drivers/serial/acpi.c

   1 /*
   2  * serial/acpi.c
   3  * Copyright (c) 2002-2003 Matthew Wilcox for Hewlett-Packard
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  */
  10
  11 #include <linux/acpi.h>
  12 #include <linux/init.h>
  13 #include <linux/module.h>
  14 #include <linux/serial.h>
  15
  16 #include <acpi/acpi_bus.h>
  17
  18 #include <asm/io.h>
  19 #include <asm/serial.h>
  20
  21 static void acpi_serial_address(struct serial_struct *req, struct acpi_resource_address32 *addr32)
  22 {
  23         unsigned long size;
  24
  25         size = addr32->max_address_range - addr32->min_address_range + 1;
  26         req->iomap_base = addr32->min_address_range;
  27         req->iomem_base = ioremap(req->iomap_base, size);
  28         req->io_type = SERIAL_IO_MEM;
  29 }
  30
  31 static void acpi_serial_irq(struct serial_struct *req, struct acpi_resource_ext_irq *ext_irq)
  32 {
  33         if (ext_irq->number_of_interrupts > 0) {
  34 #ifdef CONFIG_IA64
  35                 req->irq = acpi_register_irq(ext_irq->interrupts[0],
  36                           ext_irq->active_high_low, ext_irq->edge_level);
  37 #else
  38                 req->irq = ext_irq->interrupts[0];
  39 #endif
  40         }
  41 }
  42
  43 static int acpi_serial_add(struct acpi_device *device)
  44 {
  45         acpi_status result;
  46         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
  47         struct serial_struct serial_req;
  48         int line, offset = 0;
  49
  50         memset(&serial_req, 0, sizeof(serial_req));
  51         result = acpi_get_current_resources(device->handle, &buffer);
  52         if (ACPI_FAILURE(result)) {
  53                 result = -ENODEV;
  54                 goto out;
  55         }
  56
  57         while (offset <= buffer.length) {
  58                 struct acpi_resource *res = buffer.pointer + offset;
  59                 if (res->length == 0)
  60                         break;
  61                 offset += res->length;
  62                 if (res->id == ACPI_RSTYPE_ADDRESS32) {
  63                         acpi_serial_address(&serial_req, &res->data.address32);
  64                 } else if (res->id == ACPI_RSTYPE_EXT_IRQ) {
  65                         acpi_serial_irq(&serial_req, &res->data.extended_irq);
  66                 }
  67         }
  68
  69         serial_req.baud_base = BASE_BAUD;
  70         serial_req.flags = ASYNC_SKIP_TEST|ASYNC_BOOT_AUTOCONF|ASYNC_AUTO_IRQ;
  71
  72         result = 0;
  73         line = register_serial(&serial_req);
  74         if (line < 0)
  75                 result = -ENODEV;
  76
  77  out:
  78         acpi_os_free(buffer.pointer);
  79         return result;
  80 }
  81
  82 static int acpi_serial_remove(struct acpi_device *device, int type)
  83 {
  84         return 0;
  85 }
  86
  87 static struct acpi_driver acpi_serial_driver = {
  88         .name =         "serial",
  89         .class =        "",
  90         .ids =          "PNP0501",
  91         .ops =  {
  92                 .add =          acpi_serial_add,
  93                 .remove =       acpi_serial_remove,
  94         },
  95 };
  96
  97 static int __init acpi_serial_init(void)
  98 {
  99         acpi_bus_register_driver(&acpi_serial_driver);
 100         return 0;
 101 }
 102
 103 static void __exit acpi_serial_exit(void)
 104 {
 105         acpi_bus_unregister_driver(&acpi_serial_driver);
 106 }
 107
 108 module_init(acpi_serial_init);
 109 module_exit(acpi_serial_exit);