From patchwork Tue May 13 11:48:36 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pawel Moll X-Patchwork-Id: 4166931 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 7A317BFF02 for ; Tue, 13 May 2014 11:51:39 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 9C49020304 for ; Tue, 13 May 2014 11:51:38 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 7EC5F20266 for ; Tue, 13 May 2014 11:51:37 +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 1WkBCq-00028b-0c; Tue, 13 May 2014 11:49:12 +0000 Received: from fw-tnat.austin.arm.com ([217.140.110.23] helo=collaborate-mta1.arm.com) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1WkBCm-000229-TC for linux-arm-kernel@lists.infradead.org; Tue, 13 May 2014 11:49:09 +0000 Received: from hornet.Cambridge.Arm.com (hornet.cambridge.arm.com [10.2.201.45]) by collaborate-mta1.arm.com (Postfix) with ESMTP id 5BB3A13F8B8; Tue, 13 May 2014 06:48:40 -0500 (CDT) From: Pawel Moll To: Grant Likely , Rob Herring , Russell King Subject: [PATCH v3] of: Keep track of populated platform devices Date: Tue, 13 May 2014 12:48:36 +0100 Message-Id: <1399981716-24618-1-git-send-email-pawel.moll@arm.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: References: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20140513_044909_035656_C0478A92 X-CRM114-Status: GOOD ( 17.99 ) X-Spam-Score: -0.7 (/) Cc: devicetree@vger.kernel.org, Pawel Moll , linux-arm-kernel@lists.infradead.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , 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=-2.5 required=5.0 tests=BAYES_00,RP_MATCHES_RCVD, 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 In "Device Tree powered" systems, platform devices are usually massively populated with of_platform_populate() call, executed at some level of initcalls, either by generic architecture or by platform-specific code. There are situations though where certain devices must be created (and bound with drivers) before all the others. This presents a challenge, as devices created explicitly would be created again by of_platform_populate(). This patch tries to solve that issue in a generic way, adding a "populated" flag for a DT node description. Once set, this device will never be created again via of_* API, so of_platform_populate() will skip such nodes (and its children) in a similar way to the non-available ones. The flag is cleared when a device is being removed and returns the DT node by calling of_device_node_put() (it was missing from the amba device release function, added). Signed-off-by: Pawel Moll Reviewed-by: Rob Herring Acked-by: Grant Likely --- Changes since v2: - the populated flag is now cleared when the device is being removed by platform or amba bus code - added missing of_device_node_put() to amba_device_release() - renamed of_node_check_and_set_flag() to of_node_check_test_and_set_flag() to follow the bitops naming convention - didn't add Rob's ack as the patch changed too much Changes since v1: - added of_node_check_and_set_flag()... (atomic test and set) - ... used it to atomically mark a node... - ... clearing the bit on error path. drivers/amba/bus.c | 2 ++ drivers/of/platform.c | 18 +++++++++++++----- include/linux/of.h | 7 +++++++ include/linux/of_device.h | 2 ++ 4 files changed, 24 insertions(+), 5 deletions(-) diff --git a/drivers/amba/bus.c b/drivers/amba/bus.c index 3cf61a1..0f489fb 100644 --- a/drivers/amba/bus.c +++ b/drivers/amba/bus.c @@ -17,6 +17,7 @@ #include #include #include +#include #include @@ -268,6 +269,7 @@ static void amba_device_release(struct device *dev) { struct amba_device *d = to_amba_device(dev); + of_device_node_put(dev); if (d->res.parent) release_resource(&d->res); kfree(d); diff --git a/drivers/of/platform.c b/drivers/of/platform.c index bd47fbc..2d0c8b7 100644 --- a/drivers/of/platform.c +++ b/drivers/of/platform.c @@ -206,12 +206,13 @@ static struct platform_device *of_platform_device_create_pdata( { struct platform_device *dev; - if (!of_device_is_available(np)) + if (!of_device_is_available(np) || + of_node_test_and_set_flag(np, OF_POPULATED)) return NULL; dev = of_device_alloc(np, bus_id, parent); if (!dev) - return NULL; + goto err_clear_flag; #if defined(CONFIG_MICROBLAZE) dev->archdata.dma_mask = 0xffffffffUL; @@ -229,10 +230,14 @@ static struct platform_device *of_platform_device_create_pdata( if (of_device_add(dev) != 0) { platform_device_put(dev); - return NULL; + goto err_clear_flag; } return dev; + +err_clear_flag: + of_node_clear_flag(np, OF_POPULATED); + return NULL; } /** @@ -264,14 +269,15 @@ static struct amba_device *of_amba_device_create(struct device_node *node, pr_debug("Creating amba device %s\n", node->full_name); - if (!of_device_is_available(node)) + if (!of_device_is_available(node) || + of_node_test_and_set_flag(node, OF_POPULATED)) return NULL; dev = amba_device_alloc(NULL, 0, 0); if (!dev) { pr_err("%s(): amba_device_alloc() failed for %s\n", __func__, node->full_name); - return NULL; + goto err_clear_flag; } /* setup generic device info */ @@ -311,6 +317,8 @@ static struct amba_device *of_amba_device_create(struct device_node *node, err_free: amba_device_put(dev); +err_clear_flag: + of_node_clear_flag(node, OF_POPULATED); return NULL; } #else /* CONFIG_ARM_AMBA */ diff --git a/include/linux/of.h b/include/linux/of.h index 3bad8d1..3fd6079 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -130,6 +130,12 @@ static inline int of_node_check_flag(struct device_node *n, unsigned long flag) return test_bit(flag, &n->_flags); } +static inline int of_node_test_and_set_flag(struct device_node *n, + unsigned long flag) +{ + return test_and_set_bit(flag, &n->_flags); +} + static inline void of_node_set_flag(struct device_node *n, unsigned long flag) { set_bit(flag, &n->_flags); @@ -197,6 +203,7 @@ static inline unsigned long of_read_ulong(const __be32 *cell, int size) /* flag descriptions */ #define OF_DYNAMIC 1 /* node and properties were allocated via kmalloc */ #define OF_DETACHED 2 /* node has been detached from the device tree */ +#define OF_POPULATED 3 /* device already created for the node */ #define OF_IS_DYNAMIC(x) test_bit(OF_DYNAMIC, &x->_flags) #define OF_MARK_DYNAMIC(x) set_bit(OF_DYNAMIC, &x->_flags) diff --git a/include/linux/of_device.h b/include/linux/of_device.h index ef37021..fd14d46 100644 --- a/include/linux/of_device.h +++ b/include/linux/of_device.h @@ -41,6 +41,8 @@ extern int of_device_uevent_modalias(struct device *dev, struct kobj_uevent_env static inline void of_device_node_put(struct device *dev) { + if (dev->of_node) + of_node_clear_flag(dev->of_node, OF_POPULATED); of_node_put(dev->of_node); }