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: 10709209 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 3FF9E17D5 for ; Mon, 3 Dec 2018 11:14:02 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 2DB9D283C8 for ; Mon, 3 Dec 2018 11:14:02 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 202FE28685; Mon, 3 Dec 2018 11:14:02 +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=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id CB8FB283C8 for ; Mon, 3 Dec 2018 11:14:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:References: In-Reply-To:Message-Id:Date:Subject:To:From:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=2leSgjB4NNPTHlWvPgWgaSJd2hZzFwJfZe0jX61bfQ4=; b=Dq5toOfGGBI0Fo0dtOUSt1nceB DjNkLKp967kZgSKctbe5Gk+3mGO4FyK8OHolqOEv8vhtHavO+ybMAYk9jAUvGB3EzRWz8i5umyCb6 Rvj2RBWReAtwIzdSt7sySzX5k3PrYHI2bx4B/jJcv/V3suhTmmD+98x39u+NT2vA/IFEbwtdch5BN nEOWkvRSb8dP3vMRV6VcoQkWk9gcW7GWf8J3DtPOejLOWyuvckKiH+6CYBZVFkIWqF6j0O0yUk3bl J7uS2jaIP02K3c6dO0+CHtY6WJzXOW57588E7U3aAxlYvURJLTKRET5eK96F4Y9j6V3HLMV6PtxHo ZFpf/aQQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gTmAo-0003bT-Ec; Mon, 03 Dec 2018 11:13:58 +0000 Received: from relmlor2.renesas.com ([210.160.252.172] helo=relmlie6.idc.renesas.com) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gTmAK-00033Z-Lu for linux-arm-kernel@lists.infradead.org; Mon, 03 Dec 2018 11:13:31 +0000 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 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> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20181203_031328_823926_E850EC6C X-CRM114-Status: UNSURE ( 8.64 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Phil Edworthy , linux-kernel@vger.kernel.org, Geert Uytterhoeven , =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= , Andy Shevchenko , linux-clk@vger.kernel.org, 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-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: 10709211 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 6F3B713BF for ; Mon, 3 Dec 2018 11:14:18 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 58E84287A1 for ; Mon, 3 Dec 2018 11:14:18 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 4B1FE2B326; Mon, 3 Dec 2018 11:14:18 +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=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=unavailable version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 5BC0F287A1 for ; Mon, 3 Dec 2018 11:14:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:References: In-Reply-To:Message-Id:Date:Subject:To:From:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=6MJDB0bFHONbqKbKqSp+DauLc4R219XYG9pTrbn6Umc=; b=dn/3yXmxKl5eb0Gmw+61WZ2YVN cCcFJbpcYEHlU0fofZ0Ob2v/dg+8sQB896AeWTzYXngyFSO8z700sEPjI9DJhgtAbh2nl8zCDLZmp XVUxPRVdQHYDtAEScoxu5ov6Lx8skTSAWSr/OnhtOELQMV2bouDJxGghPwig5HSkClYLKTDhsJ25P 2erx7n52sCs6XNQiQuhHTUO5idICc+cBQWY79vic8EUwuY9FpuRn73uDbBJw5re+z2ZalyxIUvjYf VZpTT9lhKZ/razEDbbk3i6XNBUGx0Zix1UQpaNRC+TT+YdBE4TvvckHJQDo1wOkQ7G/ba1wSCbHvG JujpevTw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gTmB1-0003tf-7M; Mon, 03 Dec 2018 11:14:11 +0000 Received: from relmlor1.renesas.com ([210.160.252.171] helo=relmlie5.idc.renesas.com) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gTmAf-0003C7-Pm for linux-arm-kernel@lists.infradead.org; Mon, 03 Dec 2018 11:14:06 +0000 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 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> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20181203_031350_117781_5F4AB335 X-CRM114-Status: GOOD ( 10.46 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Phil Edworthy , linux-kernel@vger.kernel.org, Geert Uytterhoeven , =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= , Andy Shevchenko , linux-clk@vger.kernel.org, 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-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);