drivers/net/wireless/ralink/rt2x00/rt2x00mmio.c

Source file repositories/reference/linux-study-clean/drivers/net/wireless/ralink/rt2x00/rt2x00mmio.c

File Facts

System
Linux kernel
Corpus path
drivers/net/wireless/ralink/rt2x00/rt2x00mmio.c
Extension
.c
Size
4372 bytes
Lines
202
Domain
Driver Families
Bucket
drivers/net
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

// SPDX-License-Identifier: GPL-2.0-or-later
/*
	Copyright (C) 2004 - 2009 Ivo van Doorn <IvDoorn@gmail.com>
	<http://rt2x00.serialmonkey.com>

 */

/*
	Module: rt2x00mmio
	Abstract: rt2x00 generic mmio device routines.
 */

#include <linux/dma-mapping.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>

#include "rt2x00.h"
#include "rt2x00mmio.h"

/*
 * Register access.
 */
int rt2x00mmio_regbusy_read(struct rt2x00_dev *rt2x00dev,
			    const unsigned int offset,
			    const struct rt2x00_field32 field,
			    u32 *reg)
{
	unsigned int i;

	if (!test_bit(DEVICE_STATE_PRESENT, &rt2x00dev->flags))
		return 0;

	for (i = 0; i < REGISTER_BUSY_COUNT; i++) {
		*reg = rt2x00mmio_register_read(rt2x00dev, offset);
		if (!rt2x00_get_field32(*reg, field))
			return 1;
		udelay(REGISTER_BUSY_DELAY);
	}

	printk_once(KERN_ERR "%s() Indirect register access failed: "
	      "offset=0x%.08x, value=0x%.08x\n", __func__, offset, *reg);
	*reg = ~0;

	return 0;
}
EXPORT_SYMBOL_GPL(rt2x00mmio_regbusy_read);

bool rt2x00mmio_rxdone(struct rt2x00_dev *rt2x00dev)
{
	struct data_queue *queue = rt2x00dev->rx;
	struct queue_entry *entry;
	struct queue_entry_priv_mmio *entry_priv;
	struct skb_frame_desc *skbdesc;
	int max_rx = 16;

	while (--max_rx) {
		entry = rt2x00queue_get_entry(queue, Q_INDEX);
		entry_priv = entry->priv_data;

		if (rt2x00dev->ops->lib->get_entry_state(entry))
			break;

		/*
		 * Fill in desc fields of the skb descriptor
		 */
		skbdesc = get_skb_frame_desc(entry->skb);
		skbdesc->desc = entry_priv->desc;
		skbdesc->desc_len = entry->queue->desc_size;

		/*
		 * DMA is already done, notify rt2x00lib that
		 * it finished successfully.
		 */
		rt2x00lib_dmastart(entry);
		rt2x00lib_dmadone(entry);

		/*
		 * Send the frame to rt2x00lib for further processing.
		 */
		rt2x00lib_rxdone(entry, GFP_ATOMIC);
	}

	return !max_rx;
}
EXPORT_SYMBOL_GPL(rt2x00mmio_rxdone);

void rt2x00mmio_flush_queue(struct data_queue *queue, bool drop)
{
	unsigned int i;

Annotation

Implementation Notes