From mboxrd@z Thu Jan 1 00:00:00 1970 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 4F7CCC4332F for ; Tue, 8 Feb 2022 01:06:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240554AbiBHBFX (ORCPT ); Mon, 7 Feb 2022 20:05:23 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39912 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S245677AbiBGXWA (ORCPT ); Mon, 7 Feb 2022 18:22:00 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id F0F7FC061A73 for ; Mon, 7 Feb 2022 15:21:59 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1644276119; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=Iw9wt34aXKvuMxoYZcgwMJfoVHqXFAcM6CtavfIfEfU=; b=Vs6fQWCXqaVAn1c7CjeXE2ytMVEEkb0HcJPuOpUrQCcvGQAhUpLTL7c4/KWKsuGlAd3SuD O0UspkhwZLVHpW8FaXa72C4j2bjCXZ7gyp8jPUdwWQciC2vYpPg7nSER+cS/JKI5hAFLBT Xtv7jPHUOZsmEticCCGVzPx+lIMLZxQ= Received: from mail-qt1-f200.google.com (mail-qt1-f200.google.com [209.85.160.200]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-207-b3cga8fCMD2DEMA8_Rvc0w-1; Mon, 07 Feb 2022 18:21:57 -0500 X-MC-Unique: b3cga8fCMD2DEMA8_Rvc0w-1 Received: by mail-qt1-f200.google.com with SMTP id c10-20020ac81e8a000000b002d7ea4837ddso12230787qtm.13 for ; Mon, 07 Feb 2022 15:21:57 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=Iw9wt34aXKvuMxoYZcgwMJfoVHqXFAcM6CtavfIfEfU=; b=1TKbHOnqL9MRAqII9cnfZ+PCRJ9i37A8JCBOqk1oMQaUIa7GKjcJUFk053PZLA/7gr J734TebTrnvu5tLKTxhyWrKSJf7u09bCI6Oe5P1ijBywicNMevliSzF/62vSvWlcEro0 qi+xzxg5yR8UMAfcDVl8Au2qAUt84m/cSXrPchAnmg0vJld5rTypnGEveN7Kgozm4rvx gdQBFktce3NNoxtUVpfsCjJm3yVg+tyxKYbblfD80aB9DqeFRU4a/CPY9r9Fllz8Bf+k rlhFrdPwXdQPp3RhEsI/xAKXY1hEMi83H7Vl5KqQ+qJONOXbjhDIn0mNd4EvpOdGWgUt p0tg== X-Gm-Message-State: AOAM532g/4r6DTS/X4NTX9BTTC+Bgc9mjUYdss/AQzARrfGfFT7QRLkT R0FzCgirweXnnGWJ6BckycaQ9DRbtaoDoZ+4VQQMlQX3Hm7/cu54yh2S6h+NADhiMUZtpCiNZGd thxiFfGk0M6j1F+0iacFrfxWuU1t40yv2Jha9At9je4lM0kDNOPiw22n0UVjVpaZOwk5ghwMjg9 x4 X-Received: by 2002:ad4:5ce7:: with SMTP id iv7mr1363056qvb.121.1644276116341; Mon, 07 Feb 2022 15:21:56 -0800 (PST) X-Google-Smtp-Source: ABdhPJw1NtXQcsm5FW3EBilz/ZfT3Cvi3lIDzaSf3isXw3sfYe4piCqut0wV1cRBs/K/pJ1jR71oUg== X-Received: by 2002:ad4:5ce7:: with SMTP id iv7mr1363030qvb.121.1644276116076; Mon, 07 Feb 2022 15:21:56 -0800 (PST) Received: from fedora.hitronhub.home (modemcable200.11-22-96.mc.videotron.ca. [96.22.11.200]) by smtp.gmail.com with ESMTPSA id y2sm5906567qke.33.2022.02.07.15.21.54 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 07 Feb 2022 15:21:55 -0800 (PST) From: Adrien Thierry To: linux-serial@vger.kernel.org, linux-rpi-kernel@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Cc: Adrien Thierry , Jeremy Linton , Greg Kroah-Hartman , Jiri Slaby , Nicolas Saenz Julienne , Florian Fainelli , Ray Jui , Scott Branden , bcm-kernel-feedback-list@broadcom.com Subject: [PATCH v3] serial: 8250_bcm2835aux: Add ACPI support Date: Mon, 7 Feb 2022 18:21:29 -0500 Message-Id: <20220207232129.402882-1-athierry@redhat.com> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=athierry@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset="US-ASCII" Precedence: bulk List-ID: X-Mailing-List: linux-serial@vger.kernel.org Add ACPI support to 8250_bcm2835aux driver. This makes it possible to use the miniuart on the Raspberry Pi with the tianocore/edk2 UEFI firmware. Signed-off-by: Adrien Thierry --- V1 -> V2: Refactored code to remove unnecessary conditional paths and intermediate variables V2 -> V3: Cleaned up coding style and addressed review comments drivers/tty/serial/8250/8250_bcm2835aux.c | 52 ++++++++++++++++++++--- 1 file changed, 46 insertions(+), 6 deletions(-) diff --git a/drivers/tty/serial/8250/8250_bcm2835aux.c b/drivers/tty/serial/8250/8250_bcm2835aux.c index fd95860cd661..2a1226a78a0c 100644 --- a/drivers/tty/serial/8250/8250_bcm2835aux.c +++ b/drivers/tty/serial/8250/8250_bcm2835aux.c @@ -17,6 +17,7 @@ #include #include #include +#include #include "8250.h" @@ -44,6 +45,10 @@ struct bcm2835aux_data { u32 cntl; }; +struct bcm2835_aux_serial_driver_data { + resource_size_t offset; +}; + static void bcm2835aux_rs485_start_tx(struct uart_8250_port *up) { if (!(up->port.rs485.flags & SER_RS485_RX_DURING_TX)) { @@ -80,9 +85,12 @@ static void bcm2835aux_rs485_stop_tx(struct uart_8250_port *up) static int bcm2835aux_serial_probe(struct platform_device *pdev) { + const struct bcm2835_aux_serial_driver_data *bcm_data; struct uart_8250_port up = { }; struct bcm2835aux_data *data; + resource_size_t offset = 0; struct resource *res; + unsigned int uartclk; int ret; /* allocate the custom structure */ @@ -109,9 +117,7 @@ static int bcm2835aux_serial_probe(struct platform_device *pdev) platform_set_drvdata(pdev, data); /* get the clock - this also enables the HW */ - data->clk = devm_clk_get(&pdev->dev, NULL); - if (IS_ERR(data->clk)) - return dev_err_probe(&pdev->dev, PTR_ERR(data->clk), "could not get clk\n"); + data->clk = devm_clk_get_optional(&pdev->dev, NULL); /* get the interrupt */ ret = platform_get_irq(pdev, 0); @@ -125,8 +131,24 @@ static int bcm2835aux_serial_probe(struct platform_device *pdev) dev_err(&pdev->dev, "memory resource not found"); return -EINVAL; } - up.port.mapbase = res->start; - up.port.mapsize = resource_size(res); + + bcm_data = device_get_match_data(&pdev->dev); + + /* Some UEFI implementations (e.g. tianocore/edk2 for the Raspberry Pi) + * describe the miniuart with a base address that encompasses the auxiliary + * registers shared between the miniuart and spi. + * + * This is due to historical reasons, see discussion here : + * https://edk2.groups.io/g/devel/topic/87501357#84349 + * + * We need to add the offset between the miniuart and auxiliary + * registers to get the real miniuart base address. + */ + if (bcm_data) + offset = bcm_data->offset; + + up.port.mapbase = res->start + offset; + up.port.mapsize = resource_size(res) - offset; /* Check for a fixed line number */ ret = of_alias_get_id(pdev->dev.of_node, "serial"); @@ -141,12 +163,19 @@ static int bcm2835aux_serial_probe(struct platform_device *pdev) return ret; } + uartclk = clk_get_rate(data->clk); + if (!uartclk) { + ret = device_property_read_u32(&pdev->dev, "clock-frequency", &uartclk); + if (ret) + return dev_err_probe(&pdev->dev, ret, "could not get clk rate\n"); + } + /* the HW-clock divider for bcm2835aux is 8, * but 8250 expects a divider of 16, * so we have to multiply the actual clock by 2 * to get identical baudrates. */ - up.port.uartclk = clk_get_rate(data->clk) * 2; + up.port.uartclk = uartclk * 2; /* register the port */ ret = serial8250_register_8250_port(&up); @@ -173,16 +202,27 @@ static int bcm2835aux_serial_remove(struct platform_device *pdev) return 0; } +static const struct bcm2835_aux_serial_driver_data bcm2835_acpi_data = { + .offset = 0x40, +}; + static const struct of_device_id bcm2835aux_serial_match[] = { { .compatible = "brcm,bcm2835-aux-uart" }, { }, }; MODULE_DEVICE_TABLE(of, bcm2835aux_serial_match); +static const struct acpi_device_id bcm2835aux_serial_acpi_match[] = { + { "BCM2836", (kernel_ulong_t)&bcm2835_acpi_data }, + { } +}; +MODULE_DEVICE_TABLE(acpi, bcm2835aux_serial_acpi_match); + static struct platform_driver bcm2835aux_serial_driver = { .driver = { .name = "bcm2835-aux-uart", .of_match_table = bcm2835aux_serial_match, + .acpi_match_table = bcm2835aux_serial_acpi_match, }, .probe = bcm2835aux_serial_probe, .remove = bcm2835aux_serial_remove, base-commit: 2ade8eef993c37a2a43e51a9b1f6c25509a2acce -- 2.34.1