From patchwork Thu Sep 24 22:14:13 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ondrej Zary X-Patchwork-Id: 7261111 Return-Path: X-Original-To: patchwork-linux-fbdev@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id B74C8BEEC1 for ; Thu, 24 Sep 2015 22:14:30 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id E422120B1B for ; Thu, 24 Sep 2015 22:14:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6A0D320B02 for ; Thu, 24 Sep 2015 22:14:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754602AbbIXWO1 (ORCPT ); Thu, 24 Sep 2015 18:14:27 -0400 Received: from ns.gsystem.sk ([62.176.172.50]:53619 "EHLO gsystem.sk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754392AbbIXWO1 (ORCPT ); Thu, 24 Sep 2015 18:14:27 -0400 Received: from stip-static-68.213-81-217.telecom.sk ([213.81.217.68] helo=gsql.ggedos.sk) by gsystem.sk with esmtpsa (TLS1.1:DHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.80) (envelope-from ) id 1ZfEmU-0004yC-DH; Fri, 25 Sep 2015 00:14:22 +0200 From: Ondrej Zary To: Krzysztof Helt Cc: Tomi Valkeinen , linux-fbdev@vger.kernel.org, Kernel development list Subject: [PATCH v2 1/2] fb_ddc: Allow I2C adapters without SCL read capability Date: Fri, 25 Sep 2015 00:14:13 +0200 Message-Id: <1443132854-31786-1-git-send-email-linux@rainbow-software.org> X-Mailer: git-send-email 1.7.10.4 Sender: linux-fbdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fbdev@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP i2c-algo-bit allows I2C adapters without SCL read capability to work but fb_ddc_read fails to work on them. Fix fb_ddc_read to work with I2C adapters not capable of reading SCL. Signed-off-by: Ondrej Zary --- drivers/video/fbdev/core/fb_ddc.c | 28 ++++++++++++++++++---------- 1 file changed, 18 insertions(+), 10 deletions(-) diff --git a/drivers/video/fbdev/core/fb_ddc.c b/drivers/video/fbdev/core/fb_ddc.c index 94322cc..8bf5f2f 100644 --- a/drivers/video/fbdev/core/fb_ddc.c +++ b/drivers/video/fbdev/core/fb_ddc.c @@ -67,13 +67,17 @@ unsigned char *fb_ddc_read(struct i2c_adapter *adapter) msleep(13); algo_data->setscl(algo_data->data, 1); - for (j = 0; j < 5; j++) { - msleep(10); - if (algo_data->getscl(algo_data->data)) - break; + if (algo_data->getscl) { + for (j = 0; j < 5; j++) { + msleep(10); + if (algo_data->getscl(algo_data->data)) + break; + } + if (j == 5) + continue; + } else { + udelay(algo_data->udelay); } - if (j == 5) - continue; algo_data->setsda(algo_data->data, 0); msleep(15); @@ -89,10 +93,14 @@ unsigned char *fb_ddc_read(struct i2c_adapter *adapter) msleep(15); algo_data->setscl(algo_data->data, 1); - for (j = 0; j < 10; j++) { - msleep(10); - if (algo_data->getscl(algo_data->data)) - break; + if (algo_data->getscl) { + for (j = 0; j < 10; j++) { + msleep(10); + if (algo_data->getscl(algo_data->data)) + break; + } + } else { + udelay(algo_data->udelay); } algo_data->setsda(algo_data->data, 1);