linux/drivers/clk/clk-s2mps11.c

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// SPDX-License-Identifier: GPL-2.0+
//
// clk-s2mps11.c - Clock driver for S2MPS11.
//
// Copyright (C) 2013,2014 Samsung Electornics
#include <linux/module.h>
#include <linux/err.h>
#include <linux/of.h>
#include <linux/clkdev.h>
#include <linux/regmap.h>
#include <linux/clk-provider.h>
#include <linux/platform_device.h>
#include <linux/mfd/samsung/s2mps11.h>
#include <linux/mfd/samsung/s2mps13.h>
#include <linux/mfd/samsung/s2mps14.h>
#include <linux/mfd/samsung/s5m8767.h>
#include <linux/mfd/samsung/core.h>
#include <dt-bindings/clock/samsung,s2mps11.h>
struct s2mps11_clk {
struct sec_pmic_dev *iodev;
struct device_node *clk_np;
struct clk_hw hw;
struct clk *clk;
struct clk_lookup *lookup;
u32 mask;
unsigned int reg;
};
static struct s2mps11_clk *to_s2mps11_clk(struct clk_hw *hw)
{
return container_of(hw, struct s2mps11_clk, hw);
}
static int s2mps11_clk_prepare(struct clk_hw *hw)
{
struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);
return regmap_update_bits(s2mps11->iodev->regmap_pmic,
s2mps11->reg,
s2mps11->mask, s2mps11->mask);
}
static void s2mps11_clk_unprepare(struct clk_hw *hw)
{
struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);
regmap_update_bits(s2mps11->iodev->regmap_pmic, s2mps11->reg,
s2mps11->mask, ~s2mps11->mask);
}
static int s2mps11_clk_is_prepared(struct clk_hw *hw)
{
int ret;
u32 val;
struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);
ret = regmap_read(s2mps11->iodev->regmap_pmic,
s2mps11->reg, &val);
if (ret < 0)
return -EINVAL;
return val & s2mps11->mask;
}
static unsigned long s2mps11_clk_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
return 32768;
}
static const struct clk_ops s2mps11_clk_ops = {
.prepare = s2mps11_clk_prepare,
.unprepare = s2mps11_clk_unprepare,
.is_prepared = s2mps11_clk_is_prepared,
.recalc_rate = s2mps11_clk_recalc_rate,
};
/* This s2mps11_clks_init tructure is common to s2mps11, s2mps13 and s2mps14 */
static struct clk_init_data s2mps11_clks_init[S2MPS11_CLKS_NUM] = {
[S2MPS11_CLK_AP] = {
.name = "s2mps11_ap",
.ops = &s2mps11_clk_ops,
},
[S2MPS11_CLK_CP] = {
.name = "s2mps11_cp",
.ops = &s2mps11_clk_ops,
},
[S2MPS11_CLK_BT] = {
.name = "s2mps11_bt",
.ops = &s2mps11_clk_ops,
},
};
static struct device_node *s2mps11_clk_parse_dt(struct platform_device *pdev,
struct clk_init_data *clks_init)
{
struct sec_pmic_dev *iodev = dev_get_drvdata(pdev->dev.parent);
struct device_node *clk_np;
int i;
if (!iodev->dev->of_node)
return ERR_PTR(-EINVAL);
clk_np = of_get_child_by_name(iodev->dev->of_node, "clocks");
if (!clk_np) {
dev_err(&pdev->dev, "could not find clock sub-node\n");
return ERR_PTR(-EINVAL);
}
for (i = 0; i < S2MPS11_CLKS_NUM; i++)
of_property_read_string_index(clk_np, "clock-output-names", i,
&clks_init[i].name);
return clk_np;
}
static int s2mps11_clk_probe(struct platform_device *pdev)
{
struct sec_pmic_dev *iodev = dev_get_drvdata(pdev->dev.parent);
struct s2mps11_clk *s2mps11_clks;
struct clk_hw_onecell_data *clk_data;
unsigned int s2mps11_reg;
int i, ret = 0;
enum sec_device_type hwid = platform_get_device_id(pdev)->driver_data;
s2mps11_clks = devm_kcalloc(&pdev->dev, S2MPS11_CLKS_NUM,
sizeof(*s2mps11_clks), GFP_KERNEL);
if (!s2mps11_clks)
return -ENOMEM;
clk_data = devm_kzalloc(&pdev->dev,
struct_size(clk_data, hws, S2MPS11_CLKS_NUM),
GFP_KERNEL);
if (!clk_data)
return -ENOMEM;
switch (hwid) {
case S2MPS11X:
s2mps11_reg = S2MPS11_REG_RTC_CTRL;
break;
case S2MPS13X:
s2mps11_reg = S2MPS13_REG_RTCCTRL;
break;
case S2MPS14X:
s2mps11_reg = S2MPS14_REG_RTCCTRL;
break;
case S5M8767X:
s2mps11_reg = S5M8767_REG_CTRL1;
break;
default:
dev_err(&pdev->dev, "Invalid device type\n");
return -EINVAL;
}
/* Store clocks of_node in first element of s2mps11_clks array */
s2mps11_clks->clk_np = s2mps11_clk_parse_dt(pdev, s2mps11_clks_init);
if (IS_ERR(s2mps11_clks->clk_np))
return PTR_ERR(s2mps11_clks->clk_np);
for (i = 0; i < S2MPS11_CLKS_NUM; i++) {
if (i == S2MPS11_CLK_CP && hwid == S2MPS14X)
continue; /* Skip clocks not present in some devices */
s2mps11_clks[i].iodev = iodev;
s2mps11_clks[i].hw.init = &s2mps11_clks_init[i];
s2mps11_clks[i].mask = 1 << i;
s2mps11_clks[i].reg = s2mps11_reg;
s2mps11_clks[i].clk = devm_clk_register(&pdev->dev,
&s2mps11_clks[i].hw);
if (IS_ERR(s2mps11_clks[i].clk)) {
dev_err(&pdev->dev, "Fail to register : %s\n",
s2mps11_clks_init[i].name);
ret = PTR_ERR(s2mps11_clks[i].clk);
goto err_reg;
}
s2mps11_clks[i].lookup = clkdev_hw_create(&s2mps11_clks[i].hw,
s2mps11_clks_init[i].name, NULL);
if (!s2mps11_clks[i].lookup) {
ret = -ENOMEM;
goto err_reg;
}
clk_data->hws[i] = &s2mps11_clks[i].hw;
}
clk_data->num = S2MPS11_CLKS_NUM;
of_clk_add_hw_provider(s2mps11_clks->clk_np, of_clk_hw_onecell_get,
clk_data);
platform_set_drvdata(pdev, s2mps11_clks);
return ret;
err_reg:
while (--i >= 0)
clkdev_drop(s2mps11_clks[i].lookup);
return ret;
}
static int s2mps11_clk_remove(struct platform_device *pdev)
{
struct s2mps11_clk *s2mps11_clks = platform_get_drvdata(pdev);
int i;
of_clk_del_provider(s2mps11_clks[0].clk_np);
/* Drop the reference obtained in s2mps11_clk_parse_dt */
of_node_put(s2mps11_clks[0].clk_np);
for (i = 0; i < S2MPS11_CLKS_NUM; i++) {
/* Skip clocks not present on S2MPS14 */
if (!s2mps11_clks[i].lookup)
continue;
clkdev_drop(s2mps11_clks[i].lookup);
}
return 0;
}
static const struct platform_device_id s2mps11_clk_id[] = {
{ "s2mps11-clk", S2MPS11X},
{ "s2mps13-clk", S2MPS13X},
{ "s2mps14-clk", S2MPS14X},
{ "s5m8767-clk", S5M8767X},
{ },
};
MODULE_DEVICE_TABLE(platform, s2mps11_clk_id);
#ifdef CONFIG_OF
/*
* Device is instantiated through parent MFD device and device matching is done
* through platform_device_id.
*
* However if device's DT node contains proper clock compatible and driver is
* built as a module, then the *module* matching will be done trough DT aliases.
* This requires of_device_id table. In the same time this will not change the
* actual *device* matching so do not add .of_match_table.
*/
clk: s2mps11: Add used attribute to s2mps11_dt_match Clang warns after commit 8985167ecf57 ("clk: s2mps11: Fix matching when built as module and DT node contains compatible"): drivers/clk/clk-s2mps11.c:242:34: warning: variable 's2mps11_dt_match' is not needed and will not be emitted [-Wunneeded-internal-declaration] static const struct of_device_id s2mps11_dt_match[] = { ^ 1 warning generated. This warning happens when a variable is used in some construct that doesn't require a reference to that variable to be emitted in the symbol table; in this case, it's MODULE_DEVICE_TABLE, which only needs to hold the data of the variable, not the variable itself. $ nm -S drivers/clk/clk-s2mps11.o | rg s2mps11_dt_match 00000078 000003d4 R __mod_of__s2mps11_dt_match_device_table Normally, with device ID table variables, it means that the variable just needs to be tied to the device declaration at the bottom of the file, like s2mps11_clk_id: $ nm -S drivers/clk/clk-s2mps11.o | rg s2mps11_clk_id 00000000 00000078 R __mod_platform__s2mps11_clk_id_device_table 00000000 00000078 r s2mps11_clk_id However, because the comment above this deliberately doesn't want this variable added to .of_match_table, we need to mark s2mps11_dt_match as __used to silence this warning. This makes it clear to Clang that the variable is used for something, even if a reference to it isn't being emitted. Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Fixes: 8985167ecf57 ("clk: s2mps11: Fix matching when built as module and DT node contains compatible") Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2018-10-19 03:13:40 +08:00
static const struct of_device_id s2mps11_dt_match[] __used = {
{
.compatible = "samsung,s2mps11-clk",
.data = (void *)S2MPS11X,
}, {
.compatible = "samsung,s2mps13-clk",
.data = (void *)S2MPS13X,
}, {
.compatible = "samsung,s2mps14-clk",
.data = (void *)S2MPS14X,
}, {
.compatible = "samsung,s5m8767-clk",
.data = (void *)S5M8767X,
}, {
/* Sentinel */
},
};
MODULE_DEVICE_TABLE(of, s2mps11_dt_match);
#endif
static struct platform_driver s2mps11_clk_driver = {
.driver = {
.name = "s2mps11-clk",
},
.probe = s2mps11_clk_probe,
.remove = s2mps11_clk_remove,
.id_table = s2mps11_clk_id,
};
static int __init s2mps11_clk_init(void)
{
return platform_driver_register(&s2mps11_clk_driver);
}
subsys_initcall(s2mps11_clk_init);
static void __exit s2mps11_clk_cleanup(void)
{
platform_driver_unregister(&s2mps11_clk_driver);
}
module_exit(s2mps11_clk_cleanup);
MODULE_DESCRIPTION("S2MPS11 Clock Driver");
MODULE_AUTHOR("Yadwinder Singh Brar <yadi.brar@samsung.com>");
MODULE_LICENSE("GPL");