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authorLinus Torvalds <torvalds@linux-foundation.org>2016-03-23 16:06:45 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2016-03-23 16:06:45 +0300
commit33c1f638a0feda92ffcb507c302482a5e6158a87 (patch)
tree57d70d2e0b56d38bd295fe439294c3c8739f4130 /drivers/clk/clk.c
parenta24e3d414e59ac76566dedcad1ed1d319a93ec14 (diff)
parent4d3ac6662452060721599a3392bc2f524af984cb (diff)
downloadlinux-33c1f638a0feda92ffcb507c302482a5e6158a87.tar.xz
Merge tag 'clk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux
Pull clk updates from Stephen Boyd: "The clk changes for this release cycle are mostly dominated by new device support in terms of LoC, but there has been some cleanup in the core as well as the usual minor clk additions to various drivers. Core: - parent tracking has been simplified - CLK_IS_ROOT is now a no-op flag, cleaning up drivers has started - of_clk_init() doesn't consider disabled DT nodes anymore - clk_unregister() had an error path bug squashed - of_clk_get_parent_count() has been fixed to only return unsigned ints - HAVE_MACH_CLKDEV is removed now that the last arch user (ARM) is gone New Drivers: - NXP LPC18xx creg - QCOM IPQ4019 GCC - TI dm814x ADPLL - i.MX6QP Updates: - Cyngus audio clks found on Broadcom iProc devices - Non-critical fixes for BCM2385 PLLs - Samsung exynos5433 updates for clk id errors, HDMI support, suspend/resume simplifications - USB, CAN, LVDS, and FCP clks on shmobile devices - sunxi got support for more clks on new SoCs and went through a minor refactoring/rewrite to use a simpler factor clk construct - rockchip added some more clk ids and added suport for fraction dividers - QCOM GDSCs in msm8996 - A new devm helper to make adding custom actions simpler (acked by Greg)" * tag 'clk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux: (197 commits) clk: bcm2835: fix check of error code returned by devm_ioremap_resource() clk: renesas: div6: use RENESAS for #define clk: renesas: Rename header file renesas.h clk: max77{686,802}: Remove CLK_IS_ROOT clk: versatile: Remove CLK_IS_ROOT clk: sunxi: Remove use of variable length array clk: fixed-rate: Remove CLK_IS_ROOT clk: qcom: Remove CLK_IS_ROOT doc: dt: add documentation for lpc1850-creg-clk driver clk: add lpc18xx creg clk driver clk: lpc32xx: fix compilation warning clk: xgene: Add missing parenthesis when clearing divider value clk: mb86s7x: Remove CLK_IS_ROOT clk: x86: Remove clkdev.h and clk.h includes clk: x86: Remove CLK_IS_ROOT clk: mvebu: Remove CLK_IS_ROOT clk: renesas: move drivers to renesas directory clk: si5{14,351,70}: Remove CLK_IS_ROOT clk: scpi: Remove CLK_IS_ROOT clk: s2mps11: Remove CLK_IS_ROOT ...
Diffstat (limited to 'drivers/clk/clk.c')
-rw-r--r--drivers/clk/clk.c221
1 files changed, 80 insertions, 141 deletions
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index b4db67a446c8..fb74dc1f7520 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -350,13 +350,12 @@ static struct clk_core *clk_core_get_parent_by_index(struct clk_core *core,
{
if (!core || index >= core->num_parents)
return NULL;
- else if (!core->parents)
- return clk_core_lookup(core->parent_names[index]);
- else if (!core->parents[index])
- return core->parents[index] =
- clk_core_lookup(core->parent_names[index]);
- else
- return core->parents[index];
+
+ if (!core->parents[index])
+ core->parents[index] =
+ clk_core_lookup(core->parent_names[index]);
+
+ return core->parents[index];
}
struct clk_hw *
@@ -386,7 +385,7 @@ static unsigned long clk_core_get_rate_nolock(struct clk_core *core)
ret = core->rate;
- if (core->flags & CLK_IS_ROOT)
+ if (!core->num_parents)
goto out;
if (!core->parent)
@@ -1067,30 +1066,12 @@ static int clk_fetch_parent_index(struct clk_core *core,
{
int i;
- if (!core->parents) {
- core->parents = kcalloc(core->num_parents,
- sizeof(struct clk *), GFP_KERNEL);
- if (!core->parents)
- return -ENOMEM;
- }
-
- /*
- * find index of new parent clock using cached parent ptrs,
- * or if not yet cached, use string name comparison and cache
- * them now to avoid future calls to clk_core_lookup.
- */
- for (i = 0; i < core->num_parents; i++) {
- if (core->parents[i] == parent)
- return i;
-
- if (core->parents[i])
- continue;
+ if (!parent)
+ return -EINVAL;
- if (!strcmp(core->parent_names[i], parent->name)) {
- core->parents[i] = clk_core_lookup(parent->name);
+ for (i = 0; i < core->num_parents; i++)
+ if (clk_core_get_parent_by_index(core, i) == parent)
return i;
- }
- }
return -EINVAL;
}
@@ -1677,56 +1658,14 @@ struct clk *clk_get_parent(struct clk *clk)
}
EXPORT_SYMBOL_GPL(clk_get_parent);
-/*
- * .get_parent is mandatory for clocks with multiple possible parents. It is
- * optional for single-parent clocks. Always call .get_parent if it is
- * available and WARN if it is missing for multi-parent clocks.
- *
- * For single-parent clocks without .get_parent, first check to see if the
- * .parents array exists, and if so use it to avoid an expensive tree
- * traversal. If .parents does not exist then walk the tree.
- */
static struct clk_core *__clk_init_parent(struct clk_core *core)
{
- struct clk_core *ret = NULL;
- u8 index;
+ u8 index = 0;
- /* handle the trivial cases */
+ if (core->num_parents > 1 && core->ops->get_parent)
+ index = core->ops->get_parent(core->hw);
- if (!core->num_parents)
- goto out;
-
- if (core->num_parents == 1) {
- if (IS_ERR_OR_NULL(core->parent))
- core->parent = clk_core_lookup(core->parent_names[0]);
- ret = core->parent;
- goto out;
- }
-
- if (!core->ops->get_parent) {
- WARN(!core->ops->get_parent,
- "%s: multi-parent clocks must implement .get_parent\n",
- __func__);
- goto out;
- }
-
- /*
- * Do our best to cache parent clocks in core->parents. This prevents
- * unnecessary and expensive lookups. We don't set core->parent here;
- * that is done by the calling function.
- */
-
- index = core->ops->get_parent(core->hw);
-
- if (!core->parents)
- core->parents =
- kcalloc(core->num_parents, sizeof(struct clk *),
- GFP_KERNEL);
-
- ret = clk_core_get_parent_by_index(core, index);
-
-out:
- return ret;
+ return clk_core_get_parent_by_index(core, index);
}
static void clk_core_reparent(struct clk_core *core,
@@ -1809,13 +1748,13 @@ static int clk_core_set_parent(struct clk_core *core, struct clk_core *parent)
/* try finding the new parent index */
if (parent) {
p_index = clk_fetch_parent_index(core, parent);
- p_rate = parent->rate;
if (p_index < 0) {
pr_debug("%s: clk %s can not be parent of clk %s\n",
__func__, parent->name, core->name);
ret = p_index;
goto out;
}
+ p_rate = parent->rate;
}
/* propagate PRE_RATE_CHANGE notifications */
@@ -1902,6 +1841,10 @@ int clk_set_phase(struct clk *clk, int degrees)
clk_prepare_lock();
+ /* bail early if nothing to do */
+ if (degrees == clk->core->phase)
+ goto out;
+
trace_clk_set_phase(clk->core, degrees);
if (clk->core->ops->set_phase)
@@ -1912,6 +1855,7 @@ int clk_set_phase(struct clk *clk, int degrees)
if (!ret)
clk->core->phase = degrees;
+out:
clk_prepare_unlock();
return ret;
@@ -2218,7 +2162,7 @@ unlock:
*
* Dynamically removes a clk and all its child nodes from the
* debugfs clk directory if clk->dentry points to debugfs created by
- * clk_debug_register in __clk_init.
+ * clk_debug_register in __clk_core_init.
*/
static void clk_debug_unregister(struct clk_core *core)
{
@@ -2303,26 +2247,22 @@ static inline void clk_debug_unregister(struct clk_core *core)
#endif
/**
- * __clk_init - initialize the data structures in a struct clk
- * @dev: device initializing this clk, placeholder for now
- * @clk: clk being initialized
+ * __clk_core_init - initialize the data structures in a struct clk_core
+ * @core: clk_core being initialized
*
* Initializes the lists in struct clk_core, queries the hardware for the
* parent and rate and sets them both.
*/
-static int __clk_init(struct device *dev, struct clk *clk_user)
+static int __clk_core_init(struct clk_core *core)
{
int i, ret = 0;
struct clk_core *orphan;
struct hlist_node *tmp2;
- struct clk_core *core;
unsigned long rate;
- if (!clk_user)
+ if (!core)
return -EINVAL;
- core = clk_user->core;
-
clk_prepare_lock();
/* check to see if a clock with this name is already registered */
@@ -2337,22 +2277,29 @@ static int __clk_init(struct device *dev, struct clk *clk_user)
if (core->ops->set_rate &&
!((core->ops->round_rate || core->ops->determine_rate) &&
core->ops->recalc_rate)) {
- pr_warning("%s: %s must implement .round_rate or .determine_rate in addition to .recalc_rate\n",
- __func__, core->name);
+ pr_err("%s: %s must implement .round_rate or .determine_rate in addition to .recalc_rate\n",
+ __func__, core->name);
ret = -EINVAL;
goto out;
}
if (core->ops->set_parent && !core->ops->get_parent) {
- pr_warning("%s: %s must implement .get_parent & .set_parent\n",
- __func__, core->name);
+ pr_err("%s: %s must implement .get_parent & .set_parent\n",
+ __func__, core->name);
+ ret = -EINVAL;
+ goto out;
+ }
+
+ if (core->num_parents > 1 && !core->ops->get_parent) {
+ pr_err("%s: %s must implement .get_parent as it has multi parents\n",
+ __func__, core->name);
ret = -EINVAL;
goto out;
}
if (core->ops->set_rate_and_parent &&
!(core->ops->set_parent && core->ops->set_rate)) {
- pr_warn("%s: %s must implement .set_parent & .set_rate\n",
+ pr_err("%s: %s must implement .set_parent & .set_rate\n",
__func__, core->name);
ret = -EINVAL;
goto out;
@@ -2364,37 +2311,12 @@ static int __clk_init(struct device *dev, struct clk *clk_user)
"%s: invalid NULL in %s's .parent_names\n",
__func__, core->name);
- /*
- * Allocate an array of struct clk *'s to avoid unnecessary string
- * look-ups of clk's possible parents. This can fail for clocks passed
- * in to clk_init during early boot; thus any access to core->parents[]
- * must always check for a NULL pointer and try to populate it if
- * necessary.
- *
- * If core->parents is not NULL we skip this entire block. This allows
- * for clock drivers to statically initialize core->parents.
- */
- if (core->num_parents > 1 && !core->parents) {
- core->parents = kcalloc(core->num_parents, sizeof(struct clk *),
- GFP_KERNEL);
- /*
- * clk_core_lookup returns NULL for parents that have not been
- * clk_init'd; thus any access to clk->parents[] must check
- * for a NULL pointer. We can always perform lazy lookups for
- * missing parents later on.
- */
- if (core->parents)
- for (i = 0; i < core->num_parents; i++)
- core->parents[i] =
- clk_core_lookup(core->parent_names[i]);
- }
-
core->parent = __clk_init_parent(core);
/*
- * Populate core->parent if parent has already been __clk_init'd. If
- * parent has not yet been __clk_init'd then place clk in the orphan
- * list. If clk has set the CLK_IS_ROOT flag then place it in the root
+ * Populate core->parent if parent has already been clk_core_init'd. If
+ * parent has not yet been clk_core_init'd then place clk in the orphan
+ * list. If clk doesn't have any parents then place it in the root
* clk list.
*
* Every time a new clk is clk_init'd then we walk the list of orphan
@@ -2405,7 +2327,7 @@ static int __clk_init(struct device *dev, struct clk *clk_user)
hlist_add_head(&core->child_node,
&core->parent->children);
core->orphan = core->parent->orphan;
- } else if (core->flags & CLK_IS_ROOT) {
+ } else if (!core->num_parents) {
hlist_add_head(&core->child_node, &clk_root_list);
core->orphan = false;
} else {
@@ -2454,24 +2376,15 @@ static int __clk_init(struct device *dev, struct clk *clk_user)
core->rate = core->req_rate = rate;
/*
- * walk the list of orphan clocks and reparent any that are children of
- * this clock
+ * walk the list of orphan clocks and reparent any that newly finds a
+ * parent.
*/
hlist_for_each_entry_safe(orphan, tmp2, &clk_orphan_list, child_node) {
- if (orphan->num_parents && orphan->ops->get_parent) {
- i = orphan->ops->get_parent(orphan->hw);
- if (i >= 0 && i < orphan->num_parents &&
- !strcmp(core->name, orphan->parent_names[i]))
- clk_core_reparent(orphan, core);
- continue;
- }
+ struct clk_core *parent = __clk_init_parent(orphan);
- for (i = 0; i < orphan->num_parents; i++)
- if (!strcmp(core->name, orphan->parent_names[i])) {
- clk_core_reparent(orphan, core);
- break;
- }
- }
+ if (parent)
+ clk_core_reparent(orphan, parent);
+ }
/*
* optional platform-specific magic
@@ -2585,21 +2498,31 @@ struct clk *clk_register(struct device *dev, struct clk_hw *hw)
}
}
+ /* avoid unnecessary string look-ups of clk_core's possible parents. */
+ core->parents = kcalloc(core->num_parents, sizeof(*core->parents),
+ GFP_KERNEL);
+ if (!core->parents) {
+ ret = -ENOMEM;
+ goto fail_parents;
+ };
+
INIT_HLIST_HEAD(&core->clks);
hw->clk = __clk_create_clk(hw, NULL, NULL);
if (IS_ERR(hw->clk)) {
ret = PTR_ERR(hw->clk);
- goto fail_parent_names_copy;
+ goto fail_parents;
}
- ret = __clk_init(dev, hw->clk);
+ ret = __clk_core_init(core);
if (!ret)
return hw->clk;
__clk_free_clk(hw->clk);
hw->clk = NULL;
+fail_parents:
+ kfree(core->parents);
fail_parent_names_copy:
while (--i >= 0)
kfree_const(core->parent_names[i]);
@@ -2683,7 +2606,7 @@ void clk_unregister(struct clk *clk)
if (clk->core->ops == &clk_nodrv_ops) {
pr_err("%s: unregistered clock: %s\n", __func__,
clk->core->name);
- return;
+ goto unlock;
}
/*
* Assign empty clock ops for consumers that might still hold
@@ -2709,7 +2632,7 @@ void clk_unregister(struct clk *clk)
pr_warn("%s: unregistering prepared clock: %s\n",
__func__, clk->core->name);
kref_put(&clk->core->ref, __clk_release);
-
+unlock:
clk_prepare_unlock();
}
EXPORT_SYMBOL_GPL(clk_unregister);
@@ -3061,10 +2984,23 @@ struct clk *of_clk_get_from_provider(struct of_phandle_args *clkspec)
{
return __of_clk_get_from_provider(clkspec, NULL, __func__);
}
+EXPORT_SYMBOL_GPL(of_clk_get_from_provider);
-int of_clk_get_parent_count(struct device_node *np)
+/**
+ * of_clk_get_parent_count() - Count the number of clocks a device node has
+ * @np: device node to count
+ *
+ * Returns: The number of clocks that are possible parents of this node
+ */
+unsigned int of_clk_get_parent_count(struct device_node *np)
{
- return of_count_phandle_with_args(np, "clocks", "#clock-cells");
+ int count;
+
+ count = of_count_phandle_with_args(np, "clocks", "#clock-cells");
+ if (count < 0)
+ return 0;
+
+ return count;
}
EXPORT_SYMBOL_GPL(of_clk_get_parent_count);
@@ -3214,6 +3150,9 @@ void __init of_clk_init(const struct of_device_id *matches)
for_each_matching_node_and_match(np, matches, &match) {
struct clock_provider *parent;
+ if (!of_device_is_available(np))
+ continue;
+
parent = kzalloc(sizeof(*parent), GFP_KERNEL);
if (!parent) {
list_for_each_entry_safe(clk_provider, next,