arch/i386/kernel/scx200.c

   1 /* linux/arch/i386/kernel/scx200.c
   2
   3    Copyright (c) 2001,2002 Christer Weinigel <wingel@nano-system.com>
   4
   5    National Semiconductor SCx200 support. */
   6
   7 #include <linux/config.h>
   8 #include <linux/module.h>
   9 #include <linux/errno.h>
  10 #include <linux/kernel.h>
  11 #include <linux/init.h>
  12 #include <linux/pci.h>
  13
  14 #include <linux/scx200.h>
  15
  16 /* Verify that the configuration block really is there */
  17 #define scx200_cb_probe(base) (inw((base) + SCx200_CBA) == (base))
  18
  19 #define NAME "scx200"
  20
  21 MODULE_AUTHOR("Christer Weinigel <wingel@nano-system.com>");
  22 MODULE_DESCRIPTION("NatSemi SCx200 Driver");
  23 MODULE_LICENSE("GPL");
  24
  25 unsigned scx200_gpio_base = 0;
  26 long scx200_gpio_shadow[2];
  27
  28 unsigned scx200_cb_base = 0;
  29
  30 static struct pci_device_id scx200_tbl[] = {
  31         { PCI_DEVICE(PCI_VENDOR_ID_NS, PCI_DEVICE_ID_NS_SCx200_BRIDGE) },
  32         { PCI_DEVICE(PCI_VENDOR_ID_NS, PCI_DEVICE_ID_NS_SC1100_BRIDGE) },
  33         { PCI_DEVICE(PCI_VENDOR_ID_NS, PCI_DEVICE_ID_NS_SCx200_XBUS)   },
  34         { PCI_DEVICE(PCI_VENDOR_ID_NS, PCI_DEVICE_ID_NS_SC1100_XBUS)   },
  35         { },
  36 };
  37 MODULE_DEVICE_TABLE(pci,scx200_tbl);
  38
  39 static int __devinit scx200_probe(struct pci_dev *, const struct pci_device_id *);
  40
  41 static struct pci_driver scx200_pci_driver = {
  42         .name = "scx200",
  43         .id_table = scx200_tbl,
  44         .probe = scx200_probe,
  45 };
  46
  47 static DEFINE_SPINLOCK(scx200_gpio_config_lock);
  48
  49 static int __devinit scx200_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
  50 {
  51         int bank;
  52         unsigned base;
  53
  54         if (pdev->device == PCI_DEVICE_ID_NS_SCx200_BRIDGE ||
  55             pdev->device == PCI_DEVICE_ID_NS_SC1100_BRIDGE) {
  56                 base = pci_resource_start(pdev, 0);
  57                 printk(KERN_INFO NAME ": GPIO base 0x%x\n", base);
  58
  59                 if (request_region(base, SCx200_GPIO_SIZE, "NatSemi SCx200 GPIO") == 0) {
  60                         printk(KERN_ERR NAME ": can't allocate I/O for GPIOs\n");
  61                         return -EBUSY;
  62                 }
  63
  64                 scx200_gpio_base = base;
  65
  66                 /* read the current values driven on the GPIO signals */
  67                 for (bank = 0; bank < 2; ++bank)
  68                         scx200_gpio_shadow[bank] = inl(scx200_gpio_base + 0x10 * bank);
  69
  70         } else {
  71                 /* find the base of the Configuration Block */
  72                 if (scx200_cb_probe(SCx200_CB_BASE_FIXED)) {
  73                         scx200_cb_base = SCx200_CB_BASE_FIXED;
  74                 } else {
  75                         pci_read_config_dword(pdev, SCx200_CBA_SCRATCH, &base);
  76                         if (scx200_cb_probe(base)) {
  77                                 scx200_cb_base = base;
  78                         } else {
  79                                 printk(KERN_WARNING NAME ": Configuration Block not found\n");
  80                                 return -ENODEV;
  81                         }
  82                 }
  83                 printk(KERN_INFO NAME ": Configuration Block base 0x%x\n", scx200_cb_base);
  84         }
  85
  86         return 0;
  87 }
  88
  89 u32 scx200_gpio_configure(int index, u32 mask, u32 bits)
  90 {
  91         u32 config, new_config;
  92         unsigned long flags;
  93
  94         spin_lock_irqsave(&scx200_gpio_config_lock, flags);
  95
  96         outl(index, scx200_gpio_base + 0x20);
  97         config = inl(scx200_gpio_base + 0x24);
  98
  99         new_config = (config & mask) | bits;
 100         outl(new_config, scx200_gpio_base + 0x24);
 101
 102         spin_unlock_irqrestore(&scx200_gpio_config_lock, flags);
 103
 104         return config;
 105 }
 106
 107 #if 0
 108 void scx200_gpio_dump(unsigned index)
 109 {
 110         u32 config = scx200_gpio_configure(index, ~0, 0);
 111         printk(KERN_DEBUG "GPIO%02u: 0x%08lx", index, (unsigned long)config);
 112
 113         if (config & 1)
 114                 printk(" OE"); /* output enabled */
 115         else
 116                 printk(" TS"); /* tristate */
 117         if (config & 2)
 118                 printk(" PP"); /* push pull */
 119         else
 120                 printk(" OD"); /* open drain */
 121         if (config & 4)
 122                 printk(" PUE"); /* pull up enabled */
 123         else
 124                 printk(" PUD"); /* pull up disabled */
 125         if (config & 8)
 126                 printk(" LOCKED"); /* locked */
 127         if (config & 16)
 128                 printk(" LEVEL"); /* level input */
 129         else
 130                 printk(" EDGE"); /* edge input */
 131         if (config & 32)
 132                 printk(" HI"); /* trigger on rising edge */
 133         else
 134                 printk(" LO"); /* trigger on falling edge */
 135         if (config & 64)
 136                 printk(" DEBOUNCE"); /* debounce */
 137         printk("\n");
 138 }
 139 #endif  /*  0  */
 140
 141 static int __init scx200_init(void)
 142 {
 143         printk(KERN_INFO NAME ": NatSemi SCx200 Driver\n");
 144
 145         return pci_module_init(&scx200_pci_driver);
 146 }
 147
 148 static void __exit scx200_cleanup(void)
 149 {
 150         pci_unregister_driver(&scx200_pci_driver);
 151         release_region(scx200_gpio_base, SCx200_GPIO_SIZE);
 152 }
 153
 154 module_init(scx200_init);
 155 module_exit(scx200_cleanup);
 156
 157 EXPORT_SYMBOL(scx200_gpio_base);
 158 EXPORT_SYMBOL(scx200_gpio_shadow);
 159 EXPORT_SYMBOL(scx200_gpio_configure);
 160 EXPORT_SYMBOL(scx200_cb_base);
 161
 162 /*
 163     Local variables:
 164         compile-command: "make -k -C ../../.. SUBDIRS=arch/i386/kernel modules"
 165         c-basic-offset: 8
 166     End:
 167 */