/* Low-level parallel port routines for the Amiga built-in port
   *
   * Author: Joerg Dorchain <joerg@dorchain.net>
   *
   * This is a complete rewrite of the code, but based heaviy upon the old
   * lp_intern. code.
   *
   * The built-in Amiga parallel port provides one port at a fixed address
   * with 8 bidirectional data lines (D0 - D7) and 3 bidirectional status
   * lines (BUSY, POUT, SEL), 1 output control line /STROBE (raised automatically
   * in hardware when the data register is accessed), and 1 input control line
   * /ACK, able to cause an interrupt, but both not directly settable by
   * software.
   */
  
  #include <linux/module.h>
  #include <linux/init.h>
  #include <linux/parport.h>
  #include <linux/ioport.h>
  #include <linux/interrupt.h>

  #include <linux/platform_device.h>

  #include <asm/setup.h>
  #include <asm/amigahw.h>
  #include <asm/irq.h>
  #include <asm/io.h>
  #include <asm/amigaints.h>
  
  #undef DEBUG
  #ifdef DEBUG
  #define DPRINTK printk
  #else
  #define DPRINTK(x...)	do { } while (0)
  #endif

  
  static void amiga_write_data(struct parport *p, unsigned char data)
  {
  	DPRINTK(KERN_DEBUG "write_data %c
  ",data);
  	/* Triggers also /STROBE. This behavior cannot be changed */
  	ciaa.prb = data;
  	mb();
  }
  
  static unsigned char amiga_read_data(struct parport *p)
  {
  	/* Triggers also /STROBE. This behavior cannot be changed */
  	return ciaa.prb;
  }
  
  #if 0
  static unsigned char control_pc_to_amiga(unsigned char control)
  {
  	unsigned char ret = 0;
  
  	if (control & PARPORT_CONTROL_SELECT) /* XXX: What is SELECP? */
  		;
  	if (control & PARPORT_CONTROL_INIT) /* INITP */
  		/* reset connected to cpu reset pin */;
  	if (control & PARPORT_CONTROL_AUTOFD) /* AUTOLF */
  		/* Not connected */;
  	if (control & PARPORT_CONTROL_STROBE) /* Strobe */
  		/* Handled only directly by hardware */;
  	return ret;
  }
  #endif
  
  static unsigned char control_amiga_to_pc(unsigned char control)
  {
  	return PARPORT_CONTROL_SELECT |
  	      PARPORT_CONTROL_AUTOFD | PARPORT_CONTROL_STROBE;
  	/* fake value: interrupt enable, select in, no reset,
  	no autolf, no strobe - seems to be closest the wiring diagram */
  }
  
  static void amiga_write_control(struct parport *p, unsigned char control)
  {
  	DPRINTK(KERN_DEBUG "write_control %02x
  ",control);
  	/* No implementation possible */
  }
  	
  static unsigned char amiga_read_control( struct parport *p)
  {
  	DPRINTK(KERN_DEBUG "read_control 
  ");
  	return control_amiga_to_pc(0);
  }
  
  static unsigned char amiga_frob_control( struct parport *p, unsigned char mask, unsigned char val)
  {
  	unsigned char old;
  
  	DPRINTK(KERN_DEBUG "frob_control mask %02x, value %02x
  ",mask,val);
  	old = amiga_read_control(p);
  	amiga_write_control(p, (old & ~mask) ^ val);
  	return old;
  }
  
  #if 0 /* currently unused */
  static unsigned char status_pc_to_amiga(unsigned char status)
  {
  	unsigned char ret = 1;
  
  	if (status & PARPORT_STATUS_BUSY) /* Busy */
  		ret &= ~1;
  	if (status & PARPORT_STATUS_ACK) /* Ack */
  		/* handled in hardware */;
  	if (status & PARPORT_STATUS_PAPEROUT) /* PaperOut */
  		ret |= 2;
  	if (status & PARPORT_STATUS_SELECT) /* select */
  		ret |= 4;
  	if (status & PARPORT_STATUS_ERROR) /* error */
  		/* not connected */;
  	return ret;
  }
  #endif
  
  static unsigned char status_amiga_to_pc(unsigned char status)
  {
  	unsigned char ret = PARPORT_STATUS_BUSY | PARPORT_STATUS_ACK | PARPORT_STATUS_ERROR;
  
  	if (status & 1) /* Busy */
  		ret &= ~PARPORT_STATUS_BUSY;
  	if (status & 2) /* PaperOut */
  		ret |= PARPORT_STATUS_PAPEROUT;
  	if (status & 4) /* Selected */
  		ret |= PARPORT_STATUS_SELECT;
  	/* the rest is not connected or handled autonomously in hardware */
  
  	return ret;
  }
  
  static unsigned char amiga_read_status(struct parport *p)
  {
  	unsigned char status;
  
  	status = status_amiga_to_pc(ciab.pra & 7);
  	DPRINTK(KERN_DEBUG "read_status %02x
  ", status);
  	return status;
  }

  static void amiga_enable_irq(struct parport *p)
  {
  	enable_irq(IRQ_AMIGA_CIAA_FLG);
  }
  
  static void amiga_disable_irq(struct parport *p)
  {
  	disable_irq(IRQ_AMIGA_CIAA_FLG);
  }
  
  static void amiga_data_forward(struct parport *p)
  {
  	DPRINTK(KERN_DEBUG "forward
  ");
  	ciaa.ddrb = 0xff; /* all pins output */
  	mb();
  }
  
  static void amiga_data_reverse(struct parport *p)
  {
  	DPRINTK(KERN_DEBUG "reverse
  ");
  	ciaa.ddrb = 0; /* all pins input */
  	mb();
  }
  
  static void amiga_init_state(struct pardevice *dev, struct parport_state *s)
  {
  	s->u.amiga.data = 0;
  	s->u.amiga.datadir = 255;
  	s->u.amiga.status = 0;
  	s->u.amiga.statusdir = 0;
  }
  
  static void amiga_save_state(struct parport *p, struct parport_state *s)
  {
  	mb();
  	s->u.amiga.data = ciaa.prb;
  	s->u.amiga.datadir = ciaa.ddrb;
  	s->u.amiga.status = ciab.pra & 7;
  	s->u.amiga.statusdir = ciab.ddra & 7;
  	mb();
  }
  
  static void amiga_restore_state(struct parport *p, struct parport_state *s)
  {
  	mb();
  	ciaa.prb = s->u.amiga.data;
  	ciaa.ddrb = s->u.amiga.datadir;
  	ciab.pra |= (ciab.pra & 0xf8) | s->u.amiga.status;
  	ciab.ddra |= (ciab.ddra & 0xf8) | s->u.amiga.statusdir;
  	mb();
  }
  
  static struct parport_operations pp_amiga_ops = {
  	.write_data	= amiga_write_data,
  	.read_data	= amiga_read_data,
  
  	.write_control	= amiga_write_control,
  	.read_control	= amiga_read_control,
  	.frob_control	= amiga_frob_control,
  
  	.read_status	= amiga_read_status,
  
  	.enable_irq	= amiga_enable_irq,
  	.disable_irq	= amiga_disable_irq,
  
  	.data_forward	= amiga_data_forward,
  	.data_reverse	= amiga_data_reverse,
  
  	.init_state	= amiga_init_state,
  	.save_state	= amiga_save_state,
  	.restore_state	= amiga_restore_state,
  
  	.epp_write_data	= parport_ieee1284_epp_write_data,
  	.epp_read_data	= parport_ieee1284_epp_read_data,
  	.epp_write_addr	= parport_ieee1284_epp_write_addr,
  	.epp_read_addr	= parport_ieee1284_epp_read_addr,
  
  	.ecp_write_data	= parport_ieee1284_ecp_write_data,
  	.ecp_read_data	= parport_ieee1284_ecp_read_data,
  	.ecp_write_addr	= parport_ieee1284_ecp_write_addr,
  
  	.compat_write_data	= parport_ieee1284_write_compat,
  	.nibble_read_data	= parport_ieee1284_read_nibble,
  	.byte_read_data		= parport_ieee1284_read_byte,
  
  	.owner		= THIS_MODULE,
  };
  
  /* ----------- Initialisation code --------------------------------- */

  static int __init amiga_parallel_probe(struct platform_device *pdev)

  {
  	struct parport *p;
  	int err;

  	ciaa.ddrb = 0xff;
  	ciab.ddra &= 0xf8;
  	mb();
  
  	p = parport_register_port((unsigned long)&ciaa.prb, IRQ_AMIGA_CIAA_FLG,
  				   PARPORT_DMA_NONE, &pp_amiga_ops);
  	if (!p)

  		return -EBUSY;

  	err = request_irq(IRQ_AMIGA_CIAA_FLG, parport_irq_handler, 0, p->name,
  			  p);

  	if (err)
  		goto out_irq;

  	printk(KERN_INFO "%s: Amiga built-in port using irq
  ", p->name);
  	/* XXX: set operating mode */
  	parport_announce_port(p);

  	platform_set_drvdata(pdev, p);

  	return 0;
  
  out_irq:
  	parport_put_port(p);

  	return err;
  }

  static int __exit amiga_parallel_remove(struct platform_device *pdev)
  {
  	struct parport *port = platform_get_drvdata(pdev);
  
  	parport_remove_port(port);
  	if (port->irq != PARPORT_IRQ_NONE)
  		free_irq(IRQ_AMIGA_CIAA_FLG, port);
  	parport_put_port(port);
  	platform_set_drvdata(pdev, NULL);
  	return 0;
  }
  
  static struct platform_driver amiga_parallel_driver = {
  	.remove = __exit_p(amiga_parallel_remove),
  	.driver   = {
  		.name	= "amiga-parallel",
  		.owner	= THIS_MODULE,
  	},
  };
  
  static int __init amiga_parallel_init(void)
  {
  	return platform_driver_probe(&amiga_parallel_driver,
  				     amiga_parallel_probe);
  }
  
  module_init(amiga_parallel_init);
  
  static void __exit amiga_parallel_exit(void)

  {

  	platform_driver_unregister(&amiga_parallel_driver);

  }

  module_exit(amiga_parallel_exit);

  
  MODULE_AUTHOR("Joerg Dorchain <joerg@dorchain.net>");
  MODULE_DESCRIPTION("Parport Driver for Amiga builtin Port");
  MODULE_SUPPORTED_DEVICE("Amiga builtin Parallel Port");
  MODULE_LICENSE("GPL");

  MODULE_ALIAS("platform:amiga-parallel");