drivers/bus/fsl-mc/dpmcp.c

Source file repositories/reference/linux-study-clean/drivers/bus/fsl-mc/dpmcp.c

File Facts

System
Linux kernel
Corpus path
drivers/bus/fsl-mc/dpmcp.c
Extension
.c
Size
2133 bytes
Lines
78
Domain
Driver Families
Bucket
drivers/bus
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

// SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
/*
 * Copyright 2013-2016 Freescale Semiconductor Inc.
 *
 */
#include <linux/kernel.h>
#include <linux/fsl/mc.h>

#include "fsl-mc-private.h"

/**
 * dpmcp_open() - Open a control session for the specified object.
 * @mc_io:	Pointer to MC portal's I/O object
 * @cmd_flags:	Command flags; one or more of 'MC_CMD_FLAG_'
 * @dpmcp_id:	DPMCP unique ID
 * @token:	Returned token; use in subsequent API calls
 *
 * This function can be used to open a control session for an
 * already created object; an object may have been declared in
 * the DPL or by calling the dpmcp_create function.
 * This function returns a unique authentication token,
 * associated with the specific object ID and the specific MC
 * portal; this token must be used in all subsequent commands for
 * this specific object
 *
 * Return:	'0' on Success; Error code otherwise.
 */
int dpmcp_open(struct fsl_mc_io *mc_io,
	       u32 cmd_flags,
	       int dpmcp_id,
	       u16 *token)
{
	struct fsl_mc_command cmd = { 0 };
	struct dpmcp_cmd_open *cmd_params;
	int err;

	/* prepare command */
	cmd.header = mc_encode_cmd_header(DPMCP_CMDID_OPEN,
					  cmd_flags, 0);
	cmd_params = (struct dpmcp_cmd_open *)cmd.params;
	cmd_params->dpmcp_id = cpu_to_le32(dpmcp_id);

	/* send command to mc*/
	err = mc_send_command(mc_io, &cmd);
	if (err)
		return err;

	/* retrieve response parameters */
	*token = mc_cmd_hdr_read_token(&cmd);

	return err;
}

/**
 * dpmcp_close() - Close the control session of the object
 * @mc_io:	Pointer to MC portal's I/O object
 * @cmd_flags:	Command flags; one or more of 'MC_CMD_FLAG_'
 * @token:	Token of DPMCP object
 *
 * After this function is called, no further operations are
 * allowed on the object without opening a new control session.
 *
 * Return:	'0' on Success; Error code otherwise.
 */
int dpmcp_close(struct fsl_mc_io *mc_io,
		u32 cmd_flags,
		u16 token)
{
	struct fsl_mc_command cmd = { 0 };

	/* prepare command */
	cmd.header = mc_encode_cmd_header(DPMCP_CMDID_CLOSE,
					  cmd_flags, token);

	/* send command to mc*/
	return mc_send_command(mc_io, &cmd);
}

Annotation

Implementation Notes