linux/drivers/clk/keystone/syscon-clk.c

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// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2020 Texas Instruments Incorporated - https://www.ti.com/
*/
#include <linux/clk-provider.h>
#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
struct ti_syscon_gate_clk_priv {
struct clk_hw hw;
struct regmap *regmap;
u32 reg;
u32 idx;
};
struct ti_syscon_gate_clk_data {
char *name;
u32 offset;
u32 bit_idx;
};
static struct
ti_syscon_gate_clk_priv *to_ti_syscon_gate_clk_priv(struct clk_hw *hw)
{
return container_of(hw, struct ti_syscon_gate_clk_priv, hw);
}
static int ti_syscon_gate_clk_enable(struct clk_hw *hw)
{
struct ti_syscon_gate_clk_priv *priv = to_ti_syscon_gate_clk_priv(hw);
return regmap_write_bits(priv->regmap, priv->reg, priv->idx,
priv->idx);
}
static void ti_syscon_gate_clk_disable(struct clk_hw *hw)
{
struct ti_syscon_gate_clk_priv *priv = to_ti_syscon_gate_clk_priv(hw);
regmap_write_bits(priv->regmap, priv->reg, priv->idx, 0);
}
static int ti_syscon_gate_clk_is_enabled(struct clk_hw *hw)
{
unsigned int val;
struct ti_syscon_gate_clk_priv *priv = to_ti_syscon_gate_clk_priv(hw);
regmap_read(priv->regmap, priv->reg, &val);
return !!(val & priv->idx);
}
static const struct clk_ops ti_syscon_gate_clk_ops = {
.enable = ti_syscon_gate_clk_enable,
.disable = ti_syscon_gate_clk_disable,
.is_enabled = ti_syscon_gate_clk_is_enabled,
};
static struct clk_hw
*ti_syscon_gate_clk_register(struct device *dev, struct regmap *regmap,
const struct ti_syscon_gate_clk_data *data)
{
struct ti_syscon_gate_clk_priv *priv;
struct clk_init_data init;
int ret;
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return ERR_PTR(-ENOMEM);
init.name = data->name;
init.ops = &ti_syscon_gate_clk_ops;
init.parent_names = NULL;
init.num_parents = 0;
init.flags = 0;
priv->regmap = regmap;
priv->reg = data->offset;
priv->idx = BIT(data->bit_idx);
priv->hw.init = &init;
ret = devm_clk_hw_register(dev, &priv->hw);
if (ret)
return ERR_PTR(ret);
return &priv->hw;
}
static int ti_syscon_gate_clk_probe(struct platform_device *pdev)
{
const struct ti_syscon_gate_clk_data *data, *p;
struct clk_hw_onecell_data *hw_data;
struct device *dev = &pdev->dev;
struct regmap *regmap;
int num_clks, i;
data = device_get_match_data(dev);
if (!data)
return -EINVAL;
regmap = syscon_node_to_regmap(dev->of_node);
if (IS_ERR(regmap)) {
if (PTR_ERR(regmap) == -EPROBE_DEFER)
return -EPROBE_DEFER;
dev_err(dev, "failed to find parent regmap\n");
return PTR_ERR(regmap);
}
num_clks = 0;
for (p = data; p->name; p++)
num_clks++;
hw_data = devm_kzalloc(dev, struct_size(hw_data, hws, num_clks),
GFP_KERNEL);
if (!hw_data)
return -ENOMEM;
hw_data->num = num_clks;
for (i = 0; i < num_clks; i++) {
hw_data->hws[i] = ti_syscon_gate_clk_register(dev, regmap,
&data[i]);
if (IS_ERR(hw_data->hws[i]))
dev_warn(dev, "failed to register %s\n",
data[i].name);
}
return devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get,
hw_data);
}
#define TI_SYSCON_CLK_GATE(_name, _offset, _bit_idx) \
{ \
.name = _name, \
.offset = (_offset), \
.bit_idx = (_bit_idx), \
}
static const struct ti_syscon_gate_clk_data am654_clk_data[] = {
TI_SYSCON_CLK_GATE("ehrpwm_tbclk0", 0x0, 0),
TI_SYSCON_CLK_GATE("ehrpwm_tbclk1", 0x4, 0),
TI_SYSCON_CLK_GATE("ehrpwm_tbclk2", 0x8, 0),
TI_SYSCON_CLK_GATE("ehrpwm_tbclk3", 0xc, 0),
TI_SYSCON_CLK_GATE("ehrpwm_tbclk4", 0x10, 0),
TI_SYSCON_CLK_GATE("ehrpwm_tbclk5", 0x14, 0),
{ /* Sentinel */ },
};
static const struct of_device_id ti_syscon_gate_clk_ids[] = {
{
.compatible = "ti,am654-ehrpwm-tbclk",
.data = &am654_clk_data,
},
{ }
};
MODULE_DEVICE_TABLE(of, ti_syscon_gate_clk_ids);
static struct platform_driver ti_syscon_gate_clk_driver = {
.probe = ti_syscon_gate_clk_probe,
.driver = {
.name = "ti-syscon-gate-clk",
.of_match_table = ti_syscon_gate_clk_ids,
},
};
module_platform_driver(ti_syscon_gate_clk_driver);
MODULE_AUTHOR("Vignesh Raghavendra <vigneshr@ti.com>");
MODULE_DESCRIPTION("Syscon backed gate-clock driver");
MODULE_LICENSE("GPL");