From patchwork Thu Jul 17 14:13:19 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tomeu Vizoso X-Patchwork-Id: 4578281 Return-Path: X-Original-To: patchwork-alsa-devel@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 3DA4FC0514 for ; Thu, 17 Jul 2014 19:11:40 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 36B24201BF for ; Thu, 17 Jul 2014 19:11:39 +0000 (UTC) Received: from alsa0.perex.cz (alsa0.perex.cz [77.48.224.243]) by mail.kernel.org (Postfix) with ESMTP id C56F1201BA for ; Thu, 17 Jul 2014 19:11:37 +0000 (UTC) Received: by alsa0.perex.cz (Postfix, from userid 1000) id DAD9226565E; Thu, 17 Jul 2014 21:11:31 +0200 (CEST) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Spam-Level: X-Spam-Status: No, score=-1.8 required=5.0 tests=BAYES_00,DKIM_SIGNED, T_DKIM_INVALID,UNPARSEABLE_RELAY autolearn=no version=3.3.1 Received: from alsa0.perex.cz (localhost [IPv6:::1]) by alsa0.perex.cz (Postfix) with ESMTP id E808326557A; Thu, 17 Jul 2014 21:06:29 +0200 (CEST) X-Original-To: alsa-devel@alsa-project.org Delivered-To: alsa-devel@alsa-project.org Received: by alsa0.perex.cz (Postfix, from userid 1000) id 00ECC265577; Thu, 17 Jul 2014 16:14:48 +0200 (CEST) Received: from mail-we0-f180.google.com (mail-we0-f180.google.com [74.125.82.180]) by alsa0.perex.cz (Postfix) with ESMTP id 9FDBE265555 for ; Thu, 17 Jul 2014 16:14:38 +0200 (CEST) Received: by mail-we0-f180.google.com with SMTP id w61so3167745wes.25 for ; Thu, 17 Jul 2014 07:14:38 -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=4cAQuiu+ZNgCc9Z9o2A39hayqI2sL1J62jwIR78jcXA=; b=kgtetAKLdEeLt3pkPn6PXqTqTy2L7lJt6zFBbZQH1rctSszGiOMVo6RxODAEaXJ7J4 JrZvToPBT+l8PjTrQeKaD0loMO8qK0V1o3Y0oLLKQf5Vy9HBdgM4DiTn54daPlQG33Y+ 8WX0+aV9axsHX07q07vdL0e1oeAltbVGIEZHjgM8E2gyp4tCq//9odzbQIePjZ0YTnTe m2ZIdkOMY58zy8WY4Eq0BqY8YHE6Oj9tyVQfH7r+mgAbDt6h1ogzcI6Ol/O1hw3kiosG XJ3c1zvxEL8ybjSm3A111u37ddzZgMapPkJaEbSzMo2oZz6xWkzwMcPzFRkeCWsl/U/l /x4g== X-Received: by 10.180.8.10 with SMTP id n10mr22886643wia.41.1405606478293; Thu, 17 Jul 2014 07:14:38 -0700 (PDT) Received: from cizrna.lan (37-48-42-212.tmcz.cz. [37.48.42.212]) by mx.google.com with ESMTPSA id rw4sm6412963wjb.44.2014.07.17.07.14.28 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 17 Jul 2014 07:14:37 -0700 (PDT) From: Tomeu Vizoso To: Mike Turquette Date: Thu, 17 Jul 2014 16:13:19 +0200 Message-Id: <1405606399-26608-7-git-send-email-tomeu.vizoso@collabora.com> X-Mailer: git-send-email 1.9.3 In-Reply-To: <1405606399-26608-1-git-send-email-tomeu.vizoso@collabora.com> References: <1405606399-26608-1-git-send-email-tomeu.vizoso@collabora.com> X-Mailman-Approved-At: Thu, 17 Jul 2014 21:06:20 +0200 Cc: Andrew Lunn , Ulf Hansson , Prashant Gaikwad , Tony Lindgren , Benjamin Herrenschmidt , Tomasz Figa , alsa-devel@alsa-project.org, Thierry Reding , Paul Mackerras , Sylwester Nawrocki , Daniel Walker , linux-arch@vger.kernel.org, Boris Brezillon , linux-samsung-soc@vger.kernel.org, Kukjin Kim , Russell King , =?UTF-8?q?Emilio=20L=C3=B3pez?= , Takashi Iwai , Michal Simek , Kyungmin Park , Kevin Hilman , linux-arm-kernel@lists.infradead.org, patches@opensource.wolfsonmicro.com, Viresh Kumar , David Brown , Anatolij Gustschin , Dinh Nguyen , Sebastian Hesselbarth , Jason Cooper , Arnd Bergmann , Stephen Warren , linux-arm-msm@vger.kernel.org, spear-devel@list.st.com, Barry Song , Mark Brown , linux-rpi-kernel@lists.infradead.org, Ben Dooks , linux-tegra@vger.kernel.org, linux-omap@vger.kernel.org, Sascha Hauer , Shawn Guo , Paul Walmsley , Tomeu Vizoso , Peter De Schrijver , Liam Girdwood , linux-kernel@vger.kernel.org, rabin@rab.in, Bryan Huntsman , Santosh Shilimkar , =?UTF-8?q?Beno=C3=AEt=20Cousson?= , Maxime Ripard , linux-media@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Javier Martinez Canillas , Mauro Carvalho Chehab Subject: [alsa-devel] [PATCH v4 6/6] clk: Add floor and ceiling constraints to clock rates X-BeenThere: alsa-devel@alsa-project.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: "Alsa-devel mailing list for ALSA developers - http://www.alsa-project.org" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.org X-Virus-Scanned: ClamAV using ClamSMTP Adds a way for clock consumers to set maximum and minimum rates. This can be used for thermal drivers to set ceiling rates, or by misc. drivers to set floor rates to assure a minimum performance level. Signed-off-by: Tomeu Vizoso --- drivers/clk/clk.c | 103 ++++++++++++++++++++++++++++++++++++++++++++ drivers/clk/clk.h | 1 + drivers/clk/clkdev.c | 2 +- include/linux/clk-private.h | 1 + include/linux/clk.h | 18 ++++++++ 5 files changed, 124 insertions(+), 1 deletion(-) diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index f1cdc01..90db677 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -23,6 +23,19 @@ #include "clk.h" +enum constraint_type { + CONSTRAINT_FLOOR, + CONSTRAINT_CEILING, +}; + +struct rate_constraint { + struct hlist_node node; + const char *dev_id; + const char *con_id; + enum constraint_type type; + unsigned long rate; +}; + static DEFINE_SPINLOCK(enable_lock); static DEFINE_MUTEX(prepare_lock); @@ -1653,6 +1666,7 @@ static void clk_change_rate(struct clk_core *clk) int clk_provider_set_rate(struct clk_core *clk, unsigned long rate) { struct clk_core *top, *fail_clk; + struct rate_constraint *constraint; int ret = 0; if (!clk) @@ -1661,6 +1675,17 @@ int clk_provider_set_rate(struct clk_core *clk, unsigned long rate) /* prevent racing with updates to the clock topology */ clk_prepare_lock(); + hlist_for_each_entry(constraint, &clk->rate_constraints, node) { + switch (constraint->type) { + case CONSTRAINT_FLOOR: + rate = max(rate, constraint->rate); + break; + case CONSTRAINT_CEILING: + rate = min(rate, constraint->rate); + break; + } + } + /* bail early if nothing to do */ if (rate == clk_provider_get_rate(clk)) goto out; @@ -1727,6 +1752,65 @@ int clk_set_rate(struct clk *clk_user, unsigned long rate) } EXPORT_SYMBOL_GPL(clk_set_rate); +static struct rate_constraint *__ensure_constraint(struct clk *clk_user, + enum constraint_type type) +{ + struct clk_core *clk = clk_to_clk_core(clk_user); + struct rate_constraint *constraint = NULL; + bool found = false; + + hlist_for_each_entry(constraint, &clk->rate_constraints, node) { + if (constraint->dev_id == clk_user->dev_id && + constraint->con_id == clk_user->con_id && + constraint->type == type) + found = true; + } + + if (!found) { + constraint = kzalloc(sizeof(*constraint), GFP_KERNEL); + if (!constraint) + return NULL; + hlist_add_head(&constraint->node, &clk->rate_constraints); + } + + return constraint; +} + +static int __clk_set_constraint(struct clk *clk_user, unsigned long rate, + enum constraint_type type) +{ + struct clk_core *clk = clk_to_clk_core(clk_user); + struct rate_constraint *constraint; + int ret; + + clk_prepare_lock(); + + constraint = __ensure_constraint(clk_user, type); + if (!constraint) + return -ENOMEM; + + constraint->rate = rate; + + /* Update the rate so the new constraint is taken into account */ + ret = clk_provider_set_rate(clk, clk_provider_get_rate(clk)); + + clk_prepare_unlock(); + + return ret; +} + +int clk_set_floor_rate(struct clk *clk_user, unsigned long rate) +{ + return __clk_set_constraint(clk_user, rate, CONSTRAINT_FLOOR); +} +EXPORT_SYMBOL_GPL(clk_set_floor_rate); + +int clk_set_ceiling_rate(struct clk *clk_user, unsigned long rate) +{ + return __clk_set_constraint(clk_user, rate, CONSTRAINT_CEILING); +} +EXPORT_SYMBOL_GPL(clk_set_ceiling_rate); + struct clk_core *clk_provider_get_parent(struct clk_core *clk) { struct clk_core *parent; @@ -2072,6 +2156,8 @@ int __clk_init(struct device *dev, struct clk_core *clk) } } + INIT_HLIST_HEAD(&clk->rate_constraints); + /* * optional platform-specific magic * @@ -2508,6 +2594,23 @@ int clk_notifier_unregister(struct clk *clk_user, struct notifier_block *nb) } EXPORT_SYMBOL_GPL(clk_notifier_unregister); +void __clk_free_clk(struct clk *clk_user) +{ + struct clk_core *clk = clk_to_clk_core(clk_user); + struct rate_constraint *constraint; + struct hlist_node *tmp; + + hlist_for_each_entry_safe(constraint, tmp, &clk->rate_constraints, node) { + if (constraint->dev_id == clk_user->dev_id && + constraint->con_id == clk_user->con_id) { + hlist_del(&constraint->node); + kfree(constraint); + } + } + + kfree(clk_user); +} + #ifdef CONFIG_OF /** * struct of_clk_provider - Clock provider registration structure diff --git a/drivers/clk/clk.h b/drivers/clk/clk.h index 49eff38..005deb3 100644 --- a/drivers/clk/clk.h +++ b/drivers/clk/clk.h @@ -21,4 +21,5 @@ void of_clk_unlock(void); #if defined(CONFIG_COMMON_CLK) struct clk *__clk_create_clk(struct clk_core *clk_core, const char *dev, const char *con); +void __clk_free_clk(struct clk *clk_user); #endif diff --git a/drivers/clk/clkdev.c b/drivers/clk/clkdev.c index 517a25b..8a6a398 100644 --- a/drivers/clk/clkdev.c +++ b/drivers/clk/clkdev.c @@ -269,7 +269,7 @@ void clk_put(struct clk *clk) #if defined(CONFIG_COMMON_CLK) clk_core_t *core = clk_to_clk_core(clk); - kfree(clk); + __clk_free_clk(clk); __clk_put(core); #else __clk_put(clk); diff --git a/include/linux/clk-private.h b/include/linux/clk-private.h index 9657fc8..a8279e1 100644 --- a/include/linux/clk-private.h +++ b/include/linux/clk-private.h @@ -48,6 +48,7 @@ struct clk_core { unsigned long accuracy; struct hlist_head children; struct hlist_node child_node; + struct hlist_head rate_constraints; unsigned int notifier_count; #ifdef CONFIG_DEBUG_FS struct dentry *dentry; diff --git a/include/linux/clk.h b/include/linux/clk.h index f46a2eb..066b100 100644 --- a/include/linux/clk.h +++ b/include/linux/clk.h @@ -275,6 +275,24 @@ long clk_round_rate(struct clk *clk, unsigned long rate); int clk_set_rate(struct clk *clk, unsigned long rate); /** + * clk_set_floor_rate - set a minimum clock rate for a clock source + * @clk: clock source + * @rate: desired minimum clock rate in Hz + * + * Returns success (0) or negative errno. + */ +int clk_set_floor_rate(struct clk *clk, unsigned long rate); + +/** + * clk_set_ceiling_rate - set a maximum clock rate for a clock source + * @clk: clock source + * @rate: desired maximum clock rate in Hz + * + * Returns success (0) or negative errno. + */ +int clk_set_ceiling_rate(struct clk *clk, unsigned long rate); + +/** * clk_set_parent - set the parent clock source for this clock * @clk: clock source * @parent: parent clock source