From mboxrd@z Thu Jan 1 00:00:00 1970 From: rnayak@ti.com (Rajendra Nayak) Date: Wed, 20 Mar 2013 15:43:36 +0530 Subject: [RESEND PATCH 1/3] clk: Remove _clk_reparent from API and restructure code In-Reply-To: References: <1363116050-3882-1-git-send-email-ulf.hansson@stericsson.com> <1363116050-3882-2-git-send-email-ulf.hansson@stericsson.com> <20130319212053.8663.63425@quantum> Message-ID: <51498BD0.7010508@ti.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Wednesday 20 March 2013 03:15 PM, Ulf Hansson wrote: > On 19 March 2013 22:20, Mike Turquette wrote: >> Quoting Ulf Hansson (2013-03-12 12:20:48) >>> From: Ulf Hansson >>> >>> There shall be no reason for keeping this API available for clock >>> providers. So we remove it from the API and restrcuture the code so >>> for example the COMMON_CLK_DEBUG part is separated. >>> >> >> Hi Ulf, >> >> There is one reason to keep this api. OMAP currently uses it to change >> the parent of a PLL during .set_rate. This is kind of a legacy >> mechanism however, and the reentrancy series I posted actually takes >> care of this one corner case: >> http://article.gmane.org/gmane.linux.kernel/1448449 > > Hi Mike, > > It was a while ago I created this patch, so I guess this has beed > merged without me noticing, sorry. > >> >> Let me see how the OMAP folks feel about taking that patch in, which >> eliminates the only external user of the API. +Rajendra & Benoit >> > > I have no problem rebasing the patch and keep the API, if that is the > easiest way forward. Ulf, It would be good if you could keep the api for now. I seemed to have missed out on Mikes patch getting rid of the the api from OMAP PLL .set_rate. I will take a stab at that to get rid of that api along with the other OMAP only things that exist today as part of Common clk. regards, Rajendra > Although, I guess in the end you want to remove these kind of internal > clk API functions. So, if we get ack from Rajendra & Benoit, it is > better to remove the API right? > > Kind regards > Ulf Hansson > >> Thanks, >> Mike >> >>> This patch will also make it possible to hold the spinlock over the >>> actual update of the clock tree topology, which could not be done >>> before when both debugfs updates and clock rate updates was done >>> within the same function. >>> >>> Signed-off-by: Ulf Hansson >>> --- >>> drivers/clk/clk.c | 82 ++++++++++++++++++++++++------------------ >>> include/linux/clk-provider.h | 1 - >>> 2 files changed, 48 insertions(+), 35 deletions(-) >>> >>> diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c >>> index 593a2e4..2e10cc1 100644 >>> --- a/drivers/clk/clk.c >>> +++ b/drivers/clk/clk.c >>> @@ -284,6 +284,39 @@ out: >>> } >>> >>> /** >>> + * clk_debug_reparent - reparent clk node in the debugfs clk tree >>> + * @clk: the clk being reparented >>> + * @new_parent: the new clk parent, may be NULL >>> + * >>> + * Rename clk entry in the debugfs clk tree if debugfs has been >>> + * initialized. Otherwise it bails out early since the debugfs clk tree >>> + * will be created lazily by clk_debug_init as part of a late_initcall. >>> + * >>> + * Caller must hold prepare_lock. >>> + */ >>> +static void clk_debug_reparent(struct clk *clk, struct clk *new_parent) >>> +{ >>> + struct dentry *d; >>> + struct dentry *new_parent_d; >>> + >>> + if (!inited) >>> + return; >>> + >>> + if (new_parent) >>> + new_parent_d = new_parent->dentry; >>> + else >>> + new_parent_d = orphandir; >>> + >>> + d = debugfs_rename(clk->dentry->d_parent, clk->dentry, >>> + new_parent_d, clk->name); >>> + if (d) >>> + clk->dentry = d; >>> + else >>> + pr_debug("%s: failed to rename debugfs entry for %s\n", >>> + __func__, clk->name); >>> +} >>> + >>> +/** >>> * clk_debug_init - lazily create the debugfs clk tree visualization >>> * >>> * clks are often initialized very early during boot before memory can >>> @@ -338,6 +371,9 @@ static int __init clk_debug_init(void) >>> late_initcall(clk_debug_init); >>> #else >>> static inline int clk_debug_register(struct clk *clk) { return 0; } >>> +static inline void clk_debug_reparent(struct clk *clk, struct clk *new_parent) >>> +{ >>> +} >>> #endif >>> >>> /* caller must hold prepare_lock */ >>> @@ -1179,16 +1215,8 @@ out: >>> return ret; >>> } >>> >>> -void __clk_reparent(struct clk *clk, struct clk *new_parent) >>> +static void clk_reparent(struct clk *clk, struct clk *new_parent) >>> { >>> -#ifdef CONFIG_COMMON_CLK_DEBUG >>> - struct dentry *d; >>> - struct dentry *new_parent_d; >>> -#endif >>> - >>> - if (!clk || !new_parent) >>> - return; >>> - >>> hlist_del(&clk->child_node); >>> >>> if (new_parent) >>> @@ -1196,28 +1224,7 @@ void __clk_reparent(struct clk *clk, struct clk *new_parent) >>> else >>> hlist_add_head(&clk->child_node, &clk_orphan_list); >>> >>> -#ifdef CONFIG_COMMON_CLK_DEBUG >>> - if (!inited) >>> - goto out; >>> - >>> - if (new_parent) >>> - new_parent_d = new_parent->dentry; >>> - else >>> - new_parent_d = orphandir; >>> - >>> - d = debugfs_rename(clk->dentry->d_parent, clk->dentry, >>> - new_parent_d, clk->name); >>> - if (d) >>> - clk->dentry = d; >>> - else >>> - pr_debug("%s: failed to rename debugfs entry for %s\n", >>> - __func__, clk->name); >>> -out: >>> -#endif >>> - >>> clk->parent = new_parent; >>> - >>> - __clk_recalc_rates(clk, POST_RATE_CHANGE); >>> } >>> >>> static int __clk_set_parent(struct clk *clk, struct clk *parent) >>> @@ -1329,7 +1336,9 @@ int clk_set_parent(struct clk *clk, struct clk *parent) >>> } >>> >>> /* propagate rate recalculation downstream */ >>> - __clk_reparent(clk, parent); >>> + clk_reparent(clk, parent); >>> + clk_debug_reparent(clk, parent); >>> + __clk_recalc_rates(clk, POST_RATE_CHANGE); >>> >>> out: >>> mutex_unlock(&prepare_lock); >>> @@ -1453,14 +1462,19 @@ int __clk_init(struct device *dev, struct clk *clk) >>> hlist_for_each_entry_safe(orphan, tmp, tmp2, &clk_orphan_list, child_node) { >>> if (orphan->ops->get_parent) { >>> i = orphan->ops->get_parent(orphan->hw); >>> - if (!strcmp(clk->name, orphan->parent_names[i])) >>> - __clk_reparent(orphan, clk); >>> + if (!strcmp(clk->name, orphan->parent_names[i])) { >>> + clk_reparent(orphan, clk); >>> + clk_debug_reparent(orphan, clk); >>> + __clk_recalc_rates(orphan, POST_RATE_CHANGE); >>> + } >>> continue; >>> } >>> >>> for (i = 0; i < orphan->num_parents; i++) >>> if (!strcmp(clk->name, orphan->parent_names[i])) { >>> - __clk_reparent(orphan, clk); >>> + clk_reparent(orphan, clk); >>> + clk_debug_reparent(orphan, clk); >>> + __clk_recalc_rates(orphan, POST_RATE_CHANGE); >>> break; >>> } >>> } >>> diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h >>> index 4989b8a..87a7c2c 100644 >>> --- a/include/linux/clk-provider.h >>> +++ b/include/linux/clk-provider.h >>> @@ -359,7 +359,6 @@ struct clk *__clk_lookup(const char *name); >>> */ >>> int __clk_prepare(struct clk *clk); >>> void __clk_unprepare(struct clk *clk); >>> -void __clk_reparent(struct clk *clk, struct clk *new_parent); >>> unsigned long __clk_round_rate(struct clk *clk, unsigned long rate); >>> >>> struct of_device_id; >>> -- >>> 1.7.10