drivers/serial/8250_acpi.c

   1 /*
   2  * Copyright (c) 2002-2003 Matthew Wilcox for Hewlett-Packard
   3  * Copyright (C) 2004 Hewlett-Packard Co
   4  *      Bjorn Helgaas <bjorn.helgaas@hp.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  */
  11
  12 #include <linux/acpi.h>
  13 #include <linux/init.h>
  14 #include <linux/module.h>
  15 #include <linux/serial_core.h>
  16
  17 #include <acpi/acpi_bus.h>
  18
  19 #include <asm/io.h>
  20
  21 #include "8250.h"
  22
  23 struct serial_private {
  24         int     line;
  25 };
  26
  27 static acpi_status acpi_serial_mmio(struct uart_port *port,
  28                                     struct acpi_resource_address64 *addr)
  29 {
  30         port->mapbase = addr->min_address_range;
  31         port->iotype = UPIO_MEM;
  32         port->flags |= UPF_IOREMAP;
  33         return AE_OK;
  34 }
  35
  36 static acpi_status acpi_serial_port(struct uart_port *port,
  37                                     struct acpi_resource_io *io)
  38 {
  39         if (io->range_length) {
  40                 port->iobase = io->min_base_address;
  41                 port->iotype = UPIO_PORT;
  42         } else
  43                 printk(KERN_ERR "%s: zero-length IO port range?\n", __FUNCTION__);
  44         return AE_OK;
  45 }
  46
  47 static acpi_status acpi_serial_ext_irq(struct uart_port *port,
  48                                        struct acpi_resource_ext_irq *ext_irq)
  49 {
  50         if (ext_irq->number_of_interrupts > 0)
  51                 port->irq = acpi_register_gsi(ext_irq->interrupts[0],
  52                            ext_irq->edge_level, ext_irq->active_high_low);
  53         return AE_OK;
  54 }
  55
  56 static acpi_status acpi_serial_irq(struct uart_port *port,
  57                                    struct acpi_resource_irq *irq)
  58 {
  59         if (irq->number_of_interrupts > 0)
  60                 port->irq = acpi_register_gsi(irq->interrupts[0],
  61                            irq->edge_level, irq->active_high_low);
  62         return AE_OK;
  63 }
  64
  65 static acpi_status acpi_serial_resource(struct acpi_resource *res, void *data)
  66 {
  67         struct uart_port *port = (struct uart_port *) data;
  68         struct acpi_resource_address64 addr;
  69         acpi_status status;
  70
  71         status = acpi_resource_to_address64(res, &addr);
  72         if (ACPI_SUCCESS(status))
  73                 return acpi_serial_mmio(port, &addr);
  74         else if (res->id == ACPI_RSTYPE_IO)
  75                 return acpi_serial_port(port, &res->data.io);
  76         else if (res->id == ACPI_RSTYPE_EXT_IRQ)
  77                 return acpi_serial_ext_irq(port, &res->data.extended_irq);
  78         else if (res->id == ACPI_RSTYPE_IRQ)
  79                 return acpi_serial_irq(port, &res->data.irq);
  80         return AE_OK;
  81 }
  82
  83 static int acpi_serial_add(struct acpi_device *device)
  84 {
  85         struct serial_private *priv;
  86         acpi_status status;
  87         struct uart_port port;
  88         int result;
  89
  90         memset(&port, 0, sizeof(struct uart_port));
  91
  92         port.uartclk = 1843200;
  93         port.flags = UPF_SKIP_TEST | UPF_BOOT_AUTOCONF;
  94
  95         priv = kmalloc(sizeof(struct serial_private), GFP_KERNEL);
  96         if (!priv) {
  97                 result = -ENOMEM;
  98                 goto fail;
  99         }
 100         memset(priv, 0, sizeof(*priv));
 101
 102         status = acpi_walk_resources(device->handle, METHOD_NAME__CRS,
 103                                      acpi_serial_resource, &port);
 104         if (ACPI_FAILURE(status)) {
 105                 result = -ENODEV;
 106                 goto fail;
 107         }
 108
 109         if (!port.mapbase && !port.iobase) {
 110                 printk(KERN_ERR "%s: no iomem or port address in %s _CRS\n",
 111                         __FUNCTION__, device->pnp.bus_id);
 112                 result = -ENODEV;
 113                 goto fail;
 114         }
 115
 116         priv->line = serial8250_register_port(&port);
 117         if (priv->line < 0) {
 118                 printk(KERN_WARNING "Couldn't register serial port %s: %d\n",
 119                         device->pnp.bus_id, priv->line);
 120                 result = -ENODEV;
 121                 goto fail;
 122         }
 123
 124         acpi_driver_data(device) = priv;
 125         return 0;
 126
 127 fail:
 128         kfree(priv);
 129
 130         return result;
 131 }
 132
 133 static int acpi_serial_remove(struct acpi_device *device, int type)
 134 {
 135         struct serial_private *priv;
 136
 137         if (!device || !acpi_driver_data(device))
 138                 return -EINVAL;
 139
 140         priv = acpi_driver_data(device);
 141         serial8250_unregister_port(priv->line);
 142         kfree(priv);
 143
 144         return 0;
 145 }
 146
 147 static struct acpi_driver acpi_serial_driver = {
 148         .name =         "serial",
 149         .class =        "",
 150         .ids =          "PNP0501",
 151         .ops =  {
 152                 .add =          acpi_serial_add,
 153                 .remove =       acpi_serial_remove,
 154         },
 155 };
 156
 157 static int __init acpi_serial_init(void)
 158 {
 159         return acpi_bus_register_driver(&acpi_serial_driver);
 160 }
 161
 162 static void __exit acpi_serial_exit(void)
 163 {
 164         acpi_bus_unregister_driver(&acpi_serial_driver);
 165 }
 166
 167 module_init(acpi_serial_init);
 168 module_exit(acpi_serial_exit);
 169
 170 MODULE_LICENSE("GPL");
 171 MODULE_DESCRIPTION("Generic 8250/16x50 ACPI serial driver");