From nobody Tue Apr 7 09:46:58 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B900AC43219 for ; Thu, 13 Oct 2022 10:51:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229505AbiJMKv4 (ORCPT ); Thu, 13 Oct 2022 06:51:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44902 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229541AbiJMKvw (ORCPT ); Thu, 13 Oct 2022 06:51:52 -0400 Received: from ironport.ite.com.tw (60-251-196-230.hinet-ip.hinet.net [60.251.196.230]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 80665FF8CC for ; Thu, 13 Oct 2022 03:51:36 -0700 (PDT) Received: from unknown (HELO mse.ite.com.tw) ([192.168.35.30]) by ironport.ite.com.tw with ESMTP; 13 Oct 2022 18:51:35 +0800 Received: from CSBMAIL1.internal.ite.com.tw (CSBMAIL1.internal.ite.com.tw [192.168.65.58]) by mse.ite.com.tw with ESMTP id 29DApUoD073259; Thu, 13 Oct 2022 18:51:30 +0800 (GMT-8) (envelope-from allen.chen@ite.com.tw) Received: from VirtualBox.internal.ite.com.tw (192.168.70.46) by CSBMAIL1.internal.ite.com.tw (192.168.65.58) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2176.14; Thu, 13 Oct 2022 18:51:31 +0800 From: allen CC: Allen Chen , Pin-yen Lin , Jau-Chih Tseng , Kenneth Hung , Hermes Wu , Andrzej Hajda , Neil Armstrong , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , David Airlie , Daniel Vetter , "open list:DRM DRIVERS" , open list Subject: [PATCH v4 2/2] drm/bridge: add it6505 driver to read data-lanes and link-frequencies from dt Date: Thu, 13 Oct 2022 18:51:14 +0800 Message-ID: <20221013105116.180380-3-allen.chen@ite.com.tw> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20221013105116.180380-1-allen.chen@ite.com.tw> References: <20221013105116.180380-1-allen.chen@ite.com.tw> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [192.168.70.46] X-ClientProxiedBy: CSBMAIL1.internal.ite.com.tw (192.168.65.58) To CSBMAIL1.internal.ite.com.tw (192.168.65.58) X-TM-SNTS-SMTP: AE3FFFA69BFB1B88C4AAB73DC9A6A3D38A4C3B34C64DA126DBA1D0564BCB07CB2002:8 X-MAIL: mse.ite.com.tw 29DApUoD073259 To: unlisted-recipients:; (no To-header on input) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: allen chen Add driver to read data-lanes and link-frequencies from dt property to restrict output bandwidth. Signed-off-by: Allen chen Signed-off-by: Pin-yen Lin --- drivers/gpu/drm/bridge/ite-it6505.c | 54 +++++++++++++++++++++++++++-- 1 file changed, 51 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/bridge/ite-it6505.c b/drivers/gpu/drm/bridge/i= te-it6505.c index a4302492cf8df..653ab38465b98 100644 --- a/drivers/gpu/drm/bridge/ite-it6505.c +++ b/drivers/gpu/drm/bridge/ite-it6505.c @@ -437,6 +437,8 @@ struct it6505 { bool powered; bool hpd_state; u32 afe_setting; + u32 max_dpi_pixel_clock; + u32 max_lane_count; enum hdcp_state hdcp_status; struct delayed_work hdcp_work; struct work_struct hdcp_wait_ksv_list; @@ -1476,7 +1478,8 @@ static void it6505_parse_link_capabilities(struct it6= 505 *it6505) it6505->lane_count =3D link->num_lanes; DRM_DEV_DEBUG_DRIVER(dev, "Sink support %d lanes training", it6505->lane_count); - it6505->lane_count =3D min_t(int, it6505->lane_count, MAX_LANE_COUNT); + it6505->lane_count =3D min_t(int, it6505->lane_count, + it6505->max_lane_count); =20 it6505->branch_device =3D drm_dp_is_branch(it6505->dpcd); DRM_DEV_DEBUG_DRIVER(dev, "Sink %sbranch device", @@ -2912,7 +2915,7 @@ it6505_bridge_mode_valid(struct drm_bridge *bridge, if (mode->flags & DRM_MODE_FLAG_INTERLACE) return MODE_NO_INTERLACE; =20 - if (mode->clock > DPI_PIXEL_CLK_MAX) + if (mode->clock > it6505->max_dpi_pixel_clock) return MODE_CLOCK_HIGH; =20 it6505->video_info.clock =3D mode->clock; @@ -3102,7 +3105,13 @@ static int it6505_init_pdata(struct it6505 *it6505) static void it6505_parse_dt(struct it6505 *it6505) { struct device *dev =3D &it6505->client->dev; + struct device_node *np =3D dev->of_node, *ep =3D NULL; + int len; + u64 link_frequencies; + u32 data_lanes[4]; u32 *afe_setting =3D &it6505->afe_setting; + u32 *max_lane_count =3D &it6505->max_lane_count; + u32 *max_dpi_pixel_clock =3D &it6505->max_dpi_pixel_clock; =20 it6505->lane_swap_disabled =3D device_property_read_bool(dev, "no-laneswap"); @@ -3118,7 +3127,46 @@ static void it6505_parse_dt(struct it6505 *it6505) } else { *afe_setting =3D 0; } - DRM_DEV_DEBUG_DRIVER(dev, "using afe_setting: %d", *afe_setting); + + len =3D of_property_read_variable_u32_array(np, "data-lanes", + data_lanes, 0, + ARRAY_SIZE(data_lanes)); + *max_lane_count =3D len; + + if (len < 0 || *max_lane_count =3D=3D 3 || *max_lane_count > 4) { + dev_err(dev, "error data-lanes, use default"); + *max_lane_count =3D MAX_LANE_COUNT; + } + + ep =3D of_graph_get_endpoint_by_regs(np, 0, 0); + + if (ep) { + len =3D of_property_read_variable_u64_array(ep, + "link-frequencies", + &link_frequencies, 0, + 1); + if (len >=3D 0) { + link_frequencies /=3D 1000; + if (link_frequencies > 297000) { + dev_err(dev, + "max pixel clock error, use default"); + *max_dpi_pixel_clock =3D DPI_PIXEL_CLK_MAX; + } else { + *max_dpi_pixel_clock =3D link_frequencies; + } + } else { + dev_err(dev, "error link frequencies, use default"); + *max_dpi_pixel_clock =3D DPI_PIXEL_CLK_MAX; + } + } else { + dev_err(dev, "error endpoint, use default"); + *max_dpi_pixel_clock =3D DPI_PIXEL_CLK_MAX; + } + + DRM_DEV_DEBUG_DRIVER(dev, "using afe_setting: %u, max_lane_count: %u", + it6505->afe_setting, it6505->max_lane_count); + DRM_DEV_DEBUG_DRIVER(dev, "using max_dpi_pixel_clock: %u kHz", + it6505->max_dpi_pixel_clock); } =20 static ssize_t receive_timing_debugfs_show(struct file *file, char __user = *buf, --=20 2.25.1