[ALSA] Export snd_ctl_elem_read/write() functions

Control Midlevel,ALSA Core,IOCTL32 emulation
snd_ctl_elem_read() and snd_ctl_elem_write() functions are exported
to be accessible from other kernel modules.  They can be used for
suspend/resume codes, for example.
Signed-off-by: Takashi Iwai <tiwai@suse.de>

include/sound/control.h

@@ -122,9 +122,8 @@ int snd_ctl_unregister(snd_card_t *card);
 int snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn);
 int snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn);
 
-/* for ioctl32 */
 int snd_ctl_elem_read(snd_card_t *card, snd_ctl_elem_value_t *control);
-int snd_ctl_elem_write(snd_ctl_file_t *file, snd_ctl_elem_value_t *control);
+int snd_ctl_elem_write(snd_card_t *card, snd_ctl_file_t *file, snd_ctl_elem_value_t *control);
 
 static inline unsigned int snd_ctl_get_ioffnum(snd_kcontrol_t *kctl, snd_ctl_elem_id_t *id)
 {

sound/core/control.c

@@ -685,9 +685,8 @@ static int snd_ctl_elem_read_user(snd_card_t *card, snd_ctl_elem_value_t __user
 	return result;
 }
 
-int snd_ctl_elem_write(snd_ctl_file_t *file, snd_ctl_elem_value_t *control)
+int snd_ctl_elem_write(snd_card_t *card, snd_ctl_file_t *file, snd_ctl_elem_value_t *control)
 {
-	snd_card_t *card = file->card;
 	snd_kcontrol_t *kctl;
 	snd_kcontrol_volatile_t *vd;
 	unsigned int index_offset;
@@ -706,7 +705,7 @@ int snd_ctl_elem_write(snd_ctl_file_t *file, snd_ctl_elem_value_t *control)
 		} else {
 			if (!(vd->access & SNDRV_CTL_ELEM_ACCESS_WRITE) ||
 			    kctl->put == NULL ||
-			    (vd->owner != NULL && vd->owner != file)) {
+			    (file && vd->owner != NULL && vd->owner != file)) {
 				result = -EPERM;
 			} else {
 				snd_ctl_build_ioff(&control->id, kctl, index_offset);
@@ -735,7 +734,7 @@ static int snd_ctl_elem_write_user(snd_ctl_file_t *file, snd_ctl_elem_value_t __
 		kfree(control);
 		return -EFAULT;
 	}
-	result = snd_ctl_elem_write(file, control);
+	result = snd_ctl_elem_write(file->card, file, control);
 	if (result >= 0)
 		if (copy_to_user(_control, control, sizeof(*control)))
 			result = -EFAULT;

sound/core/ioctl32/ioctl32.c

@@ -357,7 +357,7 @@ static inline int _snd_ioctl32_ctl_elem_value(unsigned int fd, unsigned int cmd,
 	if (native_ctl == SNDRV_CTL_IOCTL_ELEM_READ)
 		err = snd_ctl_elem_read(ctl->card, data);
 	else
-		err = snd_ctl_elem_write(ctl, data);
+		err = snd_ctl_elem_write(ctl->card, ctl, data);
 	if (err < 0)
 		goto __end;
 	/* restore info to 32bit */

sound/core/sound.c

@@ -473,10 +473,8 @@ EXPORT_SYMBOL(snd_ctl_find_id);
 EXPORT_SYMBOL(snd_ctl_notify);
 EXPORT_SYMBOL(snd_ctl_register_ioctl);
 EXPORT_SYMBOL(snd_ctl_unregister_ioctl);
-#ifdef CONFIG_COMPAT
 EXPORT_SYMBOL(snd_ctl_elem_read);
 EXPORT_SYMBOL(snd_ctl_elem_write);
-#endif
   /* misc.c */
 EXPORT_SYMBOL(snd_task_name);
 #ifdef CONFIG_SND_VERBOSE_PRINTK