arch/x86/kernel/scx200_32.c

   1 /*
   2  *  Copyright (c) 2001,2002 Christer Weinigel <wingel@nano-system.com>
   3  *
   4  *  National Semiconductor SCx200 support.
   5  */
   6
   7 #include <linux/module.h>
   8 #include <linux/errno.h>
   9 #include <linux/kernel.h>
  10 #include <linux/init.h>
  11 #include <linux/mutex.h>
  12 #include <linux/pci.h>
  13
  14 #include <linux/scx200.h>
  15 #include <linux/scx200_gpio.h>
  16
  17 /* Verify that the configuration block really is there */
  18 #define scx200_cb_probe(base) (inw((base) + SCx200_CBA) == (base))
  19
  20 #define NAME "scx200"
  21
  22 MODULE_AUTHOR("Christer Weinigel <wingel@nano-system.com>");
  23 MODULE_DESCRIPTION("NatSemi SCx200 Driver");
  24 MODULE_LICENSE("GPL");
  25
  26 unsigned scx200_gpio_base = 0;
  27 unsigned long scx200_gpio_shadow[2];
  28
  29 unsigned scx200_cb_base = 0;
  30
  31 static struct pci_device_id scx200_tbl[] = {
  32         { PCI_DEVICE(PCI_VENDOR_ID_NS, PCI_DEVICE_ID_NS_SCx200_BRIDGE) },
  33         { PCI_DEVICE(PCI_VENDOR_ID_NS, PCI_DEVICE_ID_NS_SC1100_BRIDGE) },
  34         { PCI_DEVICE(PCI_VENDOR_ID_NS, PCI_DEVICE_ID_NS_SCx200_XBUS)   },
  35         { PCI_DEVICE(PCI_VENDOR_ID_NS, PCI_DEVICE_ID_NS_SC1100_XBUS)   },
  36         { },
  37 };
  38 MODULE_DEVICE_TABLE(pci,scx200_tbl);
  39
  40 static int __devinit scx200_probe(struct pci_dev *, const struct pci_device_id *);
  41
  42 static struct pci_driver scx200_pci_driver = {
  43         .name = "scx200",
  44         .id_table = scx200_tbl,
  45         .probe = scx200_probe,
  46 };
  47
  48 static DEFINE_MUTEX(scx200_gpio_config_lock);
  49
  50 static void __devinit scx200_init_shadow(void)
  51 {
  52         int bank;
  53
  54         /* read the current values driven on the GPIO signals */
  55         for (bank = 0; bank < 2; ++bank)
  56                 scx200_gpio_shadow[bank] = inl(scx200_gpio_base + 0x10 * bank);
  57 }
  58
  59 static int __devinit scx200_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
  60 {
  61         unsigned base;
  62
  63         if (pdev->device == PCI_DEVICE_ID_NS_SCx200_BRIDGE ||
  64             pdev->device == PCI_DEVICE_ID_NS_SC1100_BRIDGE) {
  65                 base = pci_resource_start(pdev, 0);
  66                 printk(KERN_INFO NAME ": GPIO base 0x%x\n", base);
  67
  68                 if (!request_region(base, SCx200_GPIO_SIZE, "NatSemi SCx200 GPIO")) {
  69                         printk(KERN_ERR NAME ": can't allocate I/O for GPIOs\n");
  70                         return -EBUSY;
  71                 }
  72
  73                 scx200_gpio_base = base;
  74                 scx200_init_shadow();
  75
  76         } else {
  77                 /* find the base of the Configuration Block */
  78                 if (scx200_cb_probe(SCx200_CB_BASE_FIXED)) {
  79                         scx200_cb_base = SCx200_CB_BASE_FIXED;
  80                 } else {
  81                         int err;
  82
  83                         err = pci_read_config_dword(pdev, SCx200_CBA_SCRATCH, &base);
  84                         if (!err && scx200_cb_probe(base)) {
  85                                 scx200_cb_base = base;
  86                         } else {
  87                                 printk(KERN_WARNING NAME ": Configuration Block not found\n");
  88                                 return -ENODEV;
  89                         }
  90                 }
  91                 printk(KERN_INFO NAME ": Configuration Block base 0x%x\n", scx200_cb_base);
  92         }
  93
  94         return 0;
  95 }
  96
  97 u32 scx200_gpio_configure(unsigned index, u32 mask, u32 bits)
  98 {
  99         u32 config, new_config;
 100
 101         mutex_lock(&scx200_gpio_config_lock);
 102
 103         outl(index, scx200_gpio_base + 0x20);
 104         config = inl(scx200_gpio_base + 0x24);
 105
 106         new_config = (config & mask) | bits;
 107         outl(new_config, scx200_gpio_base + 0x24);
 108
 109         mutex_unlock(&scx200_gpio_config_lock);
 110
 111         return config;
 112 }
 113
 114 static int __init scx200_init(void)
 115 {
 116         printk(KERN_INFO NAME ": NatSemi SCx200 Driver\n");
 117
 118         return pci_register_driver(&scx200_pci_driver);
 119 }
 120
 121 static void __exit scx200_cleanup(void)
 122 {
 123         pci_unregister_driver(&scx200_pci_driver);
 124         release_region(scx200_gpio_base, SCx200_GPIO_SIZE);
 125 }
 126
 127 module_init(scx200_init);
 128 module_exit(scx200_cleanup);
 129
 130 EXPORT_SYMBOL(scx200_gpio_base);
 131 EXPORT_SYMBOL(scx200_gpio_shadow);
 132 EXPORT_SYMBOL(scx200_gpio_configure);
 133 EXPORT_SYMBOL(scx200_cb_base);