Merge http://ftp.arm.linux.org.uk/pub/linux/arm/kernel/git-cur/linux-2.6-arm into...
[linux-2.6] / drivers / mtd / maps / bfin-async-flash.c
1 /*
2  * drivers/mtd/maps/bfin-async-flash.c
3  *
4  * Handle the case where flash memory and ethernet mac/phy are
5  * mapped onto the same async bank.  The BF533-STAMP does this
6  * for example.  All board-specific configuration goes in your
7  * board resources file.
8  *
9  * Copyright 2000 Nicolas Pitre <nico@cam.org>
10  * Copyright 2005-2008 Analog Devices Inc.
11  *
12  * Enter bugs at http://blackfin.uclinux.org/
13  *
14  * Licensed under the GPL-2 or later.
15  */
16
17 #include <linux/init.h>
18 #include <linux/kernel.h>
19 #include <linux/module.h>
20 #include <linux/mtd/mtd.h>
21 #include <linux/mtd/map.h>
22 #include <linux/mtd/partitions.h>
23 #include <linux/mtd/physmap.h>
24 #include <linux/platform_device.h>
25 #include <linux/types.h>
26
27 #include <asm/blackfin.h>
28 #include <linux/gpio.h>
29 #include <linux/io.h>
30 #include <asm/unaligned.h>
31
32 #define pr_devinit(fmt, args...) ({ static const __devinitconst char __fmt[] = fmt; printk(__fmt, ## args); })
33
34 #define DRIVER_NAME "bfin-async-flash"
35
36 struct async_state {
37         struct mtd_info *mtd;
38         struct map_info map;
39         int enet_flash_pin;
40         uint32_t flash_ambctl0, flash_ambctl1;
41         uint32_t save_ambctl0, save_ambctl1;
42         unsigned long irq_flags;
43 };
44
45 static void switch_to_flash(struct async_state *state)
46 {
47         local_irq_save(state->irq_flags);
48
49         gpio_set_value(state->enet_flash_pin, 0);
50
51         state->save_ambctl0 = bfin_read_EBIU_AMBCTL0();
52         state->save_ambctl1 = bfin_read_EBIU_AMBCTL1();
53         bfin_write_EBIU_AMBCTL0(state->flash_ambctl0);
54         bfin_write_EBIU_AMBCTL1(state->flash_ambctl1);
55         SSYNC();
56 }
57
58 static void switch_back(struct async_state *state)
59 {
60         bfin_write_EBIU_AMBCTL0(state->save_ambctl0);
61         bfin_write_EBIU_AMBCTL1(state->save_ambctl1);
62         SSYNC();
63
64         gpio_set_value(state->enet_flash_pin, 1);
65
66         local_irq_restore(state->irq_flags);
67 }
68
69 static map_word bfin_read(struct map_info *map, unsigned long ofs)
70 {
71         struct async_state *state = (struct async_state *)map->map_priv_1;
72         uint16_t word;
73         map_word test;
74
75         switch_to_flash(state);
76
77         word = readw(map->virt + ofs);
78
79         switch_back(state);
80
81         test.x[0] = word;
82         return test;
83 }
84
85 static void bfin_copy_from(struct map_info *map, void *to, unsigned long from, ssize_t len)
86 {
87         struct async_state *state = (struct async_state *)map->map_priv_1;
88
89         switch_to_flash(state);
90
91         memcpy(to, map->virt + from, len);
92
93         switch_back(state);
94 }
95
96 static void bfin_write(struct map_info *map, map_word d1, unsigned long ofs)
97 {
98         struct async_state *state = (struct async_state *)map->map_priv_1;
99         uint16_t d;
100
101         d = d1.x[0];
102
103         switch_to_flash(state);
104
105         writew(d, map->virt + ofs);
106         SSYNC();
107
108         switch_back(state);
109 }
110
111 static void bfin_copy_to(struct map_info *map, unsigned long to, const void *from, ssize_t len)
112 {
113         struct async_state *state = (struct async_state *)map->map_priv_1;
114
115         switch_to_flash(state);
116
117         memcpy(map->virt + to, from, len);
118         SSYNC();
119
120         switch_back(state);
121 }
122
123 #ifdef CONFIG_MTD_PARTITIONS
124 static const char *part_probe_types[] = { "cmdlinepart", "RedBoot", NULL };
125 #endif
126
127 static int __devinit bfin_flash_probe(struct platform_device *pdev)
128 {
129         int ret;
130         struct physmap_flash_data *pdata = pdev->dev.platform_data;
131         struct resource *memory = platform_get_resource(pdev, IORESOURCE_MEM, 0);
132         struct resource *flash_ambctl = platform_get_resource(pdev, IORESOURCE_MEM, 1);
133         struct async_state *state;
134
135         state = kzalloc(sizeof(*state), GFP_KERNEL);
136         if (!state)
137                 return -ENOMEM;
138
139         state->map.name       = DRIVER_NAME;
140         state->map.read       = bfin_read;
141         state->map.copy_from  = bfin_copy_from;
142         state->map.write      = bfin_write;
143         state->map.copy_to    = bfin_copy_to;
144         state->map.bankwidth  = pdata->width;
145         state->map.size       = memory->end - memory->start + 1;
146         state->map.virt       = (void __iomem *)memory->start;
147         state->map.phys       = memory->start;
148         state->map.map_priv_1 = (unsigned long)state;
149         state->enet_flash_pin = platform_get_irq(pdev, 0);
150         state->flash_ambctl0  = flash_ambctl->start;
151         state->flash_ambctl1  = flash_ambctl->end;
152
153         if (gpio_request(state->enet_flash_pin, DRIVER_NAME)) {
154                 pr_devinit(KERN_ERR DRIVER_NAME ": Failed to request gpio %d\n", state->enet_flash_pin);
155                 return -EBUSY;
156         }
157         gpio_direction_output(state->enet_flash_pin, 1);
158
159         pr_devinit(KERN_NOTICE DRIVER_NAME ": probing %d-bit flash bus\n", state->map.bankwidth * 8);
160         state->mtd = do_map_probe(memory->name, &state->map);
161         if (!state->mtd)
162                 return -ENXIO;
163
164 #ifdef CONFIG_MTD_PARTITIONS
165         ret = parse_mtd_partitions(state->mtd, part_probe_types, &pdata->parts, 0);
166         if (ret > 0) {
167                 pr_devinit(KERN_NOTICE DRIVER_NAME ": Using commandline partition definition\n");
168                 add_mtd_partitions(state->mtd, pdata->parts, ret);
169
170         } else if (pdata->nr_parts) {
171                 pr_devinit(KERN_NOTICE DRIVER_NAME ": Using board partition definition\n");
172                 add_mtd_partitions(state->mtd, pdata->parts, pdata->nr_parts);
173
174         } else
175 #endif
176         {
177                 pr_devinit(KERN_NOTICE DRIVER_NAME ": no partition info available, registering whole flash at once\n");
178                 add_mtd_device(state->mtd);
179         }
180
181         platform_set_drvdata(pdev, state);
182
183         return 0;
184 }
185
186 static int __devexit bfin_flash_remove(struct platform_device *pdev)
187 {
188         struct async_state *state = platform_get_drvdata(pdev);
189         gpio_free(state->enet_flash_pin);
190 #ifdef CONFIG_MTD_PARTITIONS
191         del_mtd_partitions(state->mtd);
192 #endif
193         map_destroy(state->mtd);
194         kfree(state);
195         return 0;
196 }
197
198 static struct platform_driver bfin_flash_driver = {
199         .probe          = bfin_flash_probe,
200         .remove         = __devexit_p(bfin_flash_remove),
201         .driver         = {
202                 .name   = DRIVER_NAME,
203         },
204 };
205
206 static int __init bfin_flash_init(void)
207 {
208         return platform_driver_register(&bfin_flash_driver);
209 }
210 module_init(bfin_flash_init);
211
212 static void __exit bfin_flash_exit(void)
213 {
214         platform_driver_unregister(&bfin_flash_driver);
215 }
216 module_exit(bfin_flash_exit);
217
218 MODULE_LICENSE("GPL");
219 MODULE_DESCRIPTION("MTD map driver for Blackfins with flash/ethernet on same async bank");