drivers/net/wan/slic_ds26522.c

Source file repositories/reference/linux-study-clean/drivers/net/wan/slic_ds26522.c

File Facts

System
Linux kernel
Corpus path
drivers/net/wan/slic_ds26522.c
Extension
.c
Size
6265 bytes
Lines
246
Domain
Driver Families
Bucket
drivers/net
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-later
/*
 * drivers/net/wan/slic_ds26522.c
 *
 * Copyright (C) 2016 Freescale Semiconductor, Inc.
 *
 * Author:Zhao Qiang<qiang.zhao@nxp.com>
 */

#include <linux/bitrev.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/kthread.h>
#include <linux/spi/spi.h>
#include <linux/wait.h>
#include <linux/param.h>
#include <linux/delay.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/io.h>
#include "slic_ds26522.h"

#define SLIC_TRANS_LEN 1
#define SLIC_TWO_LEN 2
#define SLIC_THREE_LEN 3

static struct spi_device *g_spi;

MODULE_DESCRIPTION("Slic Maxim DS26522 driver");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Zhao Qiang<B45475@freescale.com>");

/* the read/write format of address is
 * w/r|A13|A12|A11|A10|A9|A8|A7|A6|A5|A4|A3|A2|A1|A0|x
 */
static void slic_write(struct spi_device *spi, u16 addr,
		       u8 data)
{
	u8 temp[3];

	addr = bitrev16(addr) >> 1;
	data = bitrev8(data);
	temp[0] = (u8)((addr >> 8) & 0x7f);
	temp[1] = (u8)(addr & 0xfe);
	temp[2] = data;

	/* write spi addr and value */
	spi_write(spi, &temp[0], SLIC_THREE_LEN);
}

static u8 slic_read(struct spi_device *spi, u16 addr)
{
	u8 temp[2];
	u8 data;

	addr = bitrev16(addr) >> 1;
	temp[0] = (u8)(((addr >> 8) & 0x7f) | 0x80);
	temp[1] = (u8)(addr & 0xfe);

	spi_write_then_read(spi, &temp[0], SLIC_TWO_LEN, &data,
			    SLIC_TRANS_LEN);

	data = bitrev8(data);
	return data;
}

static bool get_slic_product_code(struct spi_device *spi)
{
	u8 device_id;

	device_id = slic_read(spi, DS26522_IDR_ADDR);
	if ((device_id & 0xf8) == 0x68)
		return true;
	else
		return false;
}

static void ds26522_e1_spec_config(struct spi_device *spi)
{
	/* Receive E1 Mode, Framer Disabled */
	slic_write(spi, DS26522_RMMR_ADDR, DS26522_RMMR_E1);

	/* Transmit E1 Mode, Framer Disable */
	slic_write(spi, DS26522_TMMR_ADDR, DS26522_TMMR_E1);

	/* Receive E1 Mode Framer Enable */
	slic_write(spi, DS26522_RMMR_ADDR,
		   slic_read(spi, DS26522_RMMR_ADDR) | DS26522_RMMR_FRM_EN);

Annotation

Implementation Notes