linux/drivers/parport/parport_amiga.c
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   1/* Low-level parallel port routines for the Amiga built-in port
   2 *
   3 * Author: Joerg Dorchain <joerg@dorchain.net>
   4 *
   5 * This is a complete rewrite of the code, but based heaviy upon the old
   6 * lp_intern. code.
   7 *
   8 * The built-in Amiga parallel port provides one port at a fixed address
   9 * with 8 bidirectional data lines (D0 - D7) and 3 bidirectional status
  10 * lines (BUSY, POUT, SEL), 1 output control line /STROBE (raised automatically
  11 * in hardware when the data register is accessed), and 1 input control line
  12 * /ACK, able to cause an interrupt, but both not directly settable by
  13 * software.
  14 */
  15
  16#include <linux/module.h>
  17#include <linux/init.h>
  18#include <linux/parport.h>
  19#include <linux/ioport.h>
  20#include <linux/interrupt.h>
  21#include <linux/platform_device.h>
  22
  23#include <asm/setup.h>
  24#include <asm/amigahw.h>
  25#include <asm/irq.h>
  26#include <asm/io.h>
  27#include <asm/amigaints.h>
  28
  29#undef DEBUG
  30#ifdef DEBUG
  31#define DPRINTK printk
  32#else
  33#define DPRINTK(x...)   do { } while (0)
  34#endif
  35
  36
  37static void amiga_write_data(struct parport *p, unsigned char data)
  38{
  39        DPRINTK(KERN_DEBUG "write_data %c\n",data);
  40        /* Triggers also /STROBE. This behavior cannot be changed */
  41        ciaa.prb = data;
  42        mb();
  43}
  44
  45static unsigned char amiga_read_data(struct parport *p)
  46{
  47        /* Triggers also /STROBE. This behavior cannot be changed */
  48        return ciaa.prb;
  49}
  50
  51static unsigned char control_amiga_to_pc(unsigned char control)
  52{
  53        return PARPORT_CONTROL_SELECT |
  54              PARPORT_CONTROL_AUTOFD | PARPORT_CONTROL_STROBE;
  55        /* fake value: interrupt enable, select in, no reset,
  56        no autolf, no strobe - seems to be closest the wiring diagram */
  57}
  58
  59static void amiga_write_control(struct parport *p, unsigned char control)
  60{
  61        DPRINTK(KERN_DEBUG "write_control %02x\n",control);
  62        /* No implementation possible */
  63}
  64        
  65static unsigned char amiga_read_control( struct parport *p)
  66{
  67        DPRINTK(KERN_DEBUG "read_control \n");
  68        return control_amiga_to_pc(0);
  69}
  70
  71static unsigned char amiga_frob_control( struct parport *p, unsigned char mask, unsigned char val)
  72{
  73        unsigned char old;
  74
  75        DPRINTK(KERN_DEBUG "frob_control mask %02x, value %02x\n",mask,val);
  76        old = amiga_read_control(p);
  77        amiga_write_control(p, (old & ~mask) ^ val);
  78        return old;
  79}
  80
  81static unsigned char status_amiga_to_pc(unsigned char status)
  82{
  83        unsigned char ret = PARPORT_STATUS_BUSY | PARPORT_STATUS_ACK | PARPORT_STATUS_ERROR;
  84
  85        if (status & 1) /* Busy */
  86                ret &= ~PARPORT_STATUS_BUSY;
  87        if (status & 2) /* PaperOut */
  88                ret |= PARPORT_STATUS_PAPEROUT;
  89        if (status & 4) /* Selected */
  90                ret |= PARPORT_STATUS_SELECT;
  91        /* the rest is not connected or handled autonomously in hardware */
  92
  93        return ret;
  94}
  95
  96static unsigned char amiga_read_status(struct parport *p)
  97{
  98        unsigned char status;
  99
 100        status = status_amiga_to_pc(ciab.pra & 7);
 101        DPRINTK(KERN_DEBUG "read_status %02x\n", status);
 102        return status;
 103}
 104
 105static void amiga_enable_irq(struct parport *p)
 106{
 107        enable_irq(IRQ_AMIGA_CIAA_FLG);
 108}
 109
 110static void amiga_disable_irq(struct parport *p)
 111{
 112        disable_irq(IRQ_AMIGA_CIAA_FLG);
 113}
 114
 115static void amiga_data_forward(struct parport *p)
 116{
 117        DPRINTK(KERN_DEBUG "forward\n");
 118        ciaa.ddrb = 0xff; /* all pins output */
 119        mb();
 120}
 121
 122static void amiga_data_reverse(struct parport *p)
 123{
 124        DPRINTK(KERN_DEBUG "reverse\n");
 125        ciaa.ddrb = 0; /* all pins input */
 126        mb();
 127}
 128
 129static void amiga_init_state(struct pardevice *dev, struct parport_state *s)
 130{
 131        s->u.amiga.data = 0;
 132        s->u.amiga.datadir = 255;
 133        s->u.amiga.status = 0;
 134        s->u.amiga.statusdir = 0;
 135}
 136
 137static void amiga_save_state(struct parport *p, struct parport_state *s)
 138{
 139        mb();
 140        s->u.amiga.data = ciaa.prb;
 141        s->u.amiga.datadir = ciaa.ddrb;
 142        s->u.amiga.status = ciab.pra & 7;
 143        s->u.amiga.statusdir = ciab.ddra & 7;
 144        mb();
 145}
 146
 147static void amiga_restore_state(struct parport *p, struct parport_state *s)
 148{
 149        mb();
 150        ciaa.prb = s->u.amiga.data;
 151        ciaa.ddrb = s->u.amiga.datadir;
 152        ciab.pra |= (ciab.pra & 0xf8) | s->u.amiga.status;
 153        ciab.ddra |= (ciab.ddra & 0xf8) | s->u.amiga.statusdir;
 154        mb();
 155}
 156
 157static struct parport_operations pp_amiga_ops = {
 158        .write_data     = amiga_write_data,
 159        .read_data      = amiga_read_data,
 160
 161        .write_control  = amiga_write_control,
 162        .read_control   = amiga_read_control,
 163        .frob_control   = amiga_frob_control,
 164
 165        .read_status    = amiga_read_status,
 166
 167        .enable_irq     = amiga_enable_irq,
 168        .disable_irq    = amiga_disable_irq,
 169
 170        .data_forward   = amiga_data_forward,
 171        .data_reverse   = amiga_data_reverse,
 172
 173        .init_state     = amiga_init_state,
 174        .save_state     = amiga_save_state,
 175        .restore_state  = amiga_restore_state,
 176
 177        .epp_write_data = parport_ieee1284_epp_write_data,
 178        .epp_read_data  = parport_ieee1284_epp_read_data,
 179        .epp_write_addr = parport_ieee1284_epp_write_addr,
 180        .epp_read_addr  = parport_ieee1284_epp_read_addr,
 181
 182        .ecp_write_data = parport_ieee1284_ecp_write_data,
 183        .ecp_read_data  = parport_ieee1284_ecp_read_data,
 184        .ecp_write_addr = parport_ieee1284_ecp_write_addr,
 185
 186        .compat_write_data      = parport_ieee1284_write_compat,
 187        .nibble_read_data       = parport_ieee1284_read_nibble,
 188        .byte_read_data         = parport_ieee1284_read_byte,
 189
 190        .owner          = THIS_MODULE,
 191};
 192
 193/* ----------- Initialisation code --------------------------------- */
 194
 195static int __init amiga_parallel_probe(struct platform_device *pdev)
 196{
 197        struct parport *p;
 198        int err;
 199
 200        ciaa.ddrb = 0xff;
 201        ciab.ddra &= 0xf8;
 202        mb();
 203
 204        p = parport_register_port((unsigned long)&ciaa.prb, IRQ_AMIGA_CIAA_FLG,
 205                                   PARPORT_DMA_NONE, &pp_amiga_ops);
 206        if (!p)
 207                return -EBUSY;
 208
 209        err = request_irq(IRQ_AMIGA_CIAA_FLG, parport_irq_handler, 0, p->name,
 210                          p);
 211        if (err)
 212                goto out_irq;
 213
 214        printk(KERN_INFO "%s: Amiga built-in port using irq\n", p->name);
 215        /* XXX: set operating mode */
 216        parport_announce_port(p);
 217
 218        platform_set_drvdata(pdev, p);
 219
 220        return 0;
 221
 222out_irq:
 223        parport_put_port(p);
 224        return err;
 225}
 226
 227static int __exit amiga_parallel_remove(struct platform_device *pdev)
 228{
 229        struct parport *port = platform_get_drvdata(pdev);
 230
 231        parport_remove_port(port);
 232        if (port->irq != PARPORT_IRQ_NONE)
 233                free_irq(IRQ_AMIGA_CIAA_FLG, port);
 234        parport_put_port(port);
 235        platform_set_drvdata(pdev, NULL);
 236        return 0;
 237}
 238
 239static struct platform_driver amiga_parallel_driver = {
 240        .remove = __exit_p(amiga_parallel_remove),
 241        .driver   = {
 242                .name   = "amiga-parallel",
 243                .owner  = THIS_MODULE,
 244        },
 245};
 246
 247static int __init amiga_parallel_init(void)
 248{
 249        return platform_driver_probe(&amiga_parallel_driver,
 250                                     amiga_parallel_probe);
 251}
 252
 253module_init(amiga_parallel_init);
 254
 255static void __exit amiga_parallel_exit(void)
 256{
 257        platform_driver_unregister(&amiga_parallel_driver);
 258}
 259
 260module_exit(amiga_parallel_exit);
 261
 262MODULE_AUTHOR("Joerg Dorchain <joerg@dorchain.net>");
 263MODULE_DESCRIPTION("Parport Driver for Amiga builtin Port");
 264MODULE_SUPPORTED_DEVICE("Amiga builtin Parallel Port");
 265MODULE_LICENSE("GPL");
 266MODULE_ALIAS("platform:amiga-parallel");
 267
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