On Mon, Sep 3, 2018 at 8:14 AM Michal Simek <michal.simek@xxxxxxxxxx> wrote: > > The function travers the lookup table to check if the request alias > id is compatible with the device driver match structure. > This function will be used by serial drivers to check if requested alias > is allocated or free to use. > > Signed-off-by: Michal Simek <michal.simek@xxxxxxxxxx> > --- > > Based on discussion with Rob > https://lkml.org/lkml/2018/4/27/397 > nbits is passed to the function not to limit only to 32/64bit fields. > > --- > drivers/of/base.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++ > include/linux/of.h | 3 +++ > 2 files changed, 51 insertions(+) > > diff --git a/drivers/of/base.c b/drivers/of/base.c > index 466e3c8582f0..236a85d69957 100644 > --- a/drivers/of/base.c > +++ b/drivers/of/base.c > @@ -16,6 +16,7 @@ > > #define pr_fmt(fmt) "OF: " fmt > > +#include <linux/bitmap.h> > #include <linux/console.h> > #include <linux/ctype.h> > #include <linux/cpu.h> > @@ -1893,6 +1894,53 @@ int of_alias_get_id(struct device_node *np, const char *stem) > EXPORT_SYMBOL_GPL(of_alias_get_id); > > /** > + * of_alias_get_alias_list - Get alias list for the given device driver > + * @matches: Array of OF device match structures to search in > + * @stem: Alias stem of the given device_node > + * @bitmap: Bitmap field pointer > + * @nbits: Maximum number of alias ID which can be recorded it bitmap > + * > + * The function travels the lookup table to record alias ids for the given > + * device match structures and alias stem. > + */ > +void of_alias_get_alias_list(const struct of_device_id *matches, > + const char *stem, unsigned long *bitmap, > + unsigned int nbits) > +{ > + struct alias_prop *app; > + > + /* Zero bitmap field to make sure that all the time it is clean */ > + bitmap_zero(bitmap, nbits); > + > + mutex_lock(&of_mutex); > + pr_debug("%s: Looking for stem: %s\n", __func__, stem); > + list_for_each_entry(app, &aliases_lookup, link) { > + pr_debug("%s: stem: %s, id: %d\n", > + __func__, app->stem, app->id); > + > + if (strcmp(app->stem, stem) != 0) { > + pr_debug("%s: stem comparison doesn't passed %s\n", > + __func__, app->stem); > + continue; > + } > + > + if (app->id >= nbits) { > + pr_debug("%s: ID %d greater then bitmap field %d\n", > + __func__, app->id, nbits); > + continue; > + } > + > + if (of_match_node(matches, app->np)) { > + pr_debug("%s: Allocated ID %d\n", __func__, app->id); > + set_bit(app->id, bitmap); > + } > + /* Alias exist but it not compatible with matches */ > + } > + mutex_unlock(&of_mutex); > +} > +EXPORT_SYMBOL_GPL(of_alias_get_alias_list); > + > +/** > * of_alias_get_highest_id - Get highest alias id for the given stem > * @stem: Alias stem to be examined > * > diff --git a/include/linux/of.h b/include/linux/of.h > index 4d25e4f952d9..e474710e3930 100644 > --- a/include/linux/of.h > +++ b/include/linux/of.h > @@ -387,6 +387,9 @@ extern int of_phandle_iterator_args(struct of_phandle_iterator *it, > extern void of_alias_scan(void * (*dt_alloc)(u64 size, u64 align)); > extern int of_alias_get_id(struct device_node *np, const char *stem); > extern int of_alias_get_highest_id(const char *stem); > +extern void of_alias_get_alias_list(const struct of_device_id *matches, > + const char *stem, unsigned long *bitmap, > + unsigned int nbits); You should go ahead and add an empty function too as the other 2 alias functions have one. With that, I'm assuming this is going with your serial patches: Reviewed-by: Rob Herring <robh@xxxxxxxxxx>
