drivers/mtd/maps/sun_uflash.c

   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/ioport.h>
  15 #include <linux/of.h>
  16 #include <linux/of_device.h>
  17 #include <linux/slab.h>
  18 #include <asm/prom.h>
  19 #include <linux/uaccess.h>
  20 #include <asm/io.h>
  21
  22 #include <linux/mtd/mtd.h>
  23 #include <linux/mtd/map.h>
  24
  25 #define UFLASH_OBPNAME  "flashprom"
  26 #define DRIVER_NAME     "sun_uflash"
  27 #define PFX             DRIVER_NAME ": "
  28
  29 #define UFLASH_WINDOW_SIZE      0x200000
  30 #define UFLASH_BUSWIDTH         1                       /* EBus is 8-bit */
  31
  32 MODULE_AUTHOR("Eric Brower <ebrower@usa.net>");
  33 MODULE_DESCRIPTION("User-programmable flash device on Sun Microsystems boardsets");
  34 MODULE_SUPPORTED_DEVICE(DRIVER_NAME);
  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 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(sizeof(struct uflash_dev), GFP_KERNEL);
  65         if (!up) {
  66                 printk(KERN_ERR PFX "Cannot allocate struct uflash_dev\n");
  67                 return -ENOMEM;
  68         }
  69
  70         /* copy defaults and tweak parameters */
  71         memcpy(&up->map, &uflash_map_templ, sizeof(uflash_map_templ));
  72
  73         up->map.size = resource_size(&op->resource[0]);
  74
  75         up->name = of_get_property(dp, "model", NULL);
  76         if (up->name && 0 < strlen(up->name))
  77                 up->map.name = up->name;
  78
  79         up->map.phys = op->resource[0].start;
  80
  81         up->map.virt = of_ioremap(&op->resource[0], 0, up->map.size,
  82                                   DRIVER_NAME);
  83         if (!up->map.virt) {
  84                 printk(KERN_ERR PFX "Failed to map device.\n");
  85                 kfree(up);
  86
  87                 return -EINVAL;
  88         }
  89
  90         simple_map_init(&up->map);
  91
  92         /* MTD registration */
  93         up->mtd = do_map_probe("cfi_probe", &up->map);
  94         if (!up->mtd) {
  95                 of_iounmap(&op->resource[0], up->map.virt, up->map.size);
  96                 kfree(up);
  97
  98                 return -ENXIO;
  99         }
 100
 101         up->mtd->owner = THIS_MODULE;
 102
 103         mtd_device_register(up->mtd, NULL, 0);
 104
 105         dev_set_drvdata(&op->dev, up);
 106
 107         return 0;
 108 }
 109
 110 static int uflash_probe(struct platform_device *op)
 111 {
 112         struct device_node *dp = op->dev.of_node;
 113
 114         /* Flashprom must have the "user" property in order to
 115          * be used by this driver.
 116          */
 117         if (!of_find_property(dp, "user", NULL))
 118                 return -ENODEV;
 119
 120         return uflash_devinit(op, dp);
 121 }
 122
 123 static int uflash_remove(struct platform_device *op)
 124 {
 125         struct uflash_dev *up = dev_get_drvdata(&op->dev);
 126
 127         if (up->mtd) {
 128                 mtd_device_unregister(up->mtd);
 129                 map_destroy(up->mtd);
 130         }
 131         if (up->map.virt) {
 132                 of_iounmap(&op->resource[0], up->map.virt, up->map.size);
 133                 up->map.virt = NULL;
 134         }
 135
 136         kfree(up);
 137
 138         return 0;
 139 }
 140
 141 static const struct of_device_id uflash_match[] = {
 142         {
 143                 .name = UFLASH_OBPNAME,
 144         },
 145         {},
 146 };
 147
 148 MODULE_DEVICE_TABLE(of, uflash_match);
 149
 150 static struct platform_driver uflash_driver = {
 151         .driver = {
 152                 .name = DRIVER_NAME,
 153                 .of_match_table = uflash_match,
 154         },
 155         .probe          = uflash_probe,
 156         .remove         = uflash_remove,
 157 };
 158
 159 module_platform_driver(uflash_driver);