drivers/clk/clk-gpio.c

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

File Facts

System
Linux kernel
Corpus path
drivers/clk/clk-gpio.c
Extension
.c
Size
10952 bytes
Lines
427
Domain
Driver Families
Bucket
drivers/clk
Inferred role
Driver Families: implementation source
Status
source 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 clk_gpio {
	struct clk_hw	hw;
	struct gpio_desc *gpiod;
};

#define to_clk_gpio(_hw) container_of(_hw, struct clk_gpio, hw)

static int clk_gpio_gate_enable(struct clk_hw *hw)
{
	struct clk_gpio *clk = to_clk_gpio(hw);

	gpiod_set_value(clk->gpiod, 1);

	return 0;
}

static void clk_gpio_gate_disable(struct clk_hw *hw)
{
	struct clk_gpio *clk = to_clk_gpio(hw);

	gpiod_set_value(clk->gpiod, 0);
}

static int clk_gpio_gate_is_enabled(struct clk_hw *hw)
{
	struct clk_gpio *clk = to_clk_gpio(hw);

	return gpiod_get_value(clk->gpiod);
}

static const struct clk_ops clk_gpio_gate_ops = {
	.enable = clk_gpio_gate_enable,
	.disable = clk_gpio_gate_disable,
	.is_enabled = clk_gpio_gate_is_enabled,
};

static int clk_sleeping_gpio_gate_prepare(struct clk_hw *hw)
{
	struct clk_gpio *clk = to_clk_gpio(hw);

	gpiod_set_value_cansleep(clk->gpiod, 1);

	return 0;
}

static void clk_sleeping_gpio_gate_unprepare(struct clk_hw *hw)
{
	struct clk_gpio *clk = to_clk_gpio(hw);

	gpiod_set_value_cansleep(clk->gpiod, 0);
}

static int clk_sleeping_gpio_gate_is_prepared(struct clk_hw *hw)
{
	struct clk_gpio *clk = to_clk_gpio(hw);

	return gpiod_get_value_cansleep(clk->gpiod);
}

static const struct clk_ops clk_sleeping_gpio_gate_ops = {
	.prepare = clk_sleeping_gpio_gate_prepare,
	.unprepare = clk_sleeping_gpio_gate_unprepare,
	.is_prepared = clk_sleeping_gpio_gate_is_prepared,
};

/**
 * DOC: basic clock multiplexer which can be controlled with a gpio output
 * Traits of this clock:
 * prepare - clk_prepare only ensures that parents are prepared
 * rate - rate is only affected by parent switching.  No clk_set_rate support
 * parent - parent is adjustable through clk_set_parent
 */

static u8 clk_gpio_mux_get_parent(struct clk_hw *hw)
{
	struct clk_gpio *clk = to_clk_gpio(hw);

	return gpiod_get_value_cansleep(clk->gpiod);
}

static int clk_gpio_mux_set_parent(struct clk_hw *hw, u8 index)
{
	struct clk_gpio *clk = to_clk_gpio(hw);

	gpiod_set_value_cansleep(clk->gpiod, index);

	return 0;
}

static const struct clk_ops clk_gpio_mux_ops = {

Annotation

Implementation Notes