optcd.c

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/*	linux/drivers/cdrom/optcd.c - Optics Storage 8000 AT CDROM driver
	$Id: optcd.c,v 1.11 1997/01/26 07:13:00 davem Exp $

	Copyright (C) 1995 Leo Spiekman ([e-mail])


	Based on Aztech CD268 CDROM driver by Werner Zimmermann and preworks
	by Eberhard Moenkeberg ([e-mail]). 

	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.
*/

/*	Revision history


	14-5-95		v0.0	Plays sound tracks. No reading of data CDs yet.
				Detection of disk change doesn't work.
	21-5-95		v0.1	First ALPHA version. CD can be mounted. The
				device major nr is borrowed from the Aztech
				driver. Speed is around 240 kb/s, as measured
				with "time dd if=/dev/cdrom of=/dev/null \
				bs=2048 count=4096".
	24-6-95		v0.2	Reworked the #defines for the command codes
				and the like, as well as the structure of
				the hardware communication protocol, to
				reflect the "official" documentation, kindly
				supplied by C.K. Tan, Optics Storage Pte. Ltd.
				Also tidied up the state machine somewhat.
	28-6-95		v0.3	Removed the ISP-16 interface code, as this
				should go into its own driver. The driver now
				has its own major nr.
				Disk change detection now seems to work, too.
				This version became part of the standard
				kernel as of version 1.3.7
	24-9-95		v0.4	Re-inserted ISP-16 interface code which I
				copied from sjcd.c, with a few changes.
				Updated README.optcd. Submitted for
				inclusion in 1.3.21
	29-9-95		v0.4a	Fixed bug that prevented compilation as module
	25-10-95	v0.5	Started multisession code. Implementation
				copied from Werner Zimmermann, who copied it
				from Heiko Schlittermann's mcdx.
	17-1-96		v0.6	Multisession works; some cleanup too.
	18-4-96		v0.7	Increased some timing constants;
				thanks to Luke McFarlane. Also tidied up some
				printk behaviour. ISP16 initialization
				is now handled by a separate driver.
				
	09-11-99 	  	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]>
*/

/* Includes */


#include <linux/module.h>
#include <linux/mm.h>
#include <linux/ioport.h>
#include <linux/init.h>
#include <linux/devfs_fs_kernel.h>

#include <asm/io.h>

#define MAJOR_NR OPTICS_CDROM_MAJOR
#include <linux/blk.h>

#include <linux/cdrom.h>
#include "optcd.h"

#include <asm/uaccess.h>


/* Debug support */


/* Don't forget to add new debug flags here. */
#if DEBUG_DRIVE_IF | DEBUG_VFS | DEBUG_CONV | DEBUG_TOC | \
    DEBUG_BUFFERS | DEBUG_REQUEST | DEBUG_STATE | DEBUG_MULTIS
#define DEBUG(x) debug x
static void debug(int debug_this, const char* fmt, ...)
{
	char s[1024];
	va_list args;

	if (!debug_this)
		return;

	va_start(args, fmt);
	vsprintf(s, fmt, args);
	printk(KERN_DEBUG "optcd: %s\n", s);
	va_end(args);
}
#else
#define DEBUG(x)
#endif

static int blksize = 2048;
static int hsecsize = 2048;


/* Drive hardware/firmware characteristics
   Identifiers in accordance with Optics Storage documentation */


#define optcd_port optcd			/* Needed for the modutils. */
static short optcd_port = OPTCD_PORTBASE;	/* I/O base of drive. */
MODULE_PARM(optcd_port, "h");
/* Drive registers, read */
#define DATA_PORT	optcd_port	/* Read data/status */
#define STATUS_PORT	optcd_port+1	/* Indicate data/status availability */

/* Drive registers, write */
#define COMIN_PORT	optcd_port	/* For passing command/parameter */
#define RESET_PORT	optcd_port+1	/* Write anything and wait 0.5 sec */
#define HCON_PORT	optcd_port+2	/* Host Xfer Configuration */


/* Command completion/status read from DATA register */
#define ST_DRVERR		0x80
#define ST_DOOR_OPEN		0x40
#define ST_MIXEDMODE_DISK	0x20
#define ST_MODE_BITS		0x1c
#define ST_M_STOP		0x00
#define ST_M_READ		0x04
#define ST_M_AUDIO		0x04
#define ST_M_PAUSE		0x08
#define ST_M_INITIAL		0x0c
#define ST_M_ERROR		0x10
#define ST_M_OTHERS		0x14
#define	ST_MODE2TRACK		0x02
#define	ST_DSK_CHG		0x01
#define ST_L_LOCK		0x01
#define ST_CMD_OK		0x00
#define ST_OP_OK		0x01
#define ST_PA_OK		0x02
#define ST_OP_ERROR		0x05
#define ST_PA_ERROR		0x06


/* Error codes (appear as command completion code from DATA register) */
/* Player related errors */
#define ERR_ILLCMD	0x11	/* Illegal command to player module */
#define ERR_ILLPARM	0x12	/* Illegal parameter to player module */
#define ERR_SLEDGE	0x13
#define ERR_FOCUS	0x14
#define ERR_MOTOR	0x15
#define ERR_RADIAL	0x16
#define ERR_PLL		0x17	/* PLL lock error */
#define ERR_SUB_TIM	0x18	/* Subcode timeout error */
#define ERR_SUB_NF	0x19	/* Subcode not found error */
#define ERR_TRAY	0x1a
#define ERR_TOC		0x1b	/* Table of Contents read error */
#define ERR_JUMP	0x1c
/* Data errors */
#define ERR_MODE	0x21
#define ERR_FORM	0x22
#define ERR_HEADADDR	0x23	/* Header Address not found */
#define ERR_CRC		0x24
#define ERR_ECC		0x25	/* Uncorrectable ECC error */
#define ERR_CRC_UNC	0x26	/* CRC error and uncorrectable error */
#define ERR_ILLBSYNC	0x27	/* Illegal block sync error */
#define ERR_VDST	0x28	/* VDST not found */
/* Timeout errors */
#define ERR_READ_TIM	0x31	/* Read timeout error */
#define ERR_DEC_STP	0x32	/* Decoder stopped */
#define ERR_DEC_TIM	0x33	/* Decoder interrupt timeout error */
/* Function abort codes */
#define ERR_KEY		0x41	/* Key -Detected abort */
#define ERR_READ_FINISH	0x42	/* Read Finish */
/* Second Byte diagnostic codes */
#define ERR_NOBSYNC	0x01	/* No block sync */
#define ERR_SHORTB	0x02	/* Short block */
#define ERR_LONGB	0x03	/* Long block */
#define ERR_SHORTDSP	0x04	/* Short DSP word */
#define ERR_LONGDSP	0x05	/* Long DSP word */


/* Status availability flags read from STATUS register */
#define FL_EJECT	0x20
#define FL_WAIT		0x10	/* active low */
#define FL_EOP		0x08	/* active low */
#define FL_STEN		0x04	/* Status available when low */
#define FL_DTEN		0x02	/* Data available when low */
#define FL_DRQ		0x01	/* active low */
#define FL_RESET	0xde	/* These bits are high after a reset */
#define FL_STDT		(FL_STEN|FL_DTEN)


/* Transfer mode, written to HCON register */
#define HCON_DTS	0x08
#define HCON_SDRQB	0x04
#define HCON_LOHI	0x02
#define HCON_DMA16	0x01


/* Drive command set, written to COMIN register */
/* Quick response commands */
#define COMDRVST	0x20	/* Drive Status Read */
#define COMERRST	0x21	/* Error Status Read */
#define COMIOCTLISTAT	0x22	/* Status Read; reset disk changed bit */
#define COMINITSINGLE	0x28	/* Initialize Single Speed */
#define COMINITDOUBLE	0x29	/* Initialize Double Speed */
#define COMUNLOCK	0x30	/* Unlock */
#define COMLOCK		0x31	/* Lock */
#define COMLOCKST	0x32	/* Lock/Unlock Status */
#define COMVERSION	0x40	/* Get Firmware Revision */
#define COMVOIDREADMODE	0x50	/* Void Data Read Mode */
/* Read commands */
#define COMFETCH	0x60	/* Prefetch Data */
#define COMREAD		0x61	/* Read */
#define COMREADRAW	0x62	/* Read Raw Data */
#define COMREADALL	0x63	/* Read All 2646 Bytes */
/* Player control commands */
#define COMLEADIN	0x70	/* Seek To Lead-in */
#define COMSEEK		0x71	/* Seek */
#define COMPAUSEON	0x80	/* Pause On */
#define COMPAUSEOFF	0x81	/* Pause Off */
#define COMSTOP		0x82	/* Stop */
#define COMOPEN		0x90	/* Open Tray Door */
#define COMCLOSE	0x91	/* Close Tray Door */
#define COMPLAY		0xa0	/* Audio Play */
#define COMPLAY_TNO	0xa2	/* Audio Play By Track Number */
#define COMSUBQ		0xb0	/* Read Sub-q Code */
#define COMLOCATION	0xb1	/* Read Head Position */
/* Audio control commands */
#define COMCHCTRL	0xc0	/* Audio Channel Control */
/* Miscellaneous (test) commands */
#define COMDRVTEST	0xd0	/* Write Test Bytes */
#define COMTEST		0xd1	/* Diagnostic Test */

/* Low level drive interface. Only here we do actual I/O
   Waiting for status / data available */


/* Busy wait until FLAG goes low. Return 0 on timeout. */
inline static int flag_low(int flag, unsigned long timeout)
{
	int flag_high;
	unsigned long count = 0;

	while ((flag_high = (inb(STATUS_PORT) & flag)))
		if (++count >= timeout)
			break;

	DEBUG((DEBUG_DRIVE_IF, "flag_low 0x%x count %ld%s",
		flag, count, flag_high ? " timeout" : ""));
	return !flag_high;
}


/* Timed waiting for status or data */
static int sleep_timeout;	/* max # of ticks to sleep */
static DECLARE_WAIT_QUEUE_HEAD(waitq);
static void sleep_timer(unsigned long data);
static struct timer_list delay_timer = {function: sleep_timer};


/* Timer routine: wake up when desired flag goes low,
   or when timeout expires. */
static void sleep_timer(unsigned long data)
{
	int flags = inb(STATUS_PORT) & FL_STDT;

	if (flags == FL_STDT && --sleep_timeout > 0) {
		mod_timer(&delay_timer, jiffies + HZ/100); /* multi-statement macro */
	} else
		wake_up(&waitq);
}


/* Sleep until FLAG goes low. Return 0 on timeout or wrong flag low. */
static int sleep_flag_low(int flag, unsigned long timeout)
{
	int flag_high;

	DEBUG((DEBUG_DRIVE_IF, "sleep_flag_low"));

	sleep_timeout = timeout;
	flag_high = inb(STATUS_PORT) & flag;
	if (flag_high && sleep_timeout > 0) {
		mod_timer(&delay_timer, jiffies + HZ/100);
		sleep_on(&waitq);
		flag_high = inb(STATUS_PORT) & flag;
	}

	DEBUG((DEBUG_DRIVE_IF, "flag 0x%x count %ld%s",
		flag, timeout, flag_high ? " timeout" : ""));
	return !flag_high;
}

/* Low level drive interface. Only here we do actual I/O
   Sending commands and parameters */


/* Errors in the command protocol */
#define ERR_IF_CMD_TIMEOUT	0x100
#define ERR_IF_ERR_TIMEOUT	0x101
#define ERR_IF_RESP_TIMEOUT	0x102
#define ERR_IF_DATA_TIMEOUT	0x103
#define ERR_IF_NOSTAT		0x104


/* Send command code. Return <0 indicates error */
static int send_cmd(int cmd)
{
	unsigned char ack;

	DEBUG((DEBUG_DRIVE_IF, "sending command 0x%02x\n", cmd));

	outb(HCON_DTS, HCON_PORT);	/* Enable Suspend Data Transfer */
	outb(cmd, COMIN_PORT);		/* Send command code */
	if (!flag_low(FL_STEN, BUSY_TIMEOUT))	/* Wait for status */
		return -ERR_IF_CMD_TIMEOUT;
	ack = inb(DATA_PORT);		/* read command acknowledge */
	outb(HCON_SDRQB, HCON_PORT);	/* Disable Suspend Data Transfer */
	return ack==ST_OP_OK ? 0 : -ack;
}


/* Send command parameters. Return <0 indicates error */
static int send_params(struct cdrom_msf *params)
{
	unsigned char ack;

	DEBUG((DEBUG_DRIVE_IF, "sending parameters"
		" %02x:%02x:%02x"
		" %02x:%02x:%02x",
		params->cdmsf_min0,
		params->cdmsf_sec0,
		params->cdmsf_frame0,
		params->cdmsf_min1,
		params->cdmsf_sec1,
		params->cdmsf_frame1));

	outb(params->cdmsf_min0, COMIN_PORT);
	outb(params->cdmsf_sec0, COMIN_PORT);
	outb(params->cdmsf_frame0, COMIN_PORT);
	outb(params->cdmsf_min1, COMIN_PORT);
	outb(params->cdmsf_sec1, COMIN_PORT);
	outb(params->cdmsf_frame1, COMIN_PORT);
	if (!flag_low(FL_STEN, BUSY_TIMEOUT))	/* Wait for status */
		return -ERR_IF_CMD_TIMEOUT;
	ack = inb(DATA_PORT);		/* read command acknowledge */
	return ack==ST_PA_OK ? 0 : -ack;
}


/* Send parameters for SEEK command. Return <0 indicates error */
static int send_seek_params(struct cdrom_msf *params)
{
	unsigned char ack;

	DEBUG((DEBUG_DRIVE_IF, "sending seek parameters"
		" %02x:%02x:%02x",
		params->cdmsf_min0,
		params->cdmsf_sec0,
		params->cdmsf_frame0));

	outb(params->cdmsf_min0, COMIN_PORT);
	outb(params->cdmsf_sec0, COMIN_PORT);
	outb(params->cdmsf_frame0, COMIN_PORT);
	if (!flag_low(FL_STEN, BUSY_TIMEOUT))	/* Wait for status */
		return -ERR_IF_CMD_TIMEOUT;
	ack = inb(DATA_PORT);		/* read command acknowledge */
	return ack==ST_PA_OK ? 0 : -ack;
}


/* Wait for command execution status. Choice between busy waiting
   and sleeping. Return value <0 indicates timeout. */
inline static int get_exec_status(int busy_waiting)
{
	unsigned char exec_status;

	if (busy_waiting
	    ? !flag_low(FL_STEN, BUSY_TIMEOUT)
	    : !sleep_flag_low(FL_STEN, SLEEP_TIMEOUT))
		return -ERR_IF_CMD_TIMEOUT;

	exec_status = inb(DATA_PORT);
	DEBUG((DEBUG_DRIVE_IF, "returned exec status 0x%02x", exec_status));
	return exec_status;
}


/* Wait busy for extra byte of data that a command returns.
   Return value <0 indicates timeout. */
inline static int get_data(int short_timeout)
{
	unsigned char data;

	if (!flag_low(FL_STEN, short_timeout ? FAST_TIMEOUT : BUSY_TIMEOUT))
		return -ERR_IF_DATA_TIMEOUT;

	data = inb(DATA_PORT);
	DEBUG((DEBUG_DRIVE_IF, "returned data 0x%02x", data));
	return data;
}


/* Returns 0 if failed */
static int reset_drive(void)
{
	unsigned long count = 0;
	int flags;

	DEBUG((DEBUG_DRIVE_IF, "reset drive"));

	outb(0, RESET_PORT);
	while (++count < RESET_WAIT)
		inb(DATA_PORT);

	count = 0;
	while ((flags = (inb(STATUS_PORT) & FL_RESET)) != FL_RESET)
		if (++count >= BUSY_TIMEOUT)
			break;

	DEBUG((DEBUG_DRIVE_IF, "reset %s",
		flags == FL_RESET ? "succeeded" : "failed"));

	if (flags != FL_RESET)
		return 0;		/* Reset failed */
	outb(HCON_SDRQB, HCON_PORT);	/* Disable Suspend Data Transfer */
	return 1;			/* Reset succeeded */
}


/* Facilities for asynchronous operation */

/* Read status/data availability flags FL_STEN and FL_DTEN */
inline static int stdt_flags(void)
{
	return inb(STATUS_PORT) & FL_STDT;
}


/* Fetch status that has previously been waited for. <0 means not available */
inline static int fetch_status(void)
{
	unsigned char status;

	if (inb(STATUS_PORT) & FL_STEN)
		return -ERR_IF_NOSTAT;

	status = inb(DATA_PORT);
	DEBUG((DEBUG_DRIVE_IF, "fetched exec status 0x%02x", status));
	return status;
}


/* Fetch data that has previously been waited for. */
inline static void fetch_data(char *buf, int n)
{
	insb(DATA_PORT, buf, n);
	DEBUG((DEBUG_DRIVE_IF, "fetched 0x%x bytes", n));
}


/* Flush status and data fifos */
inline static void flush_data(void)
{
	while ((inb(STATUS_PORT) & FL_STDT) != FL_STDT)
		inb(DATA_PORT);
	DEBUG((DEBUG_DRIVE_IF, "flushed fifos"));
}

/* Command protocol */


/* Send a simple command and wait for response. Command codes < COMFETCH
   are quick response commands */
inline static int exec_cmd(int cmd)
{
	int ack = send_cmd(cmd);
	if (ack < 0)
		return ack;
	return get_exec_status(cmd < COMFETCH);
}


/* Send a command with parameters. Don't wait for the response,
 * which consists of data blocks read from the CD. */
inline static int exec_read_cmd(int cmd, struct cdrom_msf *params)
{
	int ack = send_cmd(cmd);
	if (ack < 0)
		return ack;
	return send_params(params);
}


/* Send a seek command with parameters and wait for response */
inline static int exec_seek_cmd(int cmd, struct cdrom_msf *params)
{
	int ack = send_cmd(cmd);
	if (ack < 0)
		return ack;
	ack = send_seek_params(params);
	if (ack < 0)
		return ack;
	return 0;
}


/* Send a command with parameters and wait for response */
inline static int exec_long_cmd(int cmd, struct cdrom_msf *params)
{
	int ack = exec_read_cmd(cmd, params);
	if (ack < 0)
		return ack;
	return get_exec_status(0);