ide-floppy.c

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		unsigned reserved3	:1;	/* Reserved */
		unsigned drv		:1;	/* The responding drive will be drive 0 (0) or drive 1 (1) */
		unsigned one5		:1;	/* Should be set to 1 */
		unsigned reserved6	:1;	/* Reserved */
		unsigned one7		:1;	/* Should be set to 1 */
#elif defined(__BIG_ENDIAN_BITFIELD)
		unsigned one7		:1;	/* Should be set to 1 */
		unsigned reserved6	:1;	/* Reserved */
		unsigned one5		:1;	/* Should be set to 1 */
		unsigned drv		:1;	/* The responding drive will be drive 0 (0) or drive 1 (1) */
		unsigned reserved3	:1;	/* Reserved */
		unsigned sam_lun	:3;	/* Logical unit number */
#else
#error "Bitfield endianness not defined! Check your byteorder.h"
#endif
	} b;
} idefloppy_drivesel_reg_t;

/*
 *	ATAPI Device Control Register
 */
typedef union {			
	unsigned all			:8;
	struct {
#if defined(__LITTLE_ENDIAN_BITFIELD)
		unsigned zero0		:1;	/* Should be set to zero */
		unsigned nien		:1;	/* Device interrupt is disabled (1) or enabled (0) */
		unsigned srst		:1;	/* ATA software reset. ATAPI devices should use the new ATAPI srst. */
		unsigned one3		:1;	/* Should be set to 1 */
		unsigned reserved4567	:4;	/* Reserved */
#elif defined(__BIG_ENDIAN_BITFIELD)
		unsigned reserved4567	:4;	/* Reserved */
		unsigned one3		:1;	/* Should be set to 1 */
		unsigned srst		:1;	/* ATA software reset. ATAPI devices should use the new ATAPI srst. */
		unsigned nien		:1;	/* Device interrupt is disabled (1) or enabled (0) */
		unsigned zero0		:1;	/* Should be set to zero */
#else
#error "Bitfield endianness not defined! Check your byteorder.h"
#endif
	} b;
} idefloppy_control_reg_t;

/*
 *	The following is used to format the general configuration word of
 *	the ATAPI IDENTIFY DEVICE command.
 */
struct idefloppy_id_gcw {	
#if defined(__LITTLE_ENDIAN_BITFIELD)
	unsigned packet_size		:2;	/* Packet Size */
	unsigned reserved234		:3;	/* Reserved */
	unsigned drq_type		:2;	/* Command packet DRQ type */
	unsigned removable		:1;	/* Removable media */
	unsigned device_type		:5;	/* Device type */
	unsigned reserved13		:1;	/* Reserved */
	unsigned protocol		:2;	/* Protocol type */
#elif defined(__BIG_ENDIAN_BITFIELD)
	unsigned protocol		:2;	/* Protocol type */
	unsigned reserved13		:1;	/* Reserved */
	unsigned device_type		:5;	/* Device type */
	unsigned removable		:1;	/* Removable media */
	unsigned drq_type		:2;	/* Command packet DRQ type */
	unsigned reserved234		:3;	/* Reserved */
	unsigned packet_size		:2;	/* Packet Size */
#else
#error "Bitfield endianness not defined! Check your byteorder.h"
#endif
};

/*
 *	INQUIRY packet command - Data Format
 */
typedef struct {
#if defined(__LITTLE_ENDIAN_BITFIELD)
	unsigned	device_type	:5;	/* Peripheral Device Type */
	unsigned	reserved0_765	:3;	/* Peripheral Qualifier - Reserved */
	unsigned	reserved1_6t0	:7;	/* Reserved */
	unsigned	rmb		:1;	/* Removable Medium Bit */
	unsigned	ansi_version	:3;	/* ANSI Version */
	unsigned	ecma_version	:3;	/* ECMA Version */
	unsigned	iso_version	:2;	/* ISO Version */
	unsigned	response_format :4;	/* Response Data Format */
	unsigned	reserved3_45	:2;	/* Reserved */
	unsigned	reserved3_6	:1;	/* TrmIOP - Reserved */
	unsigned	reserved3_7	:1;	/* AENC - Reserved */
#elif defined(__BIG_ENDIAN_BITFIELD)
	unsigned	reserved0_765	:3;	/* Peripheral Qualifier - Reserved */
	unsigned	device_type	:5;	/* Peripheral Device Type */
	unsigned	rmb		:1;	/* Removable Medium Bit */
	unsigned	reserved1_6t0	:7;	/* Reserved */
	unsigned	iso_version	:2;	/* ISO Version */
	unsigned	ecma_version	:3;	/* ECMA Version */
	unsigned	ansi_version	:3;	/* ANSI Version */
	unsigned	reserved3_7	:1;	/* AENC - Reserved */
	unsigned	reserved3_6	:1;	/* TrmIOP - Reserved */
	unsigned	reserved3_45	:2;	/* Reserved */
	unsigned	response_format :4;	/* Response Data Format */
#else
#error "Bitfield endianness not defined! Check your byteorder.h"
#endif
	u8		additional_length;	/* Additional Length (total_length-4) */
	u8		rsv5, rsv6, rsv7;	/* Reserved */
	u8		vendor_id[8];		/* Vendor Identification */
	u8		product_id[16];		/* Product Identification */
	u8		revision_level[4];	/* Revision Level */
	u8		vendor_specific[20];	/* Vendor Specific - Optional */
	u8		reserved56t95[40];	/* Reserved - Optional */
						/* Additional information may be returned */
} idefloppy_inquiry_result_t;

/*
 *	REQUEST SENSE packet command result - Data Format.
 */
typedef struct {
#if defined(__LITTLE_ENDIAN_BITFIELD)
	unsigned	error_code	:7;	/* Current error (0x70) */
	unsigned	valid		:1;	/* The information field conforms to SFF-8070i */
	u8		reserved1	:8;	/* Reserved */
	unsigned	sense_key	:4;	/* Sense Key */
	unsigned	reserved2_4	:1;	/* Reserved */
	unsigned	ili		:1;	/* Incorrect Length Indicator */
	unsigned	reserved2_67	:2;
#elif defined(__BIG_ENDIAN_BITFIELD)
	unsigned	valid		:1;	/* The information field conforms to SFF-8070i */
	unsigned	error_code	:7;	/* Current error (0x70) */
	u8		reserved1	:8;	/* Reserved */
	unsigned	reserved2_67	:2;
	unsigned	ili		:1;	/* Incorrect Length Indicator */
	unsigned	reserved2_4	:1;	/* Reserved */
	unsigned	sense_key	:4;	/* Sense Key */
#else
#error "Bitfield endianness not defined! Check your byteorder.h"
#endif
	u32		information __attribute__ ((packed));
	u8		asl;			/* Additional sense length (n-7) */
	u32		command_specific;	/* Additional command specific information */
	u8		asc;			/* Additional Sense Code */
	u8		ascq;			/* Additional Sense Code Qualifier */
	u8		replaceable_unit_code;	/* Field Replaceable Unit Code */
	u8		reserved[3];
	u8		pad[2];			/* Padding to 20 bytes */
} idefloppy_request_sense_result_t;

/*
 *	Pages of the SELECT SENSE / MODE SENSE packet commands.
 */
#define	IDEFLOPPY_CAPABILITIES_PAGE	0x1b
#define IDEFLOPPY_FLEXIBLE_DISK_PAGE	0x05

/*
 *	Mode Parameter Header for the MODE SENSE packet command
 */
typedef struct {
	u16		mode_data_length;	/* Length of the following data transfer */
	u8		medium_type;		/* Medium Type */
#if defined(__LITTLE_ENDIAN_BITFIELD)
	unsigned	reserved3	:7;
	unsigned	wp		:1;	/* Write protect */
#elif defined(__BIG_ENDIAN_BITFIELD)
	unsigned	wp		:1;	/* Write protect */
	unsigned	reserved3	:7;
#else
#error "Bitfield endianness not defined! Check your byteorder.h"
#endif
	u8		reserved[4];
} idefloppy_mode_parameter_header_t;

#define IDEFLOPPY_MIN(a,b)	((a)<(b) ? (a):(b))
#define	IDEFLOPPY_MAX(a,b)	((a)>(b) ? (a):(b))

/*
 *	Too bad. The drive wants to send us data which we are not ready to accept.
 *	Just throw it away.
 */
static void idefloppy_discard_data (ide_drive_t *drive, unsigned int bcount)
{
	while (bcount--)
		IN_BYTE (IDE_DATA_REG);
}

#if IDEFLOPPY_DEBUG_BUGS
static void idefloppy_write_zeros (ide_drive_t *drive, unsigned int bcount)
{
	while (bcount--)
		OUT_BYTE (0, IDE_DATA_REG);
}
#endif /* IDEFLOPPY_DEBUG_BUGS */

/*
 *	idefloppy_end_request is used to finish servicing a request.
 *
 *	For read/write requests, we will call ide_end_request to pass to the
 *	next buffer.
 */
static void idefloppy_end_request (byte uptodate, ide_hwgroup_t *hwgroup)
{
	ide_drive_t *drive = hwgroup->drive;
	idefloppy_floppy_t *floppy = drive->driver_data;
	struct request *rq = hwgroup->rq;
	int error;

#if IDEFLOPPY_DEBUG_LOG
	printk (KERN_INFO "Reached idefloppy_end_request\n");
#endif /* IDEFLOPPY_DEBUG_LOG */

	switch (uptodate) {
		case 0: error = IDEFLOPPY_ERROR_GENERAL; break;
		case 1: error = 0; break;
		default: error = uptodate;
	}
	if (error)
		floppy->failed_pc = NULL;
	/* Why does this happen? */
	if (!rq)
		return;
	if (!IDEFLOPPY_RQ_CMD (rq->cmd)) {
		ide_end_request (uptodate, hwgroup);
		return;
	}
	rq->errors = error;
	ide_end_drive_cmd (drive, 0, 0);
}

static void idefloppy_input_buffers (ide_drive_t *drive, idefloppy_pc_t *pc, unsigned int bcount)
{
	struct request *rq = pc->rq;
	struct buffer_head *bh = rq->bh;
	int count;

	while (bcount) {
		if (pc->b_count == bh->b_size) {
			rq->sector += rq->current_nr_sectors;
			rq->nr_sectors -= rq->current_nr_sectors;
			idefloppy_end_request (1, HWGROUP(drive));
			if ((bh = rq->bh) != NULL)
				pc->b_count = 0;
		}
		if (bh == NULL) {
			printk (KERN_ERR "%s: bh == NULL in idefloppy_input_buffers, bcount == %d\n", drive->name, bcount);
			idefloppy_discard_data (drive, bcount);
			return;
		}
		count = IDEFLOPPY_MIN (bh->b_size - pc->b_count, bcount);
		atapi_input_bytes (drive, bh->b_data + pc->b_count, count);
		bcount -= count; pc->b_count += count;
	}
}

static void idefloppy_output_buffers (ide_drive_t *drive, idefloppy_pc_t *pc, unsigned int bcount)
{
	struct request *rq = pc->rq;
	struct buffer_head *bh = rq->bh;
	int count;
	
	while (bcount) {
		if (!pc->b_count) {
			rq->sector += rq->current_nr_sectors;
			rq->nr_sectors -= rq->current_nr_sectors;
			idefloppy_end_request (1, HWGROUP(drive));
			if ((bh = rq->bh) != NULL) {
				pc->b_data = bh->b_data;
				pc->b_count = bh->b_size;
			}
		}
		if (bh == NULL) {
			printk (KERN_ERR "%s: bh == NULL in idefloppy_output_buffers, bcount == %d\n", drive->name, bcount);
			idefloppy_write_zeros (drive, bcount);
			return;
		}
		count = IDEFLOPPY_MIN (pc->b_count, bcount);
		atapi_output_bytes (drive, pc->b_data, count);
		bcount -= count; pc->b_data += count; pc->b_count -= count;
	}
}

#ifdef CONFIG_BLK_DEV_IDEDMA
static void idefloppy_update_buffers (ide_drive_t *drive, idefloppy_pc_t *pc)
{
	struct request *rq = pc->rq;
	struct buffer_head *bh = rq->bh;

	while ((bh = rq->bh) != NULL)
		idefloppy_end_request (1, HWGROUP(drive));
}
#endif /* CONFIG_BLK_DEV_IDEDMA */

/*
 *	idefloppy_queue_pc_head generates a new packet command request in front
 *	of the request queue, before the current request, so that it will be
 *	processed immediately, on the next pass through the driver.
 */
static void idefloppy_queue_pc_head (ide_drive_t *drive,idefloppy_pc_t *pc,struct request *rq)
{
	ide_init_drive_cmd (rq);
	rq->buffer = (char *) pc;
	rq->cmd = IDEFLOPPY_PC_RQ;
	(void) ide_do_drive_cmd (drive, rq, ide_preempt);
}

static idefloppy_pc_t *idefloppy_next_pc_storage (ide_drive_t *drive)
{
	idefloppy_floppy_t *floppy = drive->driver_data;

	if (floppy->pc_stack_index==IDEFLOPPY_PC_STACK)
		floppy->pc_stack_index=0;
	return (&floppy->pc_stack[floppy->pc_stack_index++]);
}

static struct request *idefloppy_next_rq_storage (ide_drive_t *drive)
{
	idefloppy_floppy_t *floppy = drive->driver_data;

	if (floppy->rq_stack_index==IDEFLOPPY_PC_STACK)
		floppy->rq_stack_index=0;
	return (&floppy->rq_stack[floppy->rq_stack_index++]);
}

/*
 *	idefloppy_analyze_error is called on each failed packet command retry
 *	to analyze the request sense.
 */
static void idefloppy_analyze_error (ide_drive_t *drive,idefloppy_request_sense_result_t *result)
{
	idefloppy_floppy_t *floppy = drive->driver_data;

	floppy->sense_key = result->sense_key; floppy->asc = result->asc; floppy->ascq = result->ascq;
#if IDEFLOPPY_DEBUG_LOG
	if (floppy->failed_pc)
		printk (KERN_INFO "ide-floppy: pc = %x, sense key = %x, asc = %x, ascq = %x\n",floppy->failed_pc->c[0],result->sense_key,result->asc,result->ascq);
	else
		printk (KERN_INFO "ide-floppy: sense key = %x, asc = %x, ascq = %x\n",result->sense_key,result->asc,result->ascq);
#endif /* IDEFLOPPY_DEBUG_LOG */
}

static void idefloppy_request_sense_callback (ide_drive_t *drive)
{
	idefloppy_floppy_t *floppy = drive->driver_data;

#if IDEFLOPPY_DEBUG_LOG
	printk (KERN_INFO "ide-floppy: Reached idefloppy_request_sense_callback\n");
#endif /* IDEFLOPPY_DEBUG_LOG */
	if (!floppy->pc->error) {
		idefloppy_analyze_error (drive,(idefloppy_request_sense_result_t *) floppy->pc->buffer);
		idefloppy_end_request (1,HWGROUP (drive));
	} else {
		printk (KERN_ERR "Error in REQUEST SENSE itself - Aborting request!\n");
		idefloppy_end_request (0,HWGROUP (drive));
	}
}

/*
 *	General packet command callback function.
 */
static void idefloppy_pc_callback (ide_drive_t *drive)
{
	idefloppy_floppy_t *floppy = drive->driver_data;
	
#if IDEFLOPPY_DEBUG_LOG
	printk (KERN_INFO "ide-floppy: Reached idefloppy_pc_callback\n");
#endif /* IDEFLOPPY_DEBUG_LOG */

	idefloppy_end_request (floppy->pc->error ? 0:1, HWGROUP(drive));
}

/*
 *	idefloppy_init_pc initializes a packet command.
 */
static void idefloppy_init_pc (idefloppy_pc_t *pc)
{
	memset (pc->c, 0, 12);
	pc->retries = 0;
	pc->flags = 0;
	pc->request_transfer = 0;
	pc->buffer = pc->pc_buffer;
	pc->buffer_size = IDEFLOPPY_PC_BUFFER_SIZE;
	pc->b_data = NULL;
	pc->callback = &idefloppy_pc_callback;
}

static void idefloppy_create_request_sense_cmd (idefloppy_pc_t *pc)
{
	idefloppy_init_pc (pc);	
	pc->c[0] = IDEFLOPPY_REQUEST_SENSE_CMD;
	pc->c[4] = 255;
	pc->request_transfer = 18;
	pc->callback = &idefloppy_request_sense_callback;
}

/*
 *	idefloppy_retry_pc is called when an error was detected during the
 *	last packet command. We queue a request sense packet command in
 *	the head of the request list.
 */
static void idefloppy_retry_pc (ide_drive_t *drive)
{
	idefloppy_pc_t *pc;
	struct request *rq;
	idefloppy_error_reg_t error;

	error.all = IN_BYTE (IDE_ERROR_REG);
	pc = idefloppy_next_pc_storage (drive);
	rq = idefloppy_next_rq_storage (drive);
	idefloppy_create_request_sense_cmd (pc);
	idefloppy_queue_pc_head (drive, pc, rq);
}

/*
 *	idefloppy_pc_intr is the usual interrupt handler which will be called
 *	during a packet command.
 */
static ide_startstop_t idefloppy_pc_intr (ide_drive_t *drive)
{
	idefloppy_floppy_t *floppy = drive->driver_data;
	idefloppy_status_reg_t status;
	idefloppy_bcount_reg_t bcount;
	idefloppy_ireason_reg_t ireason;
	idefloppy_pc_t *pc=floppy->pc;
	struct request *rq = pc->rq;
	unsigned int temp;

#if IDEFLOPPY_DEBUG_LOG
	printk (KERN_INFO "ide-floppy: Reached idefloppy_pc_intr interrupt handler\n");
#endif /* IDEFLOPPY_DEBUG_LOG */