Grant Likely <grant.likely@xxxxxxxxxx> wrote @ Thu, 12 Dec 2013 12:34:17 +0100: > On Wed, 11 Dec 2013 14:33:38 +0100, Hiroshi Doyu <hdoyu@xxxxxxxxxx> wrote: > > Hi Grant, > > > > Grant Likely <grant.likely@xxxxxxxxxx> wrote @ Wed, 11 Dec 2013 14:28:45 +0100: > > > > > On Thu, 21 Nov 2013 11:57:00 -0700, Stephen Warren <swarren@xxxxxxxxxxxxx> wrote: > > > > On 11/21/2013 10:17 AM, Hiroshi Doyu wrote: > > > > > Iterating over a property containing a list of phandles with arguments > > > > > is a common operation for device drivers. This patch adds a new > > > > > of_property_for_each_phandle_with_args() macro to make the iteration > > > > > simpler. > > > > > > > > > > Signed-off-by: Hiroshi Doyu <hdoyu@xxxxxxxxxx> > > > > > --- > > > > > v6+: > > > > > Use the description, which Grant Likely proposed, to be full enough > > > > > that a future reader can figure out why a patch was written. > > > > > http://lists.linuxfoundation.org/pipermail/iommu/2013-November/007062.html > > ... > > > > > That's right, I forgot I said that. Yes please fix the implementation. > > > > Here's the latest. I'll include this with the next v7 series. > > > > Can I get your Acked-by with this? > > > > --8<---- > > > > From 8f7c0404aa68f0e8dbe0babc240590f6528ecc1f Mon Sep 17 00:00:00 2001 > > From: Hiroshi Doyu <hdoyu@xxxxxxxxxx> > > Date: Fri, 15 Nov 2013 10:52:53 +0200 > > Subject: [PATCH] of: introduce of_property_for_each_phandle_with_args() > > > > Iterating over a property containing a list of phandles with arguments > > is a common operation for device drivers. This patch adds a new > > of_property_for_each_phandle_with_args() macro to make the iteration > > simpler. > > > > Signed-off-by: Hiroshi Doyu <hdoyu@xxxxxxxxxx> > > Cc: Rob Herring <robherring2@xxxxxxxxx> > > --- > > v7: > > Fixed some minors pointed by Rob and Stephen. > > > > v6++++: > > Iterate without intrducing a new struct. > > > > v6+++: > > Introduced a new struct "of_phandle_iter" to keep the state when > > iterating over the list. > > > > v6++: > > Optimized to avoid O(n^2), suggested by Stephen Warren. > > http://lists.linuxfoundation.org/pipermail/iommu/2013-November/007066.html > > > > I didn't introduce any struct to hold params and state here. > > > > v6+: > > Use the description, which Grant Likely proposed, to be full enough > > that a future reader can figure out why a patch was written. > > > > v5: > > New patch for v5. > > > > Signed-off-by: Hiroshi Doyu <hdoyu@xxxxxxxxxx> > > --- > > drivers/of/base.c | 46 ++++++++++++++++++++++++++++++++++++++++++++++ > > include/linux/of.h | 32 ++++++++++++++++++++++++++++++++ > > 2 files changed, 78 insertions(+) > > > > diff --git a/drivers/of/base.c b/drivers/of/base.c > > index f807d0e..cd4ab05 100644 > > --- a/drivers/of/base.c > > +++ b/drivers/of/base.c > > @@ -1201,6 +1201,52 @@ void of_print_phandle_args(const char *msg, const struct of_phandle_args *args) > > printk("\n"); > > } > > > > +const __be32 *of_phandle_iter_next(const char *cells_name, int cell_count, > > + const __be32 *cur, const __be32 *end, > > + struct of_phandle_args *out_args) > > Having to pass in cells_name, cell_count, cur and end each time seems a > little odd. Can a state structure be used instead? > > struct of_phandle_iter_state { > const char *cells_name; > int cells_count; > const __be32 *cur; > const __be32 *end; > struct of_phandle_args out_args; > } > > Make the caller provide one of those and fill it in with the init > function. I rewrote this a few times and so now I have a few version of this implementations :-) The above proposal is similar to the version v6+++ mentioned in the above patch note: > > v6+++: > > Introduced a new struct "of_phandle_iter" to keep the state when > > iterating over the list. which is: [RFC][PATCHv6+++ 01/13] of: introduce of_property_for_earch_phandle_with_args() http://lists.linuxfoundation.org/pipermail/iommu/2013-November/007087.html Stephen seemed to prefer the version without state struct. I like the idea to not pass the same arguments repeatly. Instead, wrapping them in a struct with state may look better. So if Stephen agrees, I'll rewrite the version with state struct again. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
