aztcd.c

还有没有人研究过cdrom 的驱动源码啊

#define AZT_VERSION "2.60"

/*      $Id: aztcd.c,v 2.60 1997/11/29 09:51:19 root Exp root $
	linux/drivers/block/aztcd.c - Aztech CD268 CDROM driver

	Copyright (C) 1994-98 Werner Zimmermann([e-mail])

	based on Mitsumi CDROM driver by  Martin Hariss and preworks by
	Eberhard Moenkeberg; contains contributions by Joe Nardone and Robby 
	Schirmer.

	This program is free software; you can redistribute it and/or modify
	it under the terms of the GNU General Public License as published by
	the Free Software Foundation; either version 2, or (at your option)
	any later version.

	This program is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
	GNU General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with this program; if not, write to the Free Software
	Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

	HISTORY
	V0.0    Adaption to Aztech CD268-01A Version 1.3
		Version is PRE_ALPHA, unresolved points:
		1. I use busy wait instead of timer wait in STEN_LOW,DTEN_LOW
		   thus driver causes CPU overhead and is very slow 
		2. could not find a way to stop the drive, when it is
		   in data read mode, therefore I had to set
		   msf.end.min/sec/frame to 0:0:1 (in azt_poll); so only one
		   frame can be read in sequence, this is also the reason for
		3. getting 'timeout in state 4' messages, but nevertheless
		   it works
		W.Zimmermann, Oct. 31, 1994
	V0.1    Version is ALPHA, problems #2 and #3 resolved.  
		W.Zimmermann, Nov. 3, 1994
	V0.2    Modification to some comments, debugging aids for partial test
		with Borland C under DOS eliminated. Timer interrupt wait 
		STEN_LOW_WAIT additionally to busy wait for STEN_LOW implemented; 
		use it only for the 'slow' commands (ACMD_GET_Q_CHANNEL, ACMD_
		SEEK_TO_LEAD_IN), all other commands are so 'fast', that busy 
		waiting seems better to me than interrupt rescheduling.
		Besides that, when used in the wrong place, STEN_LOW_WAIT causes
		kernel panic.
		In function aztPlay command ACMD_PLAY_AUDIO added, should make
		audio functions work. The Aztech drive needs different commands
		to read data tracks and play audio tracks.
		W.Zimmermann, Nov. 8, 1994
	V0.3    Recognition of missing drive during boot up improved (speeded up).
		W.Zimmermann, Nov. 13, 1994
	V0.35   Rewrote the control mechanism in azt_poll (formerly mcd_poll) 
		including removal of all 'goto' commands. :-); 
		J. Nardone, Nov. 14, 1994
	V0.4    Renamed variables and constants to 'azt' instead of 'mcd'; had
		to make some "compatibility" defines in azt.h; please note,
		that the source file was renamed to azt.c, the include file to
		azt.h                
		Speeded up drive recognition during init (will be a little bit 
		slower than before if no drive is installed!); suggested by
		Robby Schirmer.
		read_count declared volatile and set to AZT_BUF_SIZ to make
		drive faster (now 300kB/sec, was 60kB/sec before, measured
		by 'time dd if=/dev/cdrom of=/dev/null bs=2048 count=4096';
		different AZT_BUF_SIZes were test, above 16 no further im-
		provement seems to be possible; suggested by E.Moenkeberg.
		W.Zimmermann, Nov. 18, 1994
	V0.42   Included getAztStatus command in GetQChannelInfo() to allow
		reading Q-channel info on audio disks, if drive is stopped, 
		and some other bug fixes in the audio stuff, suggested by 
		Robby Schirmer.
		Added more ioctls (reading data in mode 1 and mode 2).
		Completely removed the old azt_poll() routine.
		Detection of ORCHID CDS-3110 in aztcd_init implemented.
		Additional debugging aids (see the readme file).
		W.Zimmermann, Dec. 9, 1994  
	V0.50   Autodetection of drives implemented.
		W.Zimmermann, Dec. 12, 1994
	V0.52   Prepared for including in the standard kernel, renamed most
		variables to contain 'azt', included autoconf.h
		W.Zimmermann, Dec. 16, 1994        
	V0.6    Version for being included in the standard Linux kernel.
		Renamed source and header file to aztcd.c and aztcd.h
		W.Zimmermann, Dec. 24, 1994
	V0.7    Changed VERIFY_READ to VERIFY_WRITE in aztcd_ioctl, case
		CDROMREADMODE1 and CDROMREADMODE2; bug fix in the ioctl,
		which causes kernel crashes when playing audio, changed 
		include-files (config.h instead of autoconf.h, removed
		delay.h)
		W.Zimmermann, Jan. 8, 1995
	V0.72   Some more modifications for adaption to the standard kernel.
		W.Zimmermann, Jan. 16, 1995
        V0.80   aztcd is now part of the standard kernel since version 1.1.83.
                Modified the SET_TIMER and CLEAR_TIMER macros to comply with
                the new timer scheme.
                W.Zimmermann, Jan. 21, 1995
        V0.90   Included CDROMVOLCTRL, but with my Aztech drive I can only turn
                the channels on and off. If it works better with your drive, 
                please mail me. Also implemented ACMD_CLOSE for CDROMSTART.
                W.Zimmermann, Jan. 24, 1995
        V1.00   Implemented close and lock tray commands. Patches supplied by
		Frank Racis        
                Added support for loadable MODULEs, so aztcd can now also be
                loaded by insmod and removed by rmmod during run time
                Werner Zimmermann, Mar. 24, 95
        V1.10   Implemented soundcard configuration for Orchid CDS-3110 drives
                connected to Soundwave32 cards. Release for LST 2.1.
                (still experimental)
                Werner Zimmermann, May 8, 95
        V1.20   Implemented limited support for DOSEMU0.60's cdrom.c. Now it works, but
                sometimes DOSEMU may hang for 30 seconds or so. A fully functional ver-
                sion needs an update of Dosemu0.60's cdrom.c, which will come with the 
                next revision of Dosemu.
                Also Soundwave32 support now works.
                Werner Zimmermann, May 22, 95
	V1.30   Auto-eject feature. Inspired by Franc Racis ([e-mail])
	        Werner Zimmermann, July 4, 95
	V1.40   Started multisession support. Implementation copied from mcdx.c
	        by Heiko Schlittermann. Not tested yet.
	        Werner Zimmermann, July 15, 95
        V1.50   Implementation of ioctl CDROMRESET, continued multisession, began
                XA, but still untested. Heavy modifications to drive status de-
                tection.
                Werner Zimmermann, July 25, 95
        V1.60   XA support now should work. Speeded up drive recognition in cases, 
                where no drive is installed.
                Werner Zimmermann, August 8, 1995
        V1.70   Multisession support now is completed, but there is still not 
                enough testing done. If you can test it, please contact me. For
                details please read /usr/src/linux/Documentation/cdrom/aztcd
                Werner Zimmermann, August 19, 1995
        V1.80   Modification to suit the new kernel boot procedure introduced
                with kernel 1.3.33. Will definitely not work with older kernels.
                Programming done by Linus himself.
                Werner Zimmermann, October 11, 1995
	V1.90   Support for Conrad TXC drives, thank's to Jochen Kunz and Olaf Kaluza.
	        Werner Zimmermann, October 21, 1995
        V2.00   Changed #include "blk.h" to <linux/blk.h> as the directory
                structure was changed. README.aztcd is now /usr/src/docu-
                mentation/cdrom/aztcd
                Werner Zimmermann, November 10, 95
        V2.10   Started to modify azt_poll to prevent reading beyond end of
                tracks.
                Werner Zimmermann, December 3, 95
        V2.20   Changed some comments
                Werner Zimmermann, April 1, 96
        V2.30   Implemented support for CyCDROM CR520, CR940, Code for CR520 
        	delivered by H.Berger with preworks by E.Moenkeberg.
                Werner Zimmermann, April 29, 96
        V2.40   Reorganized the placement of functions in the source code file
                to reflect the layered approach; did not actually change code
                Werner Zimmermann, May 1, 96
        V2.50   Heiko Eissfeldt suggested to remove some VERIFY_READs in 
                aztcd_ioctl; check_aztcd_media_change modified 
                Werner Zimmermann, May 16, 96       
	V2.60   Implemented Auto-Probing; made changes for kernel's 2.1.xx blocksize
                Adaption to linux kernel > 2.1.0
		Werner Zimmermann, Nov 29, 97
		
        November 1999 -- Make kernel-parameter implementation work with 2.3.x 
	                 Removed init_module & cleanup_module in favor of 
			 module_init & module_exit.
			 Torben Mathiasen <[e-mail]>
*/

#include <linux/version.h>

#define MAJOR_NR AZTECH_CDROM_MAJOR

#include <linux/blk.h>
#include "aztcd.h"

#include <linux/module.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/timer.h>
#include <linux/fs.h>
#include <linux/kernel.h>
#include <linux/cdrom.h>
#include <linux/ioport.h>
#include <linux/string.h>
#include <linux/major.h>
#include <linux/devfs_fs_kernel.h>

#include <linux/init.h>

#include <asm/system.h>
#include <asm/io.h>

#include <asm/uaccess.h>
static int aztcd_blocksizes[1] = { 2048 };


/*###########################################################################
  Defines
  ###########################################################################
*/
#define SET_TIMER(func, jifs)   delay_timer.expires = jiffies + (jifs); \
                                delay_timer.function = (void *) (func); \
                                add_timer(&delay_timer);

#define CLEAR_TIMER             del_timer(&delay_timer);

#define RETURNM(message,value) {printk("aztcd: Warning: %s failed\n",message);\
                                return value;}
#define RETURN(message)        {printk("aztcd: Warning: %s failed\n",message);\
                                return;}

/* Macros to switch the IDE-interface to the slave device and back to the master*/
#define SWITCH_IDE_SLAVE  outb_p(0xa0,azt_port+6); \
	                  outb_p(0x10,azt_port+6); \
	                  outb_p(0x00,azt_port+7); \
	                  outb_p(0x10,azt_port+6);
#define SWITCH_IDE_MASTER outb_p(0xa0,azt_port+6);


#if 0
#define AZT_TEST
#define AZT_TEST1		/* <int-..> */
#define AZT_TEST2		/* do_aztcd_request */
#define AZT_TEST3		/* AZT_S_state */
#define AZT_TEST4		/* QUICK_LOOP-counter */
#define AZT_TEST5		/* port(1) state */
#define AZT_DEBUG
#define AZT_DEBUG_MULTISESSION
#endif

#define CURRENT_VALID \
  (!QUEUE_EMPTY && MAJOR(CURRENT -> rq_dev) == MAJOR_NR && CURRENT -> cmd == READ \
   && CURRENT -> sector != -1)

#define AFL_STATUSorDATA (AFL_STATUS | AFL_DATA)
#define AZT_BUF_SIZ 16

#define READ_TIMEOUT 3000

#define azt_port aztcd		/*needed for the modutils */

/*##########################################################################
  Type Definitions
  ##########################################################################
*/
enum azt_state_e { AZT_S_IDLE,	/* 0 */
	AZT_S_START,		/* 1 */
	AZT_S_MODE,		/* 2 */
	AZT_S_READ,		/* 3 */
	AZT_S_DATA,		/* 4 */
	AZT_S_STOP,		/* 5 */
	AZT_S_STOPPING		/* 6 */
};
enum azt_read_modes { AZT_MODE_0,	/*read mode for audio disks, not supported by Aztech firmware */
	AZT_MODE_1,		/*read mode for normal CD-ROMs */
	AZT_MODE_2		/*read mode for XA CD-ROMs */
};

/*##########################################################################
  Global Variables
  ##########################################################################
*/
static int aztPresent = 0;

static volatile int azt_transfer_is_active = 0;

static char azt_buf[CD_FRAMESIZE_RAW * AZT_BUF_SIZ];	/*buffer for block size conversion */
#if AZT_PRIVATE_IOCTLS
static char buf[CD_FRAMESIZE_RAW];	/*separate buffer for the ioctls */
#endif

static volatile int azt_buf_bn[AZT_BUF_SIZ], azt_next_bn;
static volatile int azt_buf_in, azt_buf_out = -1;
static volatile int azt_error = 0;
static int azt_open_count = 0;
static volatile enum azt_state_e azt_state = AZT_S_IDLE;
#ifdef AZT_TEST3
static volatile enum azt_state_e azt_state_old = AZT_S_STOP;
static volatile int azt_st_old = 0;
#endif
static volatile enum azt_read_modes azt_read_mode = AZT_MODE_1;

static int azt_mode = -1;
static volatile int azt_read_count = 1;

static int azt_port = AZT_BASE_ADDR;

MODULE_PARM(azt_port, "i");

static int azt_port_auto[16] = AZT_BASE_AUTO;

static char azt_cont = 0;
static char azt_init_end = 0;
static char azt_auto_eject = AZT_AUTO_EJECT;

static int AztTimeout, AztTries;
static DECLARE_WAIT_QUEUE_HEAD(azt_waitq);
static struct timer_list delay_timer;

static struct azt_DiskInfo DiskInfo;
static struct azt_Toc Toc[MAX_TRACKS];
static struct azt_Play_msf azt_Play;

static int aztAudioStatus = CDROM_AUDIO_NO_STATUS;
static char aztDiskChanged = 1;
static char aztTocUpToDate = 0;

static unsigned char aztIndatum;
static unsigned long aztTimeOutCount;
static int aztCmd = 0;

/*###########################################################################
   Function Prototypes
  ###########################################################################
*/
/* CDROM Drive Low Level I/O Functions */
void op_ok(void);
void pa_ok(void);
void sten_low(void);
void dten_low(void);
void statusAzt(void);
static void aztStatTimer(void);

/* CDROM Drive Command Functions */
static int aztSendCmd(int cmd);
static int sendAztCmd(int cmd, struct azt_Play_msf *params);
static int aztSeek(struct azt_Play_msf *params);
static int aztSetDiskType(int type);
static int aztStatus(void);
static int getAztStatus(void);
static int aztPlay(struct azt_Play_msf *arg);
static void aztCloseDoor(void);
static void aztLockDoor(void);
static void aztUnlockDoor(void);
static int aztGetValue(unsigned char *result);
static int aztGetQChannelInfo(struct azt_Toc *qp);
static int aztUpdateToc(void);
static int aztGetDiskInfo(void);
#if AZT_MULTISESSION
static int aztGetMultiDiskInfo(void);
#endif
static int aztGetToc(int multi);

/* Kernel Interface Functions */
static int check_aztcd_media_change(kdev_t full_dev);
static int aztcd_ioctl(struct inode *ip, struct file *fp, unsigned int cmd,
		       unsigned long arg);
static void azt_transfer(void);
static void do_aztcd_request(request_queue_t *);
static void azt_invalidate_buffers(void);
int aztcd_open(struct inode *ip, struct file *fp);

static int aztcd_release(struct inode *inode, struct file *file);

int aztcd_init(void);

static struct block_device_operations azt_fops = {
	owner:THIS_MODULE,
	open:aztcd_open,
	release:aztcd_release,
	ioctl:aztcd_ioctl,
	check_media_change:check_aztcd_media_change,
};

/* Aztcd State Machine: Controls Drive Operating State */
static void azt_poll(void);

/* Miscellaneous support functions */
static void azt_hsg2msf(long hsg, struct msf *msf);
static long azt_msf2hsg(struct msf *mp);
static void azt_bin2bcd(unsigned char *p);
static int azt_bcd2bin(unsigned char bcd);

/*##########################################################################
  CDROM Drive Low Level I/O Functions
  ##########################################################################
*/
/* Macros for the drive hardware interface handshake, these macros use
   busy waiting */
/* Wait for OP_OK = drive answers with AFL_OP_OK after receiving a command*/
# define OP_OK op_ok()
void op_ok(void)
{
	aztTimeOutCount = 0;
	do {
		aztIndatum = inb(DATA_PORT);
		aztTimeOutCount++;
		if (aztTimeOutCount >= AZT_TIMEOUT) {
			printk("aztcd: Error Wait OP_OK\n");
			break;
		}
	} while (aztIndatum != AFL_OP_OK);
}

/* Wait for PA_OK = drive answers with AFL_PA_OK after receiving parameters*/
# define PA_OK pa_ok()
void pa_ok(void)
{
	aztTimeOutCount = 0;
	do {
		aztIndatum = inb(DATA_PORT);
		aztTimeOutCount++;
		if (aztTimeOutCount >= AZT_TIMEOUT) {
			printk("aztcd: Error Wait PA_OK\n");
			break;
		}
	} while (aztIndatum != AFL_PA_OK);
}

/* Wait for STEN=Low = handshake signal 'AFL_.._OK available or command executed*/
# define STEN_LOW  sten_low()
void sten_low(void)
{
	aztTimeOutCount = 0;
	do {
		aztIndatum = inb(STATUS_PORT);
		aztTimeOutCount++;
		if (aztTimeOutCount >= AZT_TIMEOUT) {
			if (azt_init_end)
				printk
				    ("aztcd: Error Wait STEN_LOW commands:%x\n",
				     aztCmd);
			break;
		}
	} while (aztIndatum & AFL_STATUS);
}

/* Wait for DTEN=Low = handshake signal 'Data available'*/
# define DTEN_LOW dten_low()
void dten_low(void)
{
	aztTimeOutCount = 0;
	do {
		aztIndatum = inb(STATUS_PORT);
		aztTimeOutCount++;
		if (aztTimeOutCount >= AZT_TIMEOUT) {
			printk("aztcd: Error Wait DTEN_OK\n");
			break;
		}
	} while (aztIndatum & AFL_DATA);
}

/* 
 * Macro for timer wait on STEN=Low, should only be used for 'slow' commands;
 * may cause kernel panic when used in the wrong place
*/
#define STEN_LOW_WAIT   statusAzt()
void statusAzt(void)
{
	AztTimeout = AZT_STATUS_DELAY;
	SET_TIMER(aztStatTimer, HZ / 100);
	sleep_on(&azt_waitq);
	if (AztTimeout <= 0)
		printk("aztcd: Error Wait STEN_LOW_WAIT command:%x\n",
		       aztCmd);
	return;