drivers/hwspinlock/qcom_hwspinlock.c

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

File Facts

System
Linux kernel
Corpus path
drivers/hwspinlock/qcom_hwspinlock.c
Extension
.c
Size
6445 bytes
Lines
261
Domain
Driver Families
Bucket
drivers/hwspinlock
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 qcom_hwspinlock_of_data {
	u32 offset;
	u32 stride;
	const struct regmap_config *regmap_config;
};

static int qcom_hwspinlock_trylock(struct hwspinlock *lock)
{
	struct regmap_field *field = lock->priv;
	u32 lock_owner;
	int ret;

	ret = regmap_field_write(field, QCOM_MUTEX_APPS_PROC_ID);
	if (ret)
		return ret;

	ret = regmap_field_read(field, &lock_owner);
	if (ret)
		return ret;

	return lock_owner == QCOM_MUTEX_APPS_PROC_ID;
}

static void qcom_hwspinlock_unlock(struct hwspinlock *lock)
{
	struct regmap_field *field = lock->priv;
	u32 lock_owner;
	int ret;

	ret = regmap_field_read(field, &lock_owner);
	if (ret) {
		pr_err("%s: unable to query spinlock owner\n", __func__);
		return;
	}

	if (lock_owner != QCOM_MUTEX_APPS_PROC_ID) {
		pr_err("%s: spinlock not owned by us (actual owner is %d)\n",
				__func__, lock_owner);
	}

	ret = regmap_field_write(field, 0);
	if (ret)
		pr_err("%s: failed to unlock spinlock\n", __func__);
}

static int qcom_hwspinlock_bust(struct hwspinlock *lock, unsigned int id)
{
	struct regmap_field *field = lock->priv;
	u32 owner;
	int ret;

	ret = regmap_field_read(field, &owner);
	if (ret) {
		dev_err(lock->bank->dev, "unable to query spinlock owner\n");
		return ret;
	}

	if (owner != id)
		return 0;

	ret = regmap_field_write(field, 0);
	if (ret) {
		dev_err(lock->bank->dev, "failed to bust spinlock\n");
		return ret;
	}

	return 0;
}

static const struct hwspinlock_ops qcom_hwspinlock_ops = {
	.trylock	= qcom_hwspinlock_trylock,
	.unlock		= qcom_hwspinlock_unlock,
	.bust		= qcom_hwspinlock_bust,
};

static const struct regmap_config sfpb_mutex_config = {
	.reg_bits		= 32,
	.reg_stride		= 4,
	.val_bits		= 32,
	.max_register		= 0x100,
	.fast_io		= true,
};

static const struct qcom_hwspinlock_of_data of_sfpb_mutex = {
	.offset = 0x4,
	.stride = 0x4,
	.regmap_config = &sfpb_mutex_config,
};

static const struct regmap_config tcsr_msm8226_mutex_config = {

Annotation

Implementation Notes