smartcan.c

smartcan在linux操作系统下的驱动程序源代码。

/* smartcan.c
 * Linux CAN-bus device driver.
 * Written by Arnaud Westenberg email:[e-mail]
 * This software is released under the GPL-License.
 * Version 0.7  6 Aug 2001
 */ 

#include <linux/autoconf.h>
#if defined (CONFIG_MODVERSIONS) && !defined (MODVERSIONS)
#define MODVERSIONS
#endif

#if defined (MODVERSIONS)
#include <linux/modversions.h>
#endif

#include <linux/ioport.h>
#include <linux/delay.h>
#include <linux/sched.h>
#include <asm/errno.h>
#include <asm/io.h>
#include <asm/irq.h>
#include "sysdep.h"
#include "candrv.h"
#include "smartcan.h"
#include "i82527.h"

int smartcan_irq=-1;
unsigned long smartcan_base=0x0;

int smartcan_request_io(unsigned long io_addr)
{
	int err=0;

	if ( (err=check_region(io_addr,0x04)) < 0 ) {
		CANMSG("Unable to open port: 0x%lx\n",io_addr);
		return -ENODEV;
	}
	else {
		request_region(io_addr,0x04,DEVICE_NAME);
		DEBUGMSG("Registered IO-memory: 0x%lx - 0x%lx\n", io_addr, io_addr + 0x04 - 1);
	}
	return 0;
}

int smartcan_release_io(unsigned long io_addr)
{
	release_region(io_addr,0x04);

	return 0;
}

int smartcan_reset(int card)
{
	int i=0;

	DEBUGMSG("Resetting smartcan hardware ...\n");
	outb(0x00,candevices_p[card]->res_addr);
	while (i < 1000000) {
		i++;
		outb(0x01,candevices_p[card]->res_addr);
	}
	outb(0x00,candevices_p[card]->res_addr); 

	/* Check hardware reset status */
	i=0;
	outb(candevices_p[card]->io_addr+iCPU,candevices_p[card]->io_addr);
	while ( (inb(candevices_p[card]->io_addr+1)&0x80) && (i<=15) ) {
		udelay(20000);
		i++;
	}
	if (i>=15) {
		CANMSG("Reset status timeout!\n");
		CANMSG("Please check your hardware.\n");
		return -ENODEV;
	}
	else
		DEBUGMSG("Chip0 reset status ok.\n");

	return 0;
} 

int smartcan_init_hw_data(int card)
{
	candevices_p[card]->res_addr=candevices_p[card]->io_addr+0x02;
	candevices_p[card]->nr_82527_chips=1;
	candevices_p[card]->nr_sja1000_chips=0;

	return 0;
}

int smartcan_init_chip_data(int card, int chipnr)
{
	candevices_p[card]->chip[chipnr]->chip_type="i82527";
	candevices_p[card]->chip[chipnr]->chip_base_addr=candevices_p[card]->io_addr;
	candevices_p[card]->chip[chipnr]->clock = 16000000;
	candevices_p[card]->chip[chipnr]->int_cpu_reg = iCPU_DSC;
	candevices_p[card]->chip[chipnr]->int_clk_reg = iCLK_SL1;
	candevices_p[card]->chip[chipnr]->int_bus_reg = iBUS_CBY;
	candevices_p[card]->chip[chipnr]->sja_cdr_reg = 0;
	candevices_p[card]->chip[chipnr]->sja_ocr_reg = 0;
	smartcan_irq=candevices_p[card]->chip[chipnr]->chip_irq;
	smartcan_base=candevices_p[card]->chip[chipnr]->chip_base_addr;

	return 0;
}

int smartcan_init_obj_data(int chipnr, int objnr)
{
	chips_p[chipnr]->msgobj[objnr]->obj_base_addr=(objnr+1)*0x10;
	chips_p[chipnr]->msgobj[objnr]->flags=0;

	return 0;
}


void smartcan_write_register(unsigned char data, unsigned long address)
{
	disable_irq(smartcan_irq);
	outb(address-smartcan_base,smartcan_base);
	outb(data,smartcan_base+1);
	enable_irq(smartcan_irq);
}

unsigned smartcan_read_register(unsigned long address)
{
	unsigned ret;
	disable_irq(smartcan_irq);
	outb(address-smartcan_base,smartcan_base);
	ret=inb(smartcan_base+1);
	enable_irq(smartcan_irq);
	return ret;
}

int smartcan_program_irq(int card)
{
	CANMSG("The 'smartcan' card doesn't have programmable interrupts\n");
	return 0;
}

/* !!! Don't change this function !!! */
int smartcan_register(struct hwspecops_t *hwspecops)
{
	hwspecops->request_io = smartcan_request_io;
	hwspecops->release_io = smartcan_release_io;
	hwspecops->reset = smartcan_reset;
	hwspecops->init_hw_data = smartcan_init_hw_data;
	hwspecops->init_chip_data = smartcan_init_chip_data;
	hwspecops->init_obj_data = smartcan_init_obj_data;
	hwspecops->write_register = smartcan_write_register;
	hwspecops->read_register = smartcan_read_register;
	hwspecops->program_irq = smartcan_program_irq;
	return 0;
}