From patchwork Thu Apr 17 11:28:49 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrzej Hajda X-Patchwork-Id: 4007921 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 [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 67BF39F391 for ; Thu, 17 Apr 2014 11:32:44 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 71CC120380 for ; Thu, 17 Apr 2014 11:32:43 +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 8DCC22037B for ; Thu, 17 Apr 2014 11:32:42 +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 1WakWJ-0007za-PG; Thu, 17 Apr 2014 11:30:19 +0000 Received: from mailout1.w1.samsung.com ([210.118.77.11]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1WakW7-0006fn-Mr for linux-arm-kernel@lists.infradead.org; Thu, 17 Apr 2014 11:30:08 +0000 Received: from eucpsbgm1.samsung.com (unknown [203.254.199.244]) by mailout1.w1.samsung.com (Oracle Communications Messaging Server 7u4-24.01(7.0.4.24.0) 64bit (built Nov 17 2011)) with ESMTP id <0N46008ZUALH3270@mailout1.w1.samsung.com> for linux-arm-kernel@lists.infradead.org; Thu, 17 Apr 2014 12:29:41 +0100 (BST) X-AuditID: cbfec7f4-b7f796d000005a13-ae-534fbb26c268 Received: from eusync3.samsung.com ( [203.254.199.213]) by eucpsbgm1.samsung.com (EUCPMTA) with SMTP id 57.5C.23059.62BBF435; Thu, 17 Apr 2014 12:29:42 +0100 (BST) Received: from AMDC1061.digital.local ([106.116.147.88]) by eusync3.samsung.com (Oracle Communications Messaging Server 7u4-23.01 (7.0.4.23.0) 64bit (built Aug 10 2011)) with ESMTPA id <0N4600HX9AK8AS20@eusync3.samsung.com>; Thu, 17 Apr 2014 12:29:42 +0100 (BST) From: Andrzej Hajda To: dri-devel@lists.freedesktop.org Subject: [PATCH RFC 2/3] drivers/base: provide lightweight framework for componentized devices Date: Thu, 17 Apr 2014 13:28:49 +0200 Message-id: <1397734130-21019-3-git-send-email-a.hajda@samsung.com> X-Mailer: git-send-email 1.8.3.2 In-reply-to: <1397734130-21019-1-git-send-email-a.hajda@samsung.com> References: <1397734130-21019-1-git-send-email-a.hajda@samsung.com> X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFprPLMWRmVeSWpSXmKPExsVy+t/xq7pqu/2DDTbsk7S4te4cq0XvuZNM Fn8nHWO3uPL1PZtF8+L1bBaT7k9gsTjb9IbdYtPja6wWl3fNYbOYcX4fk8Xty7wWa4/cZbdY P+M1iwOvR0tzD5vH71+TGD22f3vA6rF/7hp2j/vdx5k8Ni+p9+jbsorR4/MmuQCOKC6blNSc zLLUIn27BK6MZ59DC7q1KpY+PMHcwPhRqYuRk0NCwERi2ufNrBC2mMSFe+vZuhi5OIQEljJK zDy8mhnC6WOSeDVtOyNIFZuApsTfzTfZQGwRAWWJvxNXMYIUMQtsZ5FoOjoRLCEskCAx7d82 li5GDg4WAVWJvk1VIGFeAWeJW42dUNsUJJZ9WcsMYnMKuEi8+9fFClIuBFTz/a/tBEbeBYwM qxhFU0uTC4qT0nMN9YoTc4tL89L1kvNzNzFCAvXLDsbFx6wOMQpwMCrx8HL89gsWYk0sK67M PcQowcGsJMLbvN4/WIg3JbGyKrUoP76oNCe1+BAjEwenVAPjzBMSet+6xL6cm5sp2/trUtzE gxNcU306HphX9s76d9i4P2HqTE9+v9mGu070cUs1T5gUe2un7WFNkxkv/9hfecvBZ6syb/Xe //E7laY6sxx7plrWJ5L7dpKxsZjiZO5ZNff6OOSd7SUWOTMecM6TeGrYqSd3TmvvnVU7zD1O 7GyYOdXEVsRdiaU4I9FQi7moOBEA+UYTXTICAAA= X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20140417_043007_912414_53C23E5F X-CRM114-Status: GOOD ( 17.75 ) X-Spam-Score: -5.7 (-----) Cc: "moderated list:ARM/S5P EXYNOS AR..." , Russell King - ARM Linux , Arnd Bergmann , David Airlie , Greg Kroah-Hartman , Tomasz Figa , open list , Inki Dae , Andrzej Hajda , Kyungmin Park , "moderated list:ARM/S5P EXYNOS AR..." , Marek Szyprowski 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=-2.6 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 Many subsystems (eg. DRM, ALSA) requires that multiple devices should be composed into one superdevice. The superdevice cannot start until all components are ready and it should stop before any of its components becomes not-ready. This framework provides a way to track readiness of all components with minimal impact on the code of the drivers. The superdevice provides pending_components structure and adds all components to it, device drivers removes themselves from the list if they becomes ready. If the list becomes empty callback is fired which causes superdevice to start. Later if any components wants to become not-ready it adds again itself to the list and callback is fired to stop superdevice. Signed-off-by: Andrzej Hajda --- drivers/base/Kconfig | 3 ++ drivers/base/Makefile | 1 + drivers/base/pending_components.c | 93 ++++++++++++++++++++++++++++++++++++++ include/linux/pending_components.h | 30 ++++++++++++ 4 files changed, 127 insertions(+) create mode 100644 drivers/base/pending_components.c create mode 100644 include/linux/pending_components.h diff --git a/drivers/base/Kconfig b/drivers/base/Kconfig index ec36e77..71ce050 100644 --- a/drivers/base/Kconfig +++ b/drivers/base/Kconfig @@ -278,4 +278,7 @@ config CMA_AREAS endif +config PENDING_COMPONENTS + boolean + endmenu diff --git a/drivers/base/Makefile b/drivers/base/Makefile index 04b314e..3a51654 100644 --- a/drivers/base/Makefile +++ b/drivers/base/Makefile @@ -22,6 +22,7 @@ obj-$(CONFIG_SYS_HYPERVISOR) += hypervisor.o obj-$(CONFIG_REGMAP) += regmap/ obj-$(CONFIG_SOC_BUS) += soc.o obj-$(CONFIG_PINCTRL) += pinctrl.o +obj-$(CONFIG_PENDING_COMPONENTS) += pending_components.o ccflags-$(CONFIG_DEBUG_DRIVER) := -DDEBUG diff --git a/drivers/base/pending_components.c b/drivers/base/pending_components.c new file mode 100644 index 0000000..f15104e --- /dev/null +++ b/drivers/base/pending_components.c @@ -0,0 +1,93 @@ +/* + * Lightweight framework for handling componentized devices. + * + * Copyright (c) 2014 Samsung Electronics Co., Ltd + * Andrzej Hajda + * + * 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. + * + * pending_components structure contains list of components which are not yet + * ready. Components can remove or add themselves from/to the list. If the list + * becomes empty/non-empty optional callback is fired. +*/ + +#include +#include + +struct pending_components_node { + struct list_head list; + void *data; +}; + +int pending_components_insert(struct pending_components *set, void *item) +{ + struct pending_components_node *n; + int ret = 0; + + mutex_lock(&set->lock); + + list_for_each_entry(n, &set->list, list) { + if (n->data == item) + goto out; + } + + n = kmalloc(sizeof(*n), GFP_KERNEL); + if (!n) { + ret = -ENOMEM; + goto out; + } + + n->data = item; + list_add_tail(&n->list, &set->list); + if (set->callback && set->list.next == set->list.prev) + ret = set->callback(set, false); + +out: + mutex_unlock(&set->lock); + + return ret; +} + +int pending_components_delete(struct pending_components *set, void *item) +{ + struct pending_components_node *n; + int ret = 0; + + mutex_lock(&set->lock); + + list_for_each_entry(n, &set->list, list) { + if (n->data == item) { + list_del(&n->list); + kfree(n); + if (set->callback && list_empty(&set->list)) + ret = set->callback(set, true); + break; + } + } + + mutex_unlock(&set->lock); + + return ret; +} + +void pending_components_set_callback(struct pending_components *set, + pending_components_callback cb) +{ + mutex_lock(&set->lock); + + set->callback = cb; + + mutex_unlock(&set->lock); +} + +void pending_components_cleanup(struct pending_components *set) +{ + struct pending_components_node *n, *tmp; + + list_for_each_entry_safe(n, tmp, &set->list, list) { + list_del(&n->list); + kfree(n); + } +} diff --git a/include/linux/pending_components.h b/include/linux/pending_components.h new file mode 100644 index 0000000..dd29616 --- /dev/null +++ b/include/linux/pending_components.h @@ -0,0 +1,30 @@ +#ifndef PENDING_COMPONENTS_H +#define PENDING_COMPONENTS_H + +#include +#include + +struct pending_components; + +typedef int (*pending_components_callback)(struct pending_components *set, + bool empty); + +struct pending_components { + struct mutex lock; + struct list_head list; + pending_components_callback callback; +}; + +#define DEFINE_PENDING_COMPONENTS(set) \ + struct pending_components set = { \ + .lock = __MUTEX_INITIALIZER(set.lock), \ + .list = LIST_HEAD_INIT(set.list) \ + } + +int pending_components_insert(struct pending_components *set, void *item); +int pending_components_delete(struct pending_components *set, void *item); +void pending_components_set_callback(struct pending_components *set, + pending_components_callback cb); +void pending_components_cleanup(struct pending_components *set); + +#endif /* PENDING_COMPONENTS_H */