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-rw-r--r--drivers/clk/Makefile2
-rw-r--r--drivers/clk/clk-bulk.c157
-rw-r--r--include/linux/clk.h111
3 files changed, 269 insertions, 1 deletions
diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index c19983afcb81..ed1e99f19ec3 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -1,5 +1,5 @@
# common clock types
-obj-$(CONFIG_HAVE_CLK) += clk-devres.o
+obj-$(CONFIG_HAVE_CLK) += clk-devres.o clk-bulk.o
obj-$(CONFIG_CLKDEV_LOOKUP) += clkdev.o
obj-$(CONFIG_COMMON_CLK) += clk.o
obj-$(CONFIG_COMMON_CLK) += clk-divider.o
diff --git a/drivers/clk/clk-bulk.c b/drivers/clk/clk-bulk.c
new file mode 100644
index 000000000000..c834f5abfc49
--- /dev/null
+++ b/drivers/clk/clk-bulk.c
@@ -0,0 +1,157 @@
+/*
+ * Copyright 2017 NXP
+ *
+ * Dong Aisheng <aisheng.dong@nxp.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/clk.h>
+#include <linux/device.h>
+#include <linux/export.h>
+
+void clk_bulk_put(int num_clks, struct clk_bulk_data *clks)
+{
+ while (--num_clks >= 0) {
+ clk_put(clks[num_clks].clk);
+ clks[num_clks].clk = NULL;
+ }
+}
+EXPORT_SYMBOL_GPL(clk_bulk_put);
+
+int __must_check clk_bulk_get(struct device *dev, int num_clks,
+ struct clk_bulk_data *clks)
+{
+ int ret;
+ int i;
+
+ for (i = 0; i < num_clks; i++)
+ clks[i].clk = NULL;
+
+ for (i = 0; i < num_clks; i++) {
+ clks[i].clk = clk_get(dev, clks[i].id);
+ if (IS_ERR(clks[i].clk)) {
+ ret = PTR_ERR(clks[i].clk);
+ dev_err(dev, "Failed to get clk '%s': %d\n",
+ clks[i].id, ret);
+ clks[i].clk = NULL;
+ goto err;
+ }
+ }
+
+ return 0;
+
+err:
+ clk_bulk_put(i, clks);
+
+ return ret;
+}
+EXPORT_SYMBOL(clk_bulk_get);
+
+#ifdef CONFIG_HAVE_CLK_PREPARE
+
+/**
+ * clk_bulk_unprepare - undo preparation of a set of clock sources
+ * @num_clks: the number of clk_bulk_data
+ * @clks: the clk_bulk_data table being unprepared
+ *
+ * clk_bulk_unprepare may sleep, which differentiates it from clk_bulk_disable.
+ * Returns 0 on success, -EERROR otherwise.
+ */
+void clk_bulk_unprepare(int num_clks, const struct clk_bulk_data *clks)
+{
+ while (--num_clks >= 0)
+ clk_unprepare(clks[num_clks].clk);
+}
+EXPORT_SYMBOL_GPL(clk_bulk_unprepare);
+
+/**
+ * clk_bulk_prepare - prepare a set of clocks
+ * @num_clks: the number of clk_bulk_data
+ * @clks: the clk_bulk_data table being prepared
+ *
+ * clk_bulk_prepare may sleep, which differentiates it from clk_bulk_enable.
+ * Returns 0 on success, -EERROR otherwise.
+ */
+int __must_check clk_bulk_prepare(int num_clks,
+ const struct clk_bulk_data *clks)
+{
+ int ret;
+ int i;
+
+ for (i = 0; i < num_clks; i++) {
+ ret = clk_prepare(clks[i].clk);
+ if (ret) {
+ pr_err("Failed to prepare clk '%s': %d\n",
+ clks[i].id, ret);
+ goto err;
+ }
+ }
+
+ return 0;
+
+err:
+ clk_bulk_unprepare(i, clks);
+
+ return ret;
+}
+
+#endif /* CONFIG_HAVE_CLK_PREPARE */
+
+/**
+ * clk_bulk_disable - gate a set of clocks
+ * @num_clks: the number of clk_bulk_data
+ * @clks: the clk_bulk_data table being gated
+ *
+ * clk_bulk_disable must not sleep, which differentiates it from
+ * clk_bulk_unprepare. clk_bulk_disable must be called before
+ * clk_bulk_unprepare.
+ */
+void clk_bulk_disable(int num_clks, const struct clk_bulk_data *clks)
+{
+
+ while (--num_clks >= 0)
+ clk_disable(clks[num_clks].clk);
+}
+EXPORT_SYMBOL_GPL(clk_bulk_disable);
+
+/**
+ * clk_bulk_enable - ungate a set of clocks
+ * @num_clks: the number of clk_bulk_data
+ * @clks: the clk_bulk_data table being ungated
+ *
+ * clk_bulk_enable must not sleep
+ * Returns 0 on success, -EERROR otherwise.
+ */
+int __must_check clk_bulk_enable(int num_clks, const struct clk_bulk_data *clks)
+{
+ int ret;
+ int i;
+
+ for (i = 0; i < num_clks; i++) {
+ ret = clk_enable(clks[i].clk);
+ if (ret) {
+ pr_err("Failed to enable clk '%s': %d\n",
+ clks[i].id, ret);
+ goto err;
+ }
+ }
+
+ return 0;
+
+err:
+ clk_bulk_disable(i, clks);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(clk_bulk_enable);
diff --git a/include/linux/clk.h b/include/linux/clk.h
index 024cd07870d0..72b0cfce9165 100644
--- a/include/linux/clk.h
+++ b/include/linux/clk.h
@@ -77,6 +77,21 @@ struct clk_notifier_data {
unsigned long new_rate;
};
+/**
+ * struct clk_bulk_data - Data used for bulk clk operations.
+ *
+ * @id: clock consumer ID
+ * @clk: struct clk * to store the associated clock
+ *
+ * The CLK APIs provide a series of clk_bulk_() API calls as
+ * a convenience to consumers which require multiple clks. This
+ * structure is used to manage data for these calls.
+ */
+struct clk_bulk_data {
+ const char *id;
+ struct clk *clk;
+};
+
#ifdef CONFIG_COMMON_CLK
/**
@@ -185,12 +200,20 @@ static inline bool clk_is_match(const struct clk *p, const struct clk *q)
*/
#ifdef CONFIG_HAVE_CLK_PREPARE
int clk_prepare(struct clk *clk);
+int __must_check clk_bulk_prepare(int num_clks,
+ const struct clk_bulk_data *clks);
#else
static inline int clk_prepare(struct clk *clk)
{
might_sleep();
return 0;
}
+
+static inline int clk_bulk_prepare(int num_clks, struct clk_bulk_data *clks)
+{
+ might_sleep();
+ return 0;
+}
#endif
/**
@@ -204,11 +227,16 @@ static inline int clk_prepare(struct clk *clk)
*/
#ifdef CONFIG_HAVE_CLK_PREPARE
void clk_unprepare(struct clk *clk);
+void clk_bulk_unprepare(int num_clks, const struct clk_bulk_data *clks);
#else
static inline void clk_unprepare(struct clk *clk)
{
might_sleep();
}
+static inline void clk_bulk_unprepare(int num_clks, struct clk_bulk_data *clks)
+{
+ might_sleep();
+}
#endif
#ifdef CONFIG_HAVE_CLK
@@ -230,6 +258,29 @@ static inline void clk_unprepare(struct clk *clk)
struct clk *clk_get(struct device *dev, const char *id);
/**
+ * clk_bulk_get - lookup and obtain a number of references to clock producer.
+ * @dev: device for clock "consumer"
+ * @num_clks: the number of clk_bulk_data
+ * @clks: the clk_bulk_data table of consumer
+ *
+ * This helper function allows drivers to get several clk consumers in one
+ * operation. If any of the clk cannot be acquired then any clks
+ * that were obtained will be freed before returning to the caller.
+ *
+ * Returns 0 if all clocks specified in clk_bulk_data table are obtained
+ * successfully, or valid IS_ERR() condition containing errno.
+ * The implementation uses @dev and @clk_bulk_data.id to determine the
+ * clock consumer, and thereby the clock producer.
+ * The clock returned is stored in each @clk_bulk_data.clk field.
+ *
+ * Drivers must assume that the clock source is not enabled.
+ *
+ * clk_bulk_get should not be called from within interrupt context.
+ */
+int __must_check clk_bulk_get(struct device *dev, int num_clks,
+ struct clk_bulk_data *clks);
+
+/**
* devm_clk_get - lookup and obtain a managed reference to a clock producer.
* @dev: device for clock "consumer"
* @id: clock consumer ID
@@ -279,6 +330,18 @@ struct clk *devm_get_clk_from_child(struct device *dev,
int clk_enable(struct clk *clk);
/**
+ * clk_bulk_enable - inform the system when the set of clks should be running.
+ * @num_clks: the number of clk_bulk_data
+ * @clks: the clk_bulk_data table of consumer
+ *
+ * May be called from atomic contexts.
+ *
+ * Returns success (0) or negative errno.
+ */
+int __must_check clk_bulk_enable(int num_clks,
+ const struct clk_bulk_data *clks);
+
+/**
* clk_disable - inform the system when the clock source is no longer required.
* @clk: clock source
*
@@ -295,6 +358,24 @@ int clk_enable(struct clk *clk);
void clk_disable(struct clk *clk);
/**
+ * clk_bulk_disable - inform the system when the set of clks is no
+ * longer required.
+ * @num_clks: the number of clk_bulk_data
+ * @clks: the clk_bulk_data table of consumer
+ *
+ * Inform the system that a set of clks is no longer required by
+ * a driver and may be shut down.
+ *
+ * May be called from atomic contexts.
+ *
+ * Implementation detail: if the set of clks is shared between
+ * multiple drivers, clk_bulk_enable() calls must be balanced by the
+ * same number of clk_bulk_disable() calls for the clock source to be
+ * disabled.
+ */
+void clk_bulk_disable(int num_clks, const struct clk_bulk_data *clks);
+
+/**
* clk_get_rate - obtain the current clock rate (in Hz) for a clock source.
* This is only valid once the clock source has been enabled.
* @clk: clock source
@@ -314,6 +395,19 @@ unsigned long clk_get_rate(struct clk *clk);
void clk_put(struct clk *clk);
/**
+ * clk_bulk_put - "free" the clock source
+ * @num_clks: the number of clk_bulk_data
+ * @clks: the clk_bulk_data table of consumer
+ *
+ * Note: drivers must ensure that all clk_bulk_enable calls made on this
+ * clock source are balanced by clk_bulk_disable calls prior to calling
+ * this function.
+ *
+ * clk_bulk_put should not be called from within interrupt context.
+ */
+void clk_bulk_put(int num_clks, struct clk_bulk_data *clks);
+
+/**
* devm_clk_put - "free" a managed clock source
* @dev: device used to acquire the clock
* @clk: clock source acquired with devm_clk_get()
@@ -445,6 +539,12 @@ static inline struct clk *clk_get(struct device *dev, const char *id)
return NULL;
}
+static inline int clk_bulk_get(struct device *dev, int num_clks,
+ struct clk_bulk_data *clks)
+{
+ return 0;
+}
+
static inline struct clk *devm_clk_get(struct device *dev, const char *id)
{
return NULL;
@@ -458,6 +558,8 @@ static inline struct clk *devm_get_clk_from_child(struct device *dev,
static inline void clk_put(struct clk *clk) {}
+static inline void clk_bulk_put(int num_clks, struct clk_bulk_data *clks) {}
+
static inline void devm_clk_put(struct device *dev, struct clk *clk) {}
static inline int clk_enable(struct clk *clk)
@@ -465,8 +567,17 @@ static inline int clk_enable(struct clk *clk)
return 0;
}
+static inline int clk_bulk_enable(int num_clks, struct clk_bulk_data *clks)
+{
+ return 0;
+}
+
static inline void clk_disable(struct clk *clk) {}
+
+static inline void clk_bulk_disable(int num_clks,
+ struct clk_bulk_data *clks) {}
+
static inline unsigned long clk_get_rate(struct clk *clk)
{
return 0;