From patchwork Wed Sep 12 07:52:09 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jingoo Han X-Patchwork-Id: 1441371 Return-Path: X-Original-To: patchwork-linux-fbdev@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork2.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork2.kernel.org (Postfix) with ESMTP id C3AC6DF28C for ; Wed, 12 Sep 2012 07:52:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751231Ab2ILHwN (ORCPT ); Wed, 12 Sep 2012 03:52:13 -0400 Received: from mailout1.samsung.com ([203.254.224.24]:45572 "EHLO mailout1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751055Ab2ILHwL (ORCPT ); Wed, 12 Sep 2012 03:52:11 -0400 Received: from epcpsbgm1.samsung.com (epcpsbgm1 [203.254.230.26]) by mailout1.samsung.com (Oracle Communications Messaging Server 7u4-24.01(7.0.4.24.0) 64bit (built Nov 17 2011)) with ESMTP id <0MA800DZF8I0DFL0@mailout1.samsung.com> for linux-fbdev@vger.kernel.org; Wed, 12 Sep 2012 16:52:09 +0900 (KST) X-AuditID: cbfee61a-b7fba6d000007d5f-c5-50503f29b4e0 Received: from epmmp2 ( [203.254.227.17]) by epcpsbgm1.samsung.com (EPCPMTA) with SMTP id 86.5A.32095.92F30505; Wed, 12 Sep 2012 16:52:09 +0900 (KST) Received: from DOJG1HAN02 ([12.23.119.56]) by mmp2.samsung.com (Oracle Communications Messaging Server 7u4-24.01 (7.0.4.24.0) 64bit (built Nov 17 2011)) with ESMTPA id <0MA8009978IX6FC0@mmp2.samsung.com> for linux-fbdev@vger.kernel.org; Wed, 12 Sep 2012 16:52:09 +0900 (KST) From: Jingoo Han To: 'Florian Tobias Schandinat' Cc: linux-fbdev@vger.kernel.org, 'Jingoo Han' Subject: [PATCH] video: exynos_dp: increase AUX channel voltage level Date: Wed, 12 Sep 2012 16:52:09 +0900 Message-id: <003e01cd90bb$8332a1b0$8997e510$%han@samsung.com> MIME-version: 1.0 Content-type: text/plain; charset=us-ascii Content-transfer-encoding: 7bit X-Mailer: Microsoft Office Outlook 12.0 Thread-index: Ac2Qu3+lSu7gEBZeRKqqQInV4Kb9mg== Content-language: ko x-cr-hashedpuzzle: A5DP G7bh KC8+ K88+ Mc4c OzcE O7R9 O93d PuWH VhXl WV/w WmjV XHY2 d9wy gCtW kWZ7; 3; ZgBsAG8AcgBpAGEAbgBzAGMAaABhAG4AZABpAG4AYQB0AEAAZwBtAHgALgBkAGUAOwBqAGcAMQAuAGgAYQBuAEAAcwBhAG0AcwB1AG4AZwAuAGMAbwBtADsAbABpAG4AdQB4AC0AZgBiAGQAZQB2AEAAdgBnAGUAcgAuAGsAZQByAG4AZQBsAC4AbwByAGcA; Sosha1_v1; 7; {F0A33B97-A9B9-415C-9026-D51F0EB2EC06}; agBnADEALgBoAGEAbgBAAHMAYQBtAHMAdQBuAGcALgBjAG8AbQA=; Wed, 12 Sep 2012 07:52:03 GMT; WwBQAEEAVABDAEgAXQAgAHYAaQBkAGUAbwA6ACAAZQB4AHkAbgBvAHMAXwBkAHAAOgAgAGkAbgBjAHIAZQBhAHMAZQAgAEEAVQBYACAAYwBoAGEAbgBuAGUAbAAgAHYAbwBsAHQAYQBnAGUAIABsAGUAdgBlAGwA x-cr-puzzleid: {F0A33B97-A9B9-415C-9026-D51F0EB2EC06} X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFjrFLMWRmVeSWpSXmKPExsVy+t9jQV1N+4AAgwWtlhYn+j6wOjB6fN4k F8AYxWWTkpqTWZZapG+XwJXxvn0CW8Ep3opzO54zNTAu4u5i5OSQEDCR2P7lIyOELSZx4d56 ti5GLg4hgemMEh/O/maGcGYxSUzftJ0ZpIpNQE3iy5fD7F2MHBwiAlYSm7ZqgoSZBZwlJtw4 wQZiCwu4Shw5tYcFxGYRUJWYfrubFaScV8BW4uJyW5Awr4CgxI/J91ggWrUk1u88zgRhy0ts XvOWGaRcQkBd4tFfXZCwiICeRN/nq8wQJSIS+168gzr5CovEz++OEOWmEks+c0xgFJqFZMEs JAtmIVkwC8mkBYwsqxhFUwuSC4qT0nMN9YoTc4tL89L1kvNzNzGCQ/iZ1A7GlQ0WhxgFOBiV eHhPVPoHCLEmlhVX5h5ilOBgVhLh3aAbECDEm5JYWZValB9fVJqTWnyIUZqDRUmc1+mcXYCQ QHpiSWp2ampBahFMlomDU6qBsXiCbmg259F0k2PzZ4RWfXaQNA7gnMQiMOOK0kmx2NfS8ydG 1bVtubykJevsDhu/c5yWLpPM/sbyzhH8dnCaRX3wjeel53t+5HbUCvLJxnwtl7/sJZo8keFV 6KTvd0TSkgUFLL3vR93ay3/gttYyE643stEWPzsV1u7R3/Fkc6+LZs+ZRR1FSizFGYmGWsxF xYkAXY1foV0CAAA= Sender: linux-fbdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fbdev@vger.kernel.org The value of AUX channel differential amplitude current is changed from 8 mA to 16 mA, in order to increase AUX channel voltage level. In this case, AUX channel voltage level can be changed from 400 mV to 800 mV, when resistance between AUX TX and RX is 100 ohm. According to DP spec, although the normative voltage level is 390 mV, the informative voltage level is 430 mV. So, 800 mV can be helpful to improve voltage margin of AUX channel. Signed-off-by: Jingoo Han --- drivers/video/exynos/exynos_dp_reg.c | 2 +- drivers/video/exynos/exynos_dp_reg.h | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/video/exynos/exynos_dp_reg.c b/drivers/video/exynos/exynos_dp_reg.c index 20e441f..5fd1214 100644 --- a/drivers/video/exynos/exynos_dp_reg.c +++ b/drivers/video/exynos/exynos_dp_reg.c @@ -77,7 +77,7 @@ void exynos_dp_init_analog_param(struct exynos_dp_device *dp) writel(reg, dp->reg_base + EXYNOS_DP_ANALOG_CTL_3); reg = PD_RING_OSC | AUX_TERMINAL_CTRL_50_OHM | - TX_CUR1_2X | TX_CUR_8_MA; + TX_CUR1_2X | TX_CUR_16_MA; writel(reg, dp->reg_base + EXYNOS_DP_PLL_FILTER_CTL_1); reg = CH3_AMP_400_MV | CH2_AMP_400_MV | diff --git a/drivers/video/exynos/exynos_dp_reg.h b/drivers/video/exynos/exynos_dp_reg.h index 125b27c..0e79031 100644 --- a/drivers/video/exynos/exynos_dp_reg.h +++ b/drivers/video/exynos/exynos_dp_reg.h @@ -187,7 +187,7 @@ #define PD_RING_OSC (0x1 << 6) #define AUX_TERMINAL_CTRL_50_OHM (0x2 << 4) #define TX_CUR1_2X (0x1 << 2) -#define TX_CUR_8_MA (0x2 << 0) +#define TX_CUR_16_MA (0x3 << 0) /* EXYNOS_DP_TX_AMP_TUNING_CTL */ #define CH3_AMP_400_MV (0x0 << 24)