From mboxrd@z Thu Jan 1 00:00:00 1970 From: Frank Rowand Subject: Re: [RFC/PATCH] dt: Add of_device_compatible_match() Date: Thu, 7 Jul 2016 09:42:54 -0700 Message-ID: <577E868E.30702@gmail.com> References: <1466981246.20278.27.camel@kernel.crashing.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1466981246.20278.27.camel-XVmvHMARGAS8U2dJNN8I7kB+6BGkLq7r@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Benjamin Herrenschmidt , devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Cc: Rob Herring List-Id: devicetree@vger.kernel.org On 06/26/16 15:47, Benjamin Herrenschmidt wrote: > This provides an equivalent of of_fdt_match() for non-flat trees. > > This is more practical than matching an array of of_device_id structs > when converting a bunch of existing users of of_fdt_match(). > > Signed-off-by: Benjamin Herrenschmidt > --- > > This is a pre-requisite for some work I'm doing to move the platform > identification in arch/powerpc until after we have unflattened the > device-tree. Rewriting all those lists as of_device_id's would be > significantly cumbersome. > > Note: untested other than it compiles. I want an agreement on the > interface ASAP since the conversion of all the platforms is a burden > I'd like to avoid doing twice. > > diff --git a/drivers/of/base.c b/drivers/of/base.c > index ebf84e3..429c594 100644 > --- a/drivers/of/base.c > +++ b/drivers/of/base.c > @@ -493,6 +493,28 @@ int of_device_is_compatible(const struct device_node *device, > } > EXPORT_SYMBOL(of_device_is_compatible); > > +/** Checks if the device is compatible with any of the entries in > + * a NULL terminated array of strings. Returns the best match > + * score or 0. > + */ > +int of_device_compatible_match(struct device_node *device, > + const char *const *compat) > +{ > + unsigned int tmp, score = 0; > + > + if (!compat) > + return 0; > + > + while (*compat) { > + tmp = of_device_is_compatible(device, *compat); > + if (tmp && (score == 0 || (tmp < score))) > + score = tmp; > + compat++; > + } > + > + return score; > +} > + of_device_is_compatible() returns a higher value for a better match. of_fdt_match() returns a lower value for a better match. So checking for (tmp < score) will give you the opposite of what you want. And if you are replacing of_fdt_match() with of_device_compatible_match(), the caller will have the expectation that a smaller score is a better match. > /** > * of_machine_is_compatible - Test root of device tree for a given compatible value > * @compat: compatible string to look for in root node's compatible property. > diff --git a/include/linux/of.h b/include/linux/of.h > index 74eb28c..33c184d 100644 > --- a/include/linux/of.h > +++ b/include/linux/of.h > @@ -324,6 +324,8 @@ extern int of_property_read_string_helper(const struct device_node *np, > const char **out_strs, size_t sz, int index); > extern int of_device_is_compatible(const struct device_node *device, > const char *); > +extern int of_device_compatible_match(struct device_node *device, > + const char *const *compat); > extern bool of_device_is_available(const struct device_node *device); > extern bool of_device_is_big_endian(const struct device_node *device); > extern const void *of_get_property(const struct device_node *node, > -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html