xref: /openbmc/linux/drivers/mtd/maps/sun_uflash.c (revision 64c70b1c)
1 /* $Id: sun_uflash.c,v 1.13 2005/11/07 11:14:28 gleixner Exp $
2  *
3  * sun_uflash - Driver implementation for user-programmable flash
4  * present on many Sun Microsystems SME boardsets.
5  *
6  * This driver does NOT provide access to the OBP-flash for
7  * safety reasons-- use <linux>/drivers/sbus/char/flash.c instead.
8  *
9  * Copyright (c) 2001 Eric Brower (ebrower@usa.net)
10  *
11  */
12 
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/fs.h>
16 #include <linux/errno.h>
17 #include <linux/init.h>
18 #include <linux/ioport.h>
19 #include <asm/ebus.h>
20 #include <asm/oplib.h>
21 #include <asm/prom.h>
22 #include <asm/uaccess.h>
23 #include <asm/io.h>
24 
25 #include <linux/mtd/mtd.h>
26 #include <linux/mtd/map.h>
27 
28 #define UFLASH_OBPNAME	"flashprom"
29 #define UFLASH_DEVNAME 	"userflash"
30 
31 #define UFLASH_WINDOW_SIZE	0x200000
32 #define UFLASH_BUSWIDTH		1			/* EBus is 8-bit */
33 
34 MODULE_AUTHOR("Eric Brower <ebrower@usa.net>");
35 MODULE_DESCRIPTION("User-programmable flash device on Sun Microsystems boardsets");
36 MODULE_SUPPORTED_DEVICE("userflash");
37 MODULE_LICENSE("GPL");
38 MODULE_VERSION("2.0");
39 
40 static LIST_HEAD(device_list);
41 struct uflash_dev {
42 	const char		*name;	/* device name */
43 	struct map_info 	map;	/* mtd map info */
44 	struct mtd_info		*mtd;	/* mtd info */
45 };
46 
47 
48 struct map_info uflash_map_templ = {
49 	.name =		"SUNW,???-????",
50 	.size =		UFLASH_WINDOW_SIZE,
51 	.bankwidth =	UFLASH_BUSWIDTH,
52 };
53 
54 int uflash_devinit(struct linux_ebus_device *edev, struct device_node *dp)
55 {
56 	struct uflash_dev *up;
57 	struct resource *res;
58 
59 	res = &edev->resource[0];
60 
61 	if (edev->num_addrs != 1) {
62 		/* Non-CFI userflash device-- once I find one we
63 		 * can work on supporting it.
64 		 */
65 		printk("%s: unsupported device at 0x%llx (%d regs): " \
66 			"email ebrower@usa.net\n",
67 		       dp->full_name, (unsigned long long)res->start,
68 		       edev->num_addrs);
69 
70 		return -ENODEV;
71 	}
72 
73 	up = kzalloc(sizeof(struct uflash_dev), GFP_KERNEL);
74 	if (!up)
75 		return -ENOMEM;
76 
77 	/* copy defaults and tweak parameters */
78 	memcpy(&up->map, &uflash_map_templ, sizeof(uflash_map_templ));
79 	up->map.size = (res->end - res->start) + 1UL;
80 
81 	up->name = of_get_property(dp, "model", NULL);
82 	if (up->name && 0 < strlen(up->name))
83 		up->map.name = (char *)up->name;
84 
85 	up->map.phys = res->start;
86 
87 	up->map.virt = ioremap_nocache(res->start, up->map.size);
88 	if (!up->map.virt) {
89 		printk("%s: Failed to map device.\n", dp->full_name);
90 		kfree(up);
91 
92 		return -EINVAL;
93 	}
94 
95 	simple_map_init(&up->map);
96 
97 	/* MTD registration */
98 	up->mtd = do_map_probe("cfi_probe", &up->map);
99 	if (!up->mtd) {
100 		iounmap(up->map.virt);
101 		kfree(up);
102 
103 		return -ENXIO;
104 	}
105 
106 	up->mtd->owner = THIS_MODULE;
107 
108 	add_mtd_device(up->mtd);
109 
110 	dev_set_drvdata(&edev->ofdev.dev, up);
111 
112 	return 0;
113 }
114 
115 static int __devinit uflash_probe(struct of_device *dev, const struct of_device_id *match)
116 {
117 	struct linux_ebus_device *edev = to_ebus_device(&dev->dev);
118 	struct device_node *dp = dev->node;
119 
120 	if (of_find_property(dp, "user", NULL))
121 		return -ENODEV;
122 
123 	return uflash_devinit(edev, dp);
124 }
125 
126 static int __devexit uflash_remove(struct of_device *dev)
127 {
128 	struct uflash_dev *up = dev_get_drvdata(&dev->dev);
129 
130 	if (up->mtd) {
131 		del_mtd_device(up->mtd);
132 		map_destroy(up->mtd);
133 	}
134 	if (up->map.virt) {
135 		iounmap(up->map.virt);
136 		up->map.virt = NULL;
137 	}
138 
139 	kfree(up);
140 
141 	return 0;
142 }
143 
144 static struct of_device_id uflash_match[] = {
145 	{
146 		.name = UFLASH_OBPNAME,
147 	},
148 	{},
149 };
150 
151 MODULE_DEVICE_TABLE(of, uflash_match);
152 
153 static struct of_platform_driver uflash_driver = {
154 	.name		= UFLASH_DEVNAME,
155 	.match_table	= uflash_match,
156 	.probe		= uflash_probe,
157 	.remove		= __devexit_p(uflash_remove),
158 };
159 
160 static int __init uflash_init(void)
161 {
162 	return of_register_driver(&uflash_driver, &ebus_bus_type);
163 }
164 
165 static void __exit uflash_exit(void)
166 {
167 	of_unregister_driver(&uflash_driver);
168 }
169 
170 module_init(uflash_init);
171 module_exit(uflash_exit);
172