other systems, over- writing it is also highly questionable, since it was originally configurated by the motherboard manufacturer by hardwiring pull-down resistors to indicate the type of LCD panel. We should not mess with it. Stop writing to the SR30 (a.k.a FPR30) register. Signed-off-by: Yifeng Li Tested-by: Sudip Mukherjee Cc: Teddy Wang Cc: # v4.4+ Signed-off-by: Bartlomiej Zolnierkiewicz Signed-off-by: Greg Kroah-Hartman --- drivers/video/fbdev/sm712fb.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/video/fbdev/sm712fb.c +++ b/drivers/video/fbdev/sm712fb.c @@ -1145,8 +1145,8 @@ static void sm7xx_set_timing(struct smtc /* init SEQ register SR30 - SR75 */ for (i = 0; i < SIZE_SR30_SR75; i++) - if ((i + 0x30) != 0x62 && (i + 0x30) != 0x6a && - (i + 0x30) != 0x6b) + if ((i + 0x30) != 0x30 && (i + 0x30) != 0x62 && + (i + 0x30) != 0x6a && (i + 0x30) != 0x6b) smtc_seqw(i + 0x30, vgamode[j].init_sr30_sr75[i]);