path: root/drivers/block/paride/pf.c

/* 
        pf.c    (c) 1997-8  Grant R. Guenther <grant@torque.net>
                            Under the terms of the GNU General Public License.

        This is the high-level driver for parallel port ATAPI disk
        drives based on chips supported by the paride module.

        By default, the driver will autoprobe for a single parallel
        port ATAPI disk drive, but if their individual parameters are
        specified, the driver can handle up to 4 drives.

        The behaviour of the pf driver can be altered by setting
        some parameters from the insmod command line.  The following
        parameters are adjustable:

            drive0      These four arguments can be arrays of       
            drive1      1-7 integers as follows:
            drive2
            drive3      <prt>,<pro>,<uni>,<mod>,<slv>,<lun>,<dly>

                        Where,

                <prt>   is the base of the parallel port address for
                        the corresponding drive.  (required)

                <pro>   is the protocol number for the adapter that
                        supports this drive.  These numbers are
                        logged by 'paride' when the protocol modules
                        are initialised.  (0 if not given)

                <uni>   for those adapters that support chained
                        devices, this is the unit selector for the
                        chain of devices on the given port.  It should
                        be zero for devices that don't support chaining.
                        (0 if not given)

                <mod>   this can be -1 to choose the best mode, or one
                        of the mode numbers supported by the adapter.
                        (-1 if not given)

                <slv>   ATAPI CDroms can be jumpered to master or slave.
                        Set this to 0 to choose the master drive, 1 to
                        choose the slave, -1 (the default) to choose the
                        first drive found.

		<lun>   Some ATAPI devices support multiple LUNs.
                        One example is the ATAPI PD/CD drive from
                        Matshita/Panasonic.  This device has a 
                        CD drive on LUN 0 and a PD drive on LUN 1.
                        By default, the driver will search for the
                        first LUN with a supported device.  Set 
                        this parameter to force it to use a specific
                        LUN.  (default -1)

                <dly>   some parallel ports require the driver to 
                        go more slowly.  -1 sets a default value that
                        should work with the chosen protocol.  Otherwise,
                        set this to a small integer, the larger it is
                        the slower the port i/o.  In some cases, setting
                        this to zero will speed up the device. (default -1)

	    major	You may use this parameter to override the
			default major number (47) that this driver
			will use.  Be sure to change the device
			name as well.

	    name	This parameter is a character string that
			contains the name the kernel will use for this
			device (in /proc output, for instance).
			(default "pf").

            cluster     The driver will attempt to aggregate requests
                        for adjacent blocks into larger multi-block
                        clusters.  The maximum cluster size (in 512
                        byte sectors) is set with this parameter.
                        (default 64)

            verbose     This parameter controls the amount of logging
                        that the driver will do.  Set it to 0 for
                        normal operation, 1 to see autoprobe progress
                        messages, or 2 to see additional debugging
                        output.  (default 0)
 
	    nice        This parameter controls the driver's use of
			idle CPU time, at the expense of some speed.

        If this driver is built into the kernel, you can use the
        following command line parameters, with the same values
        as the corresponding module parameters listed above:

            pf.drive0
            pf.drive1
            pf.drive2
            pf.drive3
	    pf.cluster
            pf.nice

        In addition, you can use the parameter pf.disable to disable
        the driver entirely.

*/

/* Changes:

	1.01	GRG 1998.05.03  Changes for SMP.  Eliminate sti().
				Fix for drives that don't clear STAT_ERR
			        until after next CDB delivered.
				Small change in pf_completion to round
				up transfer size.
	1.02    GRG 1998.06.16  Eliminated an Ugh
	1.03    GRG 1998.08.16  Use HZ in loop timings, extra debugging
	1.04    GRG 1998.09.24  Added jumbo support

*/

#define PF_VERSION      "1.04"
#define PF_MAJOR	47
#define PF_NAME		"pf"
#define PF_UNITS	4

#include <linux/types.h>

/* Here are things one can override from the insmod command.
   Most are autoprobed by paride unless set here.  Verbose is off
   by default.

*/

static bool verbose = 0;
static int major = PF_MAJOR;
static char *name = PF_NAME;
static int cluster = 64;
static int nice = 0;
static int disable = 0;

static int drive0[7] = { 0, 0, 0, -1, -1, -1, -1 };
static int drive1[7] = { 0, 0, 0, -1, -1, -1, -1 };
static int drive2[7] = { 0, 0, 0, -1, -1, -1, -1 };
static int drive3[7] = { 0, 0, 0, -1, -1, -1, -1 };

static int (*drives[4])[7] = {&drive0, &drive1, &drive2, &drive3};
static int pf_drive_count;

enum {D_PRT, D_PRO, D_UNI, D_MOD, D_SLV, D_LUN, D_DLY};

/* end of parameters */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/delay.h>
#include <linux/hdreg.h>
#include <linux/cdrom.h>
#include <linux/spinlock.h>
#include <linux/blk-mq.h>
#include <linux/blkpg.h>
#include <linux/mutex.h>
#include <linux/uaccess.h>

static DEFINE_MUTEX(pf_mutex);
static DEFINE_SPINLOCK(pf_spin_lock);

module_param(verbose, bool, 0644);
module_param(major, int, 0);
module_param(name, charp, 0);
module_param(cluster, int, 0);
module_param(nice, int, 0);
module_param_array(drive0, int, NULL, 0);
module_param_array(drive1, int, NULL, 0);
module_param_array(drive2, int, NULL, 0);
module_param_array(drive3, int, NULL, 0);

#include "paride.h"
#include "pseudo.h"

/* constants for faking geometry numbers */

#define PF_FD_MAX	8192	/* use FD geometry under this size */
#define PF_FD_HDS	2
#define PF_FD_SPT	18
#define PF_HD_HDS	64
#define PF_HD_SPT	32

#define PF_MAX_RETRIES  5
#define PF_TMO          800	/* interrupt timeout in jiffies */
#define PF_SPIN_DEL     50	/* spin delay in micro-seconds  */

#define PF_SPIN         (1000000*PF_TMO)/(HZ*PF_SPIN_DEL)