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 #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 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_SPINLOCK(scx200_gpio_config_lock);
  49
  50 static int __devinit scx200_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
  51 {
  52         int bank;
  53         unsigned base;
  54
  55         if (pdev->device == PCI_DEVICE_ID_NS_SCx200_BRIDGE ||
  56             pdev->device == PCI_DEVICE_ID_NS_SC1100_BRIDGE) {
  57                 base = pci_resource_start(pdev, 0);
  58                 printk(KERN_INFO NAME ": GPIO base 0x%x\n", base);
  59
  60                 if (request_region(base, SCx200_GPIO_SIZE, "NatSemi SCx200 GPIO") == 0) {
  61                         printk(KERN_ERR NAME ": can't allocate I/O for GPIOs\n");
  62                         return -EBUSY;
  63                 }
  64
  65                 scx200_gpio_base = base;
  66
  67                 /* read the current values driven on the GPIO signals */
  68                 for (bank = 0; bank < 2; ++bank)
  69                         scx200_gpio_shadow[bank] = inl(scx200_gpio_base + 0x10 * bank);
  70
  71         } else {
  72                 /* find the base of the Configuration Block */
  73                 if (scx200_cb_probe(SCx200_CB_BASE_FIXED)) {
  74                         scx200_cb_base = SCx200_CB_BASE_FIXED;
  75                 } else {
  76                         pci_read_config_dword(pdev, SCx200_CBA_SCRATCH, &base);
  77                         if (scx200_cb_probe(base)) {
  78                                 scx200_cb_base = base;
  79                         } else {
  80                                 printk(KERN_WARNING NAME ": Configuration Block not found\n");
  81                                 return -ENODEV;
  82                         }
  83                 }
  84                 printk(KERN_INFO NAME ": Configuration Block base 0x%x\n", scx200_cb_base);
  85         }
  86
  87         return 0;
  88 }
  89
  90 u32 scx200_gpio_configure(int index, u32 mask, u32 bits)
  91 {
  92         u32 config, new_config;
  93         unsigned long flags;
  94
  95         spin_lock_irqsave(&scx200_gpio_config_lock, flags);
  96
  97         outl(index, scx200_gpio_base + 0x20);
  98         config = inl(scx200_gpio_base + 0x24);
  99
 100         new_config = (config & mask) | bits;
 101         outl(new_config, scx200_gpio_base + 0x24);
 102
 103         spin_unlock_irqrestore(&scx200_gpio_config_lock, flags);
 104
 105         return config;
 106 }
 107
 108 #if 0
 109 void scx200_gpio_dump(unsigned index)
 110 {
 111         u32 config = scx200_gpio_configure(index, ~0, 0);
 112         printk(KERN_DEBUG "GPIO%02u: 0x%08lx", index, (unsigned long)config);
 113
 114         if (config & 1)
 115                 printk(" OE"); /* output enabled */
 116         else
 117                 printk(" TS"); /* tristate */
 118         if (config & 2)
 119                 printk(" PP"); /* push pull */
 120         else
 121                 printk(" OD"); /* open drain */
 122         if (config & 4)
 123                 printk(" PUE"); /* pull up enabled */
 124         else
 125                 printk(" PUD"); /* pull up disabled */
 126         if (config & 8)
 127                 printk(" LOCKED"); /* locked */
 128         if (config & 16)
 129                 printk(" LEVEL"); /* level input */
 130         else
 131                 printk(" EDGE"); /* edge input */
 132         if (config & 32)
 133                 printk(" HI"); /* trigger on rising edge */
 134         else
 135                 printk(" LO"); /* trigger on falling edge */
 136         if (config & 64)
 137                 printk(" DEBOUNCE"); /* debounce */
 138         printk("\n");
 139 }
 140 #endif  /*  0  */
 141
 142 static int __init scx200_init(void)
 143 {
 144         printk(KERN_INFO NAME ": NatSemi SCx200 Driver\n");
 145
 146         return pci_register_driver(&scx200_pci_driver);
 147 }
 148
 149 static void __exit scx200_cleanup(void)
 150 {
 151         pci_unregister_driver(&scx200_pci_driver);
 152         release_region(scx200_gpio_base, SCx200_GPIO_SIZE);
 153 }
 154
 155 module_init(scx200_init);
 156 module_exit(scx200_cleanup);
 157
 158 EXPORT_SYMBOL(scx200_gpio_base);
 159 EXPORT_SYMBOL(scx200_gpio_shadow);
 160 EXPORT_SYMBOL(scx200_gpio_configure);
 161 EXPORT_SYMBOL(scx200_cb_base);
 162
 163 /*
 164     Local variables:
 165         compile-command: "make -k -C ../../.. SUBDIRS=arch/i386/kernel modules"
 166         c-basic-offset: 8
 167     End:
 168 */