drivers/power/sequencing/core.c

Source file repositories/reference/linux-study-clean/drivers/power/sequencing/core.c

File Facts

System
Linux kernel
Corpus path
drivers/power/sequencing/core.c
Extension
.c
Size
27715 bytes
Lines
1131
Domain
Driver Families
Bucket
drivers/power
Inferred role
Driver Families: operation-table or driver-model contract
Status
pattern 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

static const struct bus_type pwrseq_bus = {
	.name = "pwrseq",
};

static void pwrseq_release(struct device *dev)
{
	struct pwrseq_device *pwrseq = to_pwrseq_device(dev);
	struct pwrseq_target *target, *pos;

	list_for_each_entry_safe(target, pos, &pwrseq->targets, list) {
		list_del(&target->list);
		pwrseq_target_free(target);
	}

	mutex_destroy(&pwrseq->state_lock);
	ida_free(&pwrseq_ida, pwrseq->id);
	kfree(pwrseq);
}

static const struct device_type pwrseq_device_type = {
	.name = "power_sequencer",
	.release = pwrseq_release,
};

static int pwrseq_check_unit_deps(const struct pwrseq_unit_data *data,
				  struct radix_tree_root *visited_units)
{
	const struct pwrseq_unit_data *tmp, **cur;
	int ret;

	ret = radix_tree_insert(visited_units, (unsigned long)data,
				(void *)data);
	if (ret)
		return ret;

	for (cur = data->deps; cur && *cur; cur++) {
		tmp = radix_tree_lookup(visited_units, (unsigned long)*cur);
		if (tmp) {
			WARN(1, "Circular dependency in power sequencing flow detected!\n");
			return -EINVAL;
		}

		ret = pwrseq_check_unit_deps(*cur, visited_units);
		if (ret)
			return ret;
	}

	return 0;
}

static int pwrseq_check_target_deps(const struct pwrseq_target_data *data)
{
	struct radix_tree_root visited_units;
	struct radix_tree_iter iter;
	void __rcu **slot;
	int ret;

	if (!data->unit)
		return -EINVAL;

	INIT_RADIX_TREE(&visited_units, GFP_KERNEL);
	ret = pwrseq_check_unit_deps(data->unit, &visited_units);
	radix_tree_for_each_slot(slot, &visited_units, &iter, 0)
		radix_tree_delete(&visited_units, iter.index);

	return ret;
}

static int pwrseq_unit_setup_deps(const struct pwrseq_unit_data **data,
				  struct list_head *dep_list,
				  struct list_head *unit_list,
				  struct radix_tree_root *processed_units);

static struct pwrseq_unit *
pwrseq_unit_setup(const struct pwrseq_unit_data *data,
		  struct list_head *unit_list,
		  struct radix_tree_root *processed_units)
{
	struct pwrseq_unit *unit;
	int ret;

	unit = radix_tree_lookup(processed_units, (unsigned long)data);
	if (unit)
		return pwrseq_unit_get(unit);

	unit = pwrseq_unit_new(data);
	if (!unit)
		return ERR_PTR(-ENOMEM);

	if (data->deps) {

Annotation

Implementation Notes