drivers/reset/reset-scmi.c

Source file repositories/reference/linux-study-clean/drivers/reset/reset-scmi.c

File Facts

System
Linux kernel
Corpus path
drivers/reset/reset-scmi.c
Extension
.c
Size
3637 bytes
Lines
133
Domain
Driver Families
Bucket
drivers/reset
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 scmi_reset_data {
	struct reset_controller_dev rcdev;
	const struct scmi_protocol_handle *ph;
};

#define to_scmi_reset_data(p)	container_of((p), struct scmi_reset_data, rcdev)
#define to_scmi_handle(p)	(to_scmi_reset_data(p)->ph)

/**
 * scmi_reset_assert() - assert device reset
 * @rcdev: reset controller entity
 * @id: ID of the reset to be asserted
 *
 * This function implements the reset driver op to assert a device's reset
 * using the ARM SCMI protocol.
 *
 * Return: 0 for successful request, else a corresponding error value
 */
static int
scmi_reset_assert(struct reset_controller_dev *rcdev, unsigned long id)
{
	const struct scmi_protocol_handle *ph = to_scmi_handle(rcdev);

	return reset_ops->assert(ph, id);
}

/**
 * scmi_reset_deassert() - deassert device reset
 * @rcdev: reset controller entity
 * @id: ID of the reset to be deasserted
 *
 * This function implements the reset driver op to deassert a device's reset
 * using the ARM SCMI protocol.
 *
 * Return: 0 for successful request, else a corresponding error value
 */
static int
scmi_reset_deassert(struct reset_controller_dev *rcdev, unsigned long id)
{
	const struct scmi_protocol_handle *ph = to_scmi_handle(rcdev);

	return reset_ops->deassert(ph, id);
}

/**
 * scmi_reset_reset() - reset the device
 * @rcdev: reset controller entity
 * @id: ID of the reset signal to be reset(assert + deassert)
 *
 * This function implements the reset driver op to trigger a device's
 * reset signal using the ARM SCMI protocol.
 *
 * Return: 0 for successful request, else a corresponding error value
 */
static int
scmi_reset_reset(struct reset_controller_dev *rcdev, unsigned long id)
{
	const struct scmi_protocol_handle *ph = to_scmi_handle(rcdev);

	return reset_ops->reset(ph, id);
}

static const struct reset_control_ops scmi_reset_ops = {
	.assert		= scmi_reset_assert,
	.deassert	= scmi_reset_deassert,
	.reset		= scmi_reset_reset,
};

static int scmi_reset_probe(struct scmi_device *sdev)
{
	struct scmi_reset_data *data;
	struct device *dev = &sdev->dev;
	struct device_node *np = dev->of_node;
	const struct scmi_handle *handle = sdev->handle;
	struct scmi_protocol_handle *ph;

	if (!handle)
		return -ENODEV;

	reset_ops = handle->devm_protocol_get(sdev, SCMI_PROTOCOL_RESET, &ph);
	if (IS_ERR(reset_ops))
		return PTR_ERR(reset_ops);

	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
	if (!data)
		return -ENOMEM;

	data->rcdev.ops = &scmi_reset_ops;
	data->rcdev.owner = THIS_MODULE;
	data->rcdev.of_node = np;

Annotation

Implementation Notes