Release 4.11 drivers/scsi/imm.c

/* imm.c   --  low level driver for the IOMEGA MatchMaker
 * parallel port SCSI host adapter.
 * 
 * (The IMM is the embedded controller in the ZIP Plus drive.)
 * 
 * My unofficial company acronym list is 21 pages long:
 *      FLA:    Four letter acronym with built in facility for
 *              future expansion to five letters.
 */

#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/blkdev.h>
#include <linux/parport.h>
#include <linux/workqueue.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <asm/io.h>

#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_host.h>

/* The following #define is to avoid a clash with hosts.c */

#define IMM_PROBE_SPP   0x0001

#define IMM_PROBE_PS2   0x0002

#define IMM_PROBE_ECR   0x0010

#define IMM_PROBE_EPP17 0x0100

#define IMM_PROBE_EPP19 0x0200


typedef struct {
	
struct pardevice *dev;	/* Parport device entry         */
	
int base;		/* Actual port address          */
	
int base_hi;		/* Hi Base address for ECP-ISA chipset */
	
int mode;		/* Transfer mode                */
	
struct scsi_cmnd *cur_cmd;	/* Current queued command       */
	
struct delayed_work imm_tq;	/* Polling interrupt stuff       */
	
unsigned long jstart;	/* Jiffies at start             */
	
unsigned failed:1;	/* Failure flag                 */
	
unsigned dp:1;		/* Data phase present           */
	
unsigned rd:1;		/* Read data in data phase      */
	
unsigned wanted:1;	/* Parport sharing busy flag    */
	
unsigned int dev_no;	/* Device number                */
	
wait_queue_head_t *waiting;
	
struct Scsi_Host *host;
	
struct list_head list;
} 
imm_struct;

static void imm_reset_pulse(unsigned int base);
static int device_check(imm_struct *dev);

#include "imm.h"



static inline imm_struct *imm_dev(struct Scsi_Host *host)
{
	return *(imm_struct **)&host->hostdata;
}

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static DEFINE_SPINLOCK(arbitration_lock);



static void got_it(imm_struct *dev)
{
	dev->base = dev->dev->port->base;
	if (dev->cur_cmd)
		dev->cur_cmd->SCp.phase = 1;
	else
		wake_up(dev->waiting);
}

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static void imm_wakeup(void *ref)
{
	imm_struct *dev = (imm_struct *) ref;
	unsigned long flags;

	spin_lock_irqsave(&arbitration_lock, flags);
	if (dev->wanted) {
		if (parport_claim(dev->dev) == 0) {
			got_it(dev);
			dev->wanted = 0;
		}
	}
	spin_unlock_irqrestore(&arbitration_lock, flags);
}

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static int imm_pb_claim(imm_struct *dev)
{
	unsigned long flags;
	int res = 1;
	spin_lock_irqsave(&arbitration_lock, flags);
	if (parport_claim(dev->dev) == 0) {
		got_it(dev);
		res = 0;
	}
	dev->wanted = res;
	spin_unlock_irqrestore(&arbitration_lock, flags);
	return res;
}

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static void imm_pb_dismiss(imm_struct *dev)
{
	unsigned long flags;
	int wanted;
	spin_lock_irqsave(&arbitration_lock, flags);
	wanted = dev->wanted;
	dev->wanted = 0;
	spin_unlock_irqrestore(&arbitration_lock, flags);
	if (!wanted)
		parport_release(dev->dev);
}

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static inline void imm_pb_release(imm_struct *dev)
{
	parport_release(dev->dev);
}

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/* This is to give the imm driver a way to modify the timings (and other
 * parameters) by writing to the /proc/scsi/imm/0 file.
 * Very simple method really... (Too simple, no error checking :( )
 * Reason: Kernel hackers HATE having to unload and reload modules for
 * testing...
 * Also gives a method to use a script to obtain optimum timings (TODO)
 */


static int imm_write_info(struct Scsi_Host *host, char *buffer, int length)
{
	imm_struct *dev = imm_dev(host);

	if ((length > 5) && (strncmp(buffer, "mode=", 5) == 0)) {
		dev->mode = simple_strtoul(buffer + 5, NULL, 0);
		return length;
	}
	printk("imm /proc: invalid variable\n");
	return -EINVAL;
}

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static int imm_show_info(struct seq_file *m, struct Scsi_Host *host)
{
	imm_struct *dev = imm_dev(host);

	seq_printf(m, "Version : %s\n", IMM_VERSION);
	seq_printf(m, "Parport : %s\n", dev->dev->port->name);
	seq_printf(m, "Mode    : %s\n", IMM_MODE_STRING[dev->mode]);
	return 0;
}

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#if IMM_DEBUG > 0

#define imm_fail(x,y) printk("imm: imm_fail(%i) from %s at line %d\n",\
           y, __func__, __LINE__); imm_fail_func(x,y);
static inline void

imm_fail_func(imm_struct *dev, int error_code)
#else
static inline void
imm_fail(imm_struct *dev, int error_code)
#endif
{
	/* If we fail a device then we trash status / message bytes */
	if (dev->cur_cmd) {
		dev->cur_cmd->result = error_code << 16;
		dev->failed = 1;
	}
}

/*
 * Wait for the high bit to be set.
 * 
 * In principle, this could be tied to an interrupt, but the adapter
 * doesn't appear to be designed to support interrupts.  We spin on
 * the 0x80 ready bit. 
 */


static unsigned char imm_wait(imm_struct *dev)
{
	int k;
	unsigned short ppb = dev->base;
	unsigned char r;

	w_ctr(ppb, 0x0c);

	k = IMM_SPIN_TMO;
	do {
		r = r_str(ppb);
		k--;
		udelay(1);
	}
	while (!(r & 0x80) && (k));

	/*
         * STR register (LPT base+1) to SCSI mapping:
         *
         * STR      imm     imm
         * ===================================
         * 0x80     S_REQ   S_REQ
         * 0x40     !S_BSY  (????)
         * 0x20     !S_CD   !S_CD
         * 0x10     !S_IO   !S_IO
         * 0x08     (????)  !S_BSY
         *
         * imm      imm     meaning
         * ==================================
         * 0xf0     0xb8    Bit mask
         * 0xc0     0x88    ZIP wants more data
         * 0xd0     0x98    ZIP wants to send more data
         * 0xe0     0xa8    ZIP is expecting SCSI command data
         * 0xf0     0xb8    end of transfer, ZIP is sending status
         */
	w_ctr(ppb, 0x04);
	if (k)
		return (r & 0xb8);

	/* Counter expired - Time out occurred */
	imm_fail(dev, DID_TIME_OUT);
	printk("imm timeout in imm_wait\n");
	return 0;		/* command timed out */
}

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static int imm_negotiate(imm_struct * tmp)
{
	/*
         * The following is supposedly the IEEE 1284-1994 negotiate
         * sequence. I have yet to obtain a copy of the above standard
         * so this is a bit of a guess...
         *
         * A fair chunk of this is based on the Linux parport implementation
         * of IEEE 1284.
         *
         * Return 0 if data available
         *        1 if no data available
         */

	unsigned short base = tmp->base;
	unsigned char a, mode;

	switch (tmp->mode) {
	case IMM_NIBBLE:
		mode = 0x00;
		break;
	case IMM_PS2:
		mode = 0x01;
		break;
	default:
		return 0;
	}

	w_ctr(base, 0x04);
	udelay(5);
	w_dtr(base, mode);
	udelay(100);
	w_ctr(base, 0x06);
	udelay(5);
	a = (r_str(base) & 0x20) ? 0 : 1;
	udelay(5);
	w_ctr(base, 0x07);
	udelay(5);
	w_ctr(base, 0x06);

	if (a) {
		printk
		    ("IMM: IEEE1284 negotiate indicates no data available.\n");
		imm_fail(tmp, DID_ERROR);
	}
	return a;
}

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/* 
 * Clear EPP timeout bit. 
 */


static inline void epp_reset(unsigned short ppb)
{
	int i;

	i = r_str(ppb);
	w_str(ppb, i);
	w_str(ppb, i & 0xfe);
}

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/* 
 * Wait for empty ECP fifo (if we are in ECP fifo mode only)
 */


static inline void ecp_sync(imm_struct *dev)
{
	int i, ppb_hi = dev->base_hi;

	if (ppb_hi == 0)
		return;

	if ((r_ecr(ppb_hi) & 0xe0) == 0x60) {	/* mode 011 == ECP fifo mode */
		for (i = 0; i < 100; i++) {
			if (r_ecr(ppb_hi) & 0x01)
				return;
			udelay(5);
		}
		printk("imm: ECP sync failed as data still present in FIFO.\n");
	}
}

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static int imm_byte_out(unsigned short base, const char *buffer, int len)
{
	int i;

	w_ctr(base, 0x4);	/* apparently a sane mode */
	for (i = len >> 1; i; i--) {
		w_dtr(base, *buffer++);
		w_ctr(base, 0x5);	/* Drop STROBE low */
		w_dtr(base, *buffer++);
		w_ctr(base, 0x0);	/* STROBE high + INIT low */
	}
	w_ctr(base, 0x4);	/* apparently a sane mode */
	return 1;		/* All went well - we hope! */
}

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static int imm_nibble_in(unsigned short base, char *buffer, int len)
{
	unsigned char l;
	int i;

	/*
         * The following is based on documented timing signals
         */
	w_ctr(base, 0x4);
	for (i = len; i; i--) {
		w_ctr(base, 0x6);
		l = (r_str(base) & 0xf0) >> 4;
		w_ctr(base, 0x5);
		*buffer++ = (r_str(base) & 0xf0) | l;
		w_ctr(base, 0x4);
	}
	return 1;		/* All went well - we hope! */
}

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static int imm_byte_in(unsigned short base, char *buffer, int len)
{
	int i;

	/*
         * The following is based on documented timing signals
         */
	w_ctr(base, 0x4);
	for (i = len; i; i--) {
		w_ctr(base, 0x26);
		*buffer++ = r_dtr(base);
		w_ctr(base, 0x25);
	}
	return 1;		/* All went well - we hope! */
}

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static int imm_out(imm_struct *dev, char *buffer, int len)
{
	unsigned short ppb = dev->base;
	int r = imm_wait(dev);

	/*
         * Make sure that:
         * a) the SCSI bus is BUSY (device still listening)
         * b) the device is listening
         */
	if ((r & 0x18) != 0x08) {
		imm_fail(dev, DID_ERROR);
		printk("IMM: returned SCSI status %2x\n", r);
		return 0;
	}
	switch (dev->mode) {
	case IMM_EPP_32:
	case IMM_EPP_16:
	case IMM_EPP_8:
		epp_reset(ppb);
		w_ctr(ppb, 0x4);
#ifdef CONFIG_SCSI_IZIP_EPP16
		if (!(((long) buffer | len) & 0x01))
			outsw(ppb + 4, buffer, len >> 1);
#else
		if (!(((long) buffer | len) & 0x03))
			outsl(ppb + 4, buffer, len >> 2);
#endif
		else
			outsb(ppb + 4, buffer, len);
		w_ctr(ppb, 0xc);
		r = !(r_str(ppb) & 0x01);
		w_ctr(ppb, 0xc);
		ecp_sync(dev);
		break;

	case IMM_NIBBLE:
	case IMM_PS2:
		/* 8 bit output, with a loop */
		r = imm_byte_out(ppb, buffer, len);
		break;

	default:
		printk("IMM: bug in imm_out()\n");
		r = 0;
	}
	return r;
}

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static int imm_in(imm_struct *dev, char *buffer, int len)
{
	unsigned short ppb = dev->base;
	int r = imm_wait(dev);

	/*
         * Make sure that:
         * a) the SCSI bus is BUSY (device still listening)
         * b) the device is sending data
         */
	if ((r & 0x18) != 0x18) {
		imm_fail(dev, DID_ERROR);
		return 0;
	}
	switch (dev->mode) {
	case IMM_NIBBLE:
		/* 4 bit input, with a loop */
		r = imm_nibble_in(ppb, buffer, len);
		w_ctr(ppb, 0xc);
		break;

	case IMM_PS2:
		/* 8 bit input, with a loop */
		r = imm_byte_in(ppb, buffer, len);
		w_ctr(ppb, 0xc);
		break;

	case IMM_EPP_32:
	case IMM_EPP_16:
	case IMM_EPP_8:
		epp_reset(ppb);
		w_ctr(ppb, 0x24);
#ifdef CONFIG_SCSI_IZIP_EPP16
		if (!(((long) buffer | len) & 0x01))
			insw(ppb + 4, buffer, len >> 1);
#else
		if (!(((long) buffer | len) & 0x03))
			insl(ppb + 4, buffer, len >> 2);
#endif
		else
			insb(ppb + 4, buffer, len);
		w_ctr(ppb, 0x2c);
		r = !(r_str(ppb) & 0x01);
		w_ctr(ppb, 0x2c);
		ecp_sync(dev);
		break;

	default:
		printk("IMM: bug in imm_ins()\n");
		r = 0;
		break;
	}
	return r;
}

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static int imm_cpp(unsigned short ppb, unsigned char b)
{
	/*
         * Comments on udelay values refer to the
         * Command Packet Protocol (CPP) timing diagram.
         */

	unsigned char s1, s2, s3;
	w_ctr(ppb, 0x0c);
	udelay(2);		/* 1 usec - infinite */
	w_dtr(ppb, 0xaa);
	udelay(10);		/* 7 usec - infinite */
	w_dtr(ppb, 0x55);
	udelay(10);		/* 7 usec - infinite */
	w_dtr(ppb, 0x00);
	udelay(10);		/* 7 usec - infinite */
	w_dtr(ppb, 0xff);
	udelay(10);		/* 7 usec - infinite */
	s1 = r_str(ppb) & 0xb8;
	w_dtr(ppb, 0x87);
	udelay(10);		/* 7 usec - infinite */
	s2 = r_str(ppb) & 0xb8;
	w_dtr(ppb, 0x78);
	udelay(10);		/* 7 usec - infinite */
	s3 = r_str(ppb) & 0x38;
	/*
         * Values for b are:
         * 0000 00aa    Assign address aa to current device
         * 0010 00aa    Select device aa in EPP Winbond mode
         * 0010 10aa    Select device aa in EPP mode
         * 0011 xxxx    Deselect all devices
         * 0110 00aa    Test device aa
         * 1101 00aa    Select device aa in ECP mode
         * 1110 00aa    Select device aa in Compatible mode
         */
	w_dtr(ppb, b);
	udelay(2);		/* 1 usec - infinite */
	w_ctr(ppb, 0x0c);
	udelay(10);		/* 7 usec - infinite */
	w_ctr(ppb, 0x0d);
	udelay(2);		/* 1 usec - infinite */
	w_ctr(ppb, 0x0c);
	udelay(10);		/* 7 usec - infinite */
	w_dtr(ppb, 0xff);
	udelay(10);		/* 7 usec - infinite */

	/*
         * The following table is electrical pin values.
         * (BSY is inverted at the CTR register)
         *
         *       BSY  ACK  POut SEL  Fault
         * S1    0    X    1    1    1
         * S2    1    X    0    1    1
         * S3    L    X    1    1    S
         *
         * L => Last device in chain
         * S => Selected
         *
         * Observered values for S1,S2,S3 are:
         * Disconnect => f8/58/78
         * Connect    => f8/58/70
         */
	if ((s1 == 0xb8) && (s2 == 0x18) && (s3 == 0x30))
		return 1;	/* Connected */
	if ((s1 == 0xb8) && (s2 == 0x18) && (s3 == 0x38))
		return 0;	/* Disconnected */

	return -1;		/* No device present */
}

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static inline int imm_connect(imm_struct *dev, int flag)
{
	unsigned short ppb = dev->base;

	imm_cpp(ppb, 0xe0);	/* Select device 0 in compatible mode */
	imm_cpp(ppb, 0x30);	/* Disconnect all devices */

	if ((dev->mode == IMM_EPP_8) ||
	    (dev->mode == IMM_EPP_16) ||
	    (dev->mode == IMM_EPP_32))
		return imm_cpp(ppb, 0x28);	/* Select device 0 in EPP mode */
	return imm_cpp(ppb, 0xe0);	/* Select device 0 in compatible mode */
}

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static void imm_disconnect(imm_struct *dev)
{
	imm_cpp(dev->base, 0x30);	/* Disconnect all devices */
}

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static int imm_select(imm_struct *dev, int target)
{
	int k;
	unsigned short ppb = dev->base;

	/*
         * Firstly we want to make sure there is nothing
         * holding onto the SCSI bus.
         */
	w_ctr(ppb, 0xc);

	k = IMM_SELECT_TMO;
	do {
		k--;
	} while ((r_str(ppb) & 0x08) && (k));

	if (!k)
		return 0;

	/*
         * Now assert the SCSI ID (HOST and TARGET) on the data bus
         */
	w_ctr(ppb, 0x4);
	w_dtr(ppb, 0x80 | (1 << target));
	udelay(1);

	/*
         * Deassert SELIN first followed by STROBE
         */
	w_ctr(ppb, 0xc);
	w_ctr(ppb, 0xd);

	/*
         * ACK should drop low while SELIN is deasserted.
         * FAULT should drop low when the SCSI device latches the bus.
         */
	k = IMM_SELECT_TMO;
	do {
		k--;
	}
	while (!(r_str(ppb) & 0x08) && (k));

	/*
         * Place the interface back into a sane state (status mode)
         */
	w_ctr(ppb, 0xc);
	return (k) ? 1 : 0;
}

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33.33%
Al Viro
11
7.24%
2
66.67%
Total
152
100.00%
3
100.00%



static int imm_init(imm_struct *dev)
{
	if (imm_connect(dev, 0) != 1)
		return -EIO;
	imm_reset_pulse(dev->base);
	mdelay(1);	/* Delay to allow devices to settle */
	imm_disconnect(dev);
	mdelay(1);	/* Another delay to allow devices to settle */
	return device_check(dev);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Linus Torvalds (pre-git)
36
65.45%
1
20.00%
Al Viro
15
27.27%
3
60.00%
Jeff Garzik
4
7.27%
1
20.00%
Total
55
100.00%
5
100.00%



static inline int imm_send_command(struct scsi_cmnd *cmd)
{
	imm_struct *dev = imm_dev(cmd->device->host);
	int k;

	/* NOTE: IMM uses byte pairs */
	for (k = 0; k < cmd->cmd_len; k += 2)
		if (!imm_out(dev, &cmd->cmnd[k], 2))
			return 0;
	return 1;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Linus Torvalds (pre-git)
58
84.06%
1
25.00%
Al Viro
7
10.14%
1
25.00%
Andrew Morton
2
2.90%
1
25.00%
Christoph Hellwig
2
2.90%
1
25.00%
Total
69
100.00%
4
100.00%

/*
 * The bulk flag enables some optimisations in the data transfer loops,
 * it should be true for any command that transfers data in integral
 * numbers of sectors.
 * 
 * The driver appears to remain stable if we speed up the parallel port
 * i/o in this function, but not elsewhere.
 */


static int imm_completion(struct scsi_cmnd *cmd)
{
	/* Return codes:
         * -1     Error
         *  0     Told to schedule
         *  1     Finished data transfer
         */
	imm_struct *dev = imm_dev(cmd->device->host);
	unsigned short ppb = dev->base;
	unsigned long start_jiffies = jiffies;

	unsigned char r, v;
	int fast, bulk, status;

	v = cmd->cmnd[0];
	bulk = ((v == READ_6) ||
		(v == READ_10) || (v == WRITE_6) || (v == WRITE_10));

	/*
         * We only get here if the drive is ready to comunicate,
         * hence no need for a full imm_wait.
         */
	w_ctr(ppb, 0x0c);
	r = (r_str(ppb) & 0xb8);

	/*
         * while (device is not ready to send status byte)
         *     loop;
         */
	while (r != (unsigned char) 0xb8) {
		/*
                 * If we have been running for more than a full timer tick
                 * then take a rest.
                 */
		if (time_after(jiffies, start_jiffies + 1))
			return 0;

		/*
                 * FAIL if:
                 * a) Drive status is screwy (!ready && !present)
                 * b) Drive is requesting/sending more data than expected
                 */
		if (((r & 0x88) != 0x88) || (cmd->SCp.this_residual <= 0)) {
			imm_fail(dev, DID_ERROR);
			return -1;	/* ERROR_RETURN */
		}
		/* determine if we should use burst I/O */
		if (dev->rd == 0) {
			fast = (bulk
				&& (cmd->SCp.this_residual >=
				    IMM_BURST_SIZE)) ? IMM_BURST_SIZE : 2;
			status = imm_out(dev, cmd->SCp.ptr, fast);
		} else {
			fast = (bulk
				&& (cmd->SCp.this_residual >=
				    IMM_BURST_SIZE)) ? IMM_BURST_SIZE : 1;
			status = imm_in(dev, cmd->SCp.ptr, fast);
		}

		cmd->SCp.ptr += fast;
		cmd->SCp.this_residual -= fast;

		if (!status) {
			imm_fail(dev, DID_BUS_BUSY);
			return -1;	/* ERROR_RETURN */
		}
		if (cmd->SCp.buffer && !cmd->SCp.this_residual) {
			/* if scatter/gather, advance to the next segment */
			if (cmd->SCp.buffers_residual--) {
				cmd->SCp.buffer++;
				cmd->SCp.this_residual =
				    cmd->SCp.buffer->length;
				cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);

				/*
                                 * Make sure that we transfer even number of bytes
                                 * otherwise it makes imm_byte_out() messy.
                                 */
				if (cmd->SCp.this_residual & 0x01)
					cmd->SCp.this_residual++;
			}
		}
		/* Now check to see if the drive is ready to comunicate */
		w_ctr(ppb, 0x0c);
		r = (r_str(ppb) & 0xb8);

		/* If not, drop back down to the scheduler and wait a timer tick */
		if (!(r & 0x80))
			return 0;
	}
	return 1;		/* FINISH_RETURN */
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Linus Torvalds (pre-git)
383
93.19%
2
25.00%
Al Viro
21
5.11%
2
25.00%
Christoph Hellwig
2
0.49%
1
12.50%
Andrew Morton
2
0.49%
1
12.50%
Linus Torvalds
2
0.49%
1
12.50%
Jens Axboe
1
0.24%
1
12.50%
Total
411
100.00%
8
100.00%

/*
 * Since the IMM itself doesn't generate interrupts, we use
 * the scheduler's task queue to generate a stream of call-backs and
 * complete the request when the drive is ready.
 */


static void imm_interrupt(struct work_struct *work)
{
	imm_struct *dev = container_of(work, imm_struct, imm_tq.work);
	struct scsi_cmnd *cmd = dev->cur_cmd;
	struct Scsi_Host *host = cmd->device->host;
	unsigned long flags;

	if (imm_engine(dev, cmd)) {
		schedule_delayed_work(&dev->imm_tq, 1);
		return;
	}
	/* Command must of completed hence it is safe to let go... */
#if IMM_DEBUG > 0
	switch ((cmd->result >> 16) & 0xff) {
	case DID_OK:
		break;
	case DID_NO_CONNECT:
		printk("imm: no device at SCSI ID %i\n", cmd->device->id);
		break;
	case DID_BUS_BUSY:
		printk("imm: BUS BUSY - EPP timeout detected\n");
		break;
	case DID_TIME_OUT:
		printk("imm: unknown timeout\n");
		break;
	case DID_ABORT:
		printk("imm: told to abort\n");
		break;
	case DID_PARITY:
		printk("imm: parity error (???)\n");
		break;
	case DID_ERROR:
		printk("imm: internal driver error\n");
		break;
	case DID_RESET:
		printk("imm: told to reset device\n");
		break;
	case DID_BAD_INTR:
		printk("imm: bad interrupt (???)\n");
		break;
	default:
		printk("imm: bad return code (%02x)\n",
		       (cmd->result >> 16) & 0xff);
	}
#endif

	if (cmd->SCp.phase > 1)
		imm_disconnect(dev);

	imm_pb_dismiss(dev);

	spin_lock_irqsave(host->host_lock, flags);
	dev->cur_cmd = NULL;
	cmd->scsi_done(cmd);
	spin_unlock_irqrestore(host->host_lock, flags);
	return;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Linus Torvalds (pre-git)
199
81.56%
2
18.18%
Linus Torvalds
15
6.15%
1
9.09%
David Howells
12
4.92%
1
9.09%
Al Viro
9
3.69%
3
27.27%
Randy Dunlap
3
1.23%
1
9.09%
Christoph Hellwig
2
0.82%
1
9.09%
Andrew Morton
2
0.82%
1
9.09%
Ingo Molnar
2
0.82%
1
9.09%
Total
244
100.00%
11
100.00%



static int imm_engine(imm_struct *dev, struct scsi_cmnd *cmd