linux-sg2042/drivers/clk/clk-hi655x.c

127 lines
3.2 KiB
C

/*
* Clock driver for Hi655x
*
* Copyright (c) 2017, Linaro Ltd.
*
* Author: Daniel Lezcano <daniel.lezcano@linaro.org>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*/
#include <linux/clk-provider.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/slab.h>
#include <linux/mfd/core.h>
#include <linux/mfd/hi655x-pmic.h>
#define HI655X_CLK_BASE HI655X_BUS_ADDR(0x1c)
#define HI655X_CLK_SET BIT(6)
struct hi655x_clk {
struct hi655x_pmic *hi655x;
struct clk_hw clk_hw;
};
static unsigned long hi655x_clk_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
return 32768;
}
static int hi655x_clk_enable(struct clk_hw *hw, bool enable)
{
struct hi655x_clk *hi655x_clk =
container_of(hw, struct hi655x_clk, clk_hw);
struct hi655x_pmic *hi655x = hi655x_clk->hi655x;
return regmap_update_bits(hi655x->regmap, HI655X_CLK_BASE,
HI655X_CLK_SET, enable ? HI655X_CLK_SET : 0);
}
static int hi655x_clk_prepare(struct clk_hw *hw)
{
return hi655x_clk_enable(hw, true);
}
static void hi655x_clk_unprepare(struct clk_hw *hw)
{
hi655x_clk_enable(hw, false);
}
static int hi655x_clk_is_prepared(struct clk_hw *hw)
{
struct hi655x_clk *hi655x_clk =
container_of(hw, struct hi655x_clk, clk_hw);
struct hi655x_pmic *hi655x = hi655x_clk->hi655x;
int ret;
uint32_t val;
ret = regmap_read(hi655x->regmap, HI655X_CLK_BASE, &val);
if (ret < 0)
return ret;
return val & HI655X_CLK_BASE;
}
static const struct clk_ops hi655x_clk_ops = {
.prepare = hi655x_clk_prepare,
.unprepare = hi655x_clk_unprepare,
.is_prepared = hi655x_clk_is_prepared,
.recalc_rate = hi655x_clk_recalc_rate,
};
static int hi655x_clk_probe(struct platform_device *pdev)
{
struct device *parent = pdev->dev.parent;
struct hi655x_pmic *hi655x = dev_get_drvdata(parent);
struct hi655x_clk *hi655x_clk;
const char *clk_name = "hi655x-clk";
struct clk_init_data init = {
.name = clk_name,
.ops = &hi655x_clk_ops
};
int ret;
hi655x_clk = devm_kzalloc(&pdev->dev, sizeof(*hi655x_clk), GFP_KERNEL);
if (!hi655x_clk)
return -ENOMEM;
of_property_read_string_index(parent->of_node, "clock-output-names",
0, &clk_name);
hi655x_clk->clk_hw.init = &init;
hi655x_clk->hi655x = hi655x;
platform_set_drvdata(pdev, hi655x_clk);
ret = devm_clk_hw_register(&pdev->dev, &hi655x_clk->clk_hw);
if (ret)
return ret;
return of_clk_add_hw_provider(parent->of_node, of_clk_hw_simple_get,
&hi655x_clk->clk_hw);
}
static struct platform_driver hi655x_clk_driver = {
.probe = hi655x_clk_probe,
.driver = {
.name = "hi655x-clk",
},
};
module_platform_driver(hi655x_clk_driver);
MODULE_DESCRIPTION("Clk driver for the hi655x series PMICs");
MODULE_AUTHOR("Daniel Lezcano <daniel.lezcano@linaro.org>");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:hi655x-clk");