scx200_32.c

  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
 21MODULE_AUTHOR("Christer Weinigel <wingel@nano-system.com>");
 22MODULE_DESCRIPTION("NatSemi SCx200 Driver");
 23MODULE_LICENSE("GPL");
 24
 25unsigned scx200_gpio_base = 0;
 26unsigned long scx200_gpio_shadow[2];
 27
 28unsigned scx200_cb_base = 0;
 29
 30static 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};
 37MODULE_DEVICE_TABLE(pci,scx200_tbl);
 38
 39static int scx200_probe(struct pci_dev *, const struct pci_device_id *);
 40
 41static struct pci_driver scx200_pci_driver = {
 42	.name = "scx200",
 43	.id_table = scx200_tbl,
 44	.probe = scx200_probe,
 45};
 46
 47static DEFINE_MUTEX(scx200_gpio_config_lock);
 48
 49static 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
 58static 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
 95u32 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
112static int __init scx200_init(void)
113{
114	pr_info("NatSemi SCx200 Driver\n");
115	return pci_register_driver(&scx200_pci_driver);
116}
117
118static void __exit scx200_cleanup(void)
119{
120	pci_unregister_driver(&scx200_pci_driver);
121	release_region(scx200_gpio_base, SCx200_GPIO_SIZE);
122}
123
124module_init(scx200_init);
125module_exit(scx200_cleanup);
126
127EXPORT_SYMBOL(scx200_gpio_base);
128EXPORT_SYMBOL(scx200_gpio_shadow);
129EXPORT_SYMBOL(scx200_gpio_configure);
130EXPORT_SYMBOL(scx200_cb_base);