1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (c) 2001,2002 Christer Weinigel <wingel@nano-system.com>
4 *
5 * National Semiconductor SCx200 support.
6 */
7
8 #include <linux/module.h>
9 #include <linux/errno.h>
10 #include <linux/kernel.h>
11 #include <linux/init.h>
12 #include <linux/mutex.h>
13 #include <linux/pci.h>
14
15 #include <linux/scx200.h>
16 #include <linux/scx200_gpio.h>
17
18 /* Verify that the configuration block really is there */
19 #define scx200_cb_probe(base) (inw((base) + SCx200_CBA) == (base))
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 unsigned long scx200_gpio_shadow[2];
27
28 unsigned scx200_cb_base = 0;
29
30 static struct pci_device_id scx200_tbl[] = {
31 { PCI_VDEVICE(NS, PCI_DEVICE_ID_NS_SCx200_BRIDGE) },
32 { PCI_VDEVICE(NS, PCI_DEVICE_ID_NS_SC1100_BRIDGE) },
33 { PCI_VDEVICE(NS, PCI_DEVICE_ID_NS_SCx200_XBUS) },
34 { PCI_VDEVICE(NS, PCI_DEVICE_ID_NS_SC1100_XBUS) },
35 { },
36 };
37 MODULE_DEVICE_TABLE(pci,scx200_tbl);
38
39 static int 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_MUTEX(scx200_gpio_config_lock);
48
49 static void scx200_init_shadow(void)
50 {
51 int bank;
52
53 /* read the current values driven on the GPIO signals */
54 for (bank = 0; bank < 2; ++bank)
55 scx200_gpio_shadow[bank] = inl(scx200_gpio_base + 0x10 * bank);
56 }
57
58 static int scx200_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
59 {
60 unsigned base;
61
62 if (pdev->device == PCI_DEVICE_ID_NS_SCx200_BRIDGE ||
63 pdev->device == PCI_DEVICE_ID_NS_SC1100_BRIDGE) {
64 base = pci_resource_start(pdev, 0);
65 pr_info("GPIO base 0x%x\n", base);
66
67 if (!request_region(base, SCx200_GPIO_SIZE,
68 "NatSemi SCx200 GPIO")) {
69 pr_err("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 pci_read_config_dword(pdev, SCx200_CBA_SCRATCH, &base);
82 if (scx200_cb_probe(base)) {
83 scx200_cb_base = base;
84 } else {
85 pr_warn("Configuration Block not found\n");
86 return -ENODEV;
87 }
88 }
89 pr_info("Configuration Block base 0x%x\n", scx200_cb_base);
90 }
91
92 return 0;
93 }
94
95 u32 scx200_gpio_configure(unsigned index, u32 mask, u32 bits)
96 {
97 u32 config, new_config;
98
99 mutex_lock(&scx200_gpio_config_lock);
100
101 outl(index, scx200_gpio_base + 0x20);
102 config = inl(scx200_gpio_base + 0x24);
103
104 new_config = (config & mask) | bits;
105 outl(new_config, scx200_gpio_base + 0x24);
106
107 mutex_unlock(&scx200_gpio_config_lock);
108
109 return config;
110 }
111
112 static int __init scx200_init(void)
113 {
114 pr_info("NatSemi SCx200 Driver\n");
115 return pci_register_driver(&scx200_pci_driver);
116 }
117
118 static void __exit scx200_cleanup(void)
119 {
120 pci_unregister_driver(&scx200_pci_driver);
121 release_region(scx200_gpio_base, SCx200_GPIO_SIZE);
122 }
123
124 module_init(scx200_init);
125 module_exit(scx200_cleanup);
126
127 EXPORT_SYMBOL(scx200_gpio_base);
128 EXPORT_SYMBOL(scx200_gpio_shadow);
129 EXPORT_SYMBOL(scx200_gpio_configure);
130 EXPORT_SYMBOL(scx200_cb_base);
131
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