drivers/serial/8250_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,
  22                                 struct acpi_resource_address32 *addr32)
  23 {
  24         unsigned long size;
  25
  26         size = addr32->max_address_range - addr32->min_address_range + 1;
  27         req->iomap_base = addr32->min_address_range;
  28         req->iomem_base = ioremap(req->iomap_base, size);
  29         req->io_type = SERIAL_IO_MEM;
  30 }
  31
  32 static void acpi_serial_irq(struct serial_struct *req,
  33                             struct acpi_resource_ext_irq *ext_irq)
  34 {
  35         if (ext_irq->number_of_interrupts > 0) {
  36 #ifdef CONFIG_IA64
  37                 req->irq = acpi_register_irq(ext_irq->interrupts[0],
  38                           ext_irq->active_high_low, ext_irq->edge_level);
  39 #else
  40                 req->irq = ext_irq->interrupts[0];
  41 #endif
  42         }
  43 }
  44
  45 static int acpi_serial_add(struct acpi_device *device)
  46 {
  47         acpi_status result;
  48         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
  49         struct serial_struct serial_req;
  50         int line, offset = 0;
  51
  52         memset(&serial_req, 0, sizeof(serial_req));
  53         result = acpi_get_current_resources(device->handle, &buffer);
  54         if (ACPI_FAILURE(result)) {
  55                 result = -ENODEV;
  56                 goto out;
  57         }
  58
  59         while (offset <= buffer.length) {
  60                 struct acpi_resource *res = buffer.pointer + offset;
  61                 if (res->length == 0)
  62                         break;
  63                 offset += res->length;
  64                 if (res->id == ACPI_RSTYPE_ADDRESS32) {
  65                         acpi_serial_address(&serial_req, &res->data.address32);
  66                 } else if (res->id == ACPI_RSTYPE_EXT_IRQ) {
  67                         acpi_serial_irq(&serial_req, &res->data.extended_irq);
  68                 }
  69         }
  70
  71         serial_req.baud_base = BASE_BAUD;
  72         serial_req.flags = ASYNC_SKIP_TEST|ASYNC_BOOT_AUTOCONF|ASYNC_AUTO_IRQ;
  73
  74         result = 0;
  75         line = register_serial(&serial_req);
  76         if (line < 0)
  77                 result = -ENODEV;
  78
  79  out:
  80         acpi_os_free(buffer.pointer);
  81         return result;
  82 }
  83
  84 static int acpi_serial_remove(struct acpi_device *device, int type)
  85 {
  86         return 0;
  87 }
  88
  89 static struct acpi_driver acpi_serial_driver = {
  90         .name =         "serial",
  91         .class =        "",
  92         .ids =          "PNP0501",
  93         .ops =  {
  94                 .add =          acpi_serial_add,
  95                 .remove =       acpi_serial_remove,
  96         },
  97 };
  98
  99 static int __init acpi_serial_init(void)
 100 {
 101         return acpi_bus_register_driver(&acpi_serial_driver);
 102 }
 103
 104 static void __exit acpi_serial_exit(void)
 105 {
 106         acpi_bus_unregister_driver(&acpi_serial_driver);
 107 }
 108
 109 module_init(acpi_serial_init);
 110 module_exit(acpi_serial_exit);