drivers/parport/parport_amiga.c

   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
  37 static 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
  45 static unsigned char amiga_read_data(struct parport *p)
  46 {
  47         /* Triggers also /STROBE. This behavior cannot be changed */
  48         return ciaa.prb;
  49 }
  50
  51 #if 0
  52 static unsigned char control_pc_to_amiga(unsigned char control)
  53 {
  54         unsigned char ret = 0;
  55
  56         if (control & PARPORT_CONTROL_SELECT) /* XXX: What is SELECP? */
  57                 ;
  58         if (control & PARPORT_CONTROL_INIT) /* INITP */
  59                 /* reset connected to cpu reset pin */;
  60         if (control & PARPORT_CONTROL_AUTOFD) /* AUTOLF */
  61                 /* Not connected */;
  62         if (control & PARPORT_CONTROL_STROBE) /* Strobe */
  63                 /* Handled only directly by hardware */;
  64         return ret;
  65 }
  66 #endif
  67
  68 static unsigned char control_amiga_to_pc(unsigned char control)
  69 {
  70         return PARPORT_CONTROL_SELECT |
  71               PARPORT_CONTROL_AUTOFD | PARPORT_CONTROL_STROBE;
  72         /* fake value: interrupt enable, select in, no reset,
  73         no autolf, no strobe - seems to be closest the wiring diagram */
  74 }
  75
  76 static void amiga_write_control(struct parport *p, unsigned char control)
  77 {
  78         DPRINTK(KERN_DEBUG "write_control %02x\n",control);
  79         /* No implementation possible */
  80 }
  81
  82 static unsigned char amiga_read_control( struct parport *p)
  83 {
  84         DPRINTK(KERN_DEBUG "read_control \n");
  85         return control_amiga_to_pc(0);
  86 }
  87
  88 static unsigned char amiga_frob_control( struct parport *p, unsigned char mask, unsigned char val)
  89 {
  90         unsigned char old;
  91
  92         DPRINTK(KERN_DEBUG "frob_control mask %02x, value %02x\n",mask,val);
  93         old = amiga_read_control(p);
  94         amiga_write_control(p, (old & ~mask) ^ val);
  95         return old;
  96 }
  97
  98 #if 0 /* currently unused */
  99 static unsigned char status_pc_to_amiga(unsigned char status)
 100 {
 101         unsigned char ret = 1;
 102
 103         if (status & PARPORT_STATUS_BUSY) /* Busy */
 104                 ret &= ~1;
 105         if (status & PARPORT_STATUS_ACK) /* Ack */
 106                 /* handled in hardware */;
 107         if (status & PARPORT_STATUS_PAPEROUT) /* PaperOut */
 108                 ret |= 2;
 109         if (status & PARPORT_STATUS_SELECT) /* select */
 110                 ret |= 4;
 111         if (status & PARPORT_STATUS_ERROR) /* error */
 112                 /* not connected */;
 113         return ret;
 114 }
 115 #endif
 116
 117 static unsigned char status_amiga_to_pc(unsigned char status)
 118 {
 119         unsigned char ret = PARPORT_STATUS_BUSY | PARPORT_STATUS_ACK | PARPORT_STATUS_ERROR;
 120
 121         if (status & 1) /* Busy */
 122                 ret &= ~PARPORT_STATUS_BUSY;
 123         if (status & 2) /* PaperOut */
 124                 ret |= PARPORT_STATUS_PAPEROUT;
 125         if (status & 4) /* Selected */
 126                 ret |= PARPORT_STATUS_SELECT;
 127         /* the rest is not connected or handled autonomously in hardware */
 128
 129         return ret;
 130 }
 131
 132 static unsigned char amiga_read_status(struct parport *p)
 133 {
 134         unsigned char status;
 135
 136         status = status_amiga_to_pc(ciab.pra & 7);
 137         DPRINTK(KERN_DEBUG "read_status %02x\n", status);
 138         return status;
 139 }
 140
 141 static void amiga_enable_irq(struct parport *p)
 142 {
 143         enable_irq(IRQ_AMIGA_CIAA_FLG);
 144 }
 145
 146 static void amiga_disable_irq(struct parport *p)
 147 {
 148         disable_irq(IRQ_AMIGA_CIAA_FLG);
 149 }
 150
 151 static void amiga_data_forward(struct parport *p)
 152 {
 153         DPRINTK(KERN_DEBUG "forward\n");
 154         ciaa.ddrb = 0xff; /* all pins output */
 155         mb();
 156 }
 157
 158 static void amiga_data_reverse(struct parport *p)
 159 {
 160         DPRINTK(KERN_DEBUG "reverse\n");
 161         ciaa.ddrb = 0; /* all pins input */
 162         mb();
 163 }
 164
 165 static void amiga_init_state(struct pardevice *dev, struct parport_state *s)
 166 {
 167         s->u.amiga.data = 0;
 168         s->u.amiga.datadir = 255;
 169         s->u.amiga.status = 0;
 170         s->u.amiga.statusdir = 0;
 171 }
 172
 173 static void amiga_save_state(struct parport *p, struct parport_state *s)
 174 {
 175         mb();
 176         s->u.amiga.data = ciaa.prb;
 177         s->u.amiga.datadir = ciaa.ddrb;
 178         s->u.amiga.status = ciab.pra & 7;
 179         s->u.amiga.statusdir = ciab.ddra & 7;
 180         mb();
 181 }
 182
 183 static void amiga_restore_state(struct parport *p, struct parport_state *s)
 184 {
 185         mb();
 186         ciaa.prb = s->u.amiga.data;
 187         ciaa.ddrb = s->u.amiga.datadir;
 188         ciab.pra |= (ciab.pra & 0xf8) | s->u.amiga.status;
 189         ciab.ddra |= (ciab.ddra & 0xf8) | s->u.amiga.statusdir;
 190         mb();
 191 }
 192
 193 static struct parport_operations pp_amiga_ops = {
 194         .write_data     = amiga_write_data,
 195         .read_data      = amiga_read_data,
 196
 197         .write_control  = amiga_write_control,
 198         .read_control   = amiga_read_control,
 199         .frob_control   = amiga_frob_control,
 200
 201         .read_status    = amiga_read_status,
 202
 203         .enable_irq     = amiga_enable_irq,
 204         .disable_irq    = amiga_disable_irq,
 205
 206         .data_forward   = amiga_data_forward,
 207         .data_reverse   = amiga_data_reverse,
 208
 209         .init_state     = amiga_init_state,
 210         .save_state     = amiga_save_state,
 211         .restore_state  = amiga_restore_state,
 212
 213         .epp_write_data = parport_ieee1284_epp_write_data,
 214         .epp_read_data  = parport_ieee1284_epp_read_data,
 215         .epp_write_addr = parport_ieee1284_epp_write_addr,
 216         .epp_read_addr  = parport_ieee1284_epp_read_addr,
 217
 218         .ecp_write_data = parport_ieee1284_ecp_write_data,
 219         .ecp_read_data  = parport_ieee1284_ecp_read_data,
 220         .ecp_write_addr = parport_ieee1284_ecp_write_addr,
 221
 222         .compat_write_data      = parport_ieee1284_write_compat,
 223         .nibble_read_data       = parport_ieee1284_read_nibble,
 224         .byte_read_data         = parport_ieee1284_read_byte,
 225
 226         .owner          = THIS_MODULE,
 227 };
 228
 229 /* ----------- Initialisation code --------------------------------- */
 230
 231 static int __init amiga_parallel_probe(struct platform_device *pdev)
 232 {
 233         struct parport *p;
 234         int err;
 235
 236         ciaa.ddrb = 0xff;
 237         ciab.ddra &= 0xf8;
 238         mb();
 239
 240         p = parport_register_port((unsigned long)&ciaa.prb, IRQ_AMIGA_CIAA_FLG,
 241                                    PARPORT_DMA_NONE, &pp_amiga_ops);
 242         if (!p)
 243                 return -EBUSY;
 244
 245         err = request_irq(IRQ_AMIGA_CIAA_FLG, parport_irq_handler, 0, p->name,
 246                           p);
 247         if (err)
 248                 goto out_irq;
 249
 250         printk(KERN_INFO "%s: Amiga built-in port using irq\n", p->name);
 251         /* XXX: set operating mode */
 252         parport_announce_port(p);
 253
 254         platform_set_drvdata(pdev, p);
 255
 256         return 0;
 257
 258 out_irq:
 259         parport_put_port(p);
 260         return err;
 261 }
 262
 263 static int __exit amiga_parallel_remove(struct platform_device *pdev)
 264 {
 265         struct parport *port = platform_get_drvdata(pdev);
 266
 267         parport_remove_port(port);
 268         if (port->irq != PARPORT_IRQ_NONE)
 269                 free_irq(IRQ_AMIGA_CIAA_FLG, port);
 270         parport_put_port(port);
 271         platform_set_drvdata(pdev, NULL);
 272         return 0;
 273 }
 274
 275 static struct platform_driver amiga_parallel_driver = {
 276         .remove = __exit_p(amiga_parallel_remove),
 277         .driver   = {
 278                 .name   = "amiga-parallel",
 279                 .owner  = THIS_MODULE,
 280         },
 281 };
 282
 283 static int __init amiga_parallel_init(void)
 284 {
 285         return platform_driver_probe(&amiga_parallel_driver,
 286                                      amiga_parallel_probe);
 287 }
 288
 289 module_init(amiga_parallel_init);
 290
 291 static void __exit amiga_parallel_exit(void)
 292 {
 293         platform_driver_unregister(&amiga_parallel_driver);
 294 }
 295
 296 module_exit(amiga_parallel_exit);
 297
 298 MODULE_AUTHOR("Joerg Dorchain <joerg@dorchain.net>");
 299 MODULE_DESCRIPTION("Parport Driver for Amiga builtin Port");
 300 MODULE_SUPPORTED_DEVICE("Amiga builtin Parallel Port");
 301 MODULE_LICENSE("GPL");
 302 MODULE_ALIAS("platform:amiga-parallel");