On 13.9.2018 20:53, Rob Herring wrote: > 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. ok. I have added that function. Also I realized that this function should return return value to let users know if this function is not returning proper values. I have updated this in v2. > > With that, I'm assuming this is going with your serial patches: yes that will be the best because serial driver is only one user. > > Reviewed-by: Rob Herring <robh@xxxxxxxxxx> Added to v2. If you don't agree with also adding return value please let me know. Thanks, Michal
