LXR linux-old/drivers/parport/parport

   1/* Low-level parallel port routines for Archimedes onboard hardware
   2 *
   3 * Author: Phil Blundell <philb@gnu.org>
   4 */
   5
   6/* This driver is for the parallel port hardware found on Acorn's old
   7 * range of Archimedes machines.  The A5000 and newer systems have PC-style
   8 * I/O hardware and should use the parport_pc driver instead.
   9 *
  10 * The Acorn printer port hardware is very simple.  There is a single 8-bit
  11 * write-only latch for the data port and control/status bits are handled
  12 * with various auxilliary input and output lines.  The port is not
  13 * bidirectional, does not support any modes other than SPP, and has only
  14 * a subset of the standard printer control lines connected.
  15 */
  16
  17#include <linux/threads.h>
  18#include <linux/delay.h>
  19#include <linux/errno.h>
  20#include <linux/interrupt.h>
  21#include <linux/ioport.h>
  22#include <linux/kernel.h>
  23#include <linux/slab.h>
  24#include <linux/parport.h>
  25
  26#include <asm/ptrace.h>
  27#include <asm/io.h>
  28#include <asm/arch/oldlatches.h>
  29#include <asm/arch/irqs.h>
  30
  31#define DATA_ADDRESS    0x3350010
  32
  33/* This is equivalent to the above and only used for request_region. */
  34#define PORT_BASE       0x80000000 | ((DATA_ADDRESS - IO_BASE) >> 2)
  35
  36/* The hardware can't read from the data latch, so we must use a soft
  37   copy. */
  38static unsigned char data_copy;
  39
  40/* These are pretty simple. We know the irq is never shared and the
  41   kernel does all the magic that's required. */
  42static void arc_enable_irq(struct parport *p)
  43{
  44        enable_irq(p->irq);
  45}
  46
  47static void arc_disable_irq(struct parport *p)
  48{
  49        disable_irq(p->irq);
  50}
  51
  52static void arc_interrupt(int irq, void *dev_id, struct pt_regs *regs)
  53{
  54        parport_generic_irq(irq, (struct parport *) dev_id, regs);
  55}
  56
  57static void arc_write_data(struct parport *p, unsigned char data)
  58{
  59        data_copy = data;
  60        outb_t(data, DATA_LATCH);
  61}
  62
  63static unsigned char arc_read_data(struct parport *p)
  64{
  65        return data_copy;
  66}
  67
  68static void arc_inc_use_count(void)
  69{
  70#ifdef MODULE
  71        MOD_INC_USE_COUNT;
  72#endif
  73}
  74
  75static void arc_dec_use_count(void)
  76{
  77#ifdef MODULE
  78        MOD_DEC_USE_COUNT;
  79#endif
  80}
  81
  82static struct parport_operations parport_arc_ops = 
  83{
  84        arc_write_data,
  85        arc_read_data,
  86
  87        arc_write_control,
  88        arc_read_control,
  89        arc_frob_control,
  90
  91        arc_read_status,
  92
  93        arc_enable_irq,
  94        arc_disable_irq,
  95
  96        arc_data_forward,
  97        arc_data_reverse,
  98
  99        arc_init_state,
 100        arc_save_state,
 101        arc_restore_state,
 102
 103        arc_inc_use_count,
 104        arc_dec_use_count,
 105
 106        parport_ieee1284_epp_write_data,
 107        parport_ieee1284_epp_read_data,
 108        parport_ieee1284_epp_write_addr,
 109        parport_ieee1284_epp_read_addr,
 110
 111        parport_ieee1284_ecp_write_data,
 112        parport_ieee1284_ecp_read_data,
 113        parport_ieee1284_ecp_write_addr,
 114        
 115        parport_ieee1284_write_compat,
 116        parport_ieee1284_read_nibble,
 117        parport_ieee1284_read_byte,
 118};
 119
 120/* --- Initialisation code -------------------------------- */
 121
 122int parport_arc_init(void)
 123{
 124        /* Archimedes hardware provides only one port, at a fixed address */
 125        struct parport *p;
 126
 127        if (check_region(PORT_BASE, 1))
 128                return 0;
 129
 130        p = parport_register_port (PORT_BASE, IRQ_PRINTERACK,
 131                                   PARPORT_DMA_NONE, &parport_arc_ops);
 132
 133        if (!p)
 134                return 0;
 135
 136        p->modes = PARPORT_MODE_ARCSPP;
 137        p->size = 1;
 138
 139        printk(KERN_INFO "%s: Archimedes on-board port, using irq %d\n",
 140               p->irq);
 141        parport_proc_register(p);
 142
 143        /* Tell the high-level drivers about the port. */
 144        parport_announce_port (p);
 145
 146        return 1;
 147}
 148