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);
130