kernel/arch/x86/platform/scx200/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 MODULE_AUTHOR("Christer Weinigel <wingel@nano-system.com>");
  21 MODULE_DESCRIPTION("NatSemi SCx200 Driver");
  22 MODULE_LICENSE("GPL");
  23
  24 unsigned scx200_gpio_base = 0;
  25 unsigned long scx200_gpio_shadow[2];
  26
  27 unsigned scx200_cb_base = 0;
  28
  29 static struct pci_device_id scx200_tbl[] = {
  30         { PCI_VDEVICE(NS, PCI_DEVICE_ID_NS_SCx200_BRIDGE) },
  31         { PCI_VDEVICE(NS, PCI_DEVICE_ID_NS_SC1100_BRIDGE) },
  32         { PCI_VDEVICE(NS, PCI_DEVICE_ID_NS_SCx200_XBUS)   },
  33         { PCI_VDEVICE(NS, PCI_DEVICE_ID_NS_SC1100_XBUS)   },
  34         { },
  35 };
  36 MODULE_DEVICE_TABLE(pci,scx200_tbl);
  37
  38 static int scx200_probe(struct pci_dev *, const struct pci_device_id *);
  39
  40 static struct pci_driver scx200_pci_driver = {
  41         .name = "scx200",
  42         .id_table = scx200_tbl,
  43         .probe = scx200_probe,
  44 };
  45
  46 static DEFINE_MUTEX(scx200_gpio_config_lock);
  47
  48 static void scx200_init_shadow(void)
  49 {
  50         int bank;
  51
  52         /* read the current values driven on the GPIO signals */
  53         for (bank = 0; bank < 2; ++bank)
  54                 scx200_gpio_shadow[bank] = inl(scx200_gpio_base + 0x10 * bank);
  55 }
  56
  57 static int scx200_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
  58 {
  59         unsigned base;
  60
  61         if (pdev->device == PCI_DEVICE_ID_NS_SCx200_BRIDGE ||
  62             pdev->device == PCI_DEVICE_ID_NS_SC1100_BRIDGE) {
  63                 base = pci_resource_start(pdev, 0);
  64                 pr_info("GPIO base 0x%x\n", base);
  65
  66                 if (!request_region(base, SCx200_GPIO_SIZE,
  67                                     "NatSemi SCx200 GPIO")) {
  68                         pr_err("can't allocate I/O for GPIOs\n");
  69                         return -EBUSY;
  70                 }
  71
  72                 scx200_gpio_base = base;
  73                 scx200_init_shadow();
  74
  75         } else {
  76                 /* find the base of the Configuration Block */
  77                 if (scx200_cb_probe(SCx200_CB_BASE_FIXED)) {
  78                         scx200_cb_base = SCx200_CB_BASE_FIXED;
  79                 } else {
  80                         pci_read_config_dword(pdev, SCx200_CBA_SCRATCH, &base);
  81                         if (scx200_cb_probe(base)) {
  82                                 scx200_cb_base = base;
  83                         } else {
  84                                 pr_warn("Configuration Block not found\n");
  85                                 return -ENODEV;
  86                         }
  87                 }
  88                 pr_info("Configuration Block base 0x%x\n", scx200_cb_base);
  89         }
  90
  91         return 0;
  92 }
  93
  94 u32 scx200_gpio_configure(unsigned index, u32 mask, u32 bits)
  95 {
  96         u32 config, new_config;
  97
  98         mutex_lock(&scx200_gpio_config_lock);
  99
 100         outl(index, scx200_gpio_base + 0x20);
 101         config = inl(scx200_gpio_base + 0x24);
 102
 103         new_config = (config & mask) | bits;
 104         outl(new_config, scx200_gpio_base + 0x24);
 105
 106         mutex_unlock(&scx200_gpio_config_lock);
 107
 108         return config;
 109 }
 110
 111 static int __init scx200_init(void)
 112 {
 113         pr_info("NatSemi SCx200 Driver\n");
 114         return pci_register_driver(&scx200_pci_driver);
 115 }
 116
 117 static void __exit scx200_cleanup(void)
 118 {
 119         pci_unregister_driver(&scx200_pci_driver);
 120         release_region(scx200_gpio_base, SCx200_GPIO_SIZE);
 121 }
 122
 123 module_init(scx200_init);
 124 module_exit(scx200_cleanup);
 125
 126 EXPORT_SYMBOL(scx200_gpio_base);
 127 EXPORT_SYMBOL(scx200_gpio_shadow);
 128 EXPORT_SYMBOL(scx200_gpio_configure);
 129 EXPORT_SYMBOL(scx200_cb_base);