arch/powerpc/kernel/of_device.c

   1 #include <linux/string.h>
   2 #include <linux/kernel.h>
   3 #include <linux/of.h>
   4 #include <linux/init.h>
   5 #include <linux/module.h>
   6 #include <linux/mod_devicetable.h>
   7 #include <linux/slab.h>
   8
   9 #include <asm/errno.h>
  10 #include <asm/of_device.h>
  11
  12 ssize_t of_device_get_modalias(struct of_device *ofdev,
  13                                 char *str, ssize_t len)
  14 {
  15         const char *compat;
  16         int cplen, i;
  17         ssize_t tsize, csize, repend;
  18
  19         /* Name & Type */
  20         csize = snprintf(str, len, "of:N%sT%s",
  21                                 ofdev->node->name, ofdev->node->type);
  22
  23         /* Get compatible property if any */
  24         compat = of_get_property(ofdev->node, "compatible", &cplen);
  25         if (!compat)
  26                 return csize;
  27
  28         /* Find true end (we tolerate multiple \0 at the end */
  29         for (i=(cplen-1); i>=0 && !compat[i]; i--)
  30                 cplen--;
  31         if (!cplen)
  32                 return csize;
  33         cplen++;
  34
  35         /* Check space (need cplen+1 chars including final \0) */
  36         tsize = csize + cplen;
  37         repend = tsize;
  38
  39         if (csize>=len)         /* @ the limit, all is already filled */
  40                 return tsize;
  41
  42         if (tsize>=len) {               /* limit compat list */
  43                 cplen = len-csize-1;
  44                 repend = len;
  45         }
  46
  47         /* Copy and do char replacement */
  48         memcpy(&str[csize+1], compat, cplen);
  49         for (i=csize; i<repend; i++) {
  50                 char c = str[i];
  51                 if (c=='\0')
  52                         str[i] = 'C';
  53                 else if (c==' ')
  54                         str[i] = '_';
  55         }
  56
  57         return tsize;
  58 }
  59
  60 int of_device_uevent(struct device *dev,
  61                 char **envp, int num_envp, char *buffer, int buffer_size)
  62 {
  63         struct of_device *ofdev;
  64         const char *compat;
  65         int i = 0, length = 0, seen = 0, cplen, sl;
  66
  67         if (!dev)
  68                 return -ENODEV;
  69
  70         ofdev = to_of_device(dev);
  71
  72         if (add_uevent_var(envp, num_envp, &i,
  73                            buffer, buffer_size, &length,
  74                            "OF_NAME=%s", ofdev->node->name))
  75                 return -ENOMEM;
  76
  77         if (add_uevent_var(envp, num_envp, &i,
  78                            buffer, buffer_size, &length,
  79                            "OF_TYPE=%s", ofdev->node->type))
  80                 return -ENOMEM;
  81
  82         /* Since the compatible field can contain pretty much anything
  83          * it's not really legal to split it out with commas. We split it
  84          * up using a number of environment variables instead. */
  85
  86         compat = of_get_property(ofdev->node, "compatible", &cplen);
  87         while (compat && *compat && cplen > 0) {
  88                 if (add_uevent_var(envp, num_envp, &i,
  89                                    buffer, buffer_size, &length,
  90                                    "OF_COMPATIBLE_%d=%s", seen, compat))
  91                         return -ENOMEM;
  92
  93                 sl = strlen (compat) + 1;
  94                 compat += sl;
  95                 cplen -= sl;
  96                 seen++;
  97         }
  98
  99         if (add_uevent_var(envp, num_envp, &i,
 100                            buffer, buffer_size, &length,
 101                            "OF_COMPATIBLE_N=%d", seen))
 102                 return -ENOMEM;
 103
 104         /* modalias is trickier, we add it in 2 steps */
 105         if (add_uevent_var(envp, num_envp, &i,
 106                            buffer, buffer_size, &length,
 107                            "MODALIAS="))
 108                 return -ENOMEM;
 109
 110         sl = of_device_get_modalias(ofdev, &buffer[length-1],
 111                                         buffer_size-length);
 112         if (sl >= (buffer_size-length))
 113                 return -ENOMEM;
 114
 115         length += sl;
 116
 117         envp[i] = NULL;
 118
 119         return 0;
 120 }
 121 EXPORT_SYMBOL(of_device_uevent);
 122 EXPORT_SYMBOL(of_device_get_modalias);