From patchwork Mon Dec 3 11:13:08 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Phil Edworthy X-Patchwork-Id: 10709201 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 4481B17D5 for ; Mon, 3 Dec 2018 11:13:29 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 363F12B319 for ; Mon, 3 Dec 2018 11:13:29 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 2AB392B32B; Mon, 3 Dec 2018 11:13:29 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id CC63E2B322 for ; Mon, 3 Dec 2018 11:13:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725883AbeLCLOD (ORCPT ); Mon, 3 Dec 2018 06:14:03 -0500 Received: from relmlor2.renesas.com ([210.160.252.172]:47716 "EHLO relmlie6.idc.renesas.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725907AbeLCLOD (ORCPT ); Mon, 3 Dec 2018 06:14:03 -0500 Received: from unknown (HELO relmlir5.idc.renesas.com) ([10.200.68.151]) by relmlie6.idc.renesas.com with ESMTP; 03 Dec 2018 20:13:26 +0900 Received: from vbox.ree.adwin.renesas.com (unknown [10.226.37.67]) by relmlir5.idc.renesas.com (Postfix) with ESMTP id 73562402D031; Mon, 3 Dec 2018 20:13:24 +0900 (JST) From: Phil Edworthy To: Michael Turquette , Stephen Boyd , Russell King Cc: Andy Shevchenko , Geert Uytterhoeven , =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= , linux-clk@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Phil Edworthy Subject: [PATCH v9 1/2] clk: Add comment about __of_clk_get_by_name() error values Date: Mon, 3 Dec 2018 11:13:08 +0000 Message-Id: <20181203111309.3709-2-phil.edworthy@renesas.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20181203111309.3709-1-phil.edworthy@renesas.com> References: <20181203111309.3709-1-phil.edworthy@renesas.com> Sender: linux-clk-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-clk@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP It's not immediately obvious from the code that failure to get a clock provider can return either -ENOENT or -EINVAL. Therefore, add a comment to highlight this. Signed-off-by: Phil Edworthy Reviewed-by: Andy Shevchenko --- drivers/clk/clkdev.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/clk/clkdev.c b/drivers/clk/clkdev.c index 9ab3db8b3988..cc5df3970cd3 100644 --- a/drivers/clk/clkdev.c +++ b/drivers/clk/clkdev.c @@ -52,6 +52,12 @@ struct clk *of_clk_get(struct device_node *np, int index) } EXPORT_SYMBOL(of_clk_get); +/* + * Beware the return values when np is valid, but no clock provider is found. + * If name = NULL, the function returns -ENOENT. + * If name != NULL, the function returns -EINVAL. This is because __of_clk_get() + * is called even if of_property_match_string() returns an error. + */ static struct clk *__of_clk_get_by_name(struct device_node *np, const char *dev_id, const char *name) From patchwork Mon Dec 3 11:13:09 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Phil Edworthy X-Patchwork-Id: 10709205 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id DBB1D13BF for ; Mon, 3 Dec 2018 11:13:41 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id CBCDE283C8 for ; Mon, 3 Dec 2018 11:13:41 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id C008328627; Mon, 3 Dec 2018 11:13:41 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 4E99228685 for ; Mon, 3 Dec 2018 11:13:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726180AbeLCLOQ (ORCPT ); Mon, 3 Dec 2018 06:14:16 -0500 Received: from relmlor1.renesas.com ([210.160.252.171]:59999 "EHLO relmlie5.idc.renesas.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725907AbeLCLOQ (ORCPT ); Mon, 3 Dec 2018 06:14:16 -0500 Received: from unknown (HELO relmlir5.idc.renesas.com) ([10.200.68.151]) by relmlie5.idc.renesas.com with ESMTP; 03 Dec 2018 20:13:38 +0900 Received: from vbox.ree.adwin.renesas.com (unknown [10.226.37.67]) by relmlir5.idc.renesas.com (Postfix) with ESMTP id BB782402D031; Mon, 3 Dec 2018 20:13:35 +0900 (JST) From: Phil Edworthy To: Michael Turquette , Stephen Boyd , Russell King Cc: Andy Shevchenko , Geert Uytterhoeven , =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= , linux-clk@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Phil Edworthy Subject: [PATCH v9 2/2] clk: Add (devm_)clk_get_optional() functions Date: Mon, 3 Dec 2018 11:13:09 +0000 Message-Id: <20181203111309.3709-3-phil.edworthy@renesas.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20181203111309.3709-1-phil.edworthy@renesas.com> References: <20181203111309.3709-1-phil.edworthy@renesas.com> Sender: linux-clk-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-clk@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This adds clk_get_optional() and devm_clk_get_optional() functions to get optional clocks. They behave the same as (devm_)clk_get() except where there is no clock producer. In this case, instead of returning -ENOENT, the function returns NULL. This makes error checking simpler and allows clk_prepare_enable, etc to be called on the returned reference without additional checks. Signed-off-by: Phil Edworthy Reviewed-by: Andy Shevchenko --- v9: - Add brackets after devm_clk_get so people know it's a function. - Add kernel doc for clk_get_optional(). v8: - Remove else clause v7: - Instead of messing with the core functions, simply wrap them for the _optional() versions. By putting clk_get_optional() inline in the header file, we can get rid of the arch specific patches as well. v6: - Add doxygen style comment for devm_clk_get_optional() args v5: - No changes. v4: - No changes. v3: - No changes. --- drivers/clk/clk-devres.c | 11 +++++++++++ include/linux/clk.h | 36 ++++++++++++++++++++++++++++++++++++ 2 files changed, 47 insertions(+) diff --git a/drivers/clk/clk-devres.c b/drivers/clk/clk-devres.c index 12c87457eca1..8e8893168676 100644 --- a/drivers/clk/clk-devres.c +++ b/drivers/clk/clk-devres.c @@ -34,6 +34,17 @@ struct clk *devm_clk_get(struct device *dev, const char *id) } EXPORT_SYMBOL(devm_clk_get); +struct clk *devm_clk_get_optional(struct device *dev, const char *id) +{ + struct clk *clk = devm_clk_get(dev, id); + + if (clk == ERR_PTR(-ENOENT)) + return NULL; + + return clk; +} +EXPORT_SYMBOL(devm_clk_get_optional); + struct clk_bulk_devres { struct clk_bulk_data *clks; int num_clks; diff --git a/include/linux/clk.h b/include/linux/clk.h index a7773b5c0b9f..d8bc1a856b39 100644 --- a/include/linux/clk.h +++ b/include/linux/clk.h @@ -383,6 +383,17 @@ int __must_check devm_clk_bulk_get_all(struct device *dev, */ struct clk *devm_clk_get(struct device *dev, const char *id); +/** + * devm_clk_get_optional - lookup and obtain a managed reference to an optional + * clock producer. + * @dev: device for clock "consumer" + * @id: clock consumer ID + * + * Behaves the same as devm_clk_get() except where there is no clock producer. + * In this case, instead of returning -ENOENT, the function returns NULL. + */ +struct clk *devm_clk_get_optional(struct device *dev, const char *id); + /** * devm_get_clk_from_child - lookup and obtain a managed reference to a * clock producer from child node. @@ -718,6 +729,12 @@ static inline struct clk *devm_clk_get(struct device *dev, const char *id) return NULL; } +static inline struct clk *devm_clk_get_optional(struct device *dev, + const char *id) +{ + return NULL; +} + static inline int __must_check devm_clk_bulk_get(struct device *dev, int num_clks, struct clk_bulk_data *clks) { @@ -862,6 +879,25 @@ static inline void clk_bulk_disable_unprepare(int num_clks, clk_bulk_unprepare(num_clks, clks); } +/** + * clk_get_optional - lookup and obtain a reference to an optional clock + * producer. + * @dev: device for clock "consumer" + * @id: clock consumer ID + * + * Behaves the same as clk_get() except where there is no clock producer. In + * this case, instead of returning -ENOENT, the function returns NULL. + */ +static inline struct clk *clk_get_optional(struct device *dev, const char *id) +{ + struct clk *clk = clk_get(dev, id); + + if (clk == ERR_PTR(-ENOENT)) + return NULL; + + return clk; +} + #if defined(CONFIG_OF) && defined(CONFIG_COMMON_CLK) struct clk *of_clk_get(struct device_node *np, int index); struct clk *of_clk_get_by_name(struct device_node *np, const char *name);