From patchwork Fri Sep 9 11:10:49 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mika Kahola X-Patchwork-Id: 9322981 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 5EF1360869 for ; Fri, 9 Sep 2016 11:11:11 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 5219529DEE for ; Fri, 9 Sep 2016 11:11:11 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 4688629DF5; Fri, 9 Sep 2016 11:11:11 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id B613029DEF for ; Fri, 9 Sep 2016 11:11:10 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 9017B6E7A5; Fri, 9 Sep 2016 11:11:06 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by gabe.freedesktop.org (Postfix) with ESMTPS id 79C976E7A1; Fri, 9 Sep 2016 11:11:05 +0000 (UTC) Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by orsmga103.jf.intel.com with ESMTP; 09 Sep 2016 04:11:06 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.30,304,1470726000"; d="scan'208";a="166201798" Received: from sorvi.fi.intel.com ([10.237.72.167]) by fmsmga004.fm.intel.com with ESMTP; 09 Sep 2016 04:11:04 -0700 From: Mika Kahola To: dri-devel@lists.freedesktop.org Date: Fri, 9 Sep 2016 14:10:49 +0300 Message-Id: <1473419458-17080-4-git-send-email-mika.kahola@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1473419458-17080-1-git-send-email-mika.kahola@intel.com> References: <1473419458-17080-1-git-send-email-mika.kahola@intel.com> Cc: daniel.vetter@ffwll.ch, intel-gfx@lists.freedesktop.org Subject: [Intel-gfx] [PATCH v9 03/12] drm: Helper to read max clock rate X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" X-Virus-Scanned: ClamAV using ClamSMTP Helper routine to read out maximum supported pixel rate for DisplayPort legay VGA converter or TMDS clock rate for other digital legacy converters. The helper returns clock rate in kHz. v2: Return early if detailed port cap info is not available. Replace if-else ladder with switch-case (Ville) Reviewed-by: Jim Bride Signed-off-by: Mika Kahola --- drivers/gpu/drm/drm_dp_helper.c | 33 +++++++++++++++++++++++++++++++++ include/drm/drm_dp_helper.h | 2 ++ 2 files changed, 35 insertions(+) diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c index 031c4d3..7497490 100644 --- a/drivers/gpu/drm/drm_dp_helper.c +++ b/drivers/gpu/drm/drm_dp_helper.c @@ -439,6 +439,39 @@ int drm_dp_link_configure(struct drm_dp_aux *aux, struct drm_dp_link *link) } EXPORT_SYMBOL(drm_dp_link_configure); +/** + * drm_dp_downstream_max_clock() - extract branch device max + * pixel rate for legacy VGA + * converter or max TMDS clock + * rate for others + * @dpcd: DisplayPort configuration data + * @port_cap: port capabilities + * + * Returns max clock in kHz on success or 0 if max clock not defined + */ +int drm_dp_downstream_max_clock(const u8 dpcd[DP_RECEIVER_CAP_SIZE], + const u8 port_cap[4]) +{ + int type = port_cap[0] & DP_DS_PORT_TYPE_MASK; + bool detailed_cap_info = dpcd[DP_DOWNSTREAMPORT_PRESENT] & + DP_DETAILED_CAP_INFO_AVAILABLE; + + if (!detailed_cap_info) + return 0; + + switch (type) { + case DP_DS_PORT_TYPE_VGA: + return port_cap[1] * 8 * 1000; + case DP_DS_PORT_TYPE_DVI: + case DP_DS_PORT_TYPE_HDMI: + case DP_DS_PORT_TYPE_DP_DUALMODE: + return port_cap[1] * 2500; + default: + return 0; + } +} +EXPORT_SYMBOL(drm_dp_downstream_max_clock); + /* * I2C-over-AUX implementation */ diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h index 0d84046..60dd9dc 100644 --- a/include/drm/drm_dp_helper.h +++ b/include/drm/drm_dp_helper.h @@ -815,6 +815,8 @@ int drm_dp_link_probe(struct drm_dp_aux *aux, struct drm_dp_link *link); int drm_dp_link_power_up(struct drm_dp_aux *aux, struct drm_dp_link *link); int drm_dp_link_power_down(struct drm_dp_aux *aux, struct drm_dp_link *link); int drm_dp_link_configure(struct drm_dp_aux *aux, struct drm_dp_link *link); +int drm_dp_downstream_max_clock(const u8 dpcd[DP_RECEIVER_CAP_SIZE], + const u8 port_cap[4]); void drm_dp_aux_init(struct drm_dp_aux *aux); int drm_dp_aux_register(struct drm_dp_aux *aux);