From patchwork Tue Sep 4 20:20:17 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Oskar Senft X-Patchwork-Id: 969238 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 429jzr1R37z9s4V for ; Thu, 13 Sep 2018 12:59:36 +1000 (AEST) Authentication-Results: ozlabs.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=google.com header.i=@google.com header.b="LDOvakmn"; dkim-atps=neutral Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 429jzq6xFXzF3SR for ; Thu, 13 Sep 2018 12:59:35 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=google.com header.i=@google.com header.b="LDOvakmn"; dkim-atps=neutral X-Original-To: linux-aspeed@lists.ozlabs.org Delivered-To: linux-aspeed@lists.ozlabs.org Authentication-Results: lists.ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=flex--osk.bounces.google.com (client-ip=209.85.222.74; helo=mail-ua1-f74.google.com; envelope-from=3gumowwmkdasz3vrzzrwp.nzxwty58-l30ppowt343.zawlm3.z2r@flex--osk.bounces.google.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=google.com header.i=@google.com header.b="LDOvakmn"; dkim-atps=neutral Received: from mail-ua1-f74.google.com (mail-ua1-f74.google.com [209.85.222.74]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 424dXb3fh0zF37H for ; Wed, 5 Sep 2018 06:21:45 +1000 (AEST) Received: by mail-ua1-f74.google.com with SMTP id l22-v6so2243673uak.2 for ; Tue, 04 Sep 2018 13:21:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=6LLsyucSbAmfCvWcSkJ7t1Z60f2WzW8AO8rnZEr/zrw=; b=LDOvakmn1QSMc2Zej/KkiyzURurJiRggOJbW7bzwD5TAYTon/w2gHnJioDnpaHCfhU UIMA+5LxZG10BxULAImhwjisc7gCuhMoJXktg3avSQk3fhFvfzVOOxeH0TuSLs0PE58b OgZ3vpNi5U5AnqeknRsfggxiE7r91ZJwO6bQGC+gFdzo6tsXrp/kdgNTwOtNBpI2+QeW DhdeZcIdV3dqXd+/MucKPwLS8joDJjDQ72x3Hf/JOJTMBVn/PH37Wn+myTyLGZiecJJF WQf12urtk7oWTP8Bu0z3rhVviZOqlC6yj2ixRRlhg8RqF3Gc2DTCEmTLyNnql8kotiMH 5i9A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=6LLsyucSbAmfCvWcSkJ7t1Z60f2WzW8AO8rnZEr/zrw=; b=a1MMGQDUDdnBRkc5GjepKqBvin3++wyODO9hDc6B6UjZJ6iIShyaKEu4t1tScnoGOM sv7ESzTEOH7i3GFAghMW7xgxhwJRD/aOBZD2oX5zQJ83Sbi/6LVhi49vL4UzxEaL09dH N0d7GwaNpwKggTlSAF3k6u7lkWZF+eoUlY5U8IenKLlktJuvCtEJrvbSdipQvax6hrke ras4AEXLjawkPXKJN+Xj4nE6kT2qhqtp2vwb7q5zarU6WtKg69dYp0PKN5D6wNTFrw9P Vd+ClXkX+MGJQ+NH6n8ZUtRIFmbVFwPQ1e9wDl6KQrVETpldhKsWfUk8pUSfPSahjxdL yd4Q== X-Gm-Message-State: APzg51BL9+TN6D8lFieMpq7BLrEOS04YZ49i08hS7hIowOoaRUXg0qQZ +JmtxcBKR4xfL2aNvU9I26VkHJA= X-Google-Smtp-Source: ANB0VdYeMyDAzMF1Vb0TTuof4I5QgDn6CQDMTE63svBhbpQ08X3SUaaPJ0mNYYl1BS06+wVJbVBEb8Y= X-Received: by 2002:ab0:555d:: with SMTP id u29-v6mr14138054uaa.55.1536092442774; Tue, 04 Sep 2018 13:20:42 -0700 (PDT) Date: Tue, 4 Sep 2018 16:20:17 -0400 In-Reply-To: <20180904202018.198707-1-osk@google.com> Message-Id: <20180904202018.198707-2-osk@google.com> Mime-Version: 1.0 References: <20180904202018.198707-1-osk@google.com> X-Mailer: git-send-email 2.19.0.rc1.350.ge57e33dbd1-goog Subject: [PATCH 1/2] misc: aspeed: Add Aspeed UART routing control driver. From: Oskar Senft To: andrew@aj.id.au X-Mailman-Approved-At: Thu, 13 Sep 2018 12:59:23 +1000 X-BeenThere: linux-aspeed@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux ASPEED SoC development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linus.walleij@linaro.org, Oskar Senft , linux-aspeed@lists.ozlabs.org Errors-To: linux-aspeed-bounces+incoming=patchwork.ozlabs.org@lists.ozlabs.org Sender: "Linux-aspeed" This driver adds sysfs files that allow the BMC userspace to configure how UARTs and physical serial I/O ports are routed. Tested: Checked correct behavior (both read & write) on TYAN S7106 board by manually changing routing settings and confirming that bits flow as expected. Tested for UART1 and UART3 as this board doesn't have the other UARTs wired up in a testable way. Signed-off-by: Oskar Senft --- .../stable/sysfs-driver-aspeed-uart-routing | 14 + .../misc-devices/aspeed-uart-routing.txt | 49 +++ drivers/misc/Kconfig | 10 + drivers/misc/Makefile | 1 + drivers/misc/aspeed-uart-routing.c | 384 ++++++++++++++++++ 5 files changed, 458 insertions(+) create mode 100644 Documentation/ABI/stable/sysfs-driver-aspeed-uart-routing create mode 100644 Documentation/misc-devices/aspeed-uart-routing.txt create mode 100644 drivers/misc/aspeed-uart-routing.c diff --git a/Documentation/ABI/stable/sysfs-driver-aspeed-uart-routing b/Documentation/ABI/stable/sysfs-driver-aspeed-uart-routing new file mode 100644 index 000000000000..5068737d9c12 --- /dev/null +++ b/Documentation/ABI/stable/sysfs-driver-aspeed-uart-routing @@ -0,0 +1,14 @@ +What: /sys/bus/platform/drivers/aspeed-uart-routing/*/io* +Date: August 2018 +Contact: Oskar Senft +Description: Configures the input source for the specific physical + serial I/O port. +Users: OpenBMC. Proposed changes should be mailed to + openbmc@lists.ozlabs.org + +What: /sys/bus/platform/drivers/aspeed-uart-routing/*/uart* +Date: August 2018 +Contact: Oskar Senft +Description: Configures the input source for the specific UART. +Users: OpenBMC. Proposed changes should be mailed to + openbmc@lists.ozlabs.org diff --git a/Documentation/misc-devices/aspeed-uart-routing.txt b/Documentation/misc-devices/aspeed-uart-routing.txt new file mode 100644 index 000000000000..afaf17cb7eda --- /dev/null +++ b/Documentation/misc-devices/aspeed-uart-routing.txt @@ -0,0 +1,49 @@ +Kernel driver aspeed-uart-routing +================================= + +Supported chips: +ASPEED AST2500 + +Author: +Google LLC + +Description +----------- + +The Aspeed AST2500 allows to dynamically route the inputs for the built-in +UARTS and physical serial I/O ports. + +This allows, for example, to connect the output of UART to another UART. +This can be used to enable host<->BMC communication via UARTs, e.g. to allow +access to the host's serial console. + +This driver is for the BMC side. The sysfs files allow the BMC userspace +which owns the system configuration policy, to configure how UARTs and +physical serial I/O ports are routed. + +The driver provides the following files in sysfs: +uart1 Configure the input signal to UART1. +uart2 Configure the input signal to UART2. +uart3 Configure the input signal to UART3. +uart4 Configure the input signal to UART4. +uart5 Configure the input signal to UART5. +io1 Configure the input signal to physical serial port 1. +io2 Configure the input signal to physical serial port 2. +io3 Configure the input signal to physical serial port 3. +io4 Configure the input signal to physical serial port 4. +io5 Configure the input signal to physical serial port 5. + +When read, each file shows the list of available options with the currently +selected option marked by square brackets "[]". The list of available options +depends on the selected file. + +Example: +$ cat /sys/bus/platform/drivers/aspeed-uart-routing/*.uart_routing/uart1 +[io1] io2 io3 io4 uart2 uart3 uart4 io6 + +In this case, UART1 gets its input signal from IO1 (physical serial port 1). + +$ echo -n "uart3" \ + >/sys/bus/platform/drivers/aspeed-uart-routing/*.uart_routing/uart1 +$ cat /sys/bus/platform/drivers/aspeed-uart-routing/*.uart_routing/uart1 +io1 io2 io3 io4 uart2 [uart3] uart4 io6 diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig index 3726eacdf65d..89d42cd6b790 100644 --- a/drivers/misc/Kconfig +++ b/drivers/misc/Kconfig @@ -501,6 +501,16 @@ config ASPEED_LPC_SNOOP allows the BMC to listen on and save the data written by the host to an arbitrary LPC I/O port. +config ASPEED_UART_ROUTING + tristate "Aspeed ast2500 UART routing control" + depends on (ARCH_ASPEED || COMPILE_TEST) + help + Provides a driver to configure UART routing on Aspeed BMC platforms + at runtime through sysfs. This allows, for example, to connect the + output of UART to another UART. This can be used to enable host<->BMC + communication via UARTs, e.g. to allow access to the host's serial + console. + config PCI_ENDPOINT_TEST depends on PCI select CRC32 diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile index af22bbc3d00c..9705182b317f 100644 --- a/drivers/misc/Makefile +++ b/drivers/misc/Makefile @@ -55,6 +55,7 @@ obj-$(CONFIG_VEXPRESS_SYSCFG) += vexpress-syscfg.o obj-$(CONFIG_CXL_BASE) += cxl/ obj-$(CONFIG_ASPEED_LPC_CTRL) += aspeed-lpc-ctrl.o obj-$(CONFIG_ASPEED_LPC_SNOOP) += aspeed-lpc-snoop.o +obj-$(CONFIG_ASPEED_UART_ROUTING) += aspeed-uart-routing.o obj-$(CONFIG_PCI_ENDPOINT_TEST) += pci_endpoint_test.o obj-$(CONFIG_OCXL) += ocxl/ obj-$(CONFIG_MISC_RTSX) += cardreader/ diff --git a/drivers/misc/aspeed-uart-routing.c b/drivers/misc/aspeed-uart-routing.c new file mode 100644 index 000000000000..381bac19e4af --- /dev/null +++ b/drivers/misc/aspeed-uart-routing.c @@ -0,0 +1,384 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * UART Routing driver for Aspeed AST2500 + * + * Copyright (c) 2018 Google LLC + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * version 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ +#include +#include +#include +#include + +/* The Aspeed AST2500 allows to dynamically route the inputs for the built-in + * UARTS and physical serial I/O ports. + * + * This allows, for example, to connect the output of UART to another UART. + * This can be used to enable host<->BMC communication via UARTs, e.g. to allow + * access to the host's serial console. + * + * This driver is for the BMC side. The sysfs files allow the BMC userspace + * which owns the system configuration policy, to configure how UARTs and + * physical serial I/O ports are routed. + */ + +#define ASPEED_HICRA_IO1 "io1" +#define ASPEED_HICRA_IO2 "io2" +#define ASPEED_HICRA_IO3 "io3" +#define ASPEED_HICRA_IO4 "io4" +#define ASPEED_HICRA_IO5 "io5" +#define ASPEED_HICRA_IO6 "io6" +#define ASPEED_HICRA_UART1 "uart1" +#define ASPEED_HICRA_UART2 "uart2" +#define ASPEED_HICRA_UART3 "uart3" +#define ASPEED_HICRA_UART4 "uart4" +#define ASPEED_HICRA_UART5 "uart5" + +struct aspeed_uart_routing { + struct device *dev; + void __iomem *regs; + spinlock_t lock; +}; + +struct aspeed_uart_routing_selector { + struct device_attribute dev_attr; + int shift; + int mask; + const char * const options[]; +}; + +#define to_routing_selector(_dev_attr) \ + container_of(_dev_attr, struct aspeed_uart_routing_selector, dev_attr) + + +static ssize_t aspeed_uart_routing_show(struct device *dev, + struct device_attribute *attr, + char *buf); + +static ssize_t aspeed_uart_routing_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count); + +#define ROUTING_ATTR(_name) { \ + .attr = {.name = _name, \ + .mode = VERIFY_OCTAL_PERMISSIONS(0644) }, \ + .show = aspeed_uart_routing_show, \ + .store = aspeed_uart_routing_store, \ +} + +static struct aspeed_uart_routing_selector uart5_sel = { + .dev_attr = ROUTING_ATTR(ASPEED_HICRA_UART5), + .shift = 28, + .mask = 0xf, + .options = { + ASPEED_HICRA_IO5, // 0 + ASPEED_HICRA_IO1, // 1 + ASPEED_HICRA_IO2, // 2 + ASPEED_HICRA_IO3, // 3 + ASPEED_HICRA_IO4, // 4 + ASPEED_HICRA_UART1, // 5 + ASPEED_HICRA_UART2, // 6 + ASPEED_HICRA_UART3, // 7 + ASPEED_HICRA_UART4, // 8 + ASPEED_HICRA_IO6, // 9 + NULL, // NULL termination + }, +}; + +static struct aspeed_uart_routing_selector uart4_sel = { + .dev_attr = ROUTING_ATTR(ASPEED_HICRA_UART4), + .shift = 25, + .mask = 0x7, + .options = { + ASPEED_HICRA_IO4, // 0 + ASPEED_HICRA_IO1, // 1 + ASPEED_HICRA_IO2, // 2 + ASPEED_HICRA_IO3, // 3 + ASPEED_HICRA_UART1, // 4 + ASPEED_HICRA_UART2, // 5 + ASPEED_HICRA_UART3, // 6 + ASPEED_HICRA_IO6, // 7 + NULL, // NULL termination + }, +}; + +static struct aspeed_uart_routing_selector uart3_sel = { + .dev_attr = ROUTING_ATTR(ASPEED_HICRA_UART3), + .shift = 22, + .mask = 0x7, + .options = { + ASPEED_HICRA_IO3, // 0 + ASPEED_HICRA_IO4, // 1 + ASPEED_HICRA_IO1, // 2 + ASPEED_HICRA_IO2, // 3 + ASPEED_HICRA_UART4, // 4 + ASPEED_HICRA_UART1, // 5 + ASPEED_HICRA_UART2, // 6 + ASPEED_HICRA_IO6, // 7 + NULL, // NULL termination + }, +}; + +static struct aspeed_uart_routing_selector uart2_sel = { + .dev_attr = ROUTING_ATTR(ASPEED_HICRA_UART2), + .shift = 19, + .mask = 0x7, + .options = { + ASPEED_HICRA_IO2, // 0 + ASPEED_HICRA_IO3, // 1 + ASPEED_HICRA_IO4, // 2 + ASPEED_HICRA_IO1, // 3 + ASPEED_HICRA_UART3, // 4 + ASPEED_HICRA_UART4, // 5 + ASPEED_HICRA_UART1, // 6 + ASPEED_HICRA_IO6, // 7 + NULL, // NULL termination + }, +}; + +static struct aspeed_uart_routing_selector uart1_sel = { + .dev_attr = ROUTING_ATTR(ASPEED_HICRA_UART1), + .shift = 16, + .mask = 0x7, + .options = { + ASPEED_HICRA_IO1, // 0 + ASPEED_HICRA_IO2, // 1 + ASPEED_HICRA_IO3, // 2 + ASPEED_HICRA_IO4, // 3 + ASPEED_HICRA_UART2, // 4 + ASPEED_HICRA_UART3, // 5 + ASPEED_HICRA_UART4, // 6 + ASPEED_HICRA_IO6, // 7 + NULL, // NULL termination + }, +}; + +static struct aspeed_uart_routing_selector io5_sel = { + .dev_attr = ROUTING_ATTR(ASPEED_HICRA_IO5), + .shift = 12, + .mask = 0x7, + .options = { + ASPEED_HICRA_UART5, // 0 + ASPEED_HICRA_UART1, // 1 + ASPEED_HICRA_UART2, // 2 + ASPEED_HICRA_UART3, // 3 + ASPEED_HICRA_UART4, // 4 + ASPEED_HICRA_IO1, // 5 + ASPEED_HICRA_IO3, // 6 + ASPEED_HICRA_IO6, // 7 + NULL, // NULL termination + }, +}; + +static struct aspeed_uart_routing_selector io4_sel = { + .dev_attr = ROUTING_ATTR(ASPEED_HICRA_IO4), + .shift = 9, + .mask = 0x7, + .options = { + ASPEED_HICRA_UART4, // 0 + ASPEED_HICRA_UART5, // 1 + ASPEED_HICRA_UART1, // 2 + ASPEED_HICRA_UART2, // 3 + ASPEED_HICRA_UART3, // 4 + ASPEED_HICRA_IO1, // 5 + ASPEED_HICRA_IO2, // 6 + ASPEED_HICRA_IO6, // 7 + NULL, // NULL termination + }, +}; + +static struct aspeed_uart_routing_selector io3_sel = { + .dev_attr = ROUTING_ATTR(ASPEED_HICRA_IO3), + .shift = 6, + .mask = 0x7, + .options = { + ASPEED_HICRA_UART3, // 0 + ASPEED_HICRA_UART4, // 1 + ASPEED_HICRA_UART5, // 2 + ASPEED_HICRA_UART1, // 3 + ASPEED_HICRA_UART2, // 4 + ASPEED_HICRA_IO1, // 5 + ASPEED_HICRA_IO2, // 6 + ASPEED_HICRA_IO6, // 7 + NULL, // NULL termination + }, +}; + +static struct aspeed_uart_routing_selector io2_sel = { + .dev_attr = ROUTING_ATTR(ASPEED_HICRA_IO2), + .shift = 3, + .mask = 0x7, + .options = { + ASPEED_HICRA_UART2, // 0 + ASPEED_HICRA_UART3, // 1 + ASPEED_HICRA_UART4, // 2 + ASPEED_HICRA_UART5, // 3 + ASPEED_HICRA_UART1, // 4 + ASPEED_HICRA_IO3, // 5 + ASPEED_HICRA_IO4, // 6 + ASPEED_HICRA_IO6, // 7 + NULL, // NULL termination + }, +}; + +static struct aspeed_uart_routing_selector io1_sel = { + .dev_attr = ROUTING_ATTR(ASPEED_HICRA_IO1), + .shift = 0, + .mask = 0x7, + .options = { + ASPEED_HICRA_UART1, // 0 + ASPEED_HICRA_UART2, // 1 + ASPEED_HICRA_UART3, // 2 + ASPEED_HICRA_UART4, // 3 + ASPEED_HICRA_UART5, // 4 + ASPEED_HICRA_IO3, // 5 + ASPEED_HICRA_IO4, // 6 + ASPEED_HICRA_IO6, // 7 + NULL, // NULL termination + }, +}; + + +static struct attribute *aspeed_uart_routing_attrs[] = { + &uart1_sel.dev_attr.attr, + &uart2_sel.dev_attr.attr, + &uart3_sel.dev_attr.attr, + &uart4_sel.dev_attr.attr, + &uart5_sel.dev_attr.attr, + &io1_sel.dev_attr.attr, + &io2_sel.dev_attr.attr, + &io3_sel.dev_attr.attr, + &io4_sel.dev_attr.attr, + &io5_sel.dev_attr.attr, + NULL, +}; + +static const struct attribute_group aspeed_uart_routing_attr_group = { + .attrs = aspeed_uart_routing_attrs, +}; + +static ssize_t aspeed_uart_routing_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct aspeed_uart_routing *uart_routing = dev_get_drvdata(dev); + struct aspeed_uart_routing_selector *sel = to_routing_selector(attr); + int val, pos, len; + + val = (readl(uart_routing->regs) >> sel->shift) & sel->mask; + + len = 0; + for (pos = 0; sel->options[pos] != NULL; ++pos) { + if (pos == val) { + len += snprintf(buf + len, PAGE_SIZE - 1 - len, + "[%s] ", sel->options[pos]); + } else { + len += snprintf(buf + len, PAGE_SIZE - 1 - len, + "%s ", sel->options[pos]); + } + } + + if (val >= pos) { + len += snprintf(buf + len, PAGE_SIZE - 1 - len, + "[unknown(%d)]", val); + } + + len += snprintf(buf + len, PAGE_SIZE - 1 - len, "\n"); + + return len; +} + +static ssize_t aspeed_uart_routing_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct aspeed_uart_routing *uart_routing = dev_get_drvdata(dev); + struct aspeed_uart_routing_selector *sel = to_routing_selector(attr); + int val; + u32 reg; + + val = match_string(sel->options, -1, buf); + if (val < 0) { + dev_err(dev, "invalid value \"%s\"\n", buf); + return -EINVAL; + } + + spin_lock(&uart_routing->lock); + reg = readl(uart_routing->regs); + // Zero out existing value in specified bits. + reg &= ~(sel->mask << sel->shift); + // Set new value in specified bits. + reg |= (val & sel->mask) << sel->shift; + writel(reg, uart_routing->regs); + spin_unlock(&uart_routing->lock); + + return count; +} + +static int aspeed_uart_routing_probe(struct platform_device *pdev) +{ + struct aspeed_uart_routing *uart_routing; + struct resource *res; + int rc; + + uart_routing = devm_kzalloc(&pdev->dev, + sizeof(*uart_routing), + GFP_KERNEL); + if (!uart_routing) + return -ENOMEM; + + spin_lock_init(&uart_routing->lock); + uart_routing->dev = &pdev->dev; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + uart_routing->regs = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(uart_routing->regs)) + return PTR_ERR(uart_routing->regs); + + rc = sysfs_create_group(&uart_routing->dev->kobj, + &aspeed_uart_routing_attr_group); + if (rc < 0) + return rc; + + platform_set_drvdata(pdev, uart_routing); + + return 0; +} + +static int aspeed_uart_routing_remove(struct platform_device *pdev) +{ + struct aspeed_uart_routing *uart_routing = platform_get_drvdata(pdev); + + sysfs_remove_group(&uart_routing->dev->kobj, + &aspeed_uart_routing_attr_group); + + return 0; +} + +static const struct of_device_id aspeed_uart_routing_table[] = { + { .compatible = "aspeed,ast2500-uart-routing" }, + { }, +}; + +static struct platform_driver aspeed_uart_routing_driver = { + .driver = { + .name = "aspeed-uart-routing", + .of_match_table = aspeed_uart_routing_table, + }, + .probe = aspeed_uart_routing_probe, + .remove = aspeed_uart_routing_remove, +}; + +module_platform_driver(aspeed_uart_routing_driver); + +MODULE_AUTHOR("Oskar Senft "); +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("Driver to configure Aspeed UART routing");