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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* clk-gate-shared.c - generic barebox clock support. Based on Linux clk support
*
* Copyright (c) 2017 Sascha Hauer <s.hauer@pengutronix.de>, Pengutronix
*/
#include <common.h>
#include <io.h>
#include <malloc.h>
#include <linux/clk.h>
#include <linux/err.h>
struct clk_gate_shared {
struct clk_hw hw;
const char *parent;
const char *companion_gate;
struct clk *companion_clk;
};
#define to_clk_gate_shared(_hw) container_of(_hw, struct clk_gate_shared, hw)
static struct clk *lookup_companion(struct clk_gate_shared *g)
{
if (IS_ERR(g->companion_clk))
g->companion_clk = clk_lookup(g->companion_gate);
if (IS_ERR(g->companion_clk))
return NULL;
return g->companion_clk;
}
static int clk_gate_shared_enable(struct clk_hw *hw)
{
struct clk_gate_shared *g = to_clk_gate_shared(hw);
return clk_enable(lookup_companion(g));
}
static void clk_gate_shared_disable(struct clk_hw *hw)
{
struct clk_gate_shared *g = to_clk_gate_shared(hw);
clk_disable(lookup_companion(g));
}
static int clk_gate_shared_is_enabled(struct clk_hw *hw)
{
struct clk_gate_shared *g = to_clk_gate_shared(hw);
return clk_is_enabled(lookup_companion(g));
}
static struct clk_ops clk_gate_shared_ops = {
.set_rate = clk_parent_set_rate,
.round_rate = clk_parent_round_rate,
.enable = clk_gate_shared_enable,
.disable = clk_gate_shared_disable,
.is_enabled = clk_gate_shared_is_enabled,
};
static struct clk *clk_gate_shared_alloc(const char *name, const char *parent,
const char *companion, unsigned flags)
{
struct clk_gate_shared *g = xzalloc(sizeof(*g));
g->parent = parent;
g->companion_gate = companion;
g->companion_clk = ERR_PTR(-EINVAL);
g->hw.clk.ops = &clk_gate_shared_ops;
g->hw.clk.name = name;
g->hw.clk.flags = flags;
g->hw.clk.parent_names = &g->parent;
g->hw.clk.num_parents = 1;
return &g->hw.clk;
}
static void clk_gate_shared_free(struct clk *clk)
{
struct clk_hw *hw = clk_to_clk_hw(clk);
struct clk_gate_shared *g = to_clk_gate_shared(hw);
free(g);
}
/*
* clk_gate_shared - register a gate controlled by another gate
* @name: The name of the new clock gate
* @parent: The parent name of the new clock
* companion: The hardware gate this clock is controlled by
* @flags: common CLK_* flags
*
* This gate clock is used when a single software control knob controls multiple
* gates in hardware. The first gate is then registered as the real hardware gate,
* the others are registered with this function. This gate has no hardware control
* itself, but only enables/disabled its companion hardware gate.
*/
struct clk *clk_gate_shared(const char *name, const char *parent, const char *companion,
unsigned flags)
{
struct clk *clk;
int ret;
clk = clk_gate_shared_alloc(name , parent, companion, flags);
ret = bclk_register(clk);
if (ret) {
clk_gate_shared_free(clk);
return ERR_PTR(ret);
}
return clk;
}
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