arch/arm/mach-pxa/mfp-pxa3xx.c

Source file repositories/reference/linux-study-clean/arch/arm/mach-pxa/mfp-pxa3xx.c

File Facts

System
Linux kernel
Corpus path
arch/arm/mach-pxa/mfp-pxa3xx.c
Extension
.c
Size
1400 bytes
Lines
60
Domain
Architecture Layer
Bucket
arch/arm
Inferred role
Architecture Layer: implementation source
Status
source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0-only
/*
 * linux/arch/arm/mach-pxa/mfp.c
 *
 * PXA3xx Multi-Function Pin Support
 *
 * Copyright (C) 2007 Marvell Internation Ltd.
 *
 * 2007-08-21: eric miao <eric.miao@marvell.com>
 *             initial version
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/syscore_ops.h>

#include "mfp-pxa3xx.h"
#include "pxa3xx-regs.h"

#ifdef CONFIG_PM
/*
 * Configure the MFPs appropriately for suspend/resume.
 * FIXME: this should probably depend on which system state we're
 * entering - for instance, we might not want to place MFP pins in
 * a pull-down mode if they're an active low chip select, and we're
 * just entering standby.
 */
static int pxa3xx_mfp_suspend(void *data)
{
	mfp_config_lpm();
	return 0;
}

static void pxa3xx_mfp_resume(void *data)
{
	mfp_config_run();

	/* clear RDH bit when MFP settings are restored
	 *
	 * NOTE: the last 3 bits DxS are write-1-to-clear so carefully
	 * preserve them here in case they will be referenced later
	 */
	ASCR &= ~(ASCR_RDH | ASCR_D1S | ASCR_D2S | ASCR_D3S);
}
#else
#define pxa3xx_mfp_suspend	NULL
#define pxa3xx_mfp_resume	NULL
#endif

static const struct syscore_ops pxa3xx_mfp_syscore_ops = {
	.suspend	= pxa3xx_mfp_suspend,
	.resume		= pxa3xx_mfp_resume,
};

struct syscore pxa3xx_mfp_syscore = {
	.ops = &pxa3xx_mfp_syscore_ops,
};

Annotation

Implementation Notes