linux/drivers/clk/zynqmp/clk-gate-zynqmp.c

145 lines
3.5 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Zynq UltraScale+ MPSoC clock controller
*
* Copyright (C) 2016-2018 Xilinx
*
* Gated clock implementation
*/
#include <linux/clk-provider.h>
#include <linux/slab.h>
#include "clk-zynqmp.h"
/**
* struct clk_gate - gating clock
* @hw: handle between common and hardware-specific interfaces
* @flags: hardware-specific flags
* @clk_id: Id of clock
*/
struct zynqmp_clk_gate {
struct clk_hw hw;
u8 flags;
u32 clk_id;
};
#define to_zynqmp_clk_gate(_hw) container_of(_hw, struct zynqmp_clk_gate, hw)
/**
* zynqmp_clk_gate_enable() - Enable clock
* @hw: handle between common and hardware-specific interfaces
*
* Return: 0 on success else error code
*/
static int zynqmp_clk_gate_enable(struct clk_hw *hw)
{
struct zynqmp_clk_gate *gate = to_zynqmp_clk_gate(hw);
const char *clk_name = clk_hw_get_name(hw);
u32 clk_id = gate->clk_id;
int ret;
const struct zynqmp_eemi_ops *eemi_ops = zynqmp_pm_get_eemi_ops();
ret = eemi_ops->clock_enable(clk_id);
if (ret)
pr_warn_once("%s() clock enabled failed for %s, ret = %d\n",
__func__, clk_name, ret);
return ret;
}
/*
* zynqmp_clk_gate_disable() - Disable clock
* @hw: handle between common and hardware-specific interfaces
*/
static void zynqmp_clk_gate_disable(struct clk_hw *hw)
{
struct zynqmp_clk_gate *gate = to_zynqmp_clk_gate(hw);
const char *clk_name = clk_hw_get_name(hw);
u32 clk_id = gate->clk_id;
int ret;
const struct zynqmp_eemi_ops *eemi_ops = zynqmp_pm_get_eemi_ops();
ret = eemi_ops->clock_disable(clk_id);
if (ret)
pr_warn_once("%s() clock disable failed for %s, ret = %d\n",
__func__, clk_name, ret);
}
/**
* zynqmp_clk_gate_is_enable() - Check clock state
* @hw: handle between common and hardware-specific interfaces
*
* Return: 1 if enabled, 0 if disabled else error code
*/
static int zynqmp_clk_gate_is_enabled(struct clk_hw *hw)
{
struct zynqmp_clk_gate *gate = to_zynqmp_clk_gate(hw);
const char *clk_name = clk_hw_get_name(hw);
u32 clk_id = gate->clk_id;
int state, ret;
const struct zynqmp_eemi_ops *eemi_ops = zynqmp_pm_get_eemi_ops();
ret = eemi_ops->clock_getstate(clk_id, &state);
if (ret) {
pr_warn_once("%s() clock get state failed for %s, ret = %d\n",
__func__, clk_name, ret);
return -EIO;
}
return state ? 1 : 0;
}
static const struct clk_ops zynqmp_clk_gate_ops = {
.enable = zynqmp_clk_gate_enable,
.disable = zynqmp_clk_gate_disable,
.is_enabled = zynqmp_clk_gate_is_enabled,
};
/**
* zynqmp_clk_register_gate() - Register a gate clock with the clock framework
* @name: Name of this clock
* @clk_id: Id of this clock
* @parents: Name of this clock's parents
* @num_parents: Number of parents
* @nodes: Clock topology node
*
* Return: clock hardware of the registered clock gate
*/
struct clk_hw *zynqmp_clk_register_gate(const char *name, u32 clk_id,
const char * const *parents,
u8 num_parents,
const struct clock_topology *nodes)
{
struct zynqmp_clk_gate *gate;
struct clk_hw *hw;
int ret;
struct clk_init_data init;
/* allocate the gate */
gate = kzalloc(sizeof(*gate), GFP_KERNEL);
if (!gate)
return ERR_PTR(-ENOMEM);
init.name = name;
init.ops = &zynqmp_clk_gate_ops;
init.flags = nodes->flag;
init.parent_names = parents;
init.num_parents = 1;
/* struct clk_gate assignments */
gate->flags = nodes->type_flag;
gate->hw.init = &init;
gate->clk_id = clk_id;
hw = &gate->hw;
ret = clk_hw_register(NULL, hw);
if (ret) {
kfree(gate);
hw = ERR_PTR(ret);
}
return hw;
}