drivers/misc/mei/hw-me.c

Source file repositories/reference/linux-study-clean/drivers/misc/mei/hw-me.c

File Facts

System
Linux kernel
Corpus path
drivers/misc/mei/hw-me.c
Extension
.c
Size
42443 bytes
Lines
1820
Domain
Driver Families
Bucket
drivers/misc
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

if (!(reg & H_D0I3C_I3)) {
			ret = -ETIME;
			goto out;
		}
	}

	ret = 0;
on:
	hw->pg_state = MEI_PG_ON;
out:
	dev->pg_event = MEI_PG_EVENT_IDLE;
	dev_dbg(&dev->dev, "d0i3 enter ret = %d\n", ret);
	return ret;
}

/**
 * mei_me_d0i3_enter - perform d0i3 entry procedure
 *   no hbm PG handshake
 *   no waiting for confirmation; runs with interrupts
 *   disabled
 *
 * @dev: the device structure
 *
 * Return: 0 on success an error code otherwise
 */
static int mei_me_d0i3_enter(struct mei_device *dev)
{
	struct mei_me_hw *hw = to_me_hw(dev);
	u32 reg;

	reg = mei_me_d0i3c_read(dev);
	if (reg & H_D0I3C_I3) {
		/* we are in d0i3, nothing to do */
		dev_dbg(&dev->dev, "already d0i3 : set not needed\n");
		goto on;
	}

	mei_me_d0i3_set(dev, false);
on:
	hw->pg_state = MEI_PG_ON;
	dev->pg_event = MEI_PG_EVENT_IDLE;
	dev_dbg(&dev->dev, "d0i3 enter\n");
	return 0;
}

/**
 * mei_me_d0i3_exit_sync - perform d0i3 exit procedure
 *
 * @dev: the device structure
 *
 * Return: 0 on success an error code otherwise
 */
static int mei_me_d0i3_exit_sync(struct mei_device *dev)
{
	struct mei_me_hw *hw = to_me_hw(dev);
	int ret;
	u32 reg;

	dev->pg_event = MEI_PG_EVENT_INTR_WAIT;

	reg = mei_me_d0i3c_read(dev);
	if (!(reg & H_D0I3C_I3)) {
		/* we are not in d0i3, nothing to do */
		dev_dbg(&dev->dev, "d0i3 exit not needed\n");
		ret = 0;
		goto off;
	}

	reg = mei_me_d0i3_unset(dev);
	if (!(reg & H_D0I3C_CIP)) {
		dev_dbg(&dev->dev, "d0i3 exit wait not needed\n");
		ret = 0;
		goto off;
	}

	mutex_unlock(&dev->device_lock);
	wait_event_timeout(dev->wait_pg,
		dev->pg_event == MEI_PG_EVENT_INTR_RECEIVED,
		dev->timeouts.d0i3);
	mutex_lock(&dev->device_lock);

	if (dev->pg_event != MEI_PG_EVENT_INTR_RECEIVED) {
		reg = mei_me_d0i3c_read(dev);
		if (reg & H_D0I3C_I3) {
			ret = -ETIME;
			goto out;
		}
	}

	ret = 0;

Annotation

Implementation Notes