162 lines
4.1 KiB
C
162 lines
4.1 KiB
C
/*
|
|
* Clock driver for ams AS3722 device.
|
|
*
|
|
* Copyright (c) 2013, NVIDIA Corporation.
|
|
*
|
|
* Author: Laxman Dewangan <ldewangan@nvidia.com>
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License as
|
|
* published by the Free Software Foundation version 2.
|
|
*
|
|
* This program is distributed "as is" WITHOUT ANY WARRANTY of any kind,
|
|
* whether express or implied; 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.h>
|
|
#include <linux/clkdev.h>
|
|
#include <linux/clk-provider.h>
|
|
#include <linux/mfd/as3722.h>
|
|
#include <linux/module.h>
|
|
#include <linux/of.h>
|
|
#include <linux/of_device.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/slab.h>
|
|
|
|
struct as3722_clks {
|
|
struct device *dev;
|
|
struct as3722 *as3722;
|
|
struct clk_hw hw;
|
|
struct clk *clk;
|
|
struct clk_onecell_data clk_data;
|
|
};
|
|
|
|
static inline struct as3722_clks *to_as3722_clks(struct clk_hw *hw)
|
|
{
|
|
return container_of(hw, struct as3722_clks, hw);
|
|
}
|
|
|
|
static unsigned long as3722_clks_recalc_rate(struct clk_hw *hw,
|
|
unsigned long parent_rate)
|
|
{
|
|
return 32768;
|
|
}
|
|
|
|
static int as3722_clks_prepare(struct clk_hw *hw)
|
|
{
|
|
struct as3722_clks *as3722_clks = to_as3722_clks(hw);
|
|
int ret;
|
|
|
|
ret = as3722_update_bits(as3722_clks->as3722, AS3722_RTC_CONTROL_REG,
|
|
AS3722_RTC_CLK32K_OUT_EN, AS3722_RTC_CLK32K_OUT_EN);
|
|
if (ret < 0)
|
|
dev_err(as3722_clks->dev, "RTC_CONTROL_REG update failed, %d\n",
|
|
ret);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static void as3722_clks_unprepare(struct clk_hw *hw)
|
|
{
|
|
struct as3722_clks *as3722_clks = to_as3722_clks(hw);
|
|
int ret;
|
|
|
|
ret = as3722_update_bits(as3722_clks->as3722, AS3722_RTC_CONTROL_REG,
|
|
AS3722_RTC_CLK32K_OUT_EN, 0);
|
|
if (ret < 0)
|
|
dev_err(as3722_clks->dev, "RTC_CONTROL_REG update failed, %d\n",
|
|
ret);
|
|
}
|
|
|
|
static int as3722_clks_is_prepared(struct clk_hw *hw)
|
|
{
|
|
struct as3722_clks *as3722_clks = to_as3722_clks(hw);
|
|
int ret;
|
|
u32 val;
|
|
|
|
ret = as3722_read(as3722_clks->as3722, AS3722_RTC_CONTROL_REG, &val);
|
|
if (ret < 0) {
|
|
dev_err(as3722_clks->dev, "RTC_CONTROL_REG read failed, %d\n",
|
|
ret);
|
|
return ret;
|
|
}
|
|
|
|
return !!(val & AS3722_RTC_CLK32K_OUT_EN);
|
|
}
|
|
|
|
static struct clk_ops as3722_clks_ops = {
|
|
.prepare = as3722_clks_prepare,
|
|
.unprepare = as3722_clks_unprepare,
|
|
.is_prepared = as3722_clks_is_prepared,
|
|
.recalc_rate = as3722_clks_recalc_rate,
|
|
};
|
|
|
|
static struct clk_init_data as3722_clks_hw_init = {
|
|
.name = "clk32k",
|
|
.ops = &as3722_clks_ops,
|
|
.flags = CLK_IS_ROOT | CLK_IGNORE_UNUSED,
|
|
};
|
|
|
|
static int as3722_clks_probe(struct platform_device *pdev)
|
|
{
|
|
struct as3722_clks *as3722_clks;
|
|
struct clk *clk;
|
|
int ret;
|
|
|
|
as3722_clks = devm_kzalloc(&pdev->dev, sizeof(*as3722_clks),
|
|
GFP_KERNEL);
|
|
if (!as3722_clks)
|
|
return -ENOMEM;
|
|
|
|
as3722_clks->clk_data.clks = devm_kzalloc(&pdev->dev,
|
|
sizeof(*as3722_clks->clk_data.clks), GFP_KERNEL);
|
|
if (!as3722_clks->clk_data.clks)
|
|
return -ENOMEM;
|
|
|
|
platform_set_drvdata(pdev, as3722_clks);
|
|
|
|
as3722_clks->as3722 = dev_get_drvdata(pdev->dev.parent);
|
|
as3722_clks->dev = &pdev->dev;
|
|
as3722_clks->hw.init = &as3722_clks_hw_init;
|
|
|
|
clk = devm_clk_register(&pdev->dev, &as3722_clks->hw);
|
|
if (IS_ERR(clk)) {
|
|
ret = PTR_ERR(clk);
|
|
dev_err(&pdev->dev, "Fail to register clock %s, %d\n",
|
|
as3722_clks_hw_init.name, ret);
|
|
return ret;
|
|
}
|
|
as3722_clks->clk = clk;
|
|
as3722_clks->clk_data.clks[0] = clk;
|
|
as3722_clks->clk_data.clk_num = 1;
|
|
ret = of_clk_add_provider(pdev->dev.parent->of_node,
|
|
of_clk_src_simple_get, &as3722_clks->clk_data);
|
|
if (ret < 0)
|
|
dev_err(&pdev->dev, "Fail to add clock driver, %d\n", ret);
|
|
return ret;
|
|
}
|
|
|
|
static int as3722_clks_remove(struct platform_device *pdev)
|
|
{
|
|
of_clk_del_provider(pdev->dev.parent->of_node);
|
|
return 0;
|
|
}
|
|
|
|
static struct platform_driver as3722_clks_driver = {
|
|
.driver = {
|
|
.name = "as3722-clk",
|
|
.owner = THIS_MODULE,
|
|
},
|
|
.probe = as3722_clks_probe,
|
|
.remove = as3722_clks_remove,
|
|
};
|
|
|
|
module_platform_driver(as3722_clks_driver);
|
|
|
|
MODULE_DESCRIPTION("Clock driver for ams AS3722 PMIC Device");
|
|
MODULE_ALIAS("platform:as3722-clk");
|
|
MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
|
|
MODULE_LICENSE("GPL v2");
|