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Subject[PATCH v7 3/3] clk: basic clock hardware types
Date
Many platforms support simple gateable clocks, fixed-rate clocks,
adjustable divider clocks and multi-parent multiplexer clocks.

This patch introduces basic clock types for the above-mentioned hardware
which share some common characteristics.

Based on original work by Jeremy Kerr and contribution by Jamie Iles.
Dividers and multiplexor clocks originally contributed by Richard Zhao &
Sascha Hauer.

Signed-off-by: Mike Turquette <mturquette@linaro.org>
Signed-off-by: Mike Turquette <mturquette@ti.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Tested-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Rob Herring <rob.herring@calxeda.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Jeremy Kerr <jeremy.kerr@canonical.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Arnd Bergman <arnd.bergmann@linaro.org>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Shawn Guo <shawn.guo@freescale.com>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Jamie Iles <jamie@jamieiles.com>
Cc: Richard Zhao <richard.zhao@linaro.org>
Cc: Saravana Kannan <skannan@codeaurora.org>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Linus Walleij <linus.walleij@stericsson.com>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Amit Kucheria <amit.kucheria@linaro.org>
Cc: Deepak Saxena <dsaxena@linaro.org>
Cc: Grant Likely <grant.likely@secretlab.ca>
---
Changes since v6:
* fixed up clk_divider's .round_rate logic (thanks Sascha)
* removed useless locking around basic clock types

Changes since v5:
* standardized the hw-specific locking in the basic clock types
* export the individual ops for each basic clock type
* improve registration for single-parent basic clocks (thanks Sascha)
* fixed bugs in gate clock's static initializers (thanks Andrew)

drivers/clk/Makefile | 3 +-
drivers/clk/clk-divider.c | 200 ++++++++++++++++++++++++++++++++++++++++++
drivers/clk/clk-fixed-rate.c | 82 +++++++++++++++++
drivers/clk/clk-gate.c | 150 +++++++++++++++++++++++++++++++
drivers/clk/clk-mux.c | 116 ++++++++++++++++++++++++
include/linux/clk-private.h | 124 ++++++++++++++++++++++++++
include/linux/clk-provider.h | 127 ++++++++++++++++++++++++++
7 files changed, 801 insertions(+), 1 deletions(-)
create mode 100644 drivers/clk/clk-divider.c
create mode 100644 drivers/clk/clk-fixed-rate.c
create mode 100644 drivers/clk/clk-gate.c
create mode 100644 drivers/clk/clk-mux.c

diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index ff362c4..1f736bc 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -1,3 +1,4 @@

obj-$(CONFIG_CLKDEV_LOOKUP) += clkdev.o
-obj-$(CONFIG_COMMON_CLK) += clk.o
+obj-$(CONFIG_COMMON_CLK) += clk.o clk-fixed-rate.o clk-gate.o \
+ clk-mux.o clk-divider.o
diff --git a/drivers/clk/clk-divider.c b/drivers/clk/clk-divider.c
new file mode 100644
index 0000000..d5ac6a7
--- /dev/null
+++ b/drivers/clk/clk-divider.c
@@ -0,0 +1,200 @@
+/*
+ * Copyright (C) 2011 Sascha Hauer, Pengutronix <s.hauer@pengutronix.de>
+ * Copyright (C) 2011 Richard Zhao, Linaro <richard.zhao@linaro.org>
+ * Copyright (C) 2011-2012 Mike Turquette, Linaro Ltd <mturquette@linaro.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Adjustable divider clock implementation
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/err.h>
+#include <linux/string.h>
+
+/*
+ * DOC: basic adjustable divider clock that cannot gate
+ *
+ * Traits of this clock:
+ * prepare - clk_prepare only ensures that parents are prepared
+ * enable - clk_enable only ensures that parents are enabled
+ * rate - rate is adjustable. clk->rate = parent->rate / divisor
+ * parent - fixed parent. No clk_set_parent support
+ */
+
+#define to_clk_divider(_hw) container_of(_hw, struct clk_divider, hw)
+
+#define div_mask(d) ((1 << (d->width)) - 1)
+
+static unsigned long clk_divider_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct clk_divider *divider = to_clk_divider(hw);
+ unsigned int div;
+
+ div = readl(divider->reg) >> divider->shift;
+ div &= div_mask(divider);
+
+ if (!(divider->flags & CLK_DIVIDER_ONE_BASED))
+ div++;
+
+ return parent_rate / div;
+}
+EXPORT_SYMBOL_GPL(clk_divider_recalc_rate);
+
+/*
+ * The reverse of DIV_ROUND_UP: The maximum number which
+ * divided by m is r
+ */
+#define MULT_ROUND_UP(r, m) ((r) * (m) + (m) - 1)
+
+static int clk_divider_bestdiv(struct clk_hw *hw, unsigned long rate,
+ unsigned long *best_parent_rate)
+{
+ struct clk_divider *divider = to_clk_divider(hw);
+ int i, bestdiv = 0;
+ unsigned long parent_rate, best = 0, now, maxdiv;
+
+ if (!rate)
+ rate = 1;
+
+ maxdiv = (1 << divider->width);
+
+ if (divider->flags & CLK_DIVIDER_ONE_BASED)
+ maxdiv--;
+
+ if (!best_parent_rate) {
+ parent_rate = __clk_get_rate(__clk_get_parent(hw->clk));
+ bestdiv = DIV_ROUND_UP(parent_rate, rate);
+ bestdiv = bestdiv == 0 ? 1 : bestdiv;
+ bestdiv = bestdiv > maxdiv ? maxdiv : bestdiv;
+ return bestdiv;
+ }
+
+ /*
+ * The maximum divider we can use without overflowing
+ * unsigned long in rate * i below
+ */
+ maxdiv = min(ULONG_MAX / rate, maxdiv);
+
+ for (i = 1; i <= maxdiv; i++) {
+ parent_rate = __clk_round_rate(__clk_get_parent(hw->clk),
+ MULT_ROUND_UP(rate, i));
+ now = parent_rate / i;
+ if (now <= rate && now > best) {
+ bestdiv = i;
+ best = now;
+ *best_parent_rate = parent_rate;
+ }
+ }
+
+ if (!bestdiv) {
+ bestdiv = (1 << divider->width);
+ if (divider->flags & CLK_DIVIDER_ONE_BASED)
+ bestdiv--;
+ *best_parent_rate = __clk_round_rate(__clk_get_parent(hw->clk), 1);
+ }
+
+ return bestdiv;
+}
+
+static long clk_divider_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *prate)
+{
+ int div;
+ div = clk_divider_bestdiv(hw, rate, prate);
+
+ if (prate)
+ return *prate / div;
+ else {
+ unsigned long r;
+ r = __clk_get_rate(__clk_get_parent(hw->clk));
+ return r / div;
+ }
+}
+EXPORT_SYMBOL_GPL(clk_divider_round_rate);
+
+static int clk_divider_set_rate(struct clk_hw *hw, unsigned long rate)
+{
+ struct clk_divider *divider = to_clk_divider(hw);
+ unsigned int div;
+ unsigned long flags = 0;
+ u32 val;
+
+ div = __clk_get_rate(__clk_get_parent(hw->clk)) / rate;
+
+ if (!(divider->flags & CLK_DIVIDER_ONE_BASED))
+ div--;
+
+ if (div > div_mask(divider))
+ div = div_mask(divider);
+
+ if (divider->lock)
+ spin_lock_irqsave(divider->lock, flags);
+
+ val = readl(divider->reg);
+ val &= ~(div_mask(divider) << divider->shift);
+ val |= div << divider->shift;
+ writel(val, divider->reg);
+
+ if (divider->lock)
+ spin_unlock_irqrestore(divider->lock, flags);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(clk_divider_set_rate);
+
+struct clk_ops clk_divider_ops = {
+ .recalc_rate = clk_divider_recalc_rate,
+ .round_rate = clk_divider_round_rate,
+ .set_rate = clk_divider_set_rate,
+};
+EXPORT_SYMBOL_GPL(clk_divider_ops);
+
+struct clk *clk_register_divider(struct device *dev, const char *name,
+ const char *parent_name, unsigned long flags,
+ void __iomem *reg, u8 shift, u8 width,
+ u8 clk_divider_flags, spinlock_t *lock)
+{
+ struct clk_divider *div;
+ struct clk *clk;
+
+ div = kzalloc(sizeof(struct clk_divider), GFP_KERNEL);
+
+ if (!div) {
+ pr_err("%s: could not allocate divider clk\n", __func__);
+ return NULL;
+ }
+
+ /* struct clk_divider assignments */
+ div->reg = reg;
+ div->shift = shift;
+ div->width = width;
+ div->flags = clk_divider_flags;
+ div->lock = lock;
+
+ if (parent_name) {
+ div->parent[0] = kstrdup(parent_name, GFP_KERNEL);
+ if (!div->parent[0])
+ goto out;
+ }
+
+ clk = clk_register(dev, name,
+ &clk_divider_ops, &div->hw,
+ div->parent,
+ (parent_name ? 1 : 0),
+ flags);
+ if (clk)
+ return clk;
+
+out:
+ kfree(div->parent[0]);
+ kfree(div);
+
+ return NULL;
+}
diff --git a/drivers/clk/clk-fixed-rate.c b/drivers/clk/clk-fixed-rate.c
new file mode 100644
index 0000000..90c79fb
--- /dev/null
+++ b/drivers/clk/clk-fixed-rate.c
@@ -0,0 +1,82 @@
+/*
+ * Copyright (C) 2010-2011 Canonical Ltd <jeremy.kerr@canonical.com>
+ * Copyright (C) 2011-2012 Mike Turquette, Linaro Ltd <mturquette@linaro.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Fixed rate clock implementation
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/err.h>
+
+/*
+ * DOC: basic fixed-rate clock that cannot gate
+ *
+ * Traits of this clock:
+ * prepare - clk_(un)prepare only ensures parents are prepared
+ * enable - clk_enable only ensures parents are enabled
+ * rate - rate is always a fixed value. No clk_set_rate support
+ * parent - fixed parent. No clk_set_parent support
+ */
+
+#define to_clk_fixed_rate(_hw) container_of(_hw, struct clk_fixed_rate, hw)
+
+static unsigned long clk_fixed_rate_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ return to_clk_fixed_rate(hw)->fixed_rate;
+}
+EXPORT_SYMBOL_GPL(clk_fixed_rate_recalc_rate);
+
+struct clk_ops clk_fixed_rate_ops = {
+ .recalc_rate = clk_fixed_rate_recalc_rate,
+};
+EXPORT_SYMBOL_GPL(clk_fixed_rate_ops);
+
+struct clk *clk_register_fixed_rate(struct device *dev, const char *name,
+ const char *parent_name, unsigned long flags,
+ unsigned long fixed_rate)
+{
+ struct clk_fixed_rate *fixed;
+ char **parent_names = NULL;
+ u8 len;
+
+ fixed = kzalloc(sizeof(struct clk_fixed_rate), GFP_KERNEL);
+
+ if (!fixed) {
+ pr_err("%s: could not allocate fixed clk\n", __func__);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ /* struct clk_fixed_rate assignments */
+ fixed->fixed_rate = fixed_rate;
+
+ if (parent_name) {
+ parent_names = kmalloc(sizeof(char *), GFP_KERNEL);
+
+ if (! parent_names)
+ goto out;
+
+ len = sizeof(char) * strlen(parent_name);
+
+ parent_names[0] = kmalloc(len, GFP_KERNEL);
+
+ if (!parent_names[0])
+ goto out;
+
+ strncpy(parent_names[0], parent_name, len);
+ }
+
+out:
+ return clk_register(dev, name,
+ &clk_fixed_rate_ops, &fixed->hw,
+ parent_names,
+ (parent_name ? 1 : 0),
+ flags);
+}
diff --git a/drivers/clk/clk-gate.c b/drivers/clk/clk-gate.c
new file mode 100644
index 0000000..b5902e2
--- /dev/null
+++ b/drivers/clk/clk-gate.c
@@ -0,0 +1,150 @@
+/*
+ * Copyright (C) 2010-2011 Canonical Ltd <jeremy.kerr@canonical.com>
+ * Copyright (C) 2011-2012 Mike Turquette, Linaro Ltd <mturquette@linaro.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Gated clock implementation
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/err.h>
+#include <linux/string.h>
+
+/**
+ * DOC: basic gatable clock which can gate and ungate it's ouput
+ *
+ * Traits of this clock:
+ * prepare - clk_(un)prepare only ensures parent is (un)prepared
+ * enable - clk_enable and clk_disable are functional & control gating
+ * rate - inherits rate from parent. No clk_set_rate support
+ * parent - fixed parent. No clk_set_parent support
+ */
+
+#define to_clk_gate(_hw) container_of(_hw, struct clk_gate, hw)
+
+static void clk_gate_set_bit(struct clk_gate *gate)
+{
+ u32 reg;
+ unsigned long flags = 0;
+
+ if (gate->lock)
+ spin_lock_irqsave(gate->lock, flags);
+
+ reg = readl(gate->reg);
+ reg |= BIT(gate->bit_idx);
+ writel(reg, gate->reg);
+
+ if (gate->lock)
+ spin_unlock_irqrestore(gate->lock, flags);
+}
+
+static void clk_gate_clear_bit(struct clk_gate *gate)
+{
+ u32 reg;
+ unsigned long flags = 0;
+
+ if (gate->lock)
+ spin_lock_irqsave(gate->lock, flags);
+
+ reg = readl(gate->reg);
+ reg &= ~BIT(gate->bit_idx);
+ writel(reg, gate->reg);
+
+ if (gate->lock)
+ spin_unlock_irqrestore(gate->lock, flags);
+}
+
+static int clk_gate_enable(struct clk_hw *hw)
+{
+ struct clk_gate *gate = to_clk_gate(hw);
+
+ if (gate->flags & CLK_GATE_SET_TO_DISABLE)
+ clk_gate_clear_bit(gate);
+ else
+ clk_gate_set_bit(gate);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(clk_gate_enable);
+
+static void clk_gate_disable(struct clk_hw *hw)
+{
+ struct clk_gate *gate = to_clk_gate(hw);
+
+ if (gate->flags & CLK_GATE_SET_TO_DISABLE)
+ clk_gate_set_bit(gate);
+ else
+ clk_gate_clear_bit(gate);
+}
+EXPORT_SYMBOL_GPL(clk_gate_disable);
+
+static int clk_gate_is_enabled(struct clk_hw *hw)
+{
+ u32 reg;
+ struct clk_gate *gate = to_clk_gate(hw);
+
+ reg = readl(gate->reg);
+
+ /* if a set bit disables this clk, flip it before masking */
+ if (gate->flags & CLK_GATE_SET_TO_DISABLE)
+ reg ^= BIT(gate->bit_idx);
+
+ reg &= BIT(gate->bit_idx);
+
+ return reg ? 1 : 0;
+}
+EXPORT_SYMBOL_GPL(clk_gate_is_enabled);
+
+struct clk_ops clk_gate_ops = {
+ .enable = clk_gate_enable,
+ .disable = clk_gate_disable,
+ .is_enabled = clk_gate_is_enabled,
+};
+EXPORT_SYMBOL_GPL(clk_gate_ops);
+
+struct clk *clk_register_gate(struct device *dev, const char *name,
+ const char *parent_name, unsigned long flags,
+ void __iomem *reg, u8 bit_idx,
+ u8 clk_gate_flags, spinlock_t *lock)
+{
+ struct clk_gate *gate;
+ struct clk *clk;
+
+ gate = kzalloc(sizeof(struct clk_gate), GFP_KERNEL);
+
+ if (!gate) {
+ pr_err("%s: could not allocate gated clk\n", __func__);
+ return NULL;
+ }
+
+ /* struct clk_gate assignments */
+ gate->reg = reg;
+ gate->bit_idx = bit_idx;
+ gate->flags = clk_gate_flags;
+ gate->lock = lock;
+
+ if (parent_name) {
+ gate->parent[0] = kstrdup(parent_name, GFP_KERNEL);
+ if (!gate->parent[0])
+ goto out;
+ }
+
+ clk = clk_register(dev, name,
+ &clk_gate_ops, &gate->hw,
+ gate->parent,
+ (parent_name ? 1 : 0),
+ flags);
+ if (clk)
+ return clk;
+out:
+ kfree(gate->parent[0]);
+ kfree(gate);
+
+ return NULL;
+}
diff --git a/drivers/clk/clk-mux.c b/drivers/clk/clk-mux.c
new file mode 100644
index 0000000..c71ad1f
--- /dev/null
+++ b/drivers/clk/clk-mux.c
@@ -0,0 +1,116 @@
+/*
+ * Copyright (C) 2011 Sascha Hauer, Pengutronix <s.hauer@pengutronix.de>
+ * Copyright (C) 2011 Richard Zhao, Linaro <richard.zhao@linaro.org>
+ * Copyright (C) 2011-2012 Mike Turquette, Linaro Ltd <mturquette@linaro.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Simple multiplexer clock implementation
+ */
+
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/err.h>
+
+/*
+ * DOC: basic adjustable multiplexer clock that cannot gate
+ *
+ * Traits of this clock:
+ * prepare - clk_prepare only ensures that parents are prepared
+ * enable - clk_enable only ensures that parents are enabled
+ * rate - rate is only affected by parent switching. No clk_set_rate support
+ * parent - parent is adjustable through clk_set_parent
+ */
+
+#define to_clk_mux(_hw) container_of(_hw, struct clk_mux, hw)
+
+static u8 clk_mux_get_parent(struct clk_hw *hw)
+{
+ struct clk_mux *mux = to_clk_mux(hw);
+ u32 val;
+
+ /*
+ * FIXME need a mux-specific flag to determine if val is bitwise or numeric
+ * e.g. sys_clkin_ck's clksel field is 3 bits wide, but ranges from 0x1
+ * to 0x7 (index starts at one)
+ * OTOH, pmd_trace_clk_mux_ck uses a separate bit for each clock, so
+ * val = 0x4 really means "bit 2, index starts at bit 0"
+ */
+ val = readl(mux->reg) >> mux->shift;
+ val &= (1 << mux->width) - 1;
+
+ if (val && (mux->flags & CLK_MUX_INDEX_BIT))
+ val = ffs(val) - 1;
+
+ if (val && (mux->flags & CLK_MUX_INDEX_ONE))
+ val--;
+
+ if (val >= __clk_get_num_parents(hw->clk))
+ return -EINVAL;
+
+ return val;
+}
+EXPORT_SYMBOL_GPL(clk_mux_get_parent);
+
+static int clk_mux_set_parent(struct clk_hw *hw, u8 index)
+{
+ struct clk_mux *mux = to_clk_mux(hw);
+ u32 val;
+ unsigned long flags = 0;
+
+ if (mux->flags & CLK_MUX_INDEX_BIT)
+ index = (1 << ffs(index));
+
+ if (mux->flags & CLK_MUX_INDEX_ONE)
+ index++;
+
+ if (mux->lock)
+ spin_lock_irqsave(mux->lock, flags);
+
+ val = readl(mux->reg);
+ val &= ~(((1 << mux->width) - 1) << mux->shift);
+ val |= index << mux->shift;
+ writel(val, mux->reg);
+
+ if (mux->lock)
+ spin_unlock_irqrestore(mux->lock, flags);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(clk_mux_set_parent);
+
+struct clk_ops clk_mux_ops = {
+ .get_parent = clk_mux_get_parent,
+ .set_parent = clk_mux_set_parent,
+};
+EXPORT_SYMBOL_GPL(clk_mux_ops);
+
+struct clk *clk_register_mux(struct device *dev, const char *name,
+ char **parent_names, u8 num_parents, unsigned long flags,
+ void __iomem *reg, u8 shift, u8 width,
+ u8 clk_mux_flags, spinlock_t *lock)
+{
+ struct clk_mux *mux;
+
+ mux = kmalloc(sizeof(struct clk_mux), GFP_KERNEL);
+
+ if (!mux) {
+ pr_err("%s: could not allocate mux clk\n", __func__);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ /* struct clk_mux assignments */
+ mux->reg = reg;
+ mux->shift = shift;
+ mux->width = width;
+ mux->flags = clk_mux_flags;
+ mux->lock = lock;
+
+ return clk_register(dev, name, &clk_mux_ops, &mux->hw,
+ parent_names, num_parents, flags);
+}
diff --git a/include/linux/clk-private.h b/include/linux/clk-private.h
index e2cce6f..5e4312b 100644
--- a/include/linux/clk-private.h
+++ b/include/linux/clk-private.h
@@ -46,6 +46,130 @@ struct clk {
#endif
};

+/*
+ * DOC: Basic clock implementations common to many platforms
+ *
+ * Each basic clock hardware type is comprised of a structure describing the
+ * clock hardware, implementations of the relevant callbacks in struct clk_ops,
+ * unique flags for that hardware type, a registration function and an
+ * alternative macro for static initialization
+ */
+
+extern struct clk_ops clk_fixed_rate_ops;
+
+#define DEFINE_CLK_FIXED_RATE(_name, _flags, _rate, \
+ _fixed_rate_flags) \
+ static struct clk _name; \
+ static char *_name##_parent_names[] = {}; \
+ static struct clk_fixed_rate _name##_hw = { \
+ .hw = { \
+ .clk = &_name, \
+ }, \
+ .fixed_rate = _rate, \
+ .flags = _fixed_rate_flags, \
+ }; \
+ static struct clk _name = { \
+ .name = #_name, \
+ .ops = &clk_fixed_rate_ops, \
+ .hw = &_name##_hw.hw, \
+ .parent_names = _name##_parent_names, \
+ .num_parents = \
+ ARRAY_SIZE(_name##_parent_names), \
+ .flags = _flags, \
+ };
+
+extern struct clk_ops clk_gate_ops;
+
+#define DEFINE_CLK_GATE(_name, _parent_name, _parent_ptr, \
+ _flags, _reg, _bit_idx, \
+ _gate_flags, _lock) \
+ static struct clk _name; \
+ static char *_name##_parent_names[] = { \
+ _parent_name, \
+ }; \
+ static struct clk *_name##_parents[] = { \
+ _parent_ptr, \
+ }; \
+ static struct clk_gate _name##_hw = { \
+ .hw = { \
+ .clk = &_name, \
+ }, \
+ .reg = _reg, \
+ .bit_idx = _bit_idx, \
+ .flags = _gate_flags, \
+ .lock = _lock, \
+ }; \
+ static struct clk _name = { \
+ .name = #_name, \
+ .ops = &clk_gate_ops, \
+ .hw = &_name##_hw.hw, \
+ .parent_names = _name##_parent_names, \
+ .num_parents = \
+ ARRAY_SIZE(_name##_parent_names), \
+ .parents = _name##_parents, \
+ .flags = _flags, \
+ };
+
+extern struct clk_ops clk_divider_ops;
+
+#define DEFINE_CLK_DIVIDER(_name, _parent_name, _parent_ptr, \
+ _flags, _reg, _shift, _width, \
+ _divider_flags, _lock) \
+ static struct clk _name; \
+ static char *_name##_parent_names[] = { \
+ _parent_name, \
+ }; \
+ static struct clk *_name##_parents[] = { \
+ _parent_ptr, \
+ }; \
+ static struct clk_divider _name##_hw = { \
+ .hw = { \
+ .clk = &_name, \
+ }, \
+ .reg = _reg, \
+ .shift = _shift, \
+ .width = _width, \
+ .flags = _divider_flags, \
+ .lock = _lock, \
+ }; \
+ static struct clk _name = { \
+ .name = #_name, \
+ .ops = &clk_divider_ops, \
+ .hw = &_name##_hw.hw, \
+ .parent_names = _name##_parent_names, \
+ .num_parents = \
+ ARRAY_SIZE(_name##_parent_names), \
+ .parents = _name##_parents, \
+ .flags = _flags, \
+ };
+
+extern struct clk_ops clk_mux_ops;
+
+#define DEFINE_CLK_MUX(_name, _parent_names, _parents, _flags, \
+ _reg, _shift, _width, \
+ _mux_flags, _lock) \
+ static struct clk _name; \
+ static struct clk_mux _name##_hw = { \
+ .hw = { \
+ .clk = &_name, \
+ }, \
+ .reg = _reg, \
+ .shift = _shift, \
+ .width = _width, \
+ .flags = _mux_flags, \
+ .lock = _lock, \
+ }; \
+ static struct clk _name = { \
+ .name = #_name, \
+ .ops = &clk_mux_ops, \
+ .hw = &_name##_hw.hw, \
+ .parent_names = _parent_names, \
+ .num_parents = \
+ ARRAY_SIZE(_parent_names), \
+ .parents = _parents, \
+ .flags = _flags, \
+ };
+
/**
* __clk_init - initialize the data structures in a struct clk
* @dev: device initializing this clk, placeholder for now
diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h
index b18b0e7..5508897 100644
--- a/include/linux/clk-provider.h
+++ b/include/linux/clk-provider.h
@@ -129,6 +129,133 @@ struct clk_ops {
void (*init)(struct clk_hw *hw);
};

+/*
+ * DOC: Basic clock implementations common to many platforms
+ *
+ * Each basic clock hardware type is comprised of a structure describing the
+ * clock hardware, implementations of the relevant callbacks in struct clk_ops,
+ * unique flags for that hardware type, a registration function and an
+ * alternative macro for static initialization
+ */
+
+/**
+ * struct clk_fixed_rate - fixed-rate clock
+ * @hw: handle between common and hardware-specific interfaces
+ * @fixed_rate: constant frequency of clock
+ */
+struct clk_fixed_rate {
+ struct clk_hw hw;
+ unsigned long fixed_rate;
+ u8 flags;
+};
+
+struct clk *clk_register_fixed_rate(struct device *dev, const char *name,
+ const char *parent_name, unsigned long flags,
+ unsigned long fixed_rate);
+
+/**
+ * struct clk_gate - gating clock
+ *
+ * @hw: handle between common and hardware-specific interfaces
+ * @reg: register controlling gate
+ * @bit_idx: single bit controlling gate
+ * @flags: hardware-specific flags
+ * @lock: register lock
+ *
+ * Clock which can gate its output. Implements .enable & .disable
+ *
+ * Flags:
+ * CLK_GATE_SET_DISABLE - by default this clock sets the bit at bit_idx to
+ * enable the clock. Setting this flag does the opposite: setting the bit
+ * disable the clock and clearing it enables the clock
+ */
+struct clk_gate {
+ struct clk_hw hw;
+ void __iomem *reg;
+ u8 bit_idx;
+ u8 flags;
+ spinlock_t *lock;
+ char *parent[1];
+};
+
+#define CLK_GATE_SET_TO_DISABLE BIT(0)
+
+struct clk *clk_register_gate(struct device *dev, const char *name,
+ const char *parent_name, unsigned long flags,
+ void __iomem *reg, u8 bit_idx,
+ u8 clk_gate_flags, spinlock_t *lock);
+
+/**
+ * struct clk_divider - adjustable divider clock
+ *
+ * @hw: handle between common and hardware-specific interfaces
+ * @reg: register containing the divider
+ * @shift: shift to the divider bit field
+ * @width: width of the divider bit field
+ * @lock: register lock
+ *
+ * Clock with an adjustable divider affecting its output frequency. Implements
+ * .recalc_rate, .set_rate and .round_rate
+ *
+ * Flags:
+ * CLK_DIVIDER_ONE_BASED - by default the divisor is the value read from the
+ * register plus one. If CLK_DIVIDER_ONE_BASED is set then the divider is
+ * the raw value read from the register, with the value of zero considered
+ * invalid
+ * CLK_DIVIDER_POWER_OF_TWO - clock divisor is 2 raised to the value read from
+ * the hardware register
+ */
+struct clk_divider {
+ struct clk_hw hw;
+ void __iomem *reg;
+ u8 shift;
+ u8 width;
+ u8 flags;
+ spinlock_t *lock;
+ char *parent[1];
+};
+
+#define CLK_DIVIDER_ONE_BASED BIT(0)
+#define CLK_DIVIDER_POWER_OF_TWO BIT(1)
+
+struct clk *clk_register_divider(struct device *dev, const char *name,
+ const char *parent_name, unsigned long flags,
+ void __iomem *reg, u8 shift, u8 width,
+ u8 clk_divider_flags, spinlock_t *lock);
+
+/**
+ * struct clk_mux - multiplexer clock
+ *
+ * @hw: handle between common and hardware-specific interfaces
+ * @reg: register controlling multiplexer
+ * @shift: shift to multiplexer bit field
+ * @width: width of mutliplexer bit field
+ * @num_clks: number of parent clocks
+ * @lock: register lock
+ *
+ * Clock with multiple selectable parents. Implements .get_parent, .set_parent
+ * and .recalc_rate
+ *
+ * Flags:
+ * CLK_MUX_INDEX_ONE - register index starts at 1, not 0
+ * CLK_MUX_INDEX_BITWISE - register index is a single bit (power of two)
+ */
+struct clk_mux {
+ struct clk_hw hw;
+ void __iomem *reg;
+ u8 shift;
+ u8 width;
+ u8 flags;
+ spinlock_t *lock;
+};
+
+#define CLK_MUX_INDEX_ONE BIT(0)
+#define CLK_MUX_INDEX_BIT BIT(1)
+
+struct clk *clk_register_mux(struct device *dev, const char *name,
+ char **parent_names, u8 num_parents, unsigned long flags,
+ void __iomem *reg, u8 shift, u8 width,
+ u8 clk_mux_flags, spinlock_t *lock);

/**
* clk_register - allocate a new clock, register it and return an opaque cookie
--
1.7.5.4


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