include/linux/usb/gadget_configfs.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef __GADGET_CONFIGFS__
   3 #define __GADGET_CONFIGFS__
   4
   5 #include <linux/configfs.h>
   6
   7 #define GS_STRINGS_W(__struct, __name)  \
   8 static ssize_t __struct##_##__name##_store(struct config_item *item, \
   9                 const char *page, size_t len)           \
  10 {                                                       \
  11         struct __struct *gs = to_##__struct(item);      \
  12         int ret;                                        \
  13                                                         \
  14         ret = usb_string_copy(page, &gs->__name);       \
  15         if (ret)                                        \
  16                 return ret;                             \
  17         return len;                                     \
  18 }
  19
  20 #define GS_STRINGS_R(__struct, __name)  \
  21 static ssize_t __struct##_##__name##_show(struct config_item *item, char *page) \
  22 {       \
  23         struct __struct *gs = to_##__struct(item);      \
  24         return sprintf(page, "%s\n", gs->__name ?: ""); \
  25 }
  26
  27 #define GS_STRINGS_RW(struct_name, _name)       \
  28         GS_STRINGS_R(struct_name, _name)        \
  29         GS_STRINGS_W(struct_name, _name)        \
  30         CONFIGFS_ATTR(struct_name##_, _name)
  31
  32 #define USB_CONFIG_STRING_RW_OPS(struct_in)                             \
  33 static struct configfs_item_operations struct_in##_langid_item_ops = {  \
  34         .release                = struct_in##_attr_release,             \
  35 };                                                                      \
  36                                                                         \
  37 static const struct config_item_type struct_in##_langid_type = {        \
  38         .ct_item_ops    = &struct_in##_langid_item_ops,                 \
  39         .ct_attrs       = struct_in##_langid_attrs,                     \
  40         .ct_owner       = THIS_MODULE,                                  \
  41 }
  42
  43 #define USB_CONFIG_STRINGS_LANG(struct_in, struct_member)       \
  44         static struct config_group *struct_in##_strings_make(           \
  45                         struct config_group *group,                     \
  46                         const char *name)                               \
  47         {                                                               \
  48         struct struct_member *gi;                                       \
  49         struct struct_in *gs;                                           \
  50         struct struct_in *new;                                          \
  51         int langs = 0;                                                  \
  52         int ret;                                                        \
  53                                                                         \
  54         new = kzalloc(sizeof(*new), GFP_KERNEL);                        \
  55         if (!new)                                                       \
  56                 return ERR_PTR(-ENOMEM);                                \
  57                                                                         \
  58         ret = check_user_usb_string(name, &new->stringtab_dev);         \
  59         if (ret)                                                        \
  60                 goto err;                                               \
  61         config_group_init_type_name(&new->group, name,                  \
  62                         &struct_in##_langid_type);                      \
  63                                                                         \
  64         gi = container_of(group, struct struct_member, strings_group);  \
  65         ret = -EEXIST;                                                  \
  66         list_for_each_entry(gs, &gi->string_list, list) {               \
  67                 if (gs->stringtab_dev.language == new->stringtab_dev.language) \
  68                         goto err;                                       \
  69                 langs++;                                                \
  70         }                                                               \
  71         ret = -EOVERFLOW;                                               \
  72         if (langs >= MAX_USB_STRING_LANGS)                              \
  73                 goto err;                                               \
  74                                                                         \
  75         list_add_tail(&new->list, &gi->string_list);                    \
  76         return &new->group;                                             \
  77 err:                                                                    \
  78         kfree(new);                                                     \
  79         return ERR_PTR(ret);                                            \
  80 }                                                                       \
  81                                                                         \
  82 static void struct_in##_strings_drop(                                   \
  83                 struct config_group *group,                             \
  84                 struct config_item *item)                               \
  85 {                                                                       \
  86         config_item_put(item);                                          \
  87 }                                                                       \
  88                                                                         \
  89 static struct configfs_group_operations struct_in##_strings_ops = {     \
  90         .make_group     = &struct_in##_strings_make,                    \
  91         .drop_item      = &struct_in##_strings_drop,                    \
  92 };                                                                      \
  93                                                                         \
  94 static const struct config_item_type struct_in##_strings_type = {       \
  95         .ct_group_ops   = &struct_in##_strings_ops,                     \
  96         .ct_owner       = THIS_MODULE,                                  \
  97 }
  98
  99 #endif