1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* sun_uflash.c - Driver for user-programmable flash on |
3 | * Sun Microsystems SME boardsets. |
4 | * |
5 | * This driver does NOT provide access to the OBP-flash for |
6 | * safety reasons-- use <linux>/drivers/sbus/char/flash.c instead. |
7 | * |
8 | * Copyright (c) 2001 Eric Brower (ebrower@usa.net) |
9 | */ |
10 | |
11 | #include <linux/kernel.h> |
12 | #include <linux/module.h> |
13 | #include <linux/fs.h> |
14 | #include <linux/errno.h> |
15 | #include <linux/ioport.h> |
16 | #include <linux/of.h> |
17 | #include <linux/platform_device.h> |
18 | #include <linux/slab.h> |
19 | #include <asm/prom.h> |
20 | #include <linux/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_LICENSE("GPL" ); |
36 | MODULE_VERSION("2.1" ); |
37 | |
38 | struct uflash_dev { |
39 | const char *name; /* device name */ |
40 | struct map_info map; /* mtd map info */ |
41 | struct mtd_info *mtd; /* mtd info */ |
42 | }; |
43 | |
44 | struct map_info uflash_map_templ = { |
45 | .name = "SUNW,???-????" , |
46 | .size = UFLASH_WINDOW_SIZE, |
47 | .bankwidth = UFLASH_BUSWIDTH, |
48 | }; |
49 | |
50 | static int uflash_devinit(struct platform_device *op, struct device_node *dp) |
51 | { |
52 | struct uflash_dev *up; |
53 | |
54 | if (op->resource[1].flags) { |
55 | /* Non-CFI userflash device-- once I find one we |
56 | * can work on supporting it. |
57 | */ |
58 | printk(KERN_ERR PFX "Unsupported device at %pOF, 0x%llx\n" , |
59 | dp, (unsigned long long)op->resource[0].start); |
60 | |
61 | return -ENODEV; |
62 | } |
63 | |
64 | up = kzalloc(size: sizeof(struct uflash_dev), GFP_KERNEL); |
65 | if (!up) |
66 | return -ENOMEM; |
67 | |
68 | /* copy defaults and tweak parameters */ |
69 | memcpy(&up->map, &uflash_map_templ, sizeof(uflash_map_templ)); |
70 | |
71 | up->map.size = resource_size(res: &op->resource[0]); |
72 | |
73 | up->name = of_get_property(node: dp, name: "model" , NULL); |
74 | if (up->name && 0 < strlen(up->name)) |
75 | up->map.name = up->name; |
76 | |
77 | up->map.phys = op->resource[0].start; |
78 | |
79 | up->map.virt = of_ioremap(&op->resource[0], 0, up->map.size, |
80 | DRIVER_NAME); |
81 | if (!up->map.virt) { |
82 | printk(KERN_ERR PFX "Failed to map device.\n" ); |
83 | kfree(objp: up); |
84 | |
85 | return -EINVAL; |
86 | } |
87 | |
88 | simple_map_init(&up->map); |
89 | |
90 | /* MTD registration */ |
91 | up->mtd = do_map_probe(name: "cfi_probe" , map: &up->map); |
92 | if (!up->mtd) { |
93 | of_iounmap(&op->resource[0], up->map.virt, up->map.size); |
94 | kfree(objp: up); |
95 | |
96 | return -ENXIO; |
97 | } |
98 | |
99 | up->mtd->owner = THIS_MODULE; |
100 | |
101 | mtd_device_register(up->mtd, NULL, 0); |
102 | |
103 | dev_set_drvdata(dev: &op->dev, data: up); |
104 | |
105 | return 0; |
106 | } |
107 | |
108 | static int uflash_probe(struct platform_device *op) |
109 | { |
110 | struct device_node *dp = op->dev.of_node; |
111 | |
112 | /* Flashprom must have the "user" property in order to |
113 | * be used by this driver. |
114 | */ |
115 | if (!of_property_read_bool(np: dp, propname: "user" )) |
116 | return -ENODEV; |
117 | |
118 | return uflash_devinit(op, dp); |
119 | } |
120 | |
121 | static void uflash_remove(struct platform_device *op) |
122 | { |
123 | struct uflash_dev *up = dev_get_drvdata(dev: &op->dev); |
124 | |
125 | if (up->mtd) { |
126 | mtd_device_unregister(master: up->mtd); |
127 | map_destroy(mtd: up->mtd); |
128 | } |
129 | if (up->map.virt) { |
130 | of_iounmap(&op->resource[0], up->map.virt, up->map.size); |
131 | up->map.virt = NULL; |
132 | } |
133 | |
134 | kfree(objp: up); |
135 | } |
136 | |
137 | static const struct of_device_id uflash_match[] = { |
138 | { |
139 | .name = UFLASH_OBPNAME, |
140 | }, |
141 | {}, |
142 | }; |
143 | |
144 | MODULE_DEVICE_TABLE(of, uflash_match); |
145 | |
146 | static struct platform_driver uflash_driver = { |
147 | .driver = { |
148 | .name = DRIVER_NAME, |
149 | .of_match_table = uflash_match, |
150 | }, |
151 | .probe = uflash_probe, |
152 | .remove_new = uflash_remove, |
153 | }; |
154 | |
155 | module_platform_driver(uflash_driver); |
156 | |