From patchwork Mon Dec 9 12:20:11 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: 11281655 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 8DAAB13B6 for ; Tue, 10 Dec 2019 08:40:20 +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 6BDE6206D5 for ; Tue, 10 Dec 2019 08:40:20 +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="UuqxdSbd" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6BDE6206D5 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 12B1689CB3; Tue, 10 Dec 2019 08:40:08 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mail-pf1-x442.google.com (mail-pf1-x442.google.com [IPv6:2607:f8b0:4864:20::442]) by gabe.freedesktop.org (Postfix) with ESMTPS id 586826E439 for ; Mon, 9 Dec 2019 12:20:40 +0000 (UTC) Received: by mail-pf1-x442.google.com with SMTP id d199so7149514pfd.11 for ; Mon, 09 Dec 2019 04:20:40 -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=RSrmruetV1Q5rguocJH0M9Wy7zWX1u0QVwyNeDrugN0=; b=UuqxdSbduusuMt2e/rucNTGlFMHM1xzrC2PqTwfYhfhv868xxCHhQe9BHiLMOvPUgl p50cpbnrx2wWL/0cqTA0GO3vMQLQHdyN/cFqD8OOCwBoi4GTmnWS/XOBNubxOCAQWPz2 ngMKt12erzxBO71723VUwEh9wxiMDNs3WBrb0= 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=RSrmruetV1Q5rguocJH0M9Wy7zWX1u0QVwyNeDrugN0=; b=dM1SrDI/8rgKWo1beJ4z1OXKUy3+gdoFVdOOYpHMkzu/Lyzjw6vAID+cOXO53LwMr2 oV2hSh2WuWiIM3i3RsLpWN8rkge0AJRdiAc8nScyfBQ06HCHahWv9J24VmVDcTy+UKdg deQhu8m7EENJn+v9EQtDBhmg9tGUuBtqsJpmbJt4S+rxQ2NWxIA1aIQsCfVj93nkWSZa McIdRn9N+FR0CZdy3KFJ4R1ucz9tUgD4OEJjsEVqMCW2JoSTtHH9B5YiDp/btOLx1prt tGRMDvHPM/nCNbEe4HKdSKNfvKpRu2SgBjXzmpRAADm4fE+6HA9fV2R/5blj+hF0tmNQ /ofQ== X-Gm-Message-State: APjAAAXvLSGSGfjcqs5ubB31ZqlFRTlYzKSQB76kAj7Hn/5baNhtaZ6I RULkd1139CKJV3m7zSsUaZ3soaSq6SCjoA== X-Google-Smtp-Source: APXvYqxuFnOxmzH4qGugcACPP5FsVxpy2XMw33Osu/8RcYLZ614AlQmm2wMvIatvYJOZO/oPrIUVNA== X-Received: by 2002:aa7:8d93:: with SMTP id i19mr29533222pfr.205.1575894039620; Mon, 09 Dec 2019 04:20:39 -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 p21sm26733813pfn.103.2019.12.09.04.20.37 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 09 Dec 2019 04:20:39 -0800 (PST) From: Hsin-Yi Wang To: dri-devel@lists.freedesktop.org Subject: [PATCH 2/4] drm: bridge: anx7688: Add anx7688 bridge driver support. Date: Mon, 9 Dec 2019 20:20:11 +0800 Message-Id: <20191209122013.178564-3-hsinyi@chromium.org> X-Mailer: git-send-email 2.24.0.393.g34dc348eaf-goog In-Reply-To: <20191209122013.178564-1-hsinyi@chromium.org> References: <20191209122013.178564-1-hsinyi@chromium.org> MIME-Version: 1.0 X-Mailman-Approved-At: Tue, 10 Dec 2019 08:40:04 +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: Archit Taneja , Nicolas Boichat , linux-kernel@vger.kernel.org, Matthias Brugger , Enric Balletbo i Serra , Russell King , Thierry Reding Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" From: Nicolas Boichat 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 --- drivers/gpu/drm/bridge/Kconfig | 9 + drivers/gpu/drm/bridge/Makefile | 1 + drivers/gpu/drm/bridge/analogix-anx7688.c | 203 ++++++++++++++++++++++ 3 files changed, 213 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..5a3a2251c1c5 --- /dev/null +++ b/drivers/gpu/drm/bridge/analogix-anx7688.c @@ -0,0 +1,203 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * ANX7688 HDMI->DP bridge driver + * + * Copyright 2016 Google LLC + */ + +#include +#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");