sound/aoa/soundbus/i2sbus/control.c

Source file repositories/reference/linux-study-clean/sound/aoa/soundbus/i2sbus/control.c

File Facts

System
Linux kernel
Corpus path
sound/aoa/soundbus/i2sbus/control.c
Extension
.c
Size
4551 bytes
Lines
193
Domain
Driver Families
Bucket
sound/aoa
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-only
/*
 * i2sbus driver -- bus control routines
 *
 * Copyright 2006 Johannes Berg <johannes@sipsolutions.net>
 */

#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/io.h>

#include <asm/macio.h>
#include <asm/pmac_feature.h>
#include <asm/pmac_pfunc.h>
#include <asm/keylargo.h>

#include "i2sbus.h"

int i2sbus_control_init(struct macio_dev* dev, struct i2sbus_control **c)
{
	*c = kzalloc_obj(struct i2sbus_control);
	if (!*c)
		return -ENOMEM;

	INIT_LIST_HEAD(&(*c)->list);

	(*c)->macio = dev->bus->chip;
	return 0;
}

void i2sbus_control_destroy(struct i2sbus_control *c)
{
	kfree(c);
}

/* this is serialised externally */
int i2sbus_control_add_dev(struct i2sbus_control *c,
			   struct i2sbus_dev *i2sdev)
{
	struct device_node *np;

	np = i2sdev->sound.ofdev.dev.of_node;
	i2sdev->enable = pmf_find_function(np, "enable");
	i2sdev->cell_enable = pmf_find_function(np, "cell-enable");
	i2sdev->clock_enable = pmf_find_function(np, "clock-enable");
	i2sdev->cell_disable = pmf_find_function(np, "cell-disable");
	i2sdev->clock_disable = pmf_find_function(np, "clock-disable");

	/* if the bus number is not 0 or 1 we absolutely need to use
	 * the platform functions -- there's nothing in Darwin that
	 * would allow seeing a system behind what the FCRs are then,
	 * and I don't want to go parsing a bunch of platform functions
	 * by hand to try finding a system... */
	if (i2sdev->bus_number != 0 && i2sdev->bus_number != 1 &&
	    (!i2sdev->enable ||
	     !i2sdev->cell_enable || !i2sdev->clock_enable ||
	     !i2sdev->cell_disable || !i2sdev->clock_disable)) {
		pmf_put_function(i2sdev->enable);
		pmf_put_function(i2sdev->cell_enable);
		pmf_put_function(i2sdev->clock_enable);
		pmf_put_function(i2sdev->cell_disable);
		pmf_put_function(i2sdev->clock_disable);
		return -ENODEV;
	}

	list_add(&i2sdev->item, &c->list);

	return 0;
}

void i2sbus_control_remove_dev(struct i2sbus_control *c,
			       struct i2sbus_dev *i2sdev)
{
	/* this is serialised externally */
	list_del(&i2sdev->item);
	if (list_empty(&c->list))
		i2sbus_control_destroy(c);
}

int i2sbus_control_enable(struct i2sbus_control *c,
			  struct i2sbus_dev *i2sdev)
{
	struct pmf_args args = { .count = 0 };
	struct macio_chip *macio = c->macio;

	if (i2sdev->enable)
		return pmf_call_one(i2sdev->enable, &args);

	if (macio == NULL || macio->base == NULL)

Annotation

Implementation Notes