setup_audio_gpio(const char *name, const char* compatible, int *gpio_addr, int* gpio_pol)
 {
        struct device_node *np;
-       u32* pp;
-       
+       const u32* pp;
+
        np = find_devices("gpio");
        if (!np)
                return -ENODEV;
        np = np->child;
        while(np != 0) {
                if (name) {
-                       char *property = get_property(np,"audio-gpio",NULL);
+                       const char *property =
+                               get_property(np,"audio-gpio",NULL);
                        if (property != 0 && strcmp(property,name) == 0)
                                break;
                } else if (compatible && device_is_compatible(np, compatible))
        }
        if (!np)
                return -ENODEV;
-       pp = (u32 *)get_property(np, "AAPL,address", NULL);
+       pp = get_property(np, "AAPL,address", NULL);
        if (!pp)
                return -ENODEV;
        *gpio_addr = (*pp) & 0x0000ffff;
-       pp = (u32 *)get_property(np, "audio-gpio-active-state", NULL);
+       pp = get_property(np, "audio-gpio-active-state", NULL);
        if (pp)
                *gpio_pol = *pp;
        else
 
                return NULL;
   
        for (np = np->child; np; np = np->sibling) {
-               char *property = get_property(np, "audio-gpio", NULL);
+               const char *property = get_property(np, "audio-gpio", NULL);
                if (property && strcmp(property, name) == 0)
                        return np;
        }  
                                struct pmac_gpio *gp, int is_compatible)
 {
        struct device_node *node;
-       u32 *base, addr;
+       const u32 *base;
+       u32 addr;
 
        if (is_compatible)
                node = find_compatible_audio_device(device);
                return -ENODEV;
        }
 
-       base = (u32 *)get_property(node, "AAPL,address", NULL);
+       base = get_property(node, "AAPL,address", NULL);
        if (! base) {
-               base = (u32 *)get_property(node, "reg", NULL);
+               base = get_property(node, "reg", NULL);
                if (!base) {
                        DBG("(E) cannot find address for device %s !\n", device);
                        snd_printd("cannot find address for device %s\n", device);
 
        gp->addr = addr & 0x0000ffff;
        /* Try to find the active state, default to 0 ! */
-       base = (u32 *)get_property(node, "audio-gpio-active-state", NULL);
+       base = get_property(node, "audio-gpio-active-state", NULL);
        if (base) {
                gp->active_state = *base;
                gp->active_val = (*base) ? 0x5 : 0x4;
                gp->inactive_val = (*base) ? 0x4 : 0x5;
        } else {
-               u32 *prop = NULL;
+               const u32 *prop = NULL;
                gp->active_state = 0;
                gp->active_val = 0x4;
                gp->inactive_val = 0x5;
                 * as we don't yet have an interpreter for these things
                 */
                if (platform)
-                       prop = (u32 *)get_property(node, platform, NULL);
+                       prop = get_property(node, platform, NULL);
                if (prop) {
                        if (prop[3] == 0x9 && prop[4] == 0x9) {
                                gp->active_val = 0xd;