alistair23-linux/drivers/clk/clk-bd718x7.c
Matti Vaittinen 0dae7f5857 clk: bd718x7: Support ROHM BD70528 clk block
ROHM BD70528 is an ultra low power PMIC with similar 32K clk as
bd718x7. Only difference (from clk perspective) is register address.
Add support for controlling BD70528 clk using bd718x7 driver.

Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-06-27 10:57:24 +01:00

136 lines
3.1 KiB
C

// SPDX-License-Identifier: GPL-2.0
// Copyright (C) 2018 ROHM Semiconductors
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/mfd/rohm-bd718x7.h>
#include <linux/mfd/rohm-bd70528.h>
#include <linux/clk-provider.h>
#include <linux/clkdev.h>
#include <linux/regmap.h>
struct bd718xx_clk {
struct clk_hw hw;
u8 reg;
u8 mask;
struct platform_device *pdev;
struct rohm_regmap_dev *mfd;
};
static int bd71837_clk_set(struct clk_hw *hw, int status)
{
struct bd718xx_clk *c = container_of(hw, struct bd718xx_clk, hw);
return regmap_update_bits(c->mfd->regmap, c->reg, c->mask, status);
}
static void bd71837_clk_disable(struct clk_hw *hw)
{
int rv;
struct bd718xx_clk *c = container_of(hw, struct bd718xx_clk, hw);
rv = bd71837_clk_set(hw, 0);
if (rv)
dev_dbg(&c->pdev->dev, "Failed to disable 32K clk (%d)\n", rv);
}
static int bd71837_clk_enable(struct clk_hw *hw)
{
return bd71837_clk_set(hw, 1);
}
static int bd71837_clk_is_enabled(struct clk_hw *hw)
{
int enabled;
int rval;
struct bd718xx_clk *c = container_of(hw, struct bd718xx_clk, hw);
rval = regmap_read(c->mfd->regmap, c->reg, &enabled);
if (rval)
return rval;
return enabled & c->mask;
}
static const struct clk_ops bd71837_clk_ops = {
.prepare = &bd71837_clk_enable,
.unprepare = &bd71837_clk_disable,
.is_prepared = &bd71837_clk_is_enabled,
};
static int bd71837_clk_probe(struct platform_device *pdev)
{
struct bd718xx_clk *c;
int rval = -ENOMEM;
const char *parent_clk;
struct device *parent = pdev->dev.parent;
struct rohm_regmap_dev *mfd = dev_get_drvdata(parent);
struct clk_init_data init = {
.name = "bd718xx-32k-out",
.ops = &bd71837_clk_ops,
};
c = devm_kzalloc(&pdev->dev, sizeof(*c), GFP_KERNEL);
if (!c)
return -ENOMEM;
init.num_parents = 1;
parent_clk = of_clk_get_parent_name(parent->of_node, 0);
init.parent_names = &parent_clk;
if (!parent_clk) {
dev_err(&pdev->dev, "No parent clk found\n");
return -EINVAL;
}
switch (mfd->chip_type) {
case ROHM_CHIP_TYPE_BD71837:
case ROHM_CHIP_TYPE_BD71847:
c->reg = BD718XX_REG_OUT32K;
c->mask = BD718XX_OUT32K_EN;
break;
case ROHM_CHIP_TYPE_BD70528:
c->reg = BD70528_REG_CLK_OUT;
c->mask = BD70528_CLK_OUT_EN_MASK;
break;
default:
dev_err(&pdev->dev, "Unknown clk chip\n");
return -EINVAL;
}
c->mfd = mfd;
c->pdev = pdev;
c->hw.init = &init;
of_property_read_string_index(parent->of_node,
"clock-output-names", 0, &init.name);
rval = devm_clk_hw_register(&pdev->dev, &c->hw);
if (rval) {
dev_err(&pdev->dev, "failed to register 32K clk");
return rval;
}
rval = devm_of_clk_add_hw_provider(&pdev->dev, of_clk_hw_simple_get,
&c->hw);
if (rval)
dev_err(&pdev->dev, "adding clk provider failed\n");
return rval;
}
static struct platform_driver bd71837_clk = {
.driver = {
.name = "bd718xx-clk",
},
.probe = bd71837_clk_probe,
};
module_platform_driver(bd71837_clk);
MODULE_AUTHOR("Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>");
MODULE_DESCRIPTION("BD71837/BD71847/BD70528 chip clk driver");
MODULE_LICENSE("GPL");