target/linux/ar71xx/files/drivers/mtd/maps/ar91xx_flash.c

   1 /*
   2  * Parallel flash driver for the Atheros AR91xx SoC
   3  *
   4  * Copyright (C) 2009 Gabor Juhos <juhosg@openwrt.org>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  *
  10  */
  11
  12 #include <linux/module.h>
  13 #include <linux/types.h>
  14 #include <linux/kernel.h>
  15 #include <linux/init.h>
  16 #include <linux/slab.h>
  17 #include <linux/device.h>
  18 #include <linux/platform_device.h>
  19 #include <linux/mtd/mtd.h>
  20 #include <linux/mtd/map.h>
  21 #include <linux/mtd/partitions.h>
  22 #include <linux/io.h>
  23
  24 #include <asm/mach-ar71xx/ar71xx.h>
  25 #include <asm/mach-ar71xx/platform.h>
  26
  27 #define DRV_NAME        "ar91xx-flash"
  28
  29 struct ar91xx_flash_info {
  30         struct mtd_info         *mtd;
  31         struct map_info         map;
  32 #ifdef CONFIG_MTD_PARTITIONS
  33         int                     nr_parts;
  34         struct mtd_partition    *parts;
  35 #endif
  36 };
  37
  38 static map_word ar91xx_flash_read(struct map_info *map, unsigned long ofs)
  39 {
  40         map_word val;
  41
  42         if (map_bankwidth_is_1(map))
  43                 val.x[0] = __raw_readb(map->virt + (ofs ^ 3));
  44         else if (map_bankwidth_is_2(map))
  45                 val.x[0] = __raw_readw(map->virt + (ofs ^ 2));
  46         else
  47                 val = map_word_ff(map);
  48
  49         return val;
  50 }
  51
  52 static void ar91xx_flash_write(struct map_info *map, map_word d,
  53                                unsigned long ofs)
  54 {
  55         if (map_bankwidth_is_1(map))
  56                 __raw_writeb(d.x[0], map->virt + (ofs ^ 3));
  57         else if (map_bankwidth_is_2(map))
  58                 __raw_writew(d.x[0], map->virt + (ofs ^ 2));
  59
  60         mb();
  61 }
  62
  63 static int ar91xx_flash_remove(struct platform_device *pdev)
  64 {
  65         struct ar91xx_flash_platform_data *pdata;
  66         struct ar91xx_flash_info *info;
  67
  68         info = platform_get_drvdata(pdev);
  69         if (info == NULL)
  70                 return 0;
  71
  72         platform_set_drvdata(pdev, NULL);
  73
  74         if (info->mtd == NULL)
  75                 return 0;
  76
  77         pdata = pdev->dev.platform_data;
  78 #ifdef CONFIG_MTD_PARTITIONS
  79         if (info->nr_parts) {
  80                 del_mtd_partitions(info->mtd);
  81                 kfree(info->parts);
  82         } else if (pdata->nr_parts) {
  83                 del_mtd_partitions(info->mtd);
  84         } else {
  85                 del_mtd_device(info->mtd);
  86         }
  87 #else
  88         del_mtd_device(info->mtd);
  89 #endif
  90         map_destroy(info->mtd);
  91
  92         return 0;
  93 }
  94
  95 static const char *rom_probe_types[] = { "cfi_probe", "jedec_probe", NULL };
  96 #ifdef CONFIG_MTD_PARTITIONS
  97 static const char *part_probe_types[] = { "cmdlinepart", "RedBoot", NULL };
  98 #endif
  99
 100 static int ar91xx_flash_probe(struct platform_device *pdev)
 101 {
 102         struct ar91xx_flash_platform_data *pdata;
 103         struct ar91xx_flash_info *info;
 104         struct resource *res;
 105         struct resource *region;
 106         const char **probe_type;
 107         int err = 0;
 108
 109         pdata = pdev->dev.platform_data;
 110         if (pdata == NULL)
 111                 return -EINVAL;
 112
 113         info = devm_kzalloc(&pdev->dev, sizeof(struct ar91xx_flash_info),
 114                             GFP_KERNEL);
 115         if (info == NULL) {
 116                 err = -ENOMEM;
 117                 goto err_out;
 118         }
 119
 120         platform_set_drvdata(pdev, info);
 121
 122         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 123         if (res == NULL) {
 124                 err = -ENOENT;
 125                 goto err_out;
 126         }
 127
 128         dev_info(&pdev->dev, "%.8llx at %.8llx\n",
 129                  (unsigned long long)(res->end - res->start + 1),
 130                  (unsigned long long)res->start);
 131
 132         region = devm_request_mem_region(&pdev->dev,
 133                                          res->start, res->end - res->start + 1,
 134                                          dev_name(&pdev->dev));
 135         if (region == NULL) {
 136                 dev_err(&pdev->dev, "could not reserve memory region\n");
 137                 err = -ENOMEM;
 138                 goto err_out;
 139         }
 140
 141         info->map.name = dev_name(&pdev->dev);
 142         info->map.phys = res->start;
 143         info->map.size = res->end - res->start + 1;
 144         info->map.bankwidth = pdata->width;
 145
 146         info->map.virt = devm_ioremap(&pdev->dev, info->map.phys,
 147                                       info->map.size);
 148         if (info->map.virt == NULL) {
 149                 dev_err(&pdev->dev, "failed to ioremap flash region\n");
 150                 err = -EIO;
 151                 goto err_out;
 152         }
 153
 154         simple_map_init(&info->map);
 155         info->map.read = ar91xx_flash_read;
 156         info->map.write = ar91xx_flash_write;
 157
 158         probe_type = rom_probe_types;
 159         for (; info->mtd == NULL && *probe_type != NULL; probe_type++)
 160                 info->mtd = do_map_probe(*probe_type, &info->map);
 161
 162         if (info->mtd == NULL) {
 163                 dev_err(&pdev->dev, "map_probe failed\n");
 164                 err = -ENXIO;
 165                 goto err_out;
 166         }
 167
 168         info->mtd->owner = THIS_MODULE;
 169
 170 #ifdef CONFIG_MTD_PARTITIONS
 171         if (pdata->nr_parts) {
 172                 dev_info(&pdev->dev, "using static partition mapping\n");
 173                 add_mtd_partitions(info->mtd, pdata->parts, pdata->nr_parts);
 174                 return 0;
 175         }
 176
 177         err = parse_mtd_partitions(info->mtd, part_probe_types,
 178                                    &info->parts, 0);
 179         if (err > 0) {
 180                 add_mtd_partitions(info->mtd, info->parts, err);
 181                 return 0;
 182         }
 183 #endif
 184
 185         add_mtd_device(info->mtd);
 186         return 0;
 187
 188  err_out:
 189         ar91xx_flash_remove(pdev);
 190         return err;
 191 }
 192
 193 #ifdef CONFIG_PM
 194 static int ar91xx_flash_suspend(struct platform_device *dev, pm_message_t state)
 195 {
 196         struct ar91xx_flash_info *info = platform_get_drvdata(dev);
 197         int ret = 0;
 198
 199         if (info->mtd->suspend)
 200                 ret = info->mtd->suspend(info->mtd);
 201
 202         if (ret)
 203                 goto fail;
 204
 205         return 0;
 206
 207  fail:
 208         if (info->mtd->suspend) {
 209                 BUG_ON(!info->mtd->resume);
 210                 info->mtd->resume(info->mtd);
 211         }
 212
 213         return ret;
 214 }
 215
 216 static int ar91xx_flash_resume(struct platform_device *pdev)
 217 {
 218         struct ar91xx_flash_info *info = platform_get_drvdata(pdev);
 219
 220         if (info->mtd->resume)
 221                 info->mtd->resume(info->mtd);
 222
 223         return 0;
 224 }
 225
 226 static void ar91xx_flash_shutdown(struct platform_device *pdev)
 227 {
 228         struct ar91xx_flash_info *info = platform_get_drvdata(pdev);
 229
 230         if (info->mtd->suspend && info->mtd->resume)
 231                 if (info->mtd->suspend(info->mtd) == 0)
 232                         info->mtd->resume(info->mtd);
 233 }
 234 #else
 235 #define ar91xx_flash_suspend    NULL
 236 #define ar91xx_flash_resume     NULL
 237 #define ar91xx_flash_shutdown   NULL
 238 #endif
 239
 240 static struct platform_driver ar91xx_flash_driver = {
 241         .probe          = ar91xx_flash_probe,
 242         .remove         = ar91xx_flash_remove,
 243         .suspend        = ar91xx_flash_suspend,
 244         .resume         = ar91xx_flash_resume,
 245         .shutdown       = ar91xx_flash_shutdown,
 246         .driver         = {
 247                 .name   = DRV_NAME,
 248                 .owner  = THIS_MODULE,
 249         },
 250 };
 251
 252 static int __init ar91xx_flash_init(void)
 253 {
 254         return platform_driver_register(&ar91xx_flash_driver);
 255 }
 256
 257 static void __exit ar91xx_flash_exit(void)
 258 {
 259         platform_driver_unregister(&ar91xx_flash_driver);
 260 }
 261
 262 module_init(ar91xx_flash_init);
 263 module_exit(ar91xx_flash_exit);
 264
 265 MODULE_LICENSE("GPL v2");
 266 MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");
 267 MODULE_DESCRIPTION("Parallel flash driver for the Atheros AR91xx SoC");
 268 MODULE_ALIAS("platform:" DRV_NAME);