alistair23-linux/drivers/clk/mxs/clk-frac.c
Stephen Boyd bb0bf35452 clk: mxs: Include clk.h in C files that use it
Clock provider drivers generally shouldn't include clk.h because
it's the consumer API. The clk.h include is being included in all
mxs files because it's part of mxs/clk.h even though nothing
actually requires it in that file. Move the clk.h include to the
C files that are actually using it and remove the clk.h include
from the header file. The clkdev.h include isn't used either, so
drop it too.

Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-07-20 11:11:07 -07:00

139 lines
3 KiB
C

/*
* Copyright 2012 Freescale Semiconductor, Inc.
*
* The code contained herein is licensed under the GNU General Public
* License. You may obtain a copy of the GNU General Public License
* Version 2 or later at the following locations:
*
* http://www.opensource.org/licenses/gpl-license.html
* http://www.gnu.org/copyleft/gpl.html
*/
#include <linux/clk-provider.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/slab.h>
#include "clk.h"
/**
* struct clk_frac - mxs fractional divider clock
* @hw: clk_hw for the fractional divider clock
* @reg: register address
* @shift: the divider bit shift
* @width: the divider bit width
* @busy: busy bit shift
*
* The clock is an adjustable fractional divider with a busy bit to wait
* when the divider is adjusted.
*/
struct clk_frac {
struct clk_hw hw;
void __iomem *reg;
u8 shift;
u8 width;
u8 busy;
};
#define to_clk_frac(_hw) container_of(_hw, struct clk_frac, hw)
static unsigned long clk_frac_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct clk_frac *frac = to_clk_frac(hw);
u32 div;
div = readl_relaxed(frac->reg) >> frac->shift;
div &= (1 << frac->width) - 1;
return (parent_rate >> frac->width) * div;
}
static long clk_frac_round_rate(struct clk_hw *hw, unsigned long rate,
unsigned long *prate)
{
struct clk_frac *frac = to_clk_frac(hw);
unsigned long parent_rate = *prate;
u32 div;
u64 tmp;
if (rate > parent_rate)
return -EINVAL;
tmp = rate;
tmp <<= frac->width;
do_div(tmp, parent_rate);
div = tmp;
if (!div)
return -EINVAL;
return (parent_rate >> frac->width) * div;
}
static int clk_frac_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
struct clk_frac *frac = to_clk_frac(hw);
unsigned long flags;
u32 div, val;
u64 tmp;
if (rate > parent_rate)
return -EINVAL;
tmp = rate;
tmp <<= frac->width;
do_div(tmp, parent_rate);
div = tmp;
if (!div)
return -EINVAL;
spin_lock_irqsave(&mxs_lock, flags);
val = readl_relaxed(frac->reg);
val &= ~(((1 << frac->width) - 1) << frac->shift);
val |= div << frac->shift;
writel_relaxed(val, frac->reg);
spin_unlock_irqrestore(&mxs_lock, flags);
return mxs_clk_wait(frac->reg, frac->busy);
}
static struct clk_ops clk_frac_ops = {
.recalc_rate = clk_frac_recalc_rate,
.round_rate = clk_frac_round_rate,
.set_rate = clk_frac_set_rate,
};
struct clk *mxs_clk_frac(const char *name, const char *parent_name,
void __iomem *reg, u8 shift, u8 width, u8 busy)
{
struct clk_frac *frac;
struct clk *clk;
struct clk_init_data init;
frac = kzalloc(sizeof(*frac), GFP_KERNEL);
if (!frac)
return ERR_PTR(-ENOMEM);
init.name = name;
init.ops = &clk_frac_ops;
init.flags = CLK_SET_RATE_PARENT;
init.parent_names = (parent_name ? &parent_name: NULL);
init.num_parents = (parent_name ? 1 : 0);
frac->reg = reg;
frac->shift = shift;
frac->width = width;
frac->busy = busy;
frac->hw.init = &init;
clk = clk_register(NULL, &frac->hw);
if (IS_ERR(clk))
kfree(frac);
return clk;
}