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 static 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
  59 static 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
  65 static 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
  71 static 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
  81 static 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
  96 static 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
 105 static void amiga_enable_irq(struct parport *p)
 106 {
 107         enable_irq(IRQ_AMIGA_CIAA_FLG);
 108 }
 109
 110 static void amiga_disable_irq(struct parport *p)
 111 {
 112         disable_irq(IRQ_AMIGA_CIAA_FLG);
 113 }
 114
 115 static 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
 122 static 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
 129 static 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
 137 static 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
 147 static 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
 157 static 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
 195 static 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
 222 out_irq:
 223         parport_put_port(p);
 224         return err;
 225 }
 226
 227 static 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         return 0;
 236 }
 237
 238 static struct platform_driver amiga_parallel_driver = {
 239         .remove = __exit_p(amiga_parallel_remove),
 240         .driver   = {
 241                 .name   = "amiga-parallel",
 242                 .owner  = THIS_MODULE,
 243         },
 244 };
 245
 246 module_platform_driver_probe(amiga_parallel_driver, amiga_parallel_probe);
 247
 248 MODULE_AUTHOR("Joerg Dorchain <joerg@dorchain.net>");
 249 MODULE_DESCRIPTION("Parport Driver for Amiga builtin Port");
 250 MODULE_SUPPORTED_DEVICE("Amiga builtin Parallel Port");
 251 MODULE_LICENSE("GPL");
 252 MODULE_ALIAS("platform:amiga-parallel");