From patchwork Wed Jul 6 11:04:47 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mika Kahola X-Patchwork-Id: 9216219 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 D900F607D9 for ; Wed, 6 Jul 2016 11:05:07 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id CA49F2882D for ; Wed, 6 Jul 2016 11:05:07 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id BF55728830; Wed, 6 Jul 2016 11:05:07 +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]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7F6822882D for ; Wed, 6 Jul 2016 11:05:07 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id EFA4A6E632; Wed, 6 Jul 2016 11:05:06 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by gabe.freedesktop.org (Postfix) with ESMTP id EDD0E6E63C; Wed, 6 Jul 2016 11:05:04 +0000 (UTC) Received: from orsmga003.jf.intel.com ([10.7.209.27]) by fmsmga102.fm.intel.com with ESMTP; 06 Jul 2016 04:05:05 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.28,318,1464678000"; d="scan'208";a="841419541" Received: from sorvi.fi.intel.com ([10.237.72.50]) by orsmga003.jf.intel.com with ESMTP; 06 Jul 2016 04:05:03 -0700 From: Mika Kahola To: dri-devel@lists.freedesktop.org Date: Wed, 6 Jul 2016 14:04:47 +0300 Message-Id: <1467803094-10473-4-git-send-email-mika.kahola@intel.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1467803094-10473-1-git-send-email-mika.kahola@intel.com> References: <1467803094-10473-1-git-send-email-mika.kahola@intel.com> Cc: daniel.vetter@ffwll.ch, intel-gfx@lists.freedesktop.org Subject: [Intel-gfx] [PATCH v6 03/10] 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) Signed-off-by: Mika Kahola Reviewed-by: Jim Bride --- 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 091053e..0d4117c 100644 --- a/drivers/gpu/drm/drm_dp_helper.c +++ b/drivers/gpu/drm/drm_dp_helper.c @@ -438,6 +438,39 @@ 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 336d742..de8e9ae 100644 --- a/include/drm/drm_dp_helper.h +++ b/include/drm/drm_dp_helper.h @@ -806,6 +806,8 @@ 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);