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->minimum;
  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->address_length) {
  40                 port->iobase = io->minimum;
  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_extended_irq *ext_irq)
  49 {
  50         int rc;
  51
  52         if (ext_irq->interrupt_count > 0) {
  53                 rc = acpi_register_gsi(ext_irq->interrupts[0],
  54                            ext_irq->triggering, ext_irq->polarity);
  55                 if (rc < 0)
  56                         return AE_ERROR;
  57                 port->irq = rc;
  58         }
  59         return AE_OK;
  60 }
  61
  62 static acpi_status acpi_serial_irq(struct uart_port *port,
  63                                    struct acpi_resource_irq *irq)
  64 {
  65         int rc;
  66
  67         if (irq->interrupt_count > 0) {
  68                 rc = acpi_register_gsi(irq->interrupts[0],
  69                            irq->triggering, irq->polarity);
  70                 if (rc < 0)
  71                         return AE_ERROR;
  72                 port->irq = rc;
  73         }
  74         return AE_OK;
  75 }
  76
  77 static acpi_status acpi_serial_resource(struct acpi_resource *res, void *data)
  78 {
  79         struct uart_port *port = (struct uart_port *) data;
  80         struct acpi_resource_address64 addr;
  81         acpi_status status;
  82
  83         status = acpi_resource_to_address64(res, &addr);
  84         if (ACPI_SUCCESS(status))
  85                 return acpi_serial_mmio(port, &addr);
  86         else if (res->type == ACPI_RESOURCE_TYPE_IO)
  87                 return acpi_serial_port(port, &res->data.io);
  88         else if (res->type == ACPI_RESOURCE_TYPE_EXTENDED_IRQ)
  89                 return acpi_serial_ext_irq(port, &res->data.extended_irq);
  90         else if (res->type == ACPI_RESOURCE_TYPE_IRQ)
  91                 return acpi_serial_irq(port, &res->data.irq);
  92         return AE_OK;
  93 }
  94
  95 static int acpi_serial_add(struct acpi_device *device)
  96 {
  97         struct serial_private *priv;
  98         acpi_status status;
  99         struct uart_port port;
 100         int result;
 101
 102         memset(&port, 0, sizeof(struct uart_port));
 103
 104         port.uartclk = 1843200;
 105         port.flags = UPF_SKIP_TEST | UPF_BOOT_AUTOCONF;
 106
 107         priv = kmalloc(sizeof(struct serial_private), GFP_KERNEL);
 108         if (!priv) {
 109                 result = -ENOMEM;
 110                 goto fail;
 111         }
 112         memset(priv, 0, sizeof(*priv));
 113
 114         status = acpi_walk_resources(device->handle, METHOD_NAME__CRS,
 115                                      acpi_serial_resource, &port);
 116         if (ACPI_FAILURE(status)) {
 117                 result = -ENODEV;
 118                 goto fail;
 119         }
 120
 121         if (!port.mapbase && !port.iobase) {
 122                 printk(KERN_ERR "%s: no iomem or port address in %s _CRS\n",
 123                         __FUNCTION__, device->pnp.bus_id);
 124                 result = -ENODEV;
 125                 goto fail;
 126         }
 127
 128         priv->line = serial8250_register_port(&port);
 129         if (priv->line < 0) {
 130                 printk(KERN_WARNING "Couldn't register serial port %s: %d\n",
 131                         device->pnp.bus_id, priv->line);
 132                 result = -ENODEV;
 133                 goto fail;
 134         }
 135
 136         acpi_driver_data(device) = priv;
 137         return 0;
 138
 139 fail:
 140         kfree(priv);
 141
 142         return result;
 143 }
 144
 145 static int acpi_serial_remove(struct acpi_device *device, int type)
 146 {
 147         struct serial_private *priv;
 148
 149         if (!device || !acpi_driver_data(device))
 150                 return -EINVAL;
 151
 152         priv = acpi_driver_data(device);
 153         serial8250_unregister_port(priv->line);
 154         kfree(priv);
 155
 156         return 0;
 157 }
 158
 159 static struct acpi_driver acpi_serial_driver = {
 160         .name =         "serial",
 161         .class =        "",
 162         .ids =          "PNP0501",
 163         .ops =  {
 164                 .add =          acpi_serial_add,
 165                 .remove =       acpi_serial_remove,
 166         },
 167 };
 168
 169 static int __init acpi_serial_init(void)
 170 {
 171         return acpi_bus_register_driver(&acpi_serial_driver);
 172 }
 173
 174 static void __exit acpi_serial_exit(void)
 175 {
 176         acpi_bus_unregister_driver(&acpi_serial_driver);
 177 }
 178
 179 module_init(acpi_serial_init);
 180 module_exit(acpi_serial_exit);
 181
 182 MODULE_LICENSE("GPL");
 183 MODULE_DESCRIPTION("Generic 8250/16x50 ACPI serial driver");