From patchwork Mon Sep 21 14:02:42 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tomeu Vizoso X-Patchwork-Id: 7231331 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 58D719F30C for ; Mon, 21 Sep 2015 14:06:22 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 51EE82077A for ; Mon, 21 Sep 2015 14:06:21 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 49A742068E for ; Mon, 21 Sep 2015 14:06:19 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1Ze1hH-00029X-3p; Mon, 21 Sep 2015 14:03:59 +0000 Received: from mail-wi0-x22a.google.com ([2a00:1450:400c:c05::22a]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1Ze1hD-00021d-G4 for linux-arm-kernel@lists.infradead.org; Mon, 21 Sep 2015 14:03:56 +0000 Received: by wicfx3 with SMTP id fx3so147584872wic.1 for ; Mon, 21 Sep 2015 07:03:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:from:to:cc:subject:date:message-id:in-reply-to:references; bh=RH8TGigZQwpTZXoImqobcU/CsLEb3VNoko75Bkuathw=; b=tMTUDFGM+nBRGBbqL+Epfih2GGAOghlymMn8rzs5FAsjvi6frRl4vxMBmQKuPIJ5oF tdSuHjyZ6kaxM5OSgK2+HwRhVULVoJ/ySxRCfw4nQd4c4Po5wJJOL9RFtvwA7oGATL3e glYTxXdacZPVpm+CCx/wdVefEE7aeDGC6d8JIMDIKJ0Lty9+z9W5Y6l9GoppqPFIZRPE 35CZQ7wh2cVG+4lxDEVOt+Dnc4n/mHxUDlCT7f3lybn88o1s7+nlvXcXh0oXF3gs1AyX eDKXqKE7j4emntBbJA76d/gd6fYCgkQw7hdfAVDeo1EIiaJAnREtp09aAk4V9EGrjszs l2Nw== X-Received: by 10.194.220.227 with SMTP id pz3mr1904427wjc.26.1442844213819; Mon, 21 Sep 2015 07:03:33 -0700 (PDT) Received: from cizrna.lan ([109.72.12.69]) by smtp.gmail.com with ESMTPSA id gk9sm13687031wib.9.2015.09.21.07.03.31 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 21 Sep 2015 07:03:32 -0700 (PDT) From: Tomeu Vizoso To: linux-kernel@vger.kernel.org Subject: [PATCH v6 02/22] ARM: amba: Move reading of periphid to amba_match() Date: Mon, 21 Sep 2015 16:02:42 +0200 Message-Id: <1442844182-27787-3-git-send-email-tomeu.vizoso@collabora.com> X-Mailer: git-send-email 2.4.3 In-Reply-To: <1442844182-27787-1-git-send-email-tomeu.vizoso@collabora.com> References: <1442844182-27787-1-git-send-email-tomeu.vizoso@collabora.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20150921_070355_739412_28F3B18A X-CRM114-Status: GOOD ( 23.89 ) X-Spam-Score: -2.6 (--) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Tomeu Vizoso , devicetree@vger.kernel.org, linux-acpi@vger.kernel.org, Arnd Bergmann , Stephen Warren , Greg Kroah-Hartman , Linus Walleij , Dmitry Torokhov , "Rafael J. Wysocki" , Rob Herring , Javier Martinez Canillas , Mark Brown , Thierry Reding , Alan Stern , linux-arm-kernel@lists.infradead.org MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_MED,RP_MATCHES_RCVD,T_DKIM_INVALID,UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Reading the periphid when the Primecell device is registered means that the apb pclk must be available by then or the device won't be registered at all. By reading the periphid in amba_match() we can return -EPROBE_DEFER if the apb pclk isn't there yet and the device will be retried later. Signed-off-by: Tomeu Vizoso --- Changes in v6: - Drop bus_type.pre_probe and read the periphid in match() instead as suggested by Alan Stern. Changes in v4: - Added bus.pre_probe callback so the probes of Primecell devices can be deferred if their device IDs cannot be yet read because of the clock driver not having probed when they are registered. Maybe this goes overboard and the matching information should be in the DT if there is one. drivers/amba/bus.c | 88 ++++++++++++++++++++++++++++-------------------------- 1 file changed, 46 insertions(+), 42 deletions(-) diff --git a/drivers/amba/bus.c b/drivers/amba/bus.c index f0099360039e..72ebf9b1c715 100644 --- a/drivers/amba/bus.c +++ b/drivers/amba/bus.c @@ -24,6 +24,8 @@ #define to_amba_driver(d) container_of(d, struct amba_driver, drv) +static int read_periphid(struct amba_device *d, unsigned int *periphid); + static const struct amba_id * amba_lookup(const struct amba_id *table, struct amba_device *dev) { @@ -43,11 +45,22 @@ static int amba_match(struct device *dev, struct device_driver *drv) { struct amba_device *pcdev = to_amba_device(dev); struct amba_driver *pcdrv = to_amba_driver(drv); + int ret; /* When driver_override is set, only bind to the matching driver */ if (pcdev->driver_override) return !strcmp(pcdev->driver_override, drv->name); + if (!pcdev->periphid) { + ret = read_periphid(pcdev, &pcdev->periphid); + if (ret) { + if (ret != -EPROBE_DEFER) + dev_err(dev, "Failed to read periphid: %d", + ret); + return ret; + } + } + return amba_lookup(pcdrv->id_table, pcdev) != NULL; } @@ -336,44 +349,22 @@ static void amba_device_release(struct device *dev) kfree(d); } -/** - * amba_device_add - add a previously allocated AMBA device structure - * @dev: AMBA device allocated by amba_device_alloc - * @parent: resource parent for this devices resources - * - * Claim the resource, and read the device cell ID if not already - * initialized. Register the AMBA device with the Linux device - * manager. - */ -int amba_device_add(struct amba_device *dev, struct resource *parent) +static int read_periphid(struct amba_device *d, unsigned int *periphid) { u32 size; void __iomem *tmp; - int i, ret; - - WARN_ON(dev->irq[0] == (unsigned int)-1); - WARN_ON(dev->irq[1] == (unsigned int)-1); - - ret = request_resource(parent, &dev->res); - if (ret) - goto err_out; - - /* Hard-coded primecell ID instead of plug-n-play */ - if (dev->periphid != 0) - goto skip_probe; + int i, ret = 0; /* * Dynamically calculate the size of the resource * and use this for iomap */ - size = resource_size(&dev->res); - tmp = ioremap(dev->res.start, size); - if (!tmp) { - ret = -ENOMEM; - goto err_release; - } + size = resource_size(&d->res); + tmp = ioremap(d->res.start, size); + if (!tmp) + return -ENOMEM; - ret = amba_get_enable_pclk(dev); + ret = amba_get_enable_pclk(d); if (ret == 0) { u32 pid, cid; @@ -388,37 +379,50 @@ int amba_device_add(struct amba_device *dev, struct resource *parent) cid |= (readl(tmp + size - 0x10 + 4 * i) & 255) << (i * 8); - amba_put_disable_pclk(dev); + amba_put_disable_pclk(d); if (cid == AMBA_CID || cid == CORESIGHT_CID) - dev->periphid = pid; + *periphid = pid; - if (!dev->periphid) + if (!*periphid) ret = -ENODEV; } iounmap(tmp); + return ret; +} + +/** + * amba_device_add - add a previously allocated AMBA device structure + * @dev: AMBA device allocated by amba_device_alloc + * @parent: resource parent for this devices resources + * + * Claim the resource, and register the AMBA device with the Linux device + * manager. + */ +int amba_device_add(struct amba_device *dev, struct resource *parent) +{ + int ret; + + WARN_ON(dev->irq[0] == (unsigned int)-1); + WARN_ON(dev->irq[1] == (unsigned int)-1); + + ret = request_resource(parent, &dev->res); if (ret) - goto err_release; + return ret; - skip_probe: ret = device_add(&dev->dev); if (ret) - goto err_release; + return ret; if (dev->irq[0]) ret = device_create_file(&dev->dev, &dev_attr_irq0); if (ret == 0 && dev->irq[1]) ret = device_create_file(&dev->dev, &dev_attr_irq1); - if (ret == 0) - return ret; - - device_unregister(&dev->dev); + if (ret) + device_unregister(&dev->dev); - err_release: - release_resource(&dev->res); - err_out: return ret; } EXPORT_SYMBOL_GPL(amba_device_add);