From patchwork Wed Dec 11 06:19:09 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hsin-Yi Wang X-Patchwork-Id: 11284503 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 2ADD213B6 for ; Wed, 11 Dec 2019 09:22:16 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 099912077B for ; Wed, 11 Dec 2019 09:22:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="mv4AwMap" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 099912077B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=chromium.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 2F3DC6EADC; Wed, 11 Dec 2019 09:20:57 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mail-pl1-x642.google.com (mail-pl1-x642.google.com [IPv6:2607:f8b0:4864:20::642]) by gabe.freedesktop.org (Postfix) with ESMTPS id 54B3F6E167 for ; Wed, 11 Dec 2019 06:19:49 +0000 (UTC) Received: by mail-pl1-x642.google.com with SMTP id bh2so981817plb.11 for ; Tue, 10 Dec 2019 22:19:49 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=76R4CRjTberWs1+4We73KltAUaIdDXYhjKx430Z9EEM=; b=mv4AwMap++Smhq2iifMvvVvhgzHcZelWKrbMDVs21ulI3vfAibQVcdmzrR2dFyjfH5 kSL3LCm0Lp3JEQlbVN2rPWAyc62ozrQh6OTrD9KY+swDxS0kAlxfxzLs5Bp0741/KhT+ ejG+JYh6yPJv9VTShDwUqWfFdtoZke6C9mAME= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=76R4CRjTberWs1+4We73KltAUaIdDXYhjKx430Z9EEM=; b=kH1BeUWR3wLsgFZsxRUUPBcaKxNFExPk7DCcVK02NUDFphGf2fFu9gFPkOhb82xl1T M9q565/kcNPPAPnIbrOCX5ToEvcKPwwnAH8pWDZfL4VqcOeAz+BpNv7lJ4w0mC4ver9w NqPtLQ3XlCrquFuJYWdLmfANyAufv48gxjpATyBIfgXp/h/TxEpc3egVjBy/7p3bRqjT vJYDAHtdNUTXJE6z0x8gJ7nV+mPV7WdK2SFzqvn11DMqSgy1zZZzPXL5ivQaayAoj4vW vXKiyfw8ZQKvEmphFxpdSA1YhMyN/ilpbEOlPqZ4FJ3sd1TFHATLB5dI3o4Lb3yabuAZ YmIQ== X-Gm-Message-State: APjAAAXHYG2pLO1qawxZlAch+sFfVKl1+5rn9C48uAu1KYOdmLK0KLTZ NXRck6YAfWHX+RSpWVh/FCQvBvb7PUT9hg== X-Google-Smtp-Source: APXvYqyQdZvJdA+Oih6UHvuV2zvAvDFmSpdCjC6sQtg13Gw0FfJ3GCCrMT68SF0qZhKyn9kNmSXMeg== X-Received: by 2002:a17:902:5a85:: with SMTP id r5mr1533808pli.222.1576045188561; Tue, 10 Dec 2019 22:19:48 -0800 (PST) Received: from hsinyi-z840.tpe.corp.google.com ([2401:fa00:1:10:b852:bd51:9305:4261]) by smtp.gmail.com with ESMTPSA id h5sm1225579pfk.30.2019.12.10.22.19.45 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 10 Dec 2019 22:19:48 -0800 (PST) From: Hsin-Yi Wang To: dri-devel@lists.freedesktop.org Subject: [PATCH RESEND 2/4] drm: bridge: anx7688: Add anx7688 bridge driver support. Date: Wed, 11 Dec 2019 14:19:09 +0800 Message-Id: <20191211061911.238393-3-hsinyi@chromium.org> X-Mailer: git-send-email 2.24.0.525.g8f36a354ae-goog In-Reply-To: <20191211061911.238393-1-hsinyi@chromium.org> References: <20191211061911.238393-1-hsinyi@chromium.org> MIME-Version: 1.0 X-Mailman-Approved-At: Wed, 11 Dec 2019 09:20:35 +0000 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , devicetree@vger.kernel.org, Jernej Skrabec , Nicolas Boichat , Neil Armstrong , David Airlie , Jonas Karlman , linux-kernel@vger.kernel.org, Rob Herring , Laurent Pinchart , Matthias Brugger , Enric Balletbo i Serra , Russell King Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" From: Nicolas Boichat ANX7688 is a HDMI to DP converter (as well as USB-C port controller), that has an internal microcontroller. The only reason a Linux kernel driver is necessary is to reject resolutions that require more bandwidth than what is available on the DP side. DP bandwidth and lane count are reported by the bridge via 2 registers on I2C. Signed-off-by: Nicolas Boichat Signed-off-by: Hsin-Yi Wang Tested-by: Enric Balletbo i Serra --- drivers/gpu/drm/bridge/Kconfig | 9 + drivers/gpu/drm/bridge/Makefile | 1 + drivers/gpu/drm/bridge/analogix-anx7688.c | 202 ++++++++++++++++++++++ 3 files changed, 212 insertions(+) create mode 100644 drivers/gpu/drm/bridge/analogix-anx7688.c diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig index 34362976cd6f..1f3fc6bec842 100644 --- a/drivers/gpu/drm/bridge/Kconfig +++ b/drivers/gpu/drm/bridge/Kconfig @@ -16,6 +16,15 @@ config DRM_PANEL_BRIDGE menu "Display Interface Bridges" depends on DRM && DRM_BRIDGE +config DRM_ANALOGIX_ANX7688 + tristate "Analogix ANX7688 bridge" + select DRM_KMS_HELPER + select REGMAP_I2C + ---help--- + ANX7688 is a transmitter to support DisplayPort over USB-C for + smartphone and tablets. + This driver only supports the HDMI to DP component of the chip. + config DRM_ANALOGIX_ANX78XX tristate "Analogix ANX78XX bridge" select DRM_KMS_HELPER diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile index 4934fcf5a6f8..7a1e0ec032e6 100644 --- a/drivers/gpu/drm/bridge/Makefile +++ b/drivers/gpu/drm/bridge/Makefile @@ -1,4 +1,5 @@ # SPDX-License-Identifier: GPL-2.0 +obj-$(CONFIG_DRM_ANALOGIX_ANX7688) += analogix-anx7688.o obj-$(CONFIG_DRM_ANALOGIX_ANX78XX) += analogix-anx78xx.o obj-$(CONFIG_DRM_CDNS_DSI) += cdns-dsi.o obj-$(CONFIG_DRM_DUMB_VGA_DAC) += dumb-vga-dac.o diff --git a/drivers/gpu/drm/bridge/analogix-anx7688.c b/drivers/gpu/drm/bridge/analogix-anx7688.c new file mode 100644 index 000000000000..baaed48d6201 --- /dev/null +++ b/drivers/gpu/drm/bridge/analogix-anx7688.c @@ -0,0 +1,202 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * ANX7688 HDMI->DP bridge driver + * + * Copyright 2016 Google LLC + */ + +#include +#include +#include +#include + +/* Register addresses */ +#define VENDOR_ID_REG 0x00 +#define DEVICE_ID_REG 0x02 + +#define FW_VERSION_REG 0x80 + +#define DP_BANDWIDTH_REG 0x85 +#define DP_LANE_COUNT_REG 0x86 + +#define VENDOR_ID 0x1f29 +#define DEVICE_ID 0x7688 + +/* First supported firmware version (0.85) */ +#define MINIMUM_FW_VERSION 0x0085 + +struct anx7688 { + struct drm_bridge bridge; + struct i2c_client *client; + struct regmap *regmap; + + bool filter; +}; + +static inline struct anx7688 *bridge_to_anx7688(struct drm_bridge *bridge) +{ + return container_of(bridge, struct anx7688, bridge); +} + +static bool anx7688_bridge_mode_fixup(struct drm_bridge *bridge, + const struct drm_display_mode *mode, + struct drm_display_mode *adjusted_mode) +{ + struct anx7688 *anx7688 = bridge_to_anx7688(bridge); + u8 regs[2]; + u8 dpbw, lanecount; + int totalbw, requiredbw; + int ret; + + if (!anx7688->filter) + return true; + + /* Read both regs 0x85 (bandwidth) and 0x86 (lane count). */ + ret = regmap_bulk_read(anx7688->regmap, DP_BANDWIDTH_REG, regs, 2); + if (ret < 0) { + dev_err(&anx7688->client->dev, + "Failed to read bandwidth/lane count\n"); + return false; + } + dpbw = regs[0]; + lanecount = regs[1]; + + /* Maximum 0x19 bandwidth (6.75 Gbps Turbo mode), 2 lanes */ + if (dpbw > 0x19 || lanecount > 2) { + dev_err(&anx7688->client->dev, + "Invalid bandwidth/lane count (%02x/%d)\n", + dpbw, lanecount); + return false; + } + + /* Compute available bandwidth (kHz) */ + totalbw = dpbw * lanecount * 270000 * 8 / 10; + + /* Required bandwidth (8 bpc, kHz) */ + requiredbw = mode->clock * 8 * 3; + + dev_dbg(&anx7688->client->dev, + "DP bandwidth: %d kHz (%02x/%d); mode requires %d Khz\n", + totalbw, dpbw, lanecount, requiredbw); + + if (totalbw == 0) { + dev_warn(&anx7688->client->dev, + "Bandwidth/lane count are 0, not rejecting modes\n"); + return true; + } + + return totalbw >= requiredbw; +} + +static const struct drm_bridge_funcs anx7688_bridge_funcs = { + .mode_fixup = anx7688_bridge_mode_fixup, +}; + +static const struct regmap_config anx7688_regmap_config = { + .reg_bits = 8, + .val_bits = 8, +}; + +static int anx7688_i2c_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct anx7688 *anx7688; + struct device *dev = &client->dev; + int ret; + u8 buffer[4]; + u16 vendor, device, fwversion; + + anx7688 = devm_kzalloc(dev, sizeof(*anx7688), GFP_KERNEL); + if (!anx7688) + return -ENOMEM; + +#if IS_ENABLED(CONFIG_OF) + anx7688->bridge.of_node = client->dev.of_node; +#endif + + anx7688->client = client; + i2c_set_clientdata(client, anx7688); + + anx7688->regmap = + devm_regmap_init_i2c(client, &anx7688_regmap_config); + + /* Read both vendor and device id (4 bytes). */ + ret = regmap_bulk_read(anx7688->regmap, VENDOR_ID_REG, buffer, 4); + if (ret) { + dev_err(dev, "Failed to read chip vendor/device id\n"); + return ret; + } + + vendor = (u16)buffer[1] << 8 | buffer[0]; + device = (u16)buffer[3] << 8 | buffer[2]; + if (vendor != VENDOR_ID || device != DEVICE_ID) { + dev_err(dev, "Invalid vendor/device id %04x/%04x\n", + vendor, device); + return -ENODEV; + } + + ret = regmap_bulk_read(anx7688->regmap, FW_VERSION_REG, buffer, 2); + if (ret) { + dev_err(&client->dev, "Failed to read firmware version\n"); + return ret; + } + + fwversion = (u16)buffer[0] << 8 | buffer[1]; + dev_info(dev, "ANX7688 firwmare version %02x.%02x\n", + buffer[0], buffer[1]); + + /* FW version >= 0.85 supports bandwidth/lane count registers */ + if (fwversion >= MINIMUM_FW_VERSION) { + anx7688->filter = true; + } else { + /* Warn, but not fail, for backwards compatibility. */ + dev_warn(dev, + "Old ANX7688 FW version (%02x.%02x), not filtering\n", + buffer[0], buffer[1]); + } + + anx7688->bridge.funcs = &anx7688_bridge_funcs; + drm_bridge_add(&anx7688->bridge); + + return 0; +} + +static int anx7688_i2c_remove(struct i2c_client *client) +{ + struct anx7688 *anx7688 = i2c_get_clientdata(client); + + drm_bridge_remove(&anx7688->bridge); + + return 0; +} + +static const struct i2c_device_id anx7688_id[] = { + { "anx7688", 0 }, + { /* sentinel */ } +}; + +MODULE_DEVICE_TABLE(i2c, anx7688_id); + +#if IS_ENABLED(CONFIG_OF) +static const struct of_device_id anx7688_match_table[] = { + { .compatible = "analogix,anx7688", }, + { /* sentinel */ }, +}; +MODULE_DEVICE_TABLE(of, anx7688_match_table); +#endif + +static struct i2c_driver anx7688_driver = { + .driver = { + .name = "anx7688", + .of_match_table = of_match_ptr(anx7688_match_table), + }, + .probe = anx7688_i2c_probe, + .remove = anx7688_i2c_remove, + .id_table = anx7688_id, +}; + +module_i2c_driver(anx7688_driver); + +MODULE_DESCRIPTION("ANX7688 SlimPort Transmitter driver"); +MODULE_AUTHOR("Nicolas Boichat "); +MODULE_LICENSE("GPL v2");