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, 569 insertions, 0 deletions

diff --git a/modules/devices/devicetree/dt_util.c b/modules/devices/devicetree/dt_util.c
new file mode 100644
index 00000000..7c713c4f
--- /dev/null
+++ b/modules/devices/devicetree/dt_util.c
@@ -0,0 +1,569 @@
+/*
+ *    HardInfo - Displays System Information
+ *    Copyright (C) 2003-2007 Leandro A. F. Pereira <leandro@hardinfo.org>
+ *
+ *    This program is free software; you can redistribute it and/or modify
+ *    it under the terms of the GNU General Public License as published by
+ *    the Free Software Foundation, version 2.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    GNU General Public License for more details.
+ *
+ *    You should have received a copy of the GNU General Public License
+ *    along with this program; if not, write to the Free Software
+ *    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
+ */
+/*
+ * Device Tree support by Burt P. <pburt0@gmail.com>
+ * Sources:
+ *   http://elinux.org/Device_Tree_Usage
+ *   http://elinux.org/Device_Tree_Mysteries
+ */
+#include <unistd.h>
+#include <sys/types.h>
+#include <endian.h>
+#include "hardinfo.h"
+#include "dt_util.h"
+
+static struct {
+    char *name; int type;
+} prop_types[] = {
+    { "name", DTP_STR },
+    { "compatible", DTP_STR },
+    { "model", DTP_STR },
+    { "reg", DTP_HEX },
+    { "clocks", DTP_HEX },
+    { "gpios", DTP_HEX },
+    { "phandle", DTP_PH },
+    { "interrupts", DTP_HEX },
+    { "interrupt-parent", DTP_PH_REF },
+    { "regulator-min-microvolt", DTP_UINT },
+    { "regulator-max-microvolt", DTP_UINT },
+    { "clock-frequency", DTP_UINT },
+    { NULL, 0 },
+};
+
+struct _dtr_map {
+    uint32_t v;  /* phandle */
+    char *label;  /* alias */
+    char *path;
+    struct _dtr_map *next;
+};
+typedef struct _dtr_map dtr_map;
+
+struct _dtr {
+    dtr_map *aliases;
+    dtr_map *phandles;
+    char *base_path;
+};
+
+struct _dtr_obj {
+    char *path;
+    union {
+        void *data;
+        char *data_str;
+        dt_uint *data_int;
+    };
+    char *name;
+    uint32_t length;
+    int type;
+    const char *alias; /* null until first dtr_obj_alias(). do not free */
+    dtr *dt;
+};
+
+dtr_map *dtr_map_add(dtr_map *map, uint32_t v, const char *label, const char *path) {
+    dtr_map *it;
+    dtr_map *nmap = malloc(sizeof(dtr_map));
+    memset(nmap, 0, sizeof(dtr_map));
+    nmap->v = v;
+
+    //printf("dtr_map_add: 0x%x: %x - %s - %s\n", map, v, label, path);
+
+    if (label != NULL) nmap->label = strdup(label);
+    if (path != NULL) nmap->path = strdup(path);
+    if (map == NULL)
+        return nmap;
+
+    it = map;
+    while(it->next != NULL)
+        it = it->next;
+    it->next = nmap;
+
+    return nmap;
+}
+
+void dtr_map_free(dtr_map *map) {
+    dtr_map *it;
+    while(map != NULL) {
+        it = map->next;
+        free(map->label);
+        free(map->path);
+        free(map);
+        map = it;
+    }
+}
+
+const char *dtr_phandle_lookup(dtr *s, uint32_t v) {
+    dtr_map *phi = s->phandles;
+    while(phi != NULL) {
+        if (phi->v == v)
+            return phi->path;
+        phi = phi->next;
+    }
+    return NULL;
+}
+
+const char *dtr_alias_lookup(dtr *s, const char* label) {
+    dtr_map *ali = s->aliases;
+    while(ali != NULL) {
+        if (strcmp(ali->label, label) == 0)
+            return ali->path;
+        ali = ali->next;
+    }
+    return NULL;
+}
+
+const char *dtr_alias_lookup_by_path(dtr *s, const char* path) {
+    dtr_map *ali = s->aliases;
+    while(ali != NULL) {
+        if (strcmp(ali->path, path) == 0)
+            return ali->label;
+        ali = ali->next;
+    }
+    return NULL;
+}
+
+void _dtr_read_aliases(dtr *);
+void _dtr_map_phandles(dtr *, char *np);
+
+dtr *dtr_new_x(char *base_path, int fast) {
+    dtr *dt = malloc(sizeof(dtr));
+    if (dt != NULL) {
+        memset(dt, 0, sizeof(dtr));
+        if (base_path != NULL)
+            dt->base_path = strdup(base_path);
+        else
+            dt->base_path = strdup(DTR_ROOT);
+
+        /* build alias and phandle lists */
+        dt->aliases = NULL;
+        dt->phandles = NULL;
+        if (!fast) {
+            _dtr_read_aliases(dt);
+            _dtr_map_phandles(dt, "");
+        }
+    }
+    return dt;
+}
+
+dtr *dtr_new(char *base_path) {
+    return dtr_new_x(base_path, 0);
+}
+
+void dtr_free(dtr *s) {
+    if (s != NULL) {
+        dtr_map_free(s->aliases);
+        dtr_map_free(s->phandles);
+        free(s->base_path);
+        free(s);
+    }
+}
+
+const char *dtr_base_path(dtr *s) {
+    if (s)
+        return s->base_path;
+    return NULL;
+}
+
+/*glib, but _dt_obj *prop uses malloc() and std types */
+dtr_obj *dtr_obj_read(dtr *s, const char *dtp) {
+    char *full_path;
+    char *slash;
+    dtr_obj *obj;
+
+    if (dtp == NULL)
+        return NULL;
+
+    obj = malloc(sizeof(dtr_obj));
+    if (obj != NULL) {
+        memset(obj, 0, sizeof(dtr_obj));
+        obj->dt = s;
+        if (*dtp != '/') {
+            obj->path = (char*)dtr_alias_lookup(s, dtp);
+            if (obj->path != NULL)
+                obj->path = strdup(obj->path);
+            else {
+                // obj->path = strdup( (dtp != NULL && strcmp(dtp, "")) ? dtp : "/" );
+                dtr_obj_free(obj);
+                return NULL;
+            }
+        } else
+            obj->path = strdup(dtp);
+
+        full_path = g_strdup_printf("%s%s", s->base_path, obj->path);
+
+        if ( g_file_test(full_path, G_FILE_TEST_IS_DIR) ) {
+            obj->type = DT_NODE;
+        } else {
+            obj->type = DTP_UNK;
+            if (!g_file_get_contents(full_path, (gchar**)&obj->data, (gsize*)&obj->length, NULL)) {
+                dtr_obj_free(obj);
+                g_free(full_path);
+                return NULL;
+            }
+        }
+        g_free(full_path);
+
+        /* find name after last slash, or start */
+        slash = strrchr(obj->path, '/');
+        if (slash != NULL)
+            obj->name = strdup(slash + 1);
+        else
+            obj->name = strdup(obj->path);
+
+        if (obj->type == DTP_UNK)
+            obj->type = dtr_guess_type(obj);
+
+        return obj;
+    }
+    return NULL;
+}
+
+void dtr_obj_free(dtr_obj *s) {
+    if (s != NULL) {
+        free(s->path);
+        free(s->name);
+        free(s->data);
+        free(s);
+    }
+}
+
+int dtr_obj_type(dtr_obj *s) {
+    if (s)
+        return s->type;
+    return DT_TYPE_ERR;
+}
+
+char *dtr_obj_alias(dtr_obj *s) {
+    if (s) {
+        if (s->alias != NULL)
+            return (char*)s->alias;
+
+        s->alias = dtr_alias_lookup_by_path(s->dt, s->path);
+        return (char*)s->alias;
+    }
+    return NULL;
+}
+
+char *dtr_obj_path(dtr_obj *s) {
+    if (s)
+        return s->path;
+    return NULL;
+}
+
+char *dtr_obj_full_path(dtr_obj *s) {
+    if (s) {
+        if (strcmp(s->path, "/") == 0)
+            return g_strdup_printf("%s", s->dt->base_path);
+        else
+            return g_strdup_printf("%s%s", s->dt->base_path, s->path);
+    }
+    return NULL;
+}
+
+dtr_obj *dtr_get_prop_obj(dtr *s, dtr_obj *node, const char *name) {
+    dtr_obj *prop;
+    char *ptmp;
+    ptmp = g_strdup_printf("%s/%s", (node == NULL) ? "" : node->path, name);
+    prop = dtr_obj_read(s, ptmp);
+    g_free(ptmp);
+    return prop;
+}
+
+char *dtr_get_prop_str(dtr *s, dtr_obj *node, const char *name) {
+    dtr_obj *prop;
+    char *ptmp;
+    char *ret = NULL;
+
+    ptmp = g_strdup_printf("%s/%s", (node == NULL) ? "" : node->path, name);
+    prop = dtr_obj_read(s, ptmp);
+    if (prop != NULL && prop->data != NULL) {
+        ret = strdup(prop->data_str);
+        dtr_obj_free(prop);
+    }
+    g_free(ptmp);
+    return ret;
+}
+
+char *dtr_get_string(const char *p) {
+    dtr *dt = dtr_new_x(NULL, 1);
+    char *ret;
+    ret = dtr_get_prop_str(dt, NULL, p);
+    dtr_free(dt);
+    return ret;
+}
+
+uint32_t dtr_get_prop_u32(dtr *s, dtr_obj *node, const char *name) {
+    dtr_obj *prop;
+    char *ptmp;
+    uint32_t ret = 0;
+
+    ptmp = g_strdup_printf("%s/%s", (node == NULL) ? "" : node->path, name);
+    prop = dtr_obj_read(s, ptmp);
+    if (prop != NULL && prop->data != NULL) {
+        ret = be32toh(*prop->data_int);
+        dtr_obj_free(prop);
+    }
+    g_free(ptmp);
+    return ret;
+}
+
+int dtr_guess_type(dtr_obj *obj) {
+    char *tmp, *dash;
+    int i = 0, anc = 0, might_be_str = 1;
+
+    if (obj->length == 0)
+        return DTP_EMPTY;
+
+    /* special #(.*)-cells names are UINT */
+    if (*obj->name == '#') {
+        dash = strrchr(obj->name, '-');
+        if (dash != NULL) {
+            if (strcmp(dash, "-cells") == 0)
+                return DTP_UINT;
+        }
+    }
+
+    /* lookup known type */
+    while (prop_types[i].name != NULL) {
+        if (strcmp(obj->name, prop_types[i].name) == 0)
+            return prop_types[i].type;
+        i++;
+    }
+
+    /* maybe a string? */
+    for (i = 0; i < obj->length; i++) {
+        tmp = (char*)obj->data + i;
+        if ( isalnum(*tmp) ) anc++; /* count the alpha-nums */
+        if ( isprint(*tmp) || *tmp == 0 )
+            continue;
+        might_be_str = 0;
+        break;
+    }
+    if (might_be_str &&
+        ( anc >= obj->length - 2 /* all alpha-nums but ^/ and \0$ */
+          || anc >= 5 ) /*arbitrary*/)
+        return DTP_STR;
+
+    /* multiple of 4 bytes, try list of hex values */
+    if (!(obj->length % 4))
+        return DTP_HEX;
+
+    return DTP_UNK;
+}
+
+char *dtr_elem_phref(dtr *s, dt_uint e) {
+    char *ph_path, *al_label, *ret = NULL;
+    ph_path = (char*)dtr_phandle_lookup(s, be32toh(e));
+    if (ph_path != NULL) {
+        al_label = (char*)dtr_alias_lookup_by_path(s, ph_path);
+        if (al_label != NULL) {
+            ret = g_strdup_printf("&%s", al_label);
+        }
+    }
+    free(ph_path);
+    free(al_label);
+    if (ret == NULL)
+        ret = dtr_elem_hex(e);
+    return ret;
+}
+
+char *dtr_elem_hex(dt_uint e) {
+    return g_strdup_printf("0x%x", be32toh(e) );
+}
+
+char *dtr_elem_byte(uint8_t e) {
+    return g_strdup_printf("%x", e);
+}
+
+char *dtr_elem_uint(dt_uint e) {
+    return g_strdup_printf("%u", be32toh(e) );
+}
+
+char *dtr_list_byte(uint8_t *bytes, unsigned long count) {
+    char *ret, *dest;
+    char buff[4] = "";  /* max element: " 00\0" */
+    uint32_t v;
+    unsigned long i, l;
+    l = count * 4 + 1;
+    ret = malloc(l);
+    memset(ret, 0, l);
+    strcpy(ret, "[");
+    dest = ret + 1;
+    for (i = 0; i < count; i++) {
+        v = bytes[i];
+        sprintf(buff, "%s%02x", (i) ? " " : "", v);
+        l = strlen(buff);
+        strncpy(dest, buff, l);
+        dest += l;
+    }
+    strcpy(dest, "]");
+    return ret;
+}
+
+char *dtr_list_hex(dt_uint *list, unsigned long count) {
+    char *ret, *dest;
+    char buff[12] = "";  /* max element: " 0x00000000\0" */
+    unsigned long i, l;
+    l = count * 12 + 1;
+    dest = ret = malloc(l);
+    memset(ret, 0, l);
+    for (i = 0; i < count; i++) {
+        sprintf(buff, "%s0x%x", (i) ? " " : "", be32toh(list[i]));
+        l = strlen(buff);
+        strncpy(dest, buff, l);
+        dest += l;
+    }
+    return ret;
+}
+
+/*cstd, except for g_strescape()*/
+char *dtr_list_str0(const char *data, uint32_t length) {
+    char *tmp, *esc, *next_str;
+    char ret[1024] = "";
+    uint32_t l, tl;
+
+    /* treat as null-separated string list */
+    tl = 0;
+    strcpy(ret, "");
+    tmp = ret;
+    next_str = (char*)data;
+    while(next_str != NULL) {
+        l = strlen(next_str);
+        esc = g_strescape(next_str, NULL);
+        sprintf(tmp, "%s\"%s\"",
+                strlen(ret) ? ", " : "", esc);
+        free(esc);
+        tmp += strlen(tmp);
+        tl += l + 1; next_str += l + 1;
+        if (tl >= length) break;
+    }
+
+    return strdup(ret);
+}
+
+char* dtr_str(dtr *s, dtr_obj *obj) {
+    char *ret;
+    int type;
+
+    if (obj == NULL) return NULL;
+    type = obj->type;
+
+    if (type == DTP_PH_REF) {
+        if (!DTEX_PHREFS || obj->length != 4)
+            type = DTP_HEX;
+    }
+
+    switch(type) {
+        case DT_NODE:
+            ret = strdup("{node}");
+            break;
+        case DTP_EMPTY:
+            ret = strdup("{empty}");
+            break;
+        case DTP_STR:
+            ret = dtr_list_str0(obj->data_str, obj->length);
+            break;
+        case DTP_PH:
+        case DTP_HEX:
+            if (obj->length % 4)
+                ret = dtr_list_byte((uint8_t*)obj->data, obj->length);
+            else
+                ret = dtr_list_hex(obj->data, obj->length / 4);
+            break;
+        case DTP_PH_REF:
+            ret = dtr_elem_phref(s, *obj->data_int);
+            break;
+        case DTP_UINT:
+            ret = dtr_elem_uint(*obj->data_int);
+            break;
+        case DTP_UNK:
+        default:
+            if (obj->length > 64) /* maybe should use #define at the top */
+                ret = g_strdup_printf(ret, "{data} (%lu bytes)", obj->length);
+            else
+                ret = dtr_list_byte((uint8_t*)obj->data, obj->length);
+            break;
+    }
+
+    return ret;
+}
+
+void _dtr_read_aliases(dtr *s) {
+    gchar *dir_path;
+    GDir *dir;
+    const gchar *fn;
+    dtr_obj *anode, *prop;
+    dtr_map *al;
+    anode = dtr_obj_read(s, "/aliases");
+
+    dir_path = g_strdup_printf("%s/aliases", s->base_path);
+    dir = g_dir_open(dir_path, 0 , NULL);
+    if (dir) {
+        while((fn = g_dir_read_name(dir)) != NULL) {
+            prop = dtr_get_prop_obj(s, anode, fn);
+            if (prop->type == DTP_STR) {
+                al = dtr_map_add(s->aliases, 0, prop->name, prop->data_str);
+                if (s->aliases == NULL)
+                    s->aliases = al;
+            }
+            dtr_obj_free(prop);
+        }
+    }
+    g_dir_close(dir);
+    g_free(dir_path);
+    dtr_obj_free(anode);
+}
+
+/* TODO: rewrite */
+void _dtr_map_phandles(dtr *s, char *np) {
+    gchar *dir_path;
+    gchar *ftmp, *ntmp, *ptmp;
+    const gchar *fn;
+    GDir *dir;
+    dtr_obj *prop, *ph_prop;
+    dtr_map *ph;
+    uint32_t phandle;
+
+    if (np == NULL) np = "";
+    dir_path = g_strdup_printf("%s/%s", s->base_path, np);
+
+    prop = dtr_obj_read(s, np);
+    dir = g_dir_open(dir_path, 0 , NULL);
+    if (dir) {
+        while((fn = g_dir_read_name(dir)) != NULL) {
+            ftmp = g_strdup_printf("%s/%s", dir_path, fn);
+            if ( g_file_test(ftmp, G_FILE_TEST_IS_DIR) ) {
+                ntmp = g_strdup_printf("%s/%s", np, fn);
+                ptmp = g_strdup_printf("%s/phandle", ntmp);
+                ph_prop = dtr_obj_read(s, ptmp);
+                if (ph_prop != NULL) {
+                    ph = dtr_map_add(s->phandles, be32toh(*ph_prop->data_int), NULL, ntmp);
+                    if (s->phandles == NULL)
+                        s->phandles = ph;
+                }
+                _dtr_map_phandles(s, ntmp);
+                g_free(ptmp);
+                g_free(ntmp);
+                dtr_obj_free(ph_prop);
+            }
+            g_free(ftmp);
+        }
+    }
+    g_dir_close(dir);
+    dtr_obj_free(prop);
+}
+
+