From patchwork Tue Nov 20 04:45:19 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Viresh Kumar X-Patchwork-Id: 12958 Return-Path: X-Original-To: patchwork@peony.canonical.com Delivered-To: patchwork@peony.canonical.com Received: from fiordland.canonical.com (fiordland.canonical.com [91.189.94.145]) by peony.canonical.com (Postfix) with ESMTP id 3B17A23E01 for ; Tue, 20 Nov 2012 04:45:30 +0000 (UTC) Received: from mail-ie0-f180.google.com (mail-ie0-f180.google.com [209.85.223.180]) by fiordland.canonical.com (Postfix) with ESMTP id 9E742A18C60 for ; Tue, 20 Nov 2012 04:45:29 +0000 (UTC) Received: by mail-ie0-f180.google.com with SMTP id e10so7647162iej.11 for ; Mon, 19 Nov 2012 20:45:29 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=x-forwarded-to:x-forwarded-for:delivered-to:received-spf:from:to:cc :subject:date:message-id:x-mailer:x-originalarrivaltime:x-mc-unique :content-type:content-transfer-encoding:x-gm-message-state; bh=qDFQjSDnNGL22+Jh0nMlDZ5dgb0SOKL/x7Sq1NmRGXo=; b=TukK+dXX2xFFjrzC5hVj9J9VPewnxmwMEXXVb3fy4oz1+RUFjbfnK61lx8835tzC/A V1GA6LkGpEBmk3xQKxzpfPNyAwIEi48/HtAeB9DVmonYXG/HJLBJi1wmY8N4fMGN+FuE hs27iPiLfFrbaoVUeI6HjZgDpXSkotWx1v5jWqF1a5j75dTX9+04rG5C2QgKwGVoX6eM YALUgSTvnWGAZp08IC3mTNdpuCpn+dhoPsIGM9Is70pyP3BU8ZwZGYKqIesU1YQ6wXJS IMACaFryVBhS6zALZg7T5RBlYdM7jaxnCir0c0xcZ2ekwFy+Lm+0J0hC2eswDFFGcTgi +Lxw== Received: by 10.50.213.34 with SMTP id np2mr8768580igc.57.1353386729021; Mon, 19 Nov 2012 20:45:29 -0800 (PST) X-Forwarded-To: linaro-patchwork@canonical.com X-Forwarded-For: patch@linaro.org linaro-patchwork@canonical.com Delivered-To: patches@linaro.org Received: by 10.50.67.148 with SMTP id n20csp268079igt; Mon, 19 Nov 2012 20:45:28 -0800 (PST) Received: by 10.216.72.5 with SMTP id s5mr5466565wed.154.1353386727411; Mon, 19 Nov 2012 20:45:27 -0800 (PST) Received: from service87.mimecast.com (service87.mimecast.com. [91.220.42.44]) by mx.google.com with ESMTP id n7si6331230wen.29.2012.11.19.20.45.26; Mon, 19 Nov 2012 20:45:27 -0800 (PST) Received-SPF: pass (google.com: domain of viresh.kumar2@arm.com designates 91.220.42.44 as permitted sender) client-ip=91.220.42.44; Authentication-Results: mx.google.com; spf=pass (google.com: domain of viresh.kumar2@arm.com designates 91.220.42.44 as permitted sender) smtp.mail=viresh.kumar2@arm.com Received: from cam-owa1.Emea.Arm.com (fw-tnat.cambridge.arm.com [217.140.96.21]) by service87.mimecast.com; Tue, 20 Nov 2012 04:45:26 +0000 Received: from localhost ([10.1.255.212]) by cam-owa1.Emea.Arm.com with Microsoft SMTPSVC(6.0.3790.0); Tue, 20 Nov 2012 04:45:23 +0000 From: Viresh Kumar To: rob.herring@calxeda.com, grant.likely@secretlab.ca Cc: spear-devel@list.st.com, devicetree-discuss@lists.ozlabs.org, linux-kernel@vger.kernel.org, andriy.shevchenko@intel.com, linaro-dev@lists.linaro.org, patches@linaro.org, swarren@wwwdotorg.org, Viresh Kumar Subject: [PATCH] dt: add helper function to read u8 & u16 variables & arrays Date: Tue, 20 Nov 2012 10:15:19 +0530 Message-Id: <0ee5b74534a09d75c14b22c2d9330c4971ab30fb.1353386646.git.viresh.kumar@linaro.org> X-Mailer: git-send-email 1.7.12.rc2.18.g61b472e X-OriginalArrivalTime: 20 Nov 2012 04:45:24.0140 (UTC) FILETIME=[DA9AE6C0:01CDC6D9] X-MC-Unique: 112112004452601801 X-Gm-Message-State: ALoCoQlyoYK5u/b+mUZisEBs/pG0bZGXtXwEXBp1UJTeGe/8WY5FOPoPL8BWoibyHgnT5zkEiUwK This adds following helper routines: - of_property_read_u8_array() - of_property_read_u16_array() - of_property_read_u8() - of_property_read_u16() This expects arrays from DT to be passed as: - u8 array: property = /bits/ 8 <0x50 0x60 0x70>; - u16 array: property = /bits/ 16 <0x5000 0x6000 0x7000>; Signed-off-by: Viresh Kumar Reviewed-by: Stephen Warren --- V2->V3: - Expect u8 & u16 arrays to be passed using: /bits/ 8 or 16 - remove common macro, as not much common now :( - Tested on ARM platform. drivers/of/base.c | 77 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ include/linux/of.h | 30 +++++++++++++++++++++ 2 files changed, 107 insertions(+) diff --git a/drivers/of/base.c b/drivers/of/base.c index af3b22a..f564e31 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -671,12 +671,89 @@ struct device_node *of_find_node_by_phandle(phandle handle) EXPORT_SYMBOL(of_find_node_by_phandle); /** + * 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. + * @propname: name of the property to be searched. + * @out_value: pointer to return value, modified only if return value is 0. + * @sz: number of array elements to read + * + * Search for a property in a device node and read 8-bit value(s) 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. + * + * dts entry of array should be like: + * property = /bits/ 8 <0x50 0x60 0x70>; + * + * The out_value is modified only if a valid u8 value can be decoded. + */ +int of_property_read_u8_array(const struct device_node *np, + const char *propname, u8 *out_values, size_t sz) +{ + struct property *prop = of_find_property(np, propname, NULL); + const u8 *val; + + if (!prop) + return -EINVAL; + if (!prop->value) + return -ENODATA; + if ((sz * sizeof(*out_values)) > prop->length) + return -EOVERFLOW; + + val = prop->value; + while (sz--) + *out_values++ = *val++; + return 0; +} +EXPORT_SYMBOL_GPL(of_property_read_u8_array); + +/** + * of_property_read_u16_array - Find and read an array of u16 from a property. + * + * @np: device node from which the property value is to be read. + * @propname: name of the property to be searched. + * @out_value: pointer to return value, modified only if return value is 0. + * @sz: number of array elements to read + * + * Search for a property in a device node and read 16-bit value(s) 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. + * + * dts entry of array should be like: + * property = /bits/ 16 <0x5000 0x6000 0x7000>; + * + * The out_value is modified only if a valid u16 value can be decoded. + */ +int of_property_read_u16_array(const struct device_node *np, + const char *propname, u16 *out_values, size_t sz) +{ + struct property *prop = of_find_property(np, propname, NULL); + const __be16 *val; + + if (!prop) + return -EINVAL; + if (!prop->value) + return -ENODATA; + if ((sz * sizeof(*out_values)) > prop->length) + return -EOVERFLOW; + + val = prop->value; + while (sz--) + *out_values++ = be16_to_cpup(val++); + return 0; +} +EXPORT_SYMBOL_GPL(of_property_read_u16_array); + +/** * of_property_read_u32_array - Find and read an array of 32 bit integers * from a property. * * @np: device node from which the property value is to be read. * @propname: name of the property to be searched. * @out_value: pointer to return value, modified only if return value is 0. + * @sz: number of array elements to read * * Search for a property in a device node and read 32-bit value(s) from * it. Returns 0 on success, -EINVAL if the property does not exist, diff --git a/include/linux/of.h b/include/linux/of.h index b4e50d5..bfdc130 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -223,6 +223,10 @@ 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_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, + const char *propname, u16 *out_values, size_t sz); extern int of_property_read_u32_array(const struct device_node *np, const char *propname, u32 *out_values, @@ -364,6 +368,18 @@ static inline struct device_node *of_find_compatible_node( return NULL; } +static inline int of_property_read_u8_array(const struct device_node *np, + const char *propname, u8 *out_values, size_t sz) +{ + return -ENOSYS; +} + +static inline int of_property_read_u16_array(const struct device_node *np, + const char *propname, u16 *out_values, size_t sz) +{ + return -ENOSYS; +} + static inline int of_property_read_u32_array(const struct device_node *np, const char *propname, u32 *out_values, size_t sz) @@ -470,6 +486,20 @@ static inline bool of_property_read_bool(const struct device_node *np, return prop ? true : false; } +static inline int of_property_read_u8(const struct device_node *np, + const char *propname, + u8 *out_value) +{ + return of_property_read_u8_array(np, propname, out_value, 1); +} + +static inline int of_property_read_u16(const struct device_node *np, + const char *propname, + u16 *out_value) +{ + return of_property_read_u16_array(np, propname, out_value, 1); +} + static inline int of_property_read_u32(const struct device_node *np, const char *propname, u32 *out_value)