From mboxrd@z Thu Jan 1 00:00:00 1970 From: Heiko =?ISO-8859-1?Q?St=FCbner?= Subject: Re: [PATCH v4] of: add functions to count number of elements in a property Date: Sat, 18 Jan 2014 16:28:51 +0100 Message-ID: <1812408.EavpSnUyy3@phil> References: <27256277.YJ687suYy5@phil> <5115255.DrcMbtXc1P@phil> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Rob Herring Cc: Mark Rutland , Pawel Moll , "linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org" , "grant.likely-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org" , "devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Stephen Warren , Ian Campbell List-Id: devicetree@vger.kernel.org Am Samstag, 18. Januar 2014, 09:07:30 schrieb Rob Herring: > On Sat, Jan 18, 2014 at 6:02 AM, Heiko St=FCbner wr= ote: > > The need to know the number of array elements in a property is > > a common pattern. To prevent duplication of open-coded implementati= ons > > add a helper static function that also centralises strict sanity > > checking and DTB format details, as well as a set of wrapper functi= ons > > for u8, u16, u32 and u64. > >=20 > > Suggested-by: Mark Rutland > > Signed-off-by: Heiko Stuebner > > --- >=20 > Looks good. Do you plan to convert some users to use this? My plan at the moment was to "just" use it for my mmio-sram-reserve stu= ff -=20 just wanted to make sure that this change is sane, before having to sen= t the=20 whole thing for each iteration. I haven't yet looked where the other users, that Mark mentioned, are at= :-) Heiko > > changes since v3: > > address more comments from Rob Herring > > - export the base function and inline the type-specific wrappers > > changes since v2: > > address more comments from Mark Rutland > > - switch to of_property_count_elems_of_size > > - use full_name instead of name in error message > > changes since v1: > > address comments from Rob Herring and Mark Rutland: > > - provide a helper and a set of wrappers for u8-u64 > > - get rid of extra len variable, prop->length is enough > > - include node name in error message > >=20 > > Mark, does your Reviewed-by holds for this variant too? > >=20 > > drivers/of/base.c | 32 ++++++++++++++++++++++ > > include/linux/of.h | 76 > > ++++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files chang= ed, > > 108 insertions(+) > >=20 > > diff --git a/drivers/of/base.c b/drivers/of/base.c > > index f807d0e..21646c0 100644 > > --- a/drivers/of/base.c > > +++ b/drivers/of/base.c > > @@ -862,6 +862,38 @@ struct device_node *of_find_node_by_phandle(ph= andle > > handle)>=20 > > EXPORT_SYMBOL(of_find_node_by_phandle); > > =20 > > /** > >=20 > > + * of_property_count_elems_of_size - Count the number of elements = in a > > property + * > > + * @np: device node from which the property value i= s to be > > read. + * @propname: name of the property to be searched. > > + * @elem_size: size of the individual element > > + * > > + * Search for a property in a device node and count the number of > > elements of + * size elem_size in it. Returns number of elements on > > sucess, -EINVAL if the + * property does not exist or its length do= es not > > match a multiple of u16 and + * -ENODATA if the property does not h= ave a > > value. > > + */ > > +int of_property_count_elems_of_size(const struct device_node *np, > > + const char *propname, int elem_size= ) > > +{ > > + struct property *prop =3D of_find_property(np, propname, NU= LL); > > + > > + if (!prop) > > + return -EINVAL; > > + if (!prop->value) > > + return -ENODATA; > > + > > + if (prop->length % elem_size !=3D 0) { > > + pr_err("size of %s in node %s is not a multiple of = %d\n", > > + propname, np->full_name, elem_size); > > + return -EINVAL; > > + } > > + > > + return prop->length / elem_size; > > +} > > +EXPORT_SYMBOL_GPL(of_property_count_elems_of_size); > > + > > +/** > >=20 > > * of_find_property_value_of_size > > * > > * @np: device node from which the property value i= s to be > > read.>=20 > > diff --git a/include/linux/of.h b/include/linux/of.h > > index 276c546..293920d 100644 > > --- a/include/linux/of.h > > +++ b/include/linux/of.h > > @@ -250,6 +250,8 @@ extern struct device_node *of_find_node_with_pr= operty( > >=20 > > extern struct property *of_find_property(const struct device_node = *np, > > =20 > > const char *name, > > int *lenp); > >=20 > > +extern int of_property_count_elems_of_size(const struct device_nod= e *np, > > + const char *propname, int elem_size= ); > >=20 > > extern int of_property_read_u32_index(const struct device_node *np= , > > =20 > > const char *propname, > > u32 index, u32 *out_value); > >=20 > > @@ -426,6 +428,12 @@ static inline struct device_node > > *of_find_compatible_node(>=20 > > return NULL; > > =20 > > } > >=20 > > +static inline int of_property_count_elems_of_size(const struct > > device_node *np, + const char *propname, int > > elem_size) > > +{ > > + return -ENOSYS; > > +} > > + > >=20 > > static inline int of_property_read_u32_index(const struct device_n= ode > > *np, > > =20 > > const char *propname, u32 index, u32 *out_v= alue) > > =20 > > { > >=20 > > @@ -565,6 +573,74 @@ static inline int of_node_to_nid(struct device= _node > > *device) { return 0; }>=20 > > #endif > > =20 > > /** > >=20 > > + * of_property_count_u8_elems - Count the number of u8 elements in= a > > property + * > > + * @np: device node from which the property value i= s to be > > read. + * @propname: name of the property to be searched. > > + * > > + * Search for a property in a device node and count the number of = u8 > > elements + * in it. Returns number of elements on sucess, -EINVAL i= f the > > property does + * not exist or its length does not match a multiple= of u8 > > and -ENODATA if the + * property does not have a value. > > + */ > > +static inline int of_property_count_u8_elems(const struct device_n= ode > > *np, > > + const char *propname) > > +{ > > + return of_property_count_elems_of_size(np, propname, sizeof= (u8)); > > +} > > + > > +/** > > + * of_property_count_u16_elems - Count the number of u16 elements = in a > > property + * > > + * @np: device node from which the property value i= s to be > > read. + * @propname: name of the property to be searched. > > + * > > + * Search for a property in a device node and count the number of = u16 > > elements + * in it. Returns number of elements on sucess, -EINVAL i= f the > > property does + * not exist or its length does not match a multiple= of > > u16 and -ENODATA if the + * property does not have a value. > > + */ > > +static inline int of_property_count_u16_elems(const struct device_= node > > *np, + const char *propname) > > +{ > > + return of_property_count_elems_of_size(np, propname, sizeof= (u16)); > > +} > > + > > +/** > > + * of_property_count_u32_elems - Count the number of u32 elements = in a > > property + * > > + * @np: device node from which the property value i= s to be > > read. + * @propname: name of the property to be searched. > > + * > > + * Search for a property in a device node and count the number of = u32 > > elements + * in it. Returns number of elements on sucess, -EINVAL i= f the > > property does + * not exist or its length does not match a multiple= of > > u32 and -ENODATA if the + * property does not have a value. > > + */ > > +static inline int of_property_count_u32_elems(const struct device_= node > > *np, + const char *propname) > > +{ > > + return of_property_count_elems_of_size(np, propname, sizeof= (u32)); > > +} > > + > > +/** > > + * of_property_count_u64_elems - Count the number of u64 elements = in a > > property + * > > + * @np: device node from which the property value i= s to be > > read. + * @propname: name of the property to be searched. > > + * > > + * Search for a property in a device node and count the number of = u64 > > elements + * in it. Returns number of elements on sucess, -EINVAL i= f the > > property does + * not exist or its length does not match a multiple= of > > u64 and -ENODATA if the + * property does not have a value. > > + */ > > +static inline int of_property_count_u64_elems(const struct device_= node > > *np, + const char *propname) > > +{ > > + return of_property_count_elems_of_size(np, propname, sizeof= (u64)); > > +} > > + > > +/** > >=20 > > * of_property_read_bool - Findfrom a property > > * @np: device node from which the property value i= s to be > > read. * @propname: name of the property to be searched. > >=20 > > -- > > 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe devicetree" i= n the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html