Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752222Ab2KFOSr (ORCPT ); Tue, 6 Nov 2012 09:18:47 -0500 Received: from mail-oa0-f46.google.com ([209.85.219.46]:58710 "EHLO mail-oa0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750989Ab2KFOSp (ORCPT ); Tue, 6 Nov 2012 09:18:45 -0500 Message-ID: <50991C41.50705@gmail.com> Date: Tue, 06 Nov 2012 08:18:41 -0600 From: Rob Herring User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:16.0) Gecko/20121028 Thunderbird/16.0.2 MIME-Version: 1.0 To: Viresh Kumar CC: rob.herring@calxeda.com, grant.likely@secretlab.ca, linaro-dev@lists.linaro.org, andriy.shevchenko@intel.com, patches@linaro.org, devicetree-discuss@lists.ozlabs.org, spear-devel@list.st.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH Resend V2] dt: add helper function to read u8 & u16 variables & arrays References: <64c5278ebdec503f83e9b7002bf13affb7f3260f.1351225085.git.viresh.kumar@linaro.org> In-Reply-To: <64c5278ebdec503f83e9b7002bf13affb7f3260f.1351225085.git.viresh.kumar@linaro.org> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6693 Lines: 195 On 10/25/2012 11:20 PM, Viresh Kumar wrote: > This adds following helper routines: > - of_property_read_u8_array() > - of_property_read_u16_array() > - of_property_read_u8() > - of_property_read_u16() > > First two actually share most of the code with of_property_read_u32_array(), so > the common part is taken out into a macro, which can be used by all three > *_array() routines. > > Signed-off-by: Viresh Kumar > --- > V1->V2: > ----- > - Use typeof() in of_property_read_array() macro instead of passing type to it > > drivers/of/base.c | 73 +++++++++++++++++++++++++++++++++++++++++++----------- > include/linux/of.h | 30 ++++++++++++++++++++++ > 2 files changed, 89 insertions(+), 14 deletions(-) > > diff --git a/drivers/of/base.c b/drivers/of/base.c > index af3b22a..039e178 100644 > --- a/drivers/of/base.c > +++ b/drivers/of/base.c > @@ -670,6 +670,64 @@ struct device_node *of_find_node_by_phandle(phandle handle) > } > EXPORT_SYMBOL(of_find_node_by_phandle); > > +#define of_property_read_array(_np, _pname, _out, _sz) \ > + struct property *_prop = of_find_property(_np, _pname, NULL); \ > + const __be32 *_val; \ > + \ > + if (!_prop) \ > + return -EINVAL; \ > + if (!_prop->value) \ > + return -ENODATA; \ > + if ((_sz * sizeof(*_out)) > _prop->length) \ > + return -EOVERFLOW; \ > + \ > + _val = _prop->value; \ > + while (_sz--) \ > + *_out++ = (typeof(*_out))be32_to_cpup(_val++); \ This will not work. You are incrementing _out by 1, 2, or 4 bytes, but _val is always incremented by 4 bytes. According to the dtc commit adding this feature, the values are packed: With this patch the following property assignment: property = /bits/ 16 <0x1234 0x5678 0x0 0xffff>; is equivalent to: property = <0x12345678 0x0000ffff>; > + return 0; > + > +/** > + * 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. > + * Missing sz > + * 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. > + * > + * 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) > +{ > + of_property_read_array(np, propname, out_values, sz); > +} > +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. > + * Ditto. > + * 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. > + * > + * 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) > +{ > + of_property_read_array(np, propname, out_values, sz); > +} > +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. > @@ -689,20 +747,7 @@ int of_property_read_u32_array(const struct device_node *np, > const char *propname, u32 *out_values, > size_t sz) > { > - struct property *prop = of_find_property(np, propname, NULL); > - const __be32 *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++ = be32_to_cpup(val++); > - return 0; > + of_property_read_array(np, propname, out_values, sz); > } > EXPORT_SYMBOL_GPL(of_property_read_u32_array); > > diff --git a/include/linux/of.h b/include/linux/of.h > index 72843b7..e2d9b40 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, > @@ -357,6 +361,18 @@ 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) > @@ -463,6 +479,20 @@ 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) > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/