linux/drivers/clk/clk-bd718x7.c
Matti Vaittinen ae866dec74 clk: bd718x7: Support ROHM BD71828 clk block
BD71828GW is a single-chip power management IC for battery-powered portable
devices. Add support for controlling BD71828 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>
2020-01-24 07:22:47 +00:00

165 lines
3.9 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-generic.h>
#include <linux/clk-provider.h>
#include <linux/clkdev.h>
#include <linux/regmap.h>
/* clk control registers */
/* BD70528 */
#define BD70528_REG_OUT32K 0x2c
/* BD71828 */
#define BD71828_REG_OUT32K 0x4B
/* BD71837 and BD71847 */
#define BD718XX_REG_OUT32K 0x2E
/*
* BD71837, BD71847, BD70528 and BD71828 all use bit [0] to clk output control
*/
#define CLK_OUT_EN_MASK BIT(0)
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 bd718xx_clk *c, unsigned int status)
{
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(c, 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)
{
struct bd718xx_clk *c = container_of(hw, struct bd718xx_clk, hw);
return bd71837_clk_set(c, 0xffffffff);
}
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,
};
enum rohm_chip_type chip = platform_get_device_id(pdev)->driver_data;
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 (chip) {
case ROHM_CHIP_TYPE_BD71837:
case ROHM_CHIP_TYPE_BD71847:
c->reg = BD718XX_REG_OUT32K;
c->mask = CLK_OUT_EN_MASK;
break;
case ROHM_CHIP_TYPE_BD71828:
c->reg = BD71828_REG_OUT32K;
c->mask = CLK_OUT_EN_MASK;
break;
case ROHM_CHIP_TYPE_BD70528:
c->reg = BD70528_REG_OUT32K;
c->mask = 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 const struct platform_device_id bd718x7_clk_id[] = {
{ "bd71837-clk", ROHM_CHIP_TYPE_BD71837 },
{ "bd71847-clk", ROHM_CHIP_TYPE_BD71847 },
{ "bd70528-clk", ROHM_CHIP_TYPE_BD70528 },
{ "bd71828-clk", ROHM_CHIP_TYPE_BD71828 },
{ },
};
MODULE_DEVICE_TABLE(platform, bd718x7_clk_id);
static struct platform_driver bd71837_clk = {
.driver = {
.name = "bd718xx-clk",
},
.probe = bd71837_clk_probe,
.id_table = bd718x7_clk_id,
};
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");
MODULE_ALIAS("platform:bd718xx-clk");