clk-busy.c
/*
* Copyright 2012 Freescale Semiconductor, Inc.
* Copyright 2012 Linaro Ltd.
*
* 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.h>
#include <linux/clk-provider.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/jiffies.h>
#include <linux/err.h>
#include "clk.h"
static int clk_busy_wait(void __iomem *reg, u8 shift)
{
unsigned long timeout = jiffies + msecs_to_jiffies(10);
while (readl_relaxed(reg) & (1 << shift))
if (time_after(jiffies, timeout))
return -ETIMEDOUT;
return 0;
}
struct clk_busy_divider {
struct clk_divider div;
const struct clk_ops *div_ops;
void __iomem *reg;
u8 shift;
};
static inline struct clk_busy_divider *to_clk_busy_divider(struct clk_hw *hw)
{
struct clk_divider *div = container_of(hw, struct clk_divider, hw);
return container_of(div, struct clk_busy_divider, div);
}
static unsigned long clk_busy_divider_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct clk_busy_divider *busy = to_clk_busy_divider(hw);
return busy->div_ops->recalc_rate(&busy->div.hw, parent_rate);
}
static long clk_busy_divider_round_rate(struct clk_hw *hw, unsigned long rate,
unsigned long *prate)
{
struct clk_busy_divider *busy = to_clk_busy_divider(hw);
return busy->div_ops->round_rate(&busy->div.hw, rate, prate);
}
static int clk_busy_divider_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
struct clk_busy_divider *busy = to_clk_busy_divider(hw);
int ret;
ret = busy->div_ops->set_rate(&busy->div.hw, rate, parent_rate);
if (!ret)
ret = clk_busy_wait(busy->reg, busy->shift);
return ret;
}
static struct clk_ops clk_busy_divider_ops = {
.recalc_rate = clk_busy_divider_recalc_rate,
.round_rate = clk_busy_divider_round_rate,
.set_rate = clk_busy_divider_set_rate,
};
struct clk *imx_clk_busy_divider(const char *name, const char *parent_name,
void __iomem *reg, u8 shift, u8 width,
void __iomem *busy_reg, u8 busy_shift)
{
struct clk_busy_divider *busy;
struct clk *clk;
struct clk_init_data init;
busy = kzalloc(sizeof(*busy), GFP_KERNEL);
if (!busy)
return ERR_PTR(-ENOMEM);
busy->reg = busy_reg;
busy->shift = busy_shift;
busy->div.reg = reg;
busy->div.shift = shift;
busy->div.width = width;
busy->div.lock = &imx_ccm_lock;
busy->div_ops = &clk_divider_ops;
init.name = name;
init.ops = &clk_busy_divider_ops;
init.flags = CLK_SET_RATE_PARENT;
init.parent_names = &parent_name;
init.num_parents = 1;
busy->div.hw.init = &init;
clk = clk_register(NULL, &busy->div.hw);
if (IS_ERR(clk))
kfree(busy);
return clk;
}
struct clk_busy_mux {
struct clk_mux mux;
const struct clk_ops *mux_ops;
void __iomem *reg;
u8 shift;
};
static inline struct clk_busy_mux *to_clk_busy_mux(struct clk_hw *hw)
{
struct clk_mux *mux = container_of(hw, struct clk_mux, hw);
return container_of(mux, struct clk_busy_mux, mux);
}
static u8 clk_busy_mux_get_parent(struct clk_hw *hw)
{
struct clk_busy_mux *busy = to_clk_busy_mux(hw);
return busy->mux_ops->get_parent(&busy->mux.hw);
}
static int clk_busy_mux_set_parent(struct clk_hw *hw, u8 index)
{
struct clk_busy_mux *busy = to_clk_busy_mux(hw);
int ret;
ret = busy->mux_ops->set_parent(&busy->mux.hw, index);
if (!ret)
ret = clk_busy_wait(busy->reg, busy->shift);
return ret;
}
static struct clk_ops clk_busy_mux_ops = {
.get_parent = clk_busy_mux_get_parent,
.set_parent = clk_busy_mux_set_parent,
};
struct clk *imx_clk_busy_mux(const char *name, void __iomem *reg, u8 shift,
u8 width, void __iomem *busy_reg, u8 busy_shift,
const char **parent_names, int num_parents)
{
struct clk_busy_mux *busy;
struct clk *clk;
struct clk_init_data init;
busy = kzalloc(sizeof(*busy), GFP_KERNEL);
if (!busy)
return ERR_PTR(-ENOMEM);
busy->reg = busy_reg;
busy->shift = busy_shift;
busy->mux.reg = reg;
busy->mux.shift = shift;
busy->mux.mask = BIT(width) - 1;
busy->mux.lock = &imx_ccm_lock;
busy->mux_ops = &clk_mux_ops;
init.name = name;
init.ops = &clk_busy_mux_ops;
init.flags = 0;
init.parent_names = parent_names;
init.num_parents = num_parents;
busy->mux.hw.init = &init;
clk = clk_register(NULL, &busy->mux.hw);
if (IS_ERR(clk))
kfree(busy);
return clk;
}