drivers/hwspinlock/sun6i_hwspinlock.c

Source file repositories/reference/linux-study-clean/drivers/hwspinlock/sun6i_hwspinlock.c

File Facts

System
Linux kernel
Corpus path
drivers/hwspinlock/sun6i_hwspinlock.c
Extension
.c
Size
5740 bytes
Lines
211
Domain
Driver Families
Bucket
drivers/hwspinlock
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 sun6i_hwspinlock_data {
	struct hwspinlock_device *bank;
	struct reset_control *reset;
	struct clk *ahb_clk;
	struct dentry *debugfs;
	int nlocks;
};

#ifdef CONFIG_DEBUG_FS

static int hwlocks_supported_show(struct seq_file *seqf, void *unused)
{
	struct sun6i_hwspinlock_data *priv = seqf->private;

	seq_printf(seqf, "%d\n", priv->nlocks);

	return 0;
}
DEFINE_SHOW_ATTRIBUTE(hwlocks_supported);

static void sun6i_hwspinlock_debugfs_init(struct sun6i_hwspinlock_data *priv)
{
	priv->debugfs = debugfs_create_dir(DRIVER_NAME, NULL);
	debugfs_create_file("supported", 0444, priv->debugfs, priv, &hwlocks_supported_fops);
}

#else

static void sun6i_hwspinlock_debugfs_init(struct sun6i_hwspinlock_data *priv)
{
}

#endif

static int sun6i_hwspinlock_trylock(struct hwspinlock *lock)
{
	void __iomem *lock_addr = lock->priv;

	return (readl(lock_addr) == SPINLOCK_NOTTAKEN);
}

static void sun6i_hwspinlock_unlock(struct hwspinlock *lock)
{
	void __iomem *lock_addr = lock->priv;

	writel(SPINLOCK_NOTTAKEN, lock_addr);
}

static const struct hwspinlock_ops sun6i_hwspinlock_ops = {
	.trylock	= sun6i_hwspinlock_trylock,
	.unlock		= sun6i_hwspinlock_unlock,
};

static void sun6i_hwspinlock_disable(void *data)
{
	struct sun6i_hwspinlock_data *priv = data;

	debugfs_remove_recursive(priv->debugfs);
	clk_disable_unprepare(priv->ahb_clk);
	reset_control_assert(priv->reset);
}

static int sun6i_hwspinlock_probe(struct platform_device *pdev)
{
	struct sun6i_hwspinlock_data *priv;
	struct hwspinlock *hwlock;
	void __iomem *io_base;
	u32 num_banks;
	int err, i;

	io_base = devm_platform_ioremap_resource(pdev, SPINLOCK_BASE_ID);
	if (IS_ERR(io_base))
		return PTR_ERR(io_base);

	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
	if (!priv)
		return -ENOMEM;

	priv->ahb_clk = devm_clk_get(&pdev->dev, "ahb");
	if (IS_ERR(priv->ahb_clk)) {
		err = PTR_ERR(priv->ahb_clk);
		dev_err(&pdev->dev, "unable to get AHB clock (%d)\n", err);
		return err;
	}

	priv->reset = devm_reset_control_get(&pdev->dev, "ahb");
	if (IS_ERR(priv->reset))
		return dev_err_probe(&pdev->dev, PTR_ERR(priv->reset),
				     "unable to get reset control\n");

Annotation

Implementation Notes