From patchwork Tue Apr 2 04:39:05 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tony Prisk X-Patchwork-Id: 2374381 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) by patchwork1.kernel.org (Postfix) with ESMTP id 052513FDDA for ; Tue, 2 Apr 2013 04:42:19 +0000 (UTC) Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1UMt0a-0001b2-Lx; Tue, 02 Apr 2013 04:39:44 +0000 Received: from server.prisktech.co.nz ([115.188.14.127]) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1UMt03-0001T5-6I for linux-arm-kernel@lists.infradead.org; Tue, 02 Apr 2013 04:39:13 +0000 Received: from localhost.localdomain (unknown [192.168.0.102]) by server.prisktech.co.nz (Postfix) with ESMTP id 3E627FC09A0; Tue, 2 Apr 2013 17:39:09 +1300 (NZDT) From: Tony Prisk To: linux.walleij@linaro.org Subject: [PATCHv4 1/6] of: Add support for reading a u32 from a multi-value property. Date: Tue, 2 Apr 2013 17:39:05 +1300 Message-Id: <1364877550-25921-2-git-send-email-linux@prisktech.co.nz> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1364877550-25921-1-git-send-email-linux@prisktech.co.nz> References: <1364877550-25921-1-git-send-email-linux@prisktech.co.nz> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20130402_003913_016338_624C1DB3 X-CRM114-Status: GOOD ( 15.22 ) X-Spam-Score: -4.2 (----) X-Spam-Report: SpamAssassin version 3.3.2 on merlin.infradead.org summary: Content analysis details: (-4.2 points) pts rule name description ---- ---------------------- -------------------------------------------------- -2.3 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] Cc: vt8500-wm8505-linux-kernel@googlegroups.com, Tony Prisk , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, swarren@wwwdotorg.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 This patch adds an of_property_read_u32_index() function to allow reading a single indexed u32 value from a property containing multiple u32 values. Signed-off-by: Tony Prisk Reviewed-by: Stephen Warren --- drivers/of/base.c | 33 +++++++++++++++++++++++++++++++++ include/linux/of.h | 9 +++++++++ 2 files changed, 42 insertions(+) diff --git a/drivers/of/base.c b/drivers/of/base.c index 321d3ef..f6c89ed 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -746,6 +746,39 @@ struct device_node *of_find_node_by_phandle(phandle handle) EXPORT_SYMBOL(of_find_node_by_phandle); /** + * of_property_read_u32_index - Find and read a u32 from a multi-value property. + * + * @np: device node from which the property value is to be read. + * @propname: name of the property to be searched. + * @index: index of the u32 in the list of values + * @out_value: pointer to return value, modified only if no error. + * + * Search for a property in a device node and read nth 32-bit value from + * it. Returns 0 on success, -EINVAL if the property does not exist, + * -ENODATA if property does not have a value, and -EOVERFLOW if the + * property data isn't large enough. + * + * The out_value is modified only if a valid u32 value can be decoded. + */ +int of_property_read_u32_index(const struct device_node *np, + const char *propname, + u32 index, u32 *out_value) +{ + struct property *prop = of_find_property(np, propname, NULL); + + if (!prop) + return -EINVAL; + if (!prop->value) + return -ENODATA; + if (((index + 1) * sizeof(*out_value)) > prop->length) + return -EOVERFLOW; + + *out_value = be32_to_cpup(((__be32 *)prop->value) + index); + return 0; +} +EXPORT_SYMBOL_GPL(of_property_read_u32_index); + +/** * of_property_read_u8_array - Find and read an array of u8 from a property. * * @np: device node from which the property value is to be read. diff --git a/include/linux/of.h b/include/linux/of.h index a0f1292..c0747a4 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -235,6 +235,9 @@ extern struct device_node *of_find_node_with_property( extern struct property *of_find_property(const struct device_node *np, const char *name, int *lenp); +extern int of_property_read_u32_index(const struct device_node *np, + const char *propname, + u32 index, u32 *out_value); extern int of_property_read_u8_array(const struct device_node *np, const char *propname, u8 *out_values, size_t sz); extern int of_property_read_u16_array(const struct device_node *np, @@ -394,6 +397,12 @@ static inline struct device_node *of_find_compatible_node( return NULL; } +static inline int of_property_read_u32_index(const struct device_node *np, + const char *propname, u32 index, u32 *out_value) +{ + return -ENOSYS; +} + static inline int of_property_read_u8_array(const struct device_node *np, const char *propname, u8 *out_values, size_t sz) {