drivers/clk/sunxi-ng/ccu_gate.c

Source file repositories/reference/linux-study-clean/drivers/clk/sunxi-ng/ccu_gate.c

File Facts

System
Linux kernel
Corpus path
drivers/clk/sunxi-ng/ccu_gate.c
Extension
.c
Size
3188 bytes
Lines
137
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

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (C) 2016 Maxime Ripard
 * Maxime Ripard <maxime.ripard@free-electrons.com>
 */

#include <linux/clk-provider.h>
#include <linux/io.h>

#include "ccu_gate.h"

void ccu_gate_helper_disable(struct ccu_common *common, u32 gate)
{
	unsigned long flags;
	u32 reg;

	if (!gate)
		return;

	spin_lock_irqsave(common->lock, flags);

	reg = readl(common->base + common->reg);
	if (common->features & CCU_FEATURE_UPDATE_BIT)
		reg |= CCU_SUNXI_UPDATE_BIT;
	writel(reg & ~gate, common->base + common->reg);

	spin_unlock_irqrestore(common->lock, flags);
}
EXPORT_SYMBOL_NS_GPL(ccu_gate_helper_disable, "SUNXI_CCU");

static void ccu_gate_disable(struct clk_hw *hw)
{
	struct ccu_gate *cg = hw_to_ccu_gate(hw);

	return ccu_gate_helper_disable(&cg->common, cg->enable);
}

int ccu_gate_helper_enable(struct ccu_common *common, u32 gate)
{
	unsigned long flags;
	u32 reg;

	if (!gate)
		return 0;

	spin_lock_irqsave(common->lock, flags);

	reg = readl(common->base + common->reg);
	if (common->features & CCU_FEATURE_UPDATE_BIT)
		reg |= CCU_SUNXI_UPDATE_BIT;
	writel(reg | gate, common->base + common->reg);

	spin_unlock_irqrestore(common->lock, flags);

	return 0;
}
EXPORT_SYMBOL_NS_GPL(ccu_gate_helper_enable, "SUNXI_CCU");

static int ccu_gate_enable(struct clk_hw *hw)
{
	struct ccu_gate *cg = hw_to_ccu_gate(hw);

	return ccu_gate_helper_enable(&cg->common, cg->enable);
}

int ccu_gate_helper_is_enabled(struct ccu_common *common, u32 gate)
{
	if (!gate)
		return 1;

	return readl(common->base + common->reg) & gate;
}
EXPORT_SYMBOL_NS_GPL(ccu_gate_helper_is_enabled, "SUNXI_CCU");

static int ccu_gate_is_enabled(struct clk_hw *hw)
{
	struct ccu_gate *cg = hw_to_ccu_gate(hw);

	return ccu_gate_helper_is_enabled(&cg->common, cg->enable);
}

static unsigned long ccu_gate_recalc_rate(struct clk_hw *hw,
					  unsigned long parent_rate)
{
	struct ccu_gate *cg = hw_to_ccu_gate(hw);
	unsigned long rate = parent_rate;

	if (cg->common.features & CCU_FEATURE_ALL_PREDIV)
		rate /= cg->common.prediv;

Annotation

Implementation Notes