device tree: reworked and cleaned up

* Moved device tree functions to
  modules/devices/devicetree/dt_util.c
* The dtr_* functions usable from outside devicetree.c,
  for example in get_motherboard().
  Must #include "dt_util.h"
* Now possible to use an alternate device tree root for testing
  -DOVRDTRROOT=\"/some/path\"
* Alternately, pass dtr_new() an alternate base path.
* Abandoned the tuple grouping and inherited properties stuff
  for now.

Signed-off-by: Burt P <pburt0@gmail.com>

1 files changed, 61 insertions, 0 deletions

diff --git a/includes/dt_util.h b/includes/dt_util.h
new file mode 100644
index 00000000..e044def7
--- /dev/null
+++ b/includes/dt_util.h
@@ -0,0 +1,61 @@
+
+#ifndef _DT_UTIL_H_
+#define _DT_UTIL_H_
+
+#include <stdint.h>
+
+/* some not-quite-complete stuff that can be disabled */
+#define DTEX_PHREFS 0
+
+#ifndef DTR_ROOT
+#define DTR_ROOT "/proc/device-tree"
+#endif
+
+enum {
+    DT_TYPE_ERR,
+
+    DT_NODE,
+    DTP_UNK,     /* arbitrary-length byte sequence */
+    DTP_EMPTY,   /* empty property */
+    DTP_STR,     /* null-delimited list of strings */
+    DTP_HEX,     /* list of 32-bit values displayed in hex */
+    DTP_UINT,
+ /* DTP_INT, */
+    DTP_PH,      /* phandle */
+    DTP_PH_REF,  /* reference to phandle */
+};
+
+/* simplest, no aliases.
+ * use dtr_get_prop_str() for complete. */
+char* dtr_get_string(const char *p);
+
+typedef uint32_t dt_uint; /* big-endian */
+
+typedef struct _dtr dtr;
+typedef struct _dtr_obj dtr_obj;
+
+dtr *dtr_new(char *base_path); /* NULL for DTR_ROOT */
+void dtr_free(dtr *);
+const char *dtr_base_path(dtr *);
+
+dtr_obj *dtr_obj_read(dtr *, const char *dtp);
+void dtr_obj_free(dtr_obj *);
+int dtr_obj_type(dtr_obj *);
+char *dtr_obj_alias(dtr_obj *);
+char *dtr_obj_path(dtr_obj *);
+char *dtr_obj_full_path(dtr_obj *);
+
+char* dtr_str(dtr *, dtr_obj *obj);
+dtr_obj *dtr_get_prop_obj(dtr *, dtr_obj *node, const char *name);
+char *dtr_get_prop_str(dtr *, dtr_obj *node, const char *name);
+uint32_t dtr_get_prop_u32(dtr *, dtr_obj *node, const char *name);
+
+static int dtr_guess_type(dtr_obj *obj);
+char *dtr_elem_phref(dtr *, dt_uint e);
+char *dtr_elem_hex(dt_uint e);
+char *dtr_elem_byte(uint8_t e);
+char *dtr_elem_uint(dt_uint e);
+char *dtr_list_byte(uint8_t *bytes, unsigned long count);
+char *dtr_list_hex(dt_uint *list, unsigned long count);
+
+#endif