drivers/platform/chrome/cros_ec_rpmsg.c

Source file repositories/reference/linux-study-clean/drivers/platform/chrome/cros_ec_rpmsg.c

File Facts

System
Linux kernel
Corpus path
drivers/platform/chrome/cros_ec_rpmsg.c
Extension
.c
Size
7694 bytes
Lines
306
Domain
Driver Families
Bucket
drivers/platform
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 cros_ec_rpmsg_response {
	u8 type;
	u8 data[] __aligned(4);
};

/**
 * struct cros_ec_rpmsg - information about a EC over rpmsg.
 *
 * @rpdev:	rpmsg device we are connected to
 * @xfer_ack:	completion for host command transfer.
 * @host_event_work:	Work struct for pending host event.
 * @ept: The rpmsg endpoint of this channel.
 * @has_pending_host_event: Boolean used to check if there is a pending event.
 * @probe_done: Flag to indicate that probe is done.
 */
struct cros_ec_rpmsg {
	struct rpmsg_device *rpdev;
	struct completion xfer_ack;
	struct work_struct host_event_work;
	struct rpmsg_endpoint *ept;
	bool has_pending_host_event;
	bool probe_done;
};

/**
 * cros_ec_cmd_xfer_rpmsg - Transfer a message over rpmsg and receive the reply
 *
 * @ec_dev: ChromeOS EC device
 * @ec_msg: Message to transfer
 *
 * This is only used for old EC proto version, and is not supported for this
 * driver.
 *
 * Return: -EINVAL
 */
static int cros_ec_cmd_xfer_rpmsg(struct cros_ec_device *ec_dev,
				  struct cros_ec_command *ec_msg)
{
	return -EINVAL;
}

/**
 * cros_ec_pkt_xfer_rpmsg - Transfer a packet over rpmsg and receive the reply
 *
 * @ec_dev: ChromeOS EC device
 * @ec_msg: Message to transfer
 *
 * Return: number of bytes of the reply on success or negative error code.
 */
static int cros_ec_pkt_xfer_rpmsg(struct cros_ec_device *ec_dev,
				  struct cros_ec_command *ec_msg)
{
	struct cros_ec_rpmsg *ec_rpmsg = ec_dev->priv;
	struct ec_host_response *response;
	unsigned long timeout;
	int len;
	int ret;
	u8 sum;
	int i;

	ec_msg->result = 0;
	len = cros_ec_prepare_tx(ec_dev, ec_msg);
	if (len < 0)
		return len;
	dev_dbg(ec_dev->dev, "prepared, len=%d\n", len);

	reinit_completion(&ec_rpmsg->xfer_ack);
	ret = rpmsg_send(ec_rpmsg->ept, ec_dev->dout, len);
	if (ret) {
		dev_err(ec_dev->dev, "rpmsg send failed\n");
		return ret;
	}

	timeout = msecs_to_jiffies(EC_MSG_TIMEOUT_MS);
	ret = wait_for_completion_timeout(&ec_rpmsg->xfer_ack, timeout);
	if (!ret) {
		dev_err(ec_dev->dev, "rpmsg send timeout\n");
		return -EIO;
	}

	/* check response error code */
	response = (struct ec_host_response *)ec_dev->din;
	ec_msg->result = response->result;

	ret = cros_ec_check_result(ec_dev, ec_msg);
	if (ret)
		goto exit;

	if (response->data_len > ec_msg->insize) {
		dev_err(ec_dev->dev, "packet too long (%d bytes, expected %d)",

Annotation

Implementation Notes