xref: /openbmc/linux/drivers/mtd/maps/sun_uflash.c (revision 95e9fd10)
1 /* sun_uflash.c - Driver for user-programmable flash on
2  *                Sun Microsystems SME boardsets.
3  *
4  * This driver does NOT provide access to the OBP-flash for
5  * safety reasons-- use <linux>/drivers/sbus/char/flash.c instead.
6  *
7  * Copyright (c) 2001 Eric Brower (ebrower@usa.net)
8  */
9 
10 #include <linux/kernel.h>
11 #include <linux/module.h>
12 #include <linux/fs.h>
13 #include <linux/errno.h>
14 #include <linux/init.h>
15 #include <linux/ioport.h>
16 #include <linux/of.h>
17 #include <linux/of_device.h>
18 #include <linux/slab.h>
19 #include <asm/prom.h>
20 #include <asm/uaccess.h>
21 #include <asm/io.h>
22 
23 #include <linux/mtd/mtd.h>
24 #include <linux/mtd/map.h>
25 
26 #define UFLASH_OBPNAME	"flashprom"
27 #define DRIVER_NAME	"sun_uflash"
28 #define PFX		DRIVER_NAME ": "
29 
30 #define UFLASH_WINDOW_SIZE	0x200000
31 #define UFLASH_BUSWIDTH		1			/* EBus is 8-bit */
32 
33 MODULE_AUTHOR("Eric Brower <ebrower@usa.net>");
34 MODULE_DESCRIPTION("User-programmable flash device on Sun Microsystems boardsets");
35 MODULE_SUPPORTED_DEVICE(DRIVER_NAME);
36 MODULE_LICENSE("GPL");
37 MODULE_VERSION("2.1");
38 
39 struct uflash_dev {
40 	const char		*name;	/* device name */
41 	struct map_info 	map;	/* mtd map info */
42 	struct mtd_info		*mtd;	/* mtd info */
43 };
44 
45 struct map_info uflash_map_templ = {
46 	.name =		"SUNW,???-????",
47 	.size =		UFLASH_WINDOW_SIZE,
48 	.bankwidth =	UFLASH_BUSWIDTH,
49 };
50 
51 int uflash_devinit(struct platform_device *op, struct device_node *dp)
52 {
53 	struct uflash_dev *up;
54 
55 	if (op->resource[1].flags) {
56 		/* Non-CFI userflash device-- once I find one we
57 		 * can work on supporting it.
58 		 */
59 		printk(KERN_ERR PFX "Unsupported device at %s, 0x%llx\n",
60 		       dp->full_name, (unsigned long long)op->resource[0].start);
61 
62 		return -ENODEV;
63 	}
64 
65 	up = kzalloc(sizeof(struct uflash_dev), GFP_KERNEL);
66 	if (!up) {
67 		printk(KERN_ERR PFX "Cannot allocate struct uflash_dev\n");
68 		return -ENOMEM;
69 	}
70 
71 	/* copy defaults and tweak parameters */
72 	memcpy(&up->map, &uflash_map_templ, sizeof(uflash_map_templ));
73 
74 	up->map.size = resource_size(&op->resource[0]);
75 
76 	up->name = of_get_property(dp, "model", NULL);
77 	if (up->name && 0 < strlen(up->name))
78 		up->map.name = (char *)up->name;
79 
80 	up->map.phys = op->resource[0].start;
81 
82 	up->map.virt = of_ioremap(&op->resource[0], 0, up->map.size,
83 				  DRIVER_NAME);
84 	if (!up->map.virt) {
85 		printk(KERN_ERR PFX "Failed to map device.\n");
86 		kfree(up);
87 
88 		return -EINVAL;
89 	}
90 
91 	simple_map_init(&up->map);
92 
93 	/* MTD registration */
94 	up->mtd = do_map_probe("cfi_probe", &up->map);
95 	if (!up->mtd) {
96 		of_iounmap(&op->resource[0], up->map.virt, up->map.size);
97 		kfree(up);
98 
99 		return -ENXIO;
100 	}
101 
102 	up->mtd->owner = THIS_MODULE;
103 
104 	mtd_device_register(up->mtd, NULL, 0);
105 
106 	dev_set_drvdata(&op->dev, up);
107 
108 	return 0;
109 }
110 
111 static int __devinit uflash_probe(struct platform_device *op)
112 {
113 	struct device_node *dp = op->dev.of_node;
114 
115 	/* Flashprom must have the "user" property in order to
116 	 * be used by this driver.
117 	 */
118 	if (!of_find_property(dp, "user", NULL))
119 		return -ENODEV;
120 
121 	return uflash_devinit(op, dp);
122 }
123 
124 static int __devexit uflash_remove(struct platform_device *op)
125 {
126 	struct uflash_dev *up = dev_get_drvdata(&op->dev);
127 
128 	if (up->mtd) {
129 		mtd_device_unregister(up->mtd);
130 		map_destroy(up->mtd);
131 	}
132 	if (up->map.virt) {
133 		of_iounmap(&op->resource[0], up->map.virt, up->map.size);
134 		up->map.virt = NULL;
135 	}
136 
137 	kfree(up);
138 
139 	return 0;
140 }
141 
142 static const struct of_device_id uflash_match[] = {
143 	{
144 		.name = UFLASH_OBPNAME,
145 	},
146 	{},
147 };
148 
149 MODULE_DEVICE_TABLE(of, uflash_match);
150 
151 static struct platform_driver uflash_driver = {
152 	.driver = {
153 		.name = DRIVER_NAME,
154 		.owner = THIS_MODULE,
155 		.of_match_table = uflash_match,
156 	},
157 	.probe		= uflash_probe,
158 	.remove		= __devexit_p(uflash_remove),
159 };
160 
161 module_platform_driver(uflash_driver);
162