fit3.c

Linux块设备驱动源码

/* 
        fit3.c        (c) 1998  Grant R. Guenther <[e-mail]>
                          Under the terms of the GNU General Public License.

	fit3.c is a low-level protocol driver for newer models 
        of the Fidelity International Technology parallel port adapter.  
	This adapter is used in their TransDisk 3000 portable 
	hard-drives, as well as CD-ROM, PD-CD and other devices.

	The TD-2000 and certain older devices use a different protocol.
	Try the fit2 protocol module with them.

        NB:  The FIT adapters do not appear to support the control 
	registers.  So, we map ALT_STATUS to STATUS and NO-OP writes 
	to the device control register - this means that IDE reset 
	will not work on these devices.

*/

#define FIT3_VERSION      "1.0"

#include <linux/module.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/wait.h>
#include <asm/io.h>

#include "paride.h"

#define j44(a,b)                (((a>>3)&0x0f)|((b<<1)&0xf0))

#define w7(byte)                {out_p(7,byte);}
#define r7()                    (in_p(7) & 0xff)

/* cont = 0 - access the IDE register file 
   cont = 1 - access the IDE command set 

*/

static void  fit3_write_regr( PIA *pi, int cont, int regr, int val)

{	if (cont == 1) return;

	switch (pi->mode) {

	case 0:
	case 1: w2(0xc); w0(regr); w2(0x8); w2(0xc); 
		w0(val); w2(0xd); 
		w0(0);   w2(0xc);
		break;

	case 2: w2(0xc); w0(regr); w2(0x8); w2(0xc);
		w4(val); w4(0);
		w2(0xc);
		break;

	}
}

static int fit3_read_regr( PIA *pi, int cont, int regr )

{	int  a, b;

	if (cont) {
	  if (regr != 6) return 0xff;
	  regr = 7;
	} 

	switch (pi->mode) {

	case 0: w2(0xc); w0(regr + 0x10); w2(0x8); w2(0xc);
		w2(0xd); a = r1();
		w2(0xf); b = r1(); 
		w2(0xc);
		return j44(a,b);

	case 1: w2(0xc); w0(regr + 0x90); w2(0x8); w2(0xc);
		w2(0xec); w2(0xee); w2(0xef); a = r0(); 
		w2(0xc);
		return a;

	case 2: w2(0xc); w0(regr + 0x90); w2(0x8); w2(0xc); 
		w2(0xec); 
		a = r4(); b = r4(); 
		w2(0xc);
		return a;

	}
	return -1; 

}

static void fit3_read_block( PIA *pi, char * buf, int count )

{	int  k, a, b, c, d;

	switch (pi->mode) {

	case 0: w2(0xc); w0(0x10); w2(0x8); w2(0xc);
		for (k=0;k<count/2;k++) {
		    w2(0xd); a = r1();
		    w2(0xf); b = r1();
		    w2(0xc); c = r1();
		    w2(0xe); d = r1();
		    buf[2*k  ] = j44(a,b);
		    buf[2*k+1] = j44(c,d);
		}
		w2(0xc);
		break;

	case 1: w2(0xc); w0(0x90); w2(0x8); w2(0xc); 
		w2(0xec); w2(0xee);
		for (k=0;k<count/2;k++) {
		    w2(0xef); a = r0();
		    w2(0xee); b = r0();
                    buf[2*k  ] = a;
                    buf[2*k+1] = b;
		}
		w2(0xec); 
		w2(0xc);
		break;

	case 2: w2(0xc); w0(0x90); w2(0x8); w2(0xc); 
                w2(0xec);
		for (k=0;k<count;k++) buf[k] = r4();
                w2(0xc);
		break;

	}
}

static void fit3_write_block( PIA *pi, char * buf, int count )

{	int k;

        switch (pi->mode) {

	case 0:
        case 1: w2(0xc); w0(0); w2(0x8); w2(0xc);
                for (k=0;k<count/2;k++) {
 		    w0(buf[2*k  ]); w2(0xd);
 		    w0(buf[2*k+1]); w2(0xc);
		}
		break;

        case 2: w2(0xc); w0(0); w2(0x8); w2(0xc); 
                for (k=0;k<count;k++) w4(buf[k]);
                w2(0xc);
		break;
	}
}

static void fit3_connect ( PIA *pi  )

{       pi->saved_r0 = r0();
        pi->saved_r2 = r2();
	w2(0xc); w0(0); w2(0xa);
	if (pi->mode == 2) { 
		w2(0xc); w0(0x9); w2(0x8); w2(0xc); 
		}
}

static void fit3_disconnect ( PIA *pi )

{       w2(0xc); w0(0xa); w2(0x8); w2(0xc);
	w0(pi->saved_r0);
        w2(pi->saved_r2);
} 

static void fit3_log_adapter( PIA *pi, char * scratch, int verbose )

{       char    *mode_string[3] = {"4-bit","8-bit","EPP"};

	printk("%s: fit3 %s, FIT 3000 adapter at 0x%x, "
	       "mode %d (%s), delay %d\n",
                pi->device,FIT3_VERSION,pi->port,
		pi->mode,mode_string[pi->mode],pi->delay);

}

static struct pi_protocol fit3 = {
	.owner		= THIS_MODULE,
	.name		= "fit3",
	.max_mode	= 3,
	.epp_first	= 2,
	.default_delay	= 1,
	.max_units	= 1,
	.write_regr	= fit3_write_regr,
	.read_regr	= fit3_read_regr,
	.write_block	= fit3_write_block,
	.read_block	= fit3_read_block,
	.connect	= fit3_connect,
	.disconnect	= fit3_disconnect,
	.log_adapter	= fit3_log_adapter,
};

static int __init fit3_init(void)
{
	return pi_register(&fit3)-1;
}

static void __exit fit3_exit(void)
{
	pi_unregister(&fit3);
}

MODULE_LICENSE("GPL");
module_init(fit3_init)
module_exit(fit3_exit)