path: root/drivers/scsi/imm.c

// SPDX-License-Identifier: GPL-2.0-only
/* 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, bool autodetect);

#include "imm.h"

static unsigned int mode = IMM_AUTODETECT;
module_param(mode, uint, 0644);
MODULE_PARM_DESC(mode, "Transfer mode (0 = Autodetect, 1 = SPP 4-bit, "
	"2 = SPP 8-bit, 3 = EPP 8-bit, 4 = EPP 16-bit, 5 = EPP 32-bit");

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

static DEFINE_SPINLOCK(arbitration_lock);

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

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);
}

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;
}

static void <