diff mbox

[v3,1/3] clk: Add regmap support

Message ID 1433864283-25490-2-git-send-email-matthias.bgg@gmail.com (mailing list archive)
State New, archived
Headers show

Commit Message

Matthias Brugger June 9, 2015, 3:38 p.m. UTC
Some devices like SoCs from Mediatek need to use the clock
through a regmap interface.
This patch adds regmap support for the simple multiplexer clock,
the divider clock and the clock gate code.

Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>
---
 drivers/clk/Makefile         |   1 +
 drivers/clk/clk-divider.c    |  71 ++++++++++++++++++++------
 drivers/clk/clk-gate.c       |  60 +++++++++++++++++-----
 drivers/clk/clk-io.c         |  62 +++++++++++++++++++++++
 drivers/clk/clk-io.h         |  13 +++++
 drivers/clk/clk-mux.c        |  94 +++++++++++++++++++++++++++++------
 include/linux/clk-provider.h | 115 +++++++++++++++++++++++++++++++++++++++++--
 7 files changed, 373 insertions(+), 43 deletions(-)
 create mode 100644 drivers/clk/clk-io.c
 create mode 100644 drivers/clk/clk-io.h

Comments

Heiko Stübner June 16, 2015, 9:51 a.m. UTC | #1
Am Dienstag, 9. Juni 2015, 17:38:01 schrieb Matthias Brugger:
> Some devices like SoCs from Mediatek need to use the clock
> through a regmap interface.
> This patch adds regmap support for the simple multiplexer clock,
> the divider clock and the clock gate code.
> 
> Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>

From my Rockchip pov, I'd really like for this to land, as Rockchip SoCs carry 
some of their clock definitions in the "General Register Files", which get 
accessed through a syscon/regmap.

Nevertheless I found some small'ish issues below.


> ---
>  drivers/clk/Makefile         |   1 +
>  drivers/clk/clk-divider.c    |  71 ++++++++++++++++++++------
>  drivers/clk/clk-gate.c       |  60 +++++++++++++++++-----
>  drivers/clk/clk-io.c         |  62 +++++++++++++++++++++++
>  drivers/clk/clk-io.h         |  13 +++++
>  drivers/clk/clk-mux.c        |  94 +++++++++++++++++++++++++++++------
>  include/linux/clk-provider.h | 115
> +++++++++++++++++++++++++++++++++++++++++-- 7 files changed, 373
> insertions(+), 43 deletions(-)
>  create mode 100644 drivers/clk/clk-io.c
>  create mode 100644 drivers/clk/clk-io.h
> 
> diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
> index 3233f0e..63a94f2 100644
> --- a/drivers/clk/Makefile
> +++ b/drivers/clk/Makefile
> @@ -10,6 +10,7 @@ obj-$(CONFIG_COMMON_CLK)	+= clk-mux.o
>  obj-$(CONFIG_COMMON_CLK)	+= clk-composite.o
>  obj-$(CONFIG_COMMON_CLK)	+= clk-fractional-divider.o
>  obj-$(CONFIG_COMMON_CLK)	+= clk-gpio-gate.o
> +obj-$(CONFIG_COMMON_CLK)	+= clk-io.o
>  ifeq ($(CONFIG_OF), y)
>  obj-$(CONFIG_COMMON_CLK)	+= clk-conf.o
>  endif
> diff --git a/drivers/clk/clk-divider.c b/drivers/clk/clk-divider.c
> index 706b578..99f04ea 100644
> --- a/drivers/clk/clk-divider.c
> +++ b/drivers/clk/clk-divider.c
> @@ -18,6 +18,7 @@
>  #include <linux/string.h>
>  #include <linux/log2.h>
> 
> +#include "clk-io.h"

nit: missing blank between #include and comment

>  /*
>   * DOC: basic adjustable divider clock that cannot gate
>   *
> @@ -137,7 +138,8 @@ static unsigned long clk_divider_recalc_rate(struct
> clk_hw *hw, struct clk_divider *divider = to_clk_divider(hw);
>  	unsigned int val;
> 
> -	val = clk_readl(divider->reg) >> divider->shift;
> +	val = clk_io_readl(hw, divider->reg, divider->regmap, divider->offset);
> +	val >>= divider->shift;
>  	val &= div_mask(divider->width);
> 
>  	return divider_recalc_rate(hw, parent_rate, val, divider->table,
> @@ -349,7 +351,10 @@ static long clk_divider_round_rate(struct clk_hw *hw,
> unsigned long rate,
> 
>  	/* if read only, just return current value */
>  	if (divider->flags & CLK_DIVIDER_READ_ONLY) {
> -		bestdiv = readl(divider->reg) >> divider->shift;
> +		bestdiv = clk_io_readl(hw, divider->reg, divider->regmap,
> +				divider->offset);
> +
> +		bestdiv >>= divider->shift;
>  		bestdiv &= div_mask(divider->width);
>  		bestdiv = _get_div(divider->table, bestdiv, divider->flags);
>  		return DIV_ROUND_UP(*prate, bestdiv);
> @@ -392,12 +397,16 @@ static int clk_divider_set_rate(struct clk_hw *hw,
> unsigned long rate,
> 
>  	if (divider->flags & CLK_DIVIDER_HIWORD_MASK) {
>  		val = div_mask(divider->width) << (divider->shift + 16);
> +		val |= value << divider->shift;
> +		clk_io_writel(hw, divider->reg, divider->regmap,
> +			divider->offset, val);
>  	} else {
> -		val = clk_readl(divider->reg);
> -		val &= ~(div_mask(divider->width) << divider->shift);
> +		u32 mask = div_mask(divider->width) << divider->shift;
> +
> +		val = value << divider->shift;
> +		clk_io_update_bits(hw, divider->reg, divider->regmap,
> +			divider->offset, mask, val);
>  	}
> -	val |= value << divider->shift;
> -	clk_writel(val, divider->reg);
> 
>  	if (divider->lock)
>  		spin_unlock_irqrestore(divider->lock, flags);
> @@ -414,9 +423,9 @@ EXPORT_SYMBOL_GPL(clk_divider_ops);
> 
>  static struct 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, const struct clk_div_table *table,
> -		spinlock_t *lock)
> +		void __iomem *reg, struct regmap *regmap, u32 offset,
> +		u8 shift, u8 width, u8 clk_divider_flags,
> +		const struct clk_div_table *table, spinlock_t *lock)
>  {
>  	struct clk_divider *div;
>  	struct clk *clk;
> @@ -441,7 +450,12 @@ static struct clk *_register_divider(struct device
> *dev, const char *name, init.num_parents = (parent_name ? 1 : 0);
> 
>  	/* struct clk_divider assignments */
> -	div->reg = reg;
> +	if (flags & CLK_USE_REGMAP)
> +		div->regmap = regmap;
> +	else
> +		div->reg = reg;
> +
> +	div->offset = offset;
>  	div->shift = shift;
>  	div->width = width;
>  	div->flags = clk_divider_flags;
> @@ -475,8 +489,8 @@ struct clk *clk_register_divider(struct device *dev,
> const char *name, void __iomem *reg, u8 shift, u8 width,
>  		u8 clk_divider_flags, spinlock_t *lock)
>  {
> -	return _register_divider(dev, name, parent_name, flags, reg, shift,
> -			width, clk_divider_flags, NULL, lock);
> +	return _register_divider(dev, name, parent_name, flags, reg, NULL, 0,
> +			shift, width, clk_divider_flags, NULL, lock);
>  }
>  EXPORT_SYMBOL_GPL(clk_register_divider);
> 
> @@ -500,8 +514,8 @@ struct clk *clk_register_divider_table(struct device
> *dev, const char *name, u8 clk_divider_flags, const struct clk_div_table
> *table,
>  		spinlock_t *lock)
>  {
> -	return _register_divider(dev, name, parent_name, flags, reg, shift,
> -			width, clk_divider_flags, table, lock);
> +	return _register_divider(dev, name, parent_name, flags, reg, NULL, 0,
> +			shift, width, clk_divider_flags, table, lock);
>  }
>  EXPORT_SYMBOL_GPL(clk_register_divider_table);
> 
> @@ -520,3 +534,32 @@ void clk_unregister_divider(struct clk *clk)
>  	kfree(div);
>  }
>  EXPORT_SYMBOL_GPL(clk_unregister_divider);
> +
> +#ifdef CONFIG_REGMAP
> +
> +struct clk *clk_regm_register_divider(struct device *dev, const char *name,
> +		const char *parent_name, unsigned long flags,
> +		struct regmap *regmap, u32 offset, u8 shift, u8 width,
> +		u8 clk_divider_flags, spinlock_t *lock)
> +{
> +	flags |= CLK_USE_REGMAP;
> +
> +	return _register_divider(dev, name, parent_name, flags, NULL, regmap,
> +			offset,	shift, width, clk_divider_flags, NULL, lock);
> +}
> +EXPORT_SYMBOL_GPL(clk_regm_register_divider);
> +
> +struct clk *clk_regm_register_divider_table(struct device *dev,
> +		const char *name, const char *parent_name, unsigned long flags,
> +		struct regmap *regmap, u32 offset, u8 shift, u8 width,
> +		u8 clk_divider_flags, const struct clk_div_table *table,
> +		spinlock_t *lock)
> +{
> +	flags |= CLK_USE_REGMAP;
> +
> +	return _register_divider(dev, name, parent_name, flags, NULL, regmap,
> +			offset,	shift, width, clk_divider_flags, table, lock);
> +}
> +EXPORT_SYMBOL_GPL(clk_regm_register_divider_table);
> +
> +#endif
> diff --git a/drivers/clk/clk-gate.c b/drivers/clk/clk-gate.c
> index 551dd06..2a6b696 100644
> --- a/drivers/clk/clk-gate.c
> +++ b/drivers/clk/clk-gate.c
> @@ -16,6 +16,7 @@
>  #include <linux/err.h>
>  #include <linux/string.h>
> 
> +#include "clk-io.h"

same missing blank

>  /**
>   * DOC: basic gatable clock which can gate and ungate it's ouput
>   *
> @@ -46,7 +47,7 @@ static void clk_gate_endisable(struct clk_hw *hw, int
> enable) struct clk_gate *gate = to_clk_gate(hw);
>  	int set = gate->flags & CLK_GATE_SET_TO_DISABLE ? 1 : 0;
>  	unsigned long uninitialized_var(flags);
> -	u32 reg;
> +	u32 reg, mask;
> 
>  	set ^= enable;
> 
> @@ -57,16 +58,21 @@ static void clk_gate_endisable(struct clk_hw *hw, int
> enable) reg = BIT(gate->bit_idx + 16);
>  		if (set)
>  			reg |= BIT(gate->bit_idx);
> +
> +		clk_io_writel(hw, gate->reg, gate->regmap, gate->offset, reg);
>  	} else {
> -		reg = clk_readl(gate->reg);
> +		if (set) {
> +			reg = BIT(gate->bit_idx);
> +			mask = 0x0;
> +		} else {
> +			reg = 0x0;
> +			mask = BIT(gate->bit_idx);
> +		}
> 
> -		if (set)
> -			reg |= BIT(gate->bit_idx);
> -		else
> -			reg &= ~BIT(gate->bit_idx);
> +		clk_io_update_bits(hw, gate->reg, gate->regmap, gate->offset,
> +				mask, reg);
>  	}
> 
> -	clk_writel(reg, gate->reg);
> 
>  	if (gate->lock)
>  		spin_unlock_irqrestore(gate->lock, flags);
> @@ -89,7 +95,7 @@ static int clk_gate_is_enabled(struct clk_hw *hw)
>  	u32 reg;
>  	struct clk_gate *gate = to_clk_gate(hw);
> 
> -	reg = clk_readl(gate->reg);
> +	reg = clk_io_readl(hw, gate->reg, gate->regmap, gate->offset);
> 
>  	/* if a set bit disables this clk, flip it before masking */
>  	if (gate->flags & CLK_GATE_SET_TO_DISABLE)
> @@ -118,10 +124,10 @@ EXPORT_SYMBOL_GPL(clk_gate_ops);
>   * @clk_gate_flags: gate-specific flags for this clock
>   * @lock: shared register lock for this clock
>   */
> -struct clk *clk_register_gate(struct device *dev, const char *name,
> +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)
> +		void __iomem *reg, struct regmap *regmap, u32 offset,
> +		u8 bit_idx, u8 clk_gate_flags, spinlock_t *lock)
>  {
>  	struct clk_gate *gate;
>  	struct clk *clk;
> @@ -146,7 +152,12 @@ struct clk *clk_register_gate(struct device *dev, const
> char *name, init.num_parents = (parent_name ? 1 : 0);
> 
>  	/* struct clk_gate assignments */
> -	gate->reg = reg;
> +	if (flags & CLK_USE_REGMAP)
> +		gate->regmap = regmap;
> +	else
> +		gate->reg = reg;
> +
> +	gate->offset = offset;
>  	gate->bit_idx = bit_idx;
>  	gate->flags = clk_gate_flags;
>  	gate->lock = lock;
> @@ -159,6 +170,15 @@ struct clk *clk_register_gate(struct device *dev, const
> char *name,
> 
>  	return clk;
>  }
> +
> +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)
> +{
> +	return __clk_register_gate(dev, name, parent_name, flags,
> +			reg, NULL, 0, bit_idx, clk_gate_flags, lock);
> +}
>  EXPORT_SYMBOL_GPL(clk_register_gate);
> 
>  void clk_unregister_gate(struct clk *clk)
> @@ -176,3 +196,19 @@ void clk_unregister_gate(struct clk *clk)
>  	kfree(gate);
>  }
>  EXPORT_SYMBOL_GPL(clk_unregister_gate);
> +
> +#ifdef CONFIG_REGMAP
> +
> +struct clk *clk_regm_register_gate(struct device *dev, const char *name,
> +		const char *parent_name, unsigned long flags,
> +		struct regmap *regmap, u32 offset, u8 bit_idx,
> +		u8 clk_gate_flags, spinlock_t *lock)
> +{
> +	flags |= CLK_USE_REGMAP;
> +
> +	return __clk_register_gate(dev, name, parent_name, flags,
> +			NULL, regmap, offset, bit_idx, clk_gate_flags, lock);
> +}
> +EXPORT_SYMBOL_GPL(clk_regm_register_gate);
> +
> +#endif
> diff --git a/drivers/clk/clk-io.c b/drivers/clk/clk-io.c
> new file mode 100644
> index 0000000..14644af
> --- /dev/null
> +++ b/drivers/clk/clk-io.c
> @@ -0,0 +1,62 @@
> +/*
> + * Copyright (C) 2015 Matthias Brugger <matthias.bgg@gmail.com>
> + *
> + * 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.
> + *
> + */
> +
> +#include <linux/clk-provider.h>
> +
> +void clk_io_writel(struct clk_hw *hw, void __iomem *reg, struct regmap
> *regmap, +			u32 offset, u32 val)
> +{
> +	int ret;
> +
> +	if (hw->init && (hw->init->flags & CLK_USE_REGMAP)) {

I'm not sure hw->init is supposed to be accessed during normal operation?

The normal clk code accesses the flags member of struct clk_core, which gets 
filled from hw->init during registration, so might want to do a
	__clk_get_flags(hw->clk) & CLK_USE_REGMAP
instead.


> +		ret = regmap_write(regmap, offset, val);
> +		WARN((ret != 0),
> +			"%s: Error accessing regmap\n",
> +			__clk_get_name(hw->clk));
> +	} else {
> +		clk_writel(val, reg);
> +	}
> +}
> +
> +u32 clk_io_readl(struct clk_hw *hw, void __iomem *reg, struct regmap
> *regmap, +			u32 offset)
> +{
> +	u32 val;
> +	int ret;
> +
> +	if (hw->init && (hw->init->flags & CLK_USE_REGMAP)) {

same as above

> +		ret = regmap_read(regmap, offset, &val);
> +		WARN((ret != 0),
> +			"%s: Error accessing regmap\n",
> +			__clk_get_name(hw->clk));
> +	} else {
> +		val = clk_readl(reg);
> +	}
> +
> +	return val;
> +}
> +
> +void clk_io_update_bits(struct clk_hw *hw, void __iomem *reg,
> +			struct regmap *regmap, u32 offset, u32 mask, u32 val)
> +{
> +	unsigned int tmp;
> +	int ret;
> +
> +	if (hw->init && (hw->init->flags & CLK_USE_REGMAP)) {

same as above

> +		ret = regmap_update_bits(regmap, offset, mask, val);
> +		WARN((ret != 0),
> +			"%s: Error accessing regmap\n",
> +			__clk_get_name(hw->clk));
> +	} else {
> +		tmp = clk_readl(reg);
> +		tmp &= ~mask;
> +		tmp |= val;
> +		clk_writel(tmp, reg);
> +	}
> +}
> diff --git a/drivers/clk/clk-io.h b/drivers/clk/clk-io.h
> new file mode 100644
> index 0000000..8b305fd
> --- /dev/null
> +++ b/drivers/clk/clk-io.h
> @@ -0,0 +1,13 @@
> +#ifndef __LINUX_CLK_IO_H
> +#define __LINUX_CLK_IO_H
> +
> +#include <linux/clk-provider.h>
> +
> +void clk_io_writel(struct clk_hw *hw, void __iomem *reg, struct regmap
> *regmap, +			u32 offset, u32 val);
> +u32 clk_io_readl(struct clk_hw *hw, void __iomem *reg, struct regmap
> *regmap, +			u32 offset);
> +void clk_io_update_bits(struct clk_hw *hw, void __iomem *reg,
> +			struct regmap *regmap, u32 offset, u32 mask, u32 val);
> +
> +#endif
> diff --git a/drivers/clk/clk-mux.c b/drivers/clk/clk-mux.c
> index 6066a01..12fa2d0 100644
> --- a/drivers/clk/clk-mux.c
> +++ b/drivers/clk/clk-mux.c
> @@ -17,6 +17,7 @@
>  #include <linux/io.h>
>  #include <linux/err.h>
> 
> +#include "clk-io.h"

again missing blank

>  /*
>   * DOC: basic adjustable multiplexer clock that cannot gate
>   *
> @@ -42,7 +43,9 @@ static u8 clk_mux_get_parent(struct clk_hw *hw)
>  	 * 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 = clk_readl(mux->reg) >> mux->shift;
> +	val = clk_io_readl(hw, mux->reg, mux->regmap, mux->offset);
> +
> +	val >>= mux->shift;
>  	val &= mux->mask;
> 
>  	if (mux->table) {
> @@ -88,12 +91,15 @@ static int clk_mux_set_parent(struct clk_hw *hw, u8
> index)
> 
>  	if (mux->flags & CLK_MUX_HIWORD_MASK) {
>  		val = mux->mask << (mux->shift + 16);
> +		val |= index << mux->shift;
> +		clk_io_writel(hw, mux->reg, mux->regmap, mux->offset, val);
>  	} else {
> -		val = clk_readl(mux->reg);
> -		val &= ~(mux->mask << mux->shift);
> +		u32 mask = mux->mask << mux->shift;
> +
> +		val = index << mux->shift;
> +		clk_io_update_bits(hw, mux->reg, mux->regmap,
> +				mux->offset, mask, val);
>  	}
> -	val |= index << mux->shift;
> -	clk_writel(val, mux->reg);
> 
>  	if (mux->lock)
>  		spin_unlock_irqrestore(mux->lock, flags);
> @@ -113,10 +119,11 @@ const struct clk_ops clk_mux_ro_ops = {
>  };
>  EXPORT_SYMBOL_GPL(clk_mux_ro_ops);
> 
> -struct clk *clk_register_mux_table(struct device *dev, const char *name,
> +struct clk *__clk_register_mux_table(struct device *dev, const char *name,
>  		const char * const *parent_names, u8 num_parents,
>  		unsigned long flags,
> -		void __iomem *reg, u8 shift, u32 mask,
> +		void __iomem *reg, struct regmap *regmap,
> +		u32 offset, u8 shift, u32 mask,
>  		u8 clk_mux_flags, u32 *table, spinlock_t *lock)
>  {
>  	struct clk_mux *mux;
> @@ -149,7 +156,12 @@ struct clk *clk_register_mux_table(struct device *dev,
> const char *name, init.num_parents = num_parents;
> 
>  	/* struct clk_mux assignments */
> -	mux->reg = reg;
> +	if (flags & CLK_USE_REGMAP)
> +		mux->regmap = regmap;
> +	else
> +		mux->reg = reg;
> +
> +	mux->offset = offset;
>  	mux->shift = shift;
>  	mux->mask = mask;
>  	mux->flags = clk_mux_flags;
> @@ -164,19 +176,40 @@ struct clk *clk_register_mux_table(struct device *dev,
> const char *name,
> 
>  	return clk;
>  }
> +
> +struct clk *clk_register_mux_table(struct device *dev, const char *name,
> +		const char * const *parent_names, u8 num_parents,
> +		unsigned long flags, void __iomem *reg, u8 shift, u32 mask,
> +		u8 clk_mux_flags, u32 *table, spinlock_t *lock)
> +{
> +	return __clk_register_mux_table(dev, name, parent_names, num_parents,
> +						flags, reg, NULL, 0,
> +						shift, mask, clk_mux_flags,
> +						table, lock);
> +}
>  EXPORT_SYMBOL_GPL(clk_register_mux_table);
> 
> -struct clk *clk_register_mux(struct device *dev, const char *name,
> +struct clk *__clk_register_mux(struct device *dev, const char *name,
>  		const char * const *parent_names, u8 num_parents,
> -		unsigned long flags,
> -		void __iomem *reg, u8 shift, u8 width,
> +		unsigned long flags, void __iomem *reg, struct regmap *regmap,
> +		u32 offset, u8 shift, u8 width,
>  		u8 clk_mux_flags, spinlock_t *lock)
>  {
>  	u32 mask = BIT(width) - 1;
> 
> -	return clk_register_mux_table(dev, name, parent_names, num_parents,
> -				      flags, reg, shift, mask, clk_mux_flags,
> -				      NULL, lock);
> +	return __clk_register_mux_table(dev, name, parent_names, num_parents,
> +					flags, reg, regmap, offset, shift, mask,
> +					clk_mux_flags, NULL, lock);
> +}
> +
> +struct clk *clk_register_mux(struct device *dev, const char *name,
> +		const char * const *parent_names, u8 num_parents,
> +		unsigned long flags, void __iomem *reg, u8 shift, u8 width,
> +		u8 clk_mux_flags, spinlock_t *lock)
> +{
> +	return __clk_register_mux(dev, name, parent_names, num_parents, flags,
> +					reg, NULL, 0, shift, width,
> +					clk_mux_flags, lock);
>  }
>  EXPORT_SYMBOL_GPL(clk_register_mux);
> 
> @@ -195,3 +228,36 @@ void clk_unregister_mux(struct clk *clk)
>  	kfree(mux);
>  }
>  EXPORT_SYMBOL_GPL(clk_unregister_mux);
> +
> +#ifdef CONFIG_REGMAP
> +
> +struct clk *clk_regm_register_mux(struct device *dev, const char *name,
> +		const char * const *parent_names, u8 num_parents,
> +		unsigned long flags, struct regmap *regmap,
> +		u32 offset, u8 shift, u8 width,
> +		u8 clk_mux_flags, spinlock_t *lock)
> +{
> +	flags |= CLK_USE_REGMAP;
> +
> +	return __clk_register_mux(dev, name, parent_names, num_parents, flags,
> +					NULL, regmap, offset, shift, width,
> +					clk_mux_flags, lock);
> +}
> +EXPORT_SYMBOL_GPL(clk_regm_register_mux);
> +
> +struct clk *clk_regm_register_mux_table(struct device *dev, const char
> *name, +		const char * const *parent_names, u8 num_parents,
> +		unsigned long flags, struct regmap *regmap,
> +		u32 offset, u8 shift, u32 mask,
> +		u8 clk_mux_flags, u32 *table, spinlock_t *lock)
> +{
> +	flags |= CLK_USE_REGMAP;
> +
> +	return __clk_register_mux_table(dev, name, parent_names, num_parents,
> +					flags, NULL, regmap, offset,
> +					shift, mask, clk_mux_flags,
> +					table, lock);
> +}
> +EXPORT_SYMBOL_GPL(clk_regm_register_mux_table);
> +
> +#endif
> diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h
> index 2e5df06..22acfd5 100644
> --- a/include/linux/clk-provider.h
> +++ b/include/linux/clk-provider.h
> @@ -14,6 +14,7 @@
>  #include <linux/clk.h>
>  #include <linux/io.h>
>  #include <linux/of.h>
> +#include <linux/regmap.h>
> 
>  #ifdef CONFIG_COMMON_CLK
> 
> @@ -31,6 +32,7 @@
>  #define CLK_GET_RATE_NOCACHE	BIT(6) /* do not use the cached clk rate */
>  #define CLK_SET_RATE_NO_REPARENT BIT(7) /* don't re-parent on rate change
> */ #define CLK_GET_ACCURACY_NOCACHE BIT(8) /* do not use the cached clk
> accuracy */ +#define CLK_USE_REGMAP	BIT(9) /* clock uses regmap to access
> its registers */
> 
>  struct clk_hw;
>  struct clk_core;
> @@ -271,6 +273,8 @@ void of_fixed_clk_setup(struct device_node *np);
>   *
>   * @hw:		handle between common and hardware-specific interfaces
>   * @reg:	register controlling gate
> + * @regmap:	regmap used to control the gate
> + * @offset:	offset inside the regmap
>   * @bit_idx:	single bit controlling gate
>   * @flags:	hardware-specific flags
>   * @lock:	register lock
> @@ -288,7 +292,11 @@ void of_fixed_clk_setup(struct device_node *np);
>   */
>  struct clk_gate {
>  	struct clk_hw hw;
> -	void __iomem	*reg;
> +	union {
> +		void __iomem	*reg;
> +		struct regmap	*regmap;
> +	};
> +	u32		offset;
>  	u8		bit_idx;
>  	u8		flags;
>  	spinlock_t	*lock;
> @@ -304,6 +312,25 @@ struct clk *clk_register_gate(struct device *dev, const
> char *name, u8 clk_gate_flags, spinlock_t *lock);
>  void clk_unregister_gate(struct clk *clk);
> 
> +# ifdef CONFIG_REGMAP
> +
> +struct clk *clk_regm_register_gate(struct device *dev, const char *name,
> +		const char *parent_name, unsigned long flags,
> +		struct regmap *regmap, u32 offset, u8 bit_idx,
> +		u8 clk_gate_flags, spinlock_t *lock);
> +
> +#else
> +
> +struct clk *clk_regm_register_gate(struct device *dev, const char *name,
> +		const char *parent_name, unsigned long flags,
> +		struct regmap *regmap, u32 offset, u8 bit_idx,
> +		u8 clk_gate_flags, spinlock_t *lock)
> +{
> +	return NULL;
> +}
> +
> +#endif
> +
>  struct clk_div_table {
>  	unsigned int	val;
>  	unsigned int	div;
> @@ -314,6 +341,8 @@ struct clk_div_table {
>   *
>   * @hw:		handle between common and hardware-specific interfaces
>   * @reg:	register containing the divider
> + * @regmap:	regmap used to access the divider
> + * @offest:	offset inside the regmap
>   * @shift:	shift to the divider bit field
>   * @width:	width of the divider bit field
>   * @table:	array of value/divider pairs, last entry should have div = 0
> @@ -345,7 +374,11 @@ struct clk_div_table {
>   */
>  struct clk_divider {
>  	struct clk_hw	hw;
> -	void __iomem	*reg;
> +	union {
> +		void __iomem	*reg;
> +		struct regmap	*regmap;
> +	};
> +	u32		offset;
>  	u8		shift;
>  	u8		width;
>  	u8		flags;
> @@ -383,11 +416,47 @@ struct clk *clk_register_divider_table(struct device
> *dev, const char *name, spinlock_t *lock);
>  void clk_unregister_divider(struct clk *clk);
> 
> +#ifdef CONFIG_REGMAP
> +
> +struct clk *clk_regm_register_divider(struct device *dev, const char *name,
> +		const char *parent_name, unsigned long flags,
> +		struct regmap *regmap, u32 offset, u8 shift, u8 width,
> +		u8 clk_divider_flags, spinlock_t *lock);
> +
> +struct clk *clk_regm_register_divider_table(struct device *dev,
> +		const char *name, const char *parent_name, unsigned long flags,
> +		struct regmap *regmap, u32 offset, u8 shift, u8 width,
> +		u8 clk_divider_flags, const struct clk_div_table *table,
> +		spinlock_t *lock);
> +
> +#else
> +
> +struct clk *clk_regm_register_divider(struct device *dev, const char *name,
> +		const char *parent_name, unsigned long flags,
> +		struct regmap *regmap, u32 offset, u8 shift, u8 width,
> +		u8 clk_divider_flags, spinlock_t *lock)
> +{
> +	return NULL;
> +}
> +
> +struct clk *clk_regm_register_divider_table(struct device *dev,
> +		const char *name, const char *parent_name, unsigned long flags,
> +		struct regmap *regmap, u32 offset, u8 shift, u8 width,
> +		u8 clk_divider_flags, const struct clk_div_table *table,
> +		spinlock_t *lock)
> +{
> +	return NULL;
> +}

These two either want to be static inline, or could go away completely 
together with the #ifdef CONFIG_REGMAP in the implementations.
Regmap already provides stub functions for everything, and not having all the 
CONFIG_REGMAP ifdefs and multiple stub functions for everything here would 
make the code more readable I guess.


> +
> +#endif
> +
>  /**
>   * struct clk_mux - multiplexer clock
>   *
>   * @hw:		handle between common and hardware-specific interfaces
>   * @reg:	register controlling multiplexer
> + * @regmap:	regmap for controlling multiplexer
> + * @offset:	offset inside the regmap
>   * @shift:	shift to multiplexer bit field
>   * @width:	width of mutliplexer bit field
>   * @flags:	hardware-specific flags
> @@ -408,8 +477,12 @@ void clk_unregister_divider(struct clk *clk);
>   */
>  struct clk_mux {
>  	struct clk_hw	hw;
> -	void __iomem	*reg;
> +	union {
> +		void __iomem	*reg;
> +		struct regmap	*regmap;
> +	};
>  	u32		*table;
> +	u32		offset;
>  	u32		mask;
>  	u8		shift;
>  	u8		flags;
> @@ -439,6 +512,42 @@ struct clk *clk_register_mux_table(struct device *dev,
> const char *name,
> 
>  void clk_unregister_mux(struct clk *clk);
> 
> +#ifdef CONFIG_REGMAP
> +
> +struct clk *clk_regm_register_mux_table(struct device *dev, const char
> *name, +		const char * const *parent_names, u8 num_parents,
> +		unsigned long flags, struct regmap *regmap,
> +		u32 offset, u8 shift, u32 mask,
> +		u8 clk_mux_flags, u32 *table, spinlock_t *lock);
> +
> +struct clk *clk_regm_register_mux(struct device *dev, const char *name,
> +		const char * const *parent_names, u8 num_parents,
> +		unsigned long flags, struct regmap *regmap,
> +		u32 offset, u8 shift, u8 width,
> +		u8 clk_mux_flags, spinlock_t *lock);
> +
> +#else
> +
> +struct clk *clk_regm_register_mux_table(struct device *dev, const char
> *name, +		const char * const *parent_names, u8 num_parents,
> +		unsigned long flags, struct regmap *reg,
> +		u32 offset, u8 shift, u32 mask,
> +		u8 clk_mux_flags, u32 *table, spinlock_t *lock)
> +{
> +	return NULL;
> +}
> +
> +struct clk *clk_regm_register_mux(struct device *dev, const char *name,
> +		const char * const *parent_names, u8 num_parents,
> +		unsigned long flags, struct regmap *reg,
> +		u32 offset, u8 shift, u8 width,
> +		u8 clk_mux_flags, spinlock_t *lock)
> +{
> +	return NULL;
> +}
> +
> +#endif
> +
>  void of_fixed_factor_clk_setup(struct device_node *node);
> 
>  /**
Joachim Eastwood June 16, 2015, 10:23 a.m. UTC | #2
On 9 June 2015 at 17:38, Matthias Brugger <matthias.bgg@gmail.com> wrote:
> Some devices like SoCs from Mediatek need to use the clock
> through a regmap interface.
> This patch adds regmap support for the simple multiplexer clock,
> the divider clock and the clock gate code.
>
> Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>
> ---
>  drivers/clk/Makefile         |   1 +
>  drivers/clk/clk-divider.c    |  71 ++++++++++++++++++++------
>  drivers/clk/clk-gate.c       |  60 +++++++++++++++++-----
>  drivers/clk/clk-io.c         |  62 +++++++++++++++++++++++
>  drivers/clk/clk-io.h         |  13 +++++
>  drivers/clk/clk-mux.c        |  94 +++++++++++++++++++++++++++++------
>  include/linux/clk-provider.h | 115 +++++++++++++++++++++++++++++++++++++++++--
>  7 files changed, 373 insertions(+), 43 deletions(-)
>  create mode 100644 drivers/clk/clk-io.c
>  create mode 100644 drivers/clk/clk-io.h
[...]
> diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h
> index 2e5df06..22acfd5 100644
> --- a/include/linux/clk-provider.h
> +++ b/include/linux/clk-provider.h
> @@ -14,6 +14,7 @@
>  #include <linux/clk.h>
>  #include <linux/io.h>
>  #include <linux/of.h>
> +#include <linux/regmap.h>
>
>  #ifdef CONFIG_COMMON_CLK
>
> @@ -31,6 +32,7 @@
>  #define CLK_GET_RATE_NOCACHE   BIT(6) /* do not use the cached clk rate */
>  #define CLK_SET_RATE_NO_REPARENT BIT(7) /* don't re-parent on rate change */
>  #define CLK_GET_ACCURACY_NOCACHE BIT(8) /* do not use the cached clk accuracy */
> +#define CLK_USE_REGMAP BIT(9) /* clock uses regmap to access its registers */
>
>  struct clk_hw;
>  struct clk_core;
> @@ -271,6 +273,8 @@ void of_fixed_clk_setup(struct device_node *np);
>   *
>   * @hw:                handle between common and hardware-specific interfaces
>   * @reg:       register controlling gate
> + * @regmap:    regmap used to control the gate
> + * @offset:    offset inside the regmap
>   * @bit_idx:   single bit controlling gate
>   * @flags:     hardware-specific flags
>   * @lock:      register lock
> @@ -288,7 +292,11 @@ void of_fixed_clk_setup(struct device_node *np);
>   */
>  struct clk_gate {
>         struct clk_hw hw;
> -       void __iomem    *reg;
> +       union {
> +               void __iomem    *reg;
> +               struct regmap   *regmap;
> +       };
> +       u32             offset;

Maybe using a named union here would be nice here. Something like:
union clk_io {
               void __iomem    *reg;
               struct regmap   *regmap;
};

And you could use this in the clk_gate, clk_mux, and clk_div
structures as well as your clk_io_* functions.
Having both void __iomem *reg and struct regmap *regmap as function
parameters seems a bit awkward to me.

Or maybe even as a structure:
struct clk_io {
               union {
                              void __iomem    *reg;
                              struct regmap   *regmap;
               };
               u32 offset;
}

What do you think?


I would also like to see this land so thanks for doing this work Matthias.
Hope some clk maintainer will have the time to look at it soon also.

regards,
Joachim Eastwood
Matthias Brugger June 16, 2015, 2:13 p.m. UTC | #3
2015-06-16 12:23 GMT+02:00 Joachim  Eastwood <manabian@gmail.com>:
> On 9 June 2015 at 17:38, Matthias Brugger <matthias.bgg@gmail.com> wrote:
>> Some devices like SoCs from Mediatek need to use the clock
>> through a regmap interface.
>> This patch adds regmap support for the simple multiplexer clock,
>> the divider clock and the clock gate code.
>>
>> Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>
>> ---
>>  drivers/clk/Makefile         |   1 +
>>  drivers/clk/clk-divider.c    |  71 ++++++++++++++++++++------
>>  drivers/clk/clk-gate.c       |  60 +++++++++++++++++-----
>>  drivers/clk/clk-io.c         |  62 +++++++++++++++++++++++
>>  drivers/clk/clk-io.h         |  13 +++++
>>  drivers/clk/clk-mux.c        |  94 +++++++++++++++++++++++++++++------
>>  include/linux/clk-provider.h | 115 +++++++++++++++++++++++++++++++++++++++++--
>>  7 files changed, 373 insertions(+), 43 deletions(-)
>>  create mode 100644 drivers/clk/clk-io.c
>>  create mode 100644 drivers/clk/clk-io.h
> [...]
>> diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h
>> index 2e5df06..22acfd5 100644
>> --- a/include/linux/clk-provider.h
>> +++ b/include/linux/clk-provider.h
>> @@ -14,6 +14,7 @@
>>  #include <linux/clk.h>
>>  #include <linux/io.h>
>>  #include <linux/of.h>
>> +#include <linux/regmap.h>
>>
>>  #ifdef CONFIG_COMMON_CLK
>>
>> @@ -31,6 +32,7 @@
>>  #define CLK_GET_RATE_NOCACHE   BIT(6) /* do not use the cached clk rate */
>>  #define CLK_SET_RATE_NO_REPARENT BIT(7) /* don't re-parent on rate change */
>>  #define CLK_GET_ACCURACY_NOCACHE BIT(8) /* do not use the cached clk accuracy */
>> +#define CLK_USE_REGMAP BIT(9) /* clock uses regmap to access its registers */
>>
>>  struct clk_hw;
>>  struct clk_core;
>> @@ -271,6 +273,8 @@ void of_fixed_clk_setup(struct device_node *np);
>>   *
>>   * @hw:                handle between common and hardware-specific interfaces
>>   * @reg:       register controlling gate
>> + * @regmap:    regmap used to control the gate
>> + * @offset:    offset inside the regmap
>>   * @bit_idx:   single bit controlling gate
>>   * @flags:     hardware-specific flags
>>   * @lock:      register lock
>> @@ -288,7 +292,11 @@ void of_fixed_clk_setup(struct device_node *np);
>>   */
>>  struct clk_gate {
>>         struct clk_hw hw;
>> -       void __iomem    *reg;
>> +       union {
>> +               void __iomem    *reg;
>> +               struct regmap   *regmap;
>> +       };
>> +       u32             offset;
>
> Maybe using a named union here would be nice here. Something like:
> union clk_io {
>                void __iomem    *reg;
>                struct regmap   *regmap;
> };
>
> And you could use this in the clk_gate, clk_mux, and clk_div
> structures as well as your clk_io_* functions.
> Having both void __iomem *reg and struct regmap *regmap as function
> parameters seems a bit awkward to me.
>
> Or maybe even as a structure:
> struct clk_io {
>                union {
>                               void __iomem    *reg;
>                               struct regmap   *regmap;
>                };
>                u32 offset;
> }
>
> What do you think?
>

The problem with this approach is, that I would have to change all
clocks which use clk_mux, clk_gate or clk_divider.
Up to now, i tried to find a solution which does not change the
existing interface.
So I would pretty much prefer to hear the opinion from the clk
maintainers first before starting the crusade. :)

Thanks,
Matthias
diff mbox

Patch

diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index 3233f0e..63a94f2 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -10,6 +10,7 @@  obj-$(CONFIG_COMMON_CLK)	+= clk-mux.o
 obj-$(CONFIG_COMMON_CLK)	+= clk-composite.o
 obj-$(CONFIG_COMMON_CLK)	+= clk-fractional-divider.o
 obj-$(CONFIG_COMMON_CLK)	+= clk-gpio-gate.o
+obj-$(CONFIG_COMMON_CLK)	+= clk-io.o
 ifeq ($(CONFIG_OF), y)
 obj-$(CONFIG_COMMON_CLK)	+= clk-conf.o
 endif
diff --git a/drivers/clk/clk-divider.c b/drivers/clk/clk-divider.c
index 706b578..99f04ea 100644
--- a/drivers/clk/clk-divider.c
+++ b/drivers/clk/clk-divider.c
@@ -18,6 +18,7 @@ 
 #include <linux/string.h>
 #include <linux/log2.h>
 
+#include "clk-io.h"
 /*
  * DOC: basic adjustable divider clock that cannot gate
  *
@@ -137,7 +138,8 @@  static unsigned long clk_divider_recalc_rate(struct clk_hw *hw,
 	struct clk_divider *divider = to_clk_divider(hw);
 	unsigned int val;
 
-	val = clk_readl(divider->reg) >> divider->shift;
+	val = clk_io_readl(hw, divider->reg, divider->regmap, divider->offset);
+	val >>= divider->shift;
 	val &= div_mask(divider->width);
 
 	return divider_recalc_rate(hw, parent_rate, val, divider->table,
@@ -349,7 +351,10 @@  static long clk_divider_round_rate(struct clk_hw *hw, unsigned long rate,
 
 	/* if read only, just return current value */
 	if (divider->flags & CLK_DIVIDER_READ_ONLY) {
-		bestdiv = readl(divider->reg) >> divider->shift;
+		bestdiv = clk_io_readl(hw, divider->reg, divider->regmap,
+				divider->offset);
+
+		bestdiv >>= divider->shift;
 		bestdiv &= div_mask(divider->width);
 		bestdiv = _get_div(divider->table, bestdiv, divider->flags);
 		return DIV_ROUND_UP(*prate, bestdiv);
@@ -392,12 +397,16 @@  static int clk_divider_set_rate(struct clk_hw *hw, unsigned long rate,
 
 	if (divider->flags & CLK_DIVIDER_HIWORD_MASK) {
 		val = div_mask(divider->width) << (divider->shift + 16);
+		val |= value << divider->shift;
+		clk_io_writel(hw, divider->reg, divider->regmap,
+			divider->offset, val);
 	} else {
-		val = clk_readl(divider->reg);
-		val &= ~(div_mask(divider->width) << divider->shift);
+		u32 mask = div_mask(divider->width) << divider->shift;
+
+		val = value << divider->shift;
+		clk_io_update_bits(hw, divider->reg, divider->regmap,
+			divider->offset, mask, val);
 	}
-	val |= value << divider->shift;
-	clk_writel(val, divider->reg);
 
 	if (divider->lock)
 		spin_unlock_irqrestore(divider->lock, flags);
@@ -414,9 +423,9 @@  EXPORT_SYMBOL_GPL(clk_divider_ops);
 
 static struct 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, const struct clk_div_table *table,
-		spinlock_t *lock)
+		void __iomem *reg, struct regmap *regmap, u32 offset,
+		u8 shift, u8 width, u8 clk_divider_flags,
+		const struct clk_div_table *table, spinlock_t *lock)
 {
 	struct clk_divider *div;
 	struct clk *clk;
@@ -441,7 +450,12 @@  static struct clk *_register_divider(struct device *dev, const char *name,
 	init.num_parents = (parent_name ? 1 : 0);
 
 	/* struct clk_divider assignments */
-	div->reg = reg;
+	if (flags & CLK_USE_REGMAP)
+		div->regmap = regmap;
+	else
+		div->reg = reg;
+
+	div->offset = offset;
 	div->shift = shift;
 	div->width = width;
 	div->flags = clk_divider_flags;
@@ -475,8 +489,8 @@  struct clk *clk_register_divider(struct device *dev, const char *name,
 		void __iomem *reg, u8 shift, u8 width,
 		u8 clk_divider_flags, spinlock_t *lock)
 {
-	return _register_divider(dev, name, parent_name, flags, reg, shift,
-			width, clk_divider_flags, NULL, lock);
+	return _register_divider(dev, name, parent_name, flags, reg, NULL, 0,
+			shift, width, clk_divider_flags, NULL, lock);
 }
 EXPORT_SYMBOL_GPL(clk_register_divider);
 
@@ -500,8 +514,8 @@  struct clk *clk_register_divider_table(struct device *dev, const char *name,
 		u8 clk_divider_flags, const struct clk_div_table *table,
 		spinlock_t *lock)
 {
-	return _register_divider(dev, name, parent_name, flags, reg, shift,
-			width, clk_divider_flags, table, lock);
+	return _register_divider(dev, name, parent_name, flags, reg, NULL, 0,
+			shift, width, clk_divider_flags, table, lock);
 }
 EXPORT_SYMBOL_GPL(clk_register_divider_table);
 
@@ -520,3 +534,32 @@  void clk_unregister_divider(struct clk *clk)
 	kfree(div);
 }
 EXPORT_SYMBOL_GPL(clk_unregister_divider);
+
+#ifdef CONFIG_REGMAP
+
+struct clk *clk_regm_register_divider(struct device *dev, const char *name,
+		const char *parent_name, unsigned long flags,
+		struct regmap *regmap, u32 offset, u8 shift, u8 width,
+		u8 clk_divider_flags, spinlock_t *lock)
+{
+	flags |= CLK_USE_REGMAP;
+
+	return _register_divider(dev, name, parent_name, flags, NULL, regmap,
+			offset,	shift, width, clk_divider_flags, NULL, lock);
+}
+EXPORT_SYMBOL_GPL(clk_regm_register_divider);
+
+struct clk *clk_regm_register_divider_table(struct device *dev,
+		const char *name, const char *parent_name, unsigned long flags,
+		struct regmap *regmap, u32 offset, u8 shift, u8 width,
+		u8 clk_divider_flags, const struct clk_div_table *table,
+		spinlock_t *lock)
+{
+	flags |= CLK_USE_REGMAP;
+
+	return _register_divider(dev, name, parent_name, flags, NULL, regmap,
+			offset,	shift, width, clk_divider_flags, table, lock);
+}
+EXPORT_SYMBOL_GPL(clk_regm_register_divider_table);
+
+#endif
diff --git a/drivers/clk/clk-gate.c b/drivers/clk/clk-gate.c
index 551dd06..2a6b696 100644
--- a/drivers/clk/clk-gate.c
+++ b/drivers/clk/clk-gate.c
@@ -16,6 +16,7 @@ 
 #include <linux/err.h>
 #include <linux/string.h>
 
+#include "clk-io.h"
 /**
  * DOC: basic gatable clock which can gate and ungate it's ouput
  *
@@ -46,7 +47,7 @@  static void clk_gate_endisable(struct clk_hw *hw, int enable)
 	struct clk_gate *gate = to_clk_gate(hw);
 	int set = gate->flags & CLK_GATE_SET_TO_DISABLE ? 1 : 0;
 	unsigned long uninitialized_var(flags);
-	u32 reg;
+	u32 reg, mask;
 
 	set ^= enable;
 
@@ -57,16 +58,21 @@  static void clk_gate_endisable(struct clk_hw *hw, int enable)
 		reg = BIT(gate->bit_idx + 16);
 		if (set)
 			reg |= BIT(gate->bit_idx);
+
+		clk_io_writel(hw, gate->reg, gate->regmap, gate->offset, reg);
 	} else {
-		reg = clk_readl(gate->reg);
+		if (set) {
+			reg = BIT(gate->bit_idx);
+			mask = 0x0;
+		} else {
+			reg = 0x0;
+			mask = BIT(gate->bit_idx);
+		}
 
-		if (set)
-			reg |= BIT(gate->bit_idx);
-		else
-			reg &= ~BIT(gate->bit_idx);
+		clk_io_update_bits(hw, gate->reg, gate->regmap, gate->offset,
+				mask, reg);
 	}
 
-	clk_writel(reg, gate->reg);
 
 	if (gate->lock)
 		spin_unlock_irqrestore(gate->lock, flags);
@@ -89,7 +95,7 @@  static int clk_gate_is_enabled(struct clk_hw *hw)
 	u32 reg;
 	struct clk_gate *gate = to_clk_gate(hw);
 
-	reg = clk_readl(gate->reg);
+	reg = clk_io_readl(hw, gate->reg, gate->regmap, gate->offset);
 
 	/* if a set bit disables this clk, flip it before masking */
 	if (gate->flags & CLK_GATE_SET_TO_DISABLE)
@@ -118,10 +124,10 @@  EXPORT_SYMBOL_GPL(clk_gate_ops);
  * @clk_gate_flags: gate-specific flags for this clock
  * @lock: shared register lock for this clock
  */
-struct clk *clk_register_gate(struct device *dev, const char *name,
+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)
+		void __iomem *reg, struct regmap *regmap, u32 offset,
+		u8 bit_idx, u8 clk_gate_flags, spinlock_t *lock)
 {
 	struct clk_gate *gate;
 	struct clk *clk;
@@ -146,7 +152,12 @@  struct clk *clk_register_gate(struct device *dev, const char *name,
 	init.num_parents = (parent_name ? 1 : 0);
 
 	/* struct clk_gate assignments */
-	gate->reg = reg;
+	if (flags & CLK_USE_REGMAP)
+		gate->regmap = regmap;
+	else
+		gate->reg = reg;
+
+	gate->offset = offset;
 	gate->bit_idx = bit_idx;
 	gate->flags = clk_gate_flags;
 	gate->lock = lock;
@@ -159,6 +170,15 @@  struct clk *clk_register_gate(struct device *dev, const char *name,
 
 	return clk;
 }
+
+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)
+{
+	return __clk_register_gate(dev, name, parent_name, flags,
+			reg, NULL, 0, bit_idx, clk_gate_flags, lock);
+}
 EXPORT_SYMBOL_GPL(clk_register_gate);
 
 void clk_unregister_gate(struct clk *clk)
@@ -176,3 +196,19 @@  void clk_unregister_gate(struct clk *clk)
 	kfree(gate);
 }
 EXPORT_SYMBOL_GPL(clk_unregister_gate);
+
+#ifdef CONFIG_REGMAP
+
+struct clk *clk_regm_register_gate(struct device *dev, const char *name,
+		const char *parent_name, unsigned long flags,
+		struct regmap *regmap, u32 offset, u8 bit_idx,
+		u8 clk_gate_flags, spinlock_t *lock)
+{
+	flags |= CLK_USE_REGMAP;
+
+	return __clk_register_gate(dev, name, parent_name, flags,
+			NULL, regmap, offset, bit_idx, clk_gate_flags, lock);
+}
+EXPORT_SYMBOL_GPL(clk_regm_register_gate);
+
+#endif
diff --git a/drivers/clk/clk-io.c b/drivers/clk/clk-io.c
new file mode 100644
index 0000000..14644af
--- /dev/null
+++ b/drivers/clk/clk-io.c
@@ -0,0 +1,62 @@ 
+/*
+ * Copyright (C) 2015 Matthias Brugger <matthias.bgg@gmail.com>
+ *
+ * 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.
+ *
+ */
+
+#include <linux/clk-provider.h>
+
+void clk_io_writel(struct clk_hw *hw, void __iomem *reg, struct regmap *regmap,
+			u32 offset, u32 val)
+{
+	int ret;
+
+	if (hw->init && (hw->init->flags & CLK_USE_REGMAP)) {
+		ret = regmap_write(regmap, offset, val);
+		WARN((ret != 0),
+			"%s: Error accessing regmap\n",
+			__clk_get_name(hw->clk));
+	} else {
+		clk_writel(val, reg);
+	}
+}
+
+u32 clk_io_readl(struct clk_hw *hw, void __iomem *reg, struct regmap *regmap,
+			u32 offset)
+{
+	u32 val;
+	int ret;
+
+	if (hw->init && (hw->init->flags & CLK_USE_REGMAP)) {
+		ret = regmap_read(regmap, offset, &val);
+		WARN((ret != 0),
+			"%s: Error accessing regmap\n",
+			__clk_get_name(hw->clk));
+	} else {
+		val = clk_readl(reg);
+	}
+
+	return val;
+}
+
+void clk_io_update_bits(struct clk_hw *hw, void __iomem *reg,
+			struct regmap *regmap, u32 offset, u32 mask, u32 val)
+{
+	unsigned int tmp;
+	int ret;
+
+	if (hw->init && (hw->init->flags & CLK_USE_REGMAP)) {
+		ret = regmap_update_bits(regmap, offset, mask, val);
+		WARN((ret != 0),
+			"%s: Error accessing regmap\n",
+			__clk_get_name(hw->clk));
+	} else {
+		tmp = clk_readl(reg);
+		tmp &= ~mask;
+		tmp |= val;
+		clk_writel(tmp, reg);
+	}
+}
diff --git a/drivers/clk/clk-io.h b/drivers/clk/clk-io.h
new file mode 100644
index 0000000..8b305fd
--- /dev/null
+++ b/drivers/clk/clk-io.h
@@ -0,0 +1,13 @@ 
+#ifndef __LINUX_CLK_IO_H
+#define __LINUX_CLK_IO_H
+
+#include <linux/clk-provider.h>
+
+void clk_io_writel(struct clk_hw *hw, void __iomem *reg, struct regmap *regmap,
+			u32 offset, u32 val);
+u32 clk_io_readl(struct clk_hw *hw, void __iomem *reg, struct regmap *regmap,
+			u32 offset);
+void clk_io_update_bits(struct clk_hw *hw, void __iomem *reg,
+			struct regmap *regmap, u32 offset, u32 mask, u32 val);
+
+#endif
diff --git a/drivers/clk/clk-mux.c b/drivers/clk/clk-mux.c
index 6066a01..12fa2d0 100644
--- a/drivers/clk/clk-mux.c
+++ b/drivers/clk/clk-mux.c
@@ -17,6 +17,7 @@ 
 #include <linux/io.h>
 #include <linux/err.h>
 
+#include "clk-io.h"
 /*
  * DOC: basic adjustable multiplexer clock that cannot gate
  *
@@ -42,7 +43,9 @@  static u8 clk_mux_get_parent(struct clk_hw *hw)
 	 * 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 = clk_readl(mux->reg) >> mux->shift;
+	val = clk_io_readl(hw, mux->reg, mux->regmap, mux->offset);
+
+	val >>= mux->shift;
 	val &= mux->mask;
 
 	if (mux->table) {
@@ -88,12 +91,15 @@  static int clk_mux_set_parent(struct clk_hw *hw, u8 index)
 
 	if (mux->flags & CLK_MUX_HIWORD_MASK) {
 		val = mux->mask << (mux->shift + 16);
+		val |= index << mux->shift;
+		clk_io_writel(hw, mux->reg, mux->regmap, mux->offset, val);
 	} else {
-		val = clk_readl(mux->reg);
-		val &= ~(mux->mask << mux->shift);
+		u32 mask = mux->mask << mux->shift;
+
+		val = index << mux->shift;
+		clk_io_update_bits(hw, mux->reg, mux->regmap,
+				mux->offset, mask, val);
 	}
-	val |= index << mux->shift;
-	clk_writel(val, mux->reg);
 
 	if (mux->lock)
 		spin_unlock_irqrestore(mux->lock, flags);
@@ -113,10 +119,11 @@  const struct clk_ops clk_mux_ro_ops = {
 };
 EXPORT_SYMBOL_GPL(clk_mux_ro_ops);
 
-struct clk *clk_register_mux_table(struct device *dev, const char *name,
+struct clk *__clk_register_mux_table(struct device *dev, const char *name,
 		const char * const *parent_names, u8 num_parents,
 		unsigned long flags,
-		void __iomem *reg, u8 shift, u32 mask,
+		void __iomem *reg, struct regmap *regmap,
+		u32 offset, u8 shift, u32 mask,
 		u8 clk_mux_flags, u32 *table, spinlock_t *lock)
 {
 	struct clk_mux *mux;
@@ -149,7 +156,12 @@  struct clk *clk_register_mux_table(struct device *dev, const char *name,
 	init.num_parents = num_parents;
 
 	/* struct clk_mux assignments */
-	mux->reg = reg;
+	if (flags & CLK_USE_REGMAP)
+		mux->regmap = regmap;
+	else
+		mux->reg = reg;
+
+	mux->offset = offset;
 	mux->shift = shift;
 	mux->mask = mask;
 	mux->flags = clk_mux_flags;
@@ -164,19 +176,40 @@  struct clk *clk_register_mux_table(struct device *dev, const char *name,
 
 	return clk;
 }
+
+struct clk *clk_register_mux_table(struct device *dev, const char *name,
+		const char * const *parent_names, u8 num_parents,
+		unsigned long flags, void __iomem *reg, u8 shift, u32 mask,
+		u8 clk_mux_flags, u32 *table, spinlock_t *lock)
+{
+	return __clk_register_mux_table(dev, name, parent_names, num_parents,
+						flags, reg, NULL, 0,
+						shift, mask, clk_mux_flags,
+						table, lock);
+}
 EXPORT_SYMBOL_GPL(clk_register_mux_table);
 
-struct clk *clk_register_mux(struct device *dev, const char *name,
+struct clk *__clk_register_mux(struct device *dev, const char *name,
 		const char * const *parent_names, u8 num_parents,
-		unsigned long flags,
-		void __iomem *reg, u8 shift, u8 width,
+		unsigned long flags, void __iomem *reg, struct regmap *regmap,
+		u32 offset, u8 shift, u8 width,
 		u8 clk_mux_flags, spinlock_t *lock)
 {
 	u32 mask = BIT(width) - 1;
 
-	return clk_register_mux_table(dev, name, parent_names, num_parents,
-				      flags, reg, shift, mask, clk_mux_flags,
-				      NULL, lock);
+	return __clk_register_mux_table(dev, name, parent_names, num_parents,
+					flags, reg, regmap, offset, shift, mask,
+					clk_mux_flags, NULL, lock);
+}
+
+struct clk *clk_register_mux(struct device *dev, const char *name,
+		const char * const *parent_names, u8 num_parents,
+		unsigned long flags, void __iomem *reg, u8 shift, u8 width,
+		u8 clk_mux_flags, spinlock_t *lock)
+{
+	return __clk_register_mux(dev, name, parent_names, num_parents, flags,
+					reg, NULL, 0, shift, width,
+					clk_mux_flags, lock);
 }
 EXPORT_SYMBOL_GPL(clk_register_mux);
 
@@ -195,3 +228,36 @@  void clk_unregister_mux(struct clk *clk)
 	kfree(mux);
 }
 EXPORT_SYMBOL_GPL(clk_unregister_mux);
+
+#ifdef CONFIG_REGMAP
+
+struct clk *clk_regm_register_mux(struct device *dev, const char *name,
+		const char * const *parent_names, u8 num_parents,
+		unsigned long flags, struct regmap *regmap,
+		u32 offset, u8 shift, u8 width,
+		u8 clk_mux_flags, spinlock_t *lock)
+{
+	flags |= CLK_USE_REGMAP;
+
+	return __clk_register_mux(dev, name, parent_names, num_parents, flags,
+					NULL, regmap, offset, shift, width,
+					clk_mux_flags, lock);
+}
+EXPORT_SYMBOL_GPL(clk_regm_register_mux);
+
+struct clk *clk_regm_register_mux_table(struct device *dev, const char *name,
+		const char * const *parent_names, u8 num_parents,
+		unsigned long flags, struct regmap *regmap,
+		u32 offset, u8 shift, u32 mask,
+		u8 clk_mux_flags, u32 *table, spinlock_t *lock)
+{
+	flags |= CLK_USE_REGMAP;
+
+	return __clk_register_mux_table(dev, name, parent_names, num_parents,
+					flags, NULL, regmap, offset,
+					shift, mask, clk_mux_flags,
+					table, lock);
+}
+EXPORT_SYMBOL_GPL(clk_regm_register_mux_table);
+
+#endif
diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h
index 2e5df06..22acfd5 100644
--- a/include/linux/clk-provider.h
+++ b/include/linux/clk-provider.h
@@ -14,6 +14,7 @@ 
 #include <linux/clk.h>
 #include <linux/io.h>
 #include <linux/of.h>
+#include <linux/regmap.h>
 
 #ifdef CONFIG_COMMON_CLK
 
@@ -31,6 +32,7 @@ 
 #define CLK_GET_RATE_NOCACHE	BIT(6) /* do not use the cached clk rate */
 #define CLK_SET_RATE_NO_REPARENT BIT(7) /* don't re-parent on rate change */
 #define CLK_GET_ACCURACY_NOCACHE BIT(8) /* do not use the cached clk accuracy */
+#define CLK_USE_REGMAP	BIT(9) /* clock uses regmap to access its registers */
 
 struct clk_hw;
 struct clk_core;
@@ -271,6 +273,8 @@  void of_fixed_clk_setup(struct device_node *np);
  *
  * @hw:		handle between common and hardware-specific interfaces
  * @reg:	register controlling gate
+ * @regmap:	regmap used to control the gate
+ * @offset:	offset inside the regmap
  * @bit_idx:	single bit controlling gate
  * @flags:	hardware-specific flags
  * @lock:	register lock
@@ -288,7 +292,11 @@  void of_fixed_clk_setup(struct device_node *np);
  */
 struct clk_gate {
 	struct clk_hw hw;
-	void __iomem	*reg;
+	union {
+		void __iomem	*reg;
+		struct regmap	*regmap;
+	};
+	u32		offset;
 	u8		bit_idx;
 	u8		flags;
 	spinlock_t	*lock;
@@ -304,6 +312,25 @@  struct clk *clk_register_gate(struct device *dev, const char *name,
 		u8 clk_gate_flags, spinlock_t *lock);
 void clk_unregister_gate(struct clk *clk);
 
+# ifdef CONFIG_REGMAP
+
+struct clk *clk_regm_register_gate(struct device *dev, const char *name,
+		const char *parent_name, unsigned long flags,
+		struct regmap *regmap, u32 offset, u8 bit_idx,
+		u8 clk_gate_flags, spinlock_t *lock);
+
+#else
+
+struct clk *clk_regm_register_gate(struct device *dev, const char *name,
+		const char *parent_name, unsigned long flags,
+		struct regmap *regmap, u32 offset, u8 bit_idx,
+		u8 clk_gate_flags, spinlock_t *lock)
+{
+	return NULL;
+}
+
+#endif
+
 struct clk_div_table {
 	unsigned int	val;
 	unsigned int	div;
@@ -314,6 +341,8 @@  struct clk_div_table {
  *
  * @hw:		handle between common and hardware-specific interfaces
  * @reg:	register containing the divider
+ * @regmap:	regmap used to access the divider
+ * @offest:	offset inside the regmap
  * @shift:	shift to the divider bit field
  * @width:	width of the divider bit field
  * @table:	array of value/divider pairs, last entry should have div = 0
@@ -345,7 +374,11 @@  struct clk_div_table {
  */
 struct clk_divider {
 	struct clk_hw	hw;
-	void __iomem	*reg;
+	union {
+		void __iomem	*reg;
+		struct regmap	*regmap;
+	};
+	u32		offset;
 	u8		shift;
 	u8		width;
 	u8		flags;
@@ -383,11 +416,47 @@  struct clk *clk_register_divider_table(struct device *dev, const char *name,
 		spinlock_t *lock);
 void clk_unregister_divider(struct clk *clk);
 
+#ifdef CONFIG_REGMAP
+
+struct clk *clk_regm_register_divider(struct device *dev, const char *name,
+		const char *parent_name, unsigned long flags,
+		struct regmap *regmap, u32 offset, u8 shift, u8 width,
+		u8 clk_divider_flags, spinlock_t *lock);
+
+struct clk *clk_regm_register_divider_table(struct device *dev,
+		const char *name, const char *parent_name, unsigned long flags,
+		struct regmap *regmap, u32 offset, u8 shift, u8 width,
+		u8 clk_divider_flags, const struct clk_div_table *table,
+		spinlock_t *lock);
+
+#else
+
+struct clk *clk_regm_register_divider(struct device *dev, const char *name,
+		const char *parent_name, unsigned long flags,
+		struct regmap *regmap, u32 offset, u8 shift, u8 width,
+		u8 clk_divider_flags, spinlock_t *lock)
+{
+	return NULL;
+}
+
+struct clk *clk_regm_register_divider_table(struct device *dev,
+		const char *name, const char *parent_name, unsigned long flags,
+		struct regmap *regmap, u32 offset, u8 shift, u8 width,
+		u8 clk_divider_flags, const struct clk_div_table *table,
+		spinlock_t *lock)
+{
+	return NULL;
+}
+
+#endif
+
 /**
  * struct clk_mux - multiplexer clock
  *
  * @hw:		handle between common and hardware-specific interfaces
  * @reg:	register controlling multiplexer
+ * @regmap:	regmap for controlling multiplexer
+ * @offset:	offset inside the regmap
  * @shift:	shift to multiplexer bit field
  * @width:	width of mutliplexer bit field
  * @flags:	hardware-specific flags
@@ -408,8 +477,12 @@  void clk_unregister_divider(struct clk *clk);
  */
 struct clk_mux {
 	struct clk_hw	hw;
-	void __iomem	*reg;
+	union {
+		void __iomem	*reg;
+		struct regmap	*regmap;
+	};
 	u32		*table;
+	u32		offset;
 	u32		mask;
 	u8		shift;
 	u8		flags;
@@ -439,6 +512,42 @@  struct clk *clk_register_mux_table(struct device *dev, const char *name,
 
 void clk_unregister_mux(struct clk *clk);
 
+#ifdef CONFIG_REGMAP
+
+struct clk *clk_regm_register_mux_table(struct device *dev, const char *name,
+		const char * const *parent_names, u8 num_parents,
+		unsigned long flags, struct regmap *regmap,
+		u32 offset, u8 shift, u32 mask,
+		u8 clk_mux_flags, u32 *table, spinlock_t *lock);
+
+struct clk *clk_regm_register_mux(struct device *dev, const char *name,
+		const char * const *parent_names, u8 num_parents,
+		unsigned long flags, struct regmap *regmap,
+		u32 offset, u8 shift, u8 width,
+		u8 clk_mux_flags, spinlock_t *lock);
+
+#else
+
+struct clk *clk_regm_register_mux_table(struct device *dev, const char *name,
+		const char * const *parent_names, u8 num_parents,
+		unsigned long flags, struct regmap *reg,
+		u32 offset, u8 shift, u32 mask,
+		u8 clk_mux_flags, u32 *table, spinlock_t *lock)
+{
+	return NULL;
+}
+
+struct clk *clk_regm_register_mux(struct device *dev, const char *name,
+		const char * const *parent_names, u8 num_parents,
+		unsigned long flags, struct regmap *reg,
+		u32 offset, u8 shift, u8 width,
+		u8 clk_mux_flags, spinlock_t *lock)
+{
+	return NULL;
+}
+
+#endif
+
 void of_fixed_factor_clk_setup(struct device_node *node);
 
 /**