drivers/clk/mediatek/clk-cpumux.c

Source file repositories/reference/linux-study-clean/drivers/clk/mediatek/clk-cpumux.c

File Facts

System
Linux kernel
Corpus path
drivers/clk/mediatek/clk-cpumux.c
Extension
.c
Size
3749 bytes
Lines
174
Domain
Driver Families
Bucket
drivers/clk
Inferred role
Driver Families: exported/initcall integration point
Status
integration implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

struct mtk_clk_cpumux {
	struct clk_hw	hw;
	struct regmap	*regmap;
	u32		reg;
	u32		mask;
	u8		shift;
};

static inline struct mtk_clk_cpumux *to_mtk_clk_cpumux(struct clk_hw *_hw)
{
	return container_of(_hw, struct mtk_clk_cpumux, hw);
}

static u8 clk_cpumux_get_parent(struct clk_hw *hw)
{
	struct mtk_clk_cpumux *mux = to_mtk_clk_cpumux(hw);
	unsigned int val;

	regmap_read(mux->regmap, mux->reg, &val);

	val >>= mux->shift;
	val &= mux->mask;

	return val;
}

static int clk_cpumux_set_parent(struct clk_hw *hw, u8 index)
{
	struct mtk_clk_cpumux *mux = to_mtk_clk_cpumux(hw);
	u32 mask, val;

	val = index << mux->shift;
	mask = mux->mask << mux->shift;

	return regmap_update_bits(mux->regmap, mux->reg, mask, val);
}

static const struct clk_ops clk_cpumux_ops = {
	.determine_rate = clk_hw_determine_rate_no_reparent,
	.get_parent = clk_cpumux_get_parent,
	.set_parent = clk_cpumux_set_parent,
};

static struct clk_hw *
mtk_clk_register_cpumux(struct device *dev, const struct mtk_composite *mux,
			struct regmap *regmap)
{
	struct mtk_clk_cpumux *cpumux;
	int ret;
	struct clk_init_data init;

	cpumux = kzalloc_obj(*cpumux);
	if (!cpumux)
		return ERR_PTR(-ENOMEM);

	init.name = mux->name;
	init.ops = &clk_cpumux_ops;
	init.parent_names = mux->parent_names;
	init.num_parents = mux->num_parents;
	init.flags = mux->flags;

	cpumux->reg = mux->mux_reg;
	cpumux->shift = mux->mux_shift;
	cpumux->mask = BIT(mux->mux_width) - 1;
	cpumux->regmap = regmap;
	cpumux->hw.init = &init;

	ret = clk_hw_register(dev, &cpumux->hw);
	if (ret) {
		kfree(cpumux);
		return ERR_PTR(ret);
	}

	return &cpumux->hw;
}

static void mtk_clk_unregister_cpumux(struct clk_hw *hw)
{
	struct mtk_clk_cpumux *cpumux;
	if (!hw)
		return;

	cpumux = to_mtk_clk_cpumux(hw);

	clk_hw_unregister(hw);
	kfree(cpumux);
}

int mtk_clk_register_cpumuxes(struct device *dev, struct device_node *node,
			      const struct mtk_composite *clks, int num,

Annotation

Implementation Notes