TTY_IO code cleanups

index 47a6eac..7b42c55 100644
@@ -331,7 +331,7 @@ static struct tty_buffer *tty_buffer_alloc(struct tty_struct *tty, size_t size)
 	p->next = NULL;
 	p->commit = 0;
 	p->read = 0;
-	p->char_buf_ptr = (char *)(p->data);
+	p->char_buf_ptr = (char *)p->data;
 	p->flag_buf_ptr = (unsigned char *)p->char_buf_ptr + size;
 	tty->buf.memory_used += size;
 	return p;

@@ -640,7 +640,6 @@ static struct tty_ldisc tty_ldiscs[NR_LDISCS];	/* line disc dispatch table */
 int tty_register_ldisc(int disc, struct tty_ldisc *new_ldisc)
 {
 	unsigned long flags;
-	int ret = 0;
 	
 	if (disc < N_TTY || disc >= NR_LDISCS)
 		return -EINVAL;

@@ -652,7 +651,7 @@ int tty_register_ldisc(int disc, struct tty_ldisc *new_ldisc)
 	tty_ldiscs[disc].refcount = 0;
 	spin_unlock_irqrestore(&tty_ldisc_lock, flags);
 	
-	return ret;
+	return 0;
 }
 EXPORT_SYMBOL(tty_register_ldisc);
 

@@ -791,17 +790,15 @@ static int tty_ldisc_try(struct tty_struct *tty)
 {
 	unsigned long flags;
 	struct tty_ldisc *ld;
-	int ret = 0;
 	
 	spin_lock_irqsave(&tty_ldisc_lock, flags);
 	ld = &tty->ldisc;
-	if(test_bit(TTY_LDISC, &tty->flags))
-	{
+	if(test_bit(TTY_LDISC, &tty->flags)) {
 		ld->refcount++;
-		ret = 1;
+		return 1;
 	}
 	spin_unlock_irqrestore(&tty_ldisc_lock, flags);
-	return ret;
+	return 0;
 }
 
 /**

@@ -1932,19 +1929,16 @@ static int init_dev(struct tty_driver *driver, int idx,
 	}
 
 	if (!*tp_loc) {
-		tp = (struct ktermios *) kmalloc(sizeof(struct ktermios),
-						GFP_KERNEL);
+		tp = kmalloc(sizeof(struct ktermios), GFP_KERNEL);
 		if (!tp)
 			goto free_mem_out;
 		*tp = driver->init_termios;
 	}
 
 	if (!*ltp_loc) {
-		ltp = (struct ktermios *) kmalloc(sizeof(struct ktermios),
-						 GFP_KERNEL);
+		ltp = kzalloc(sizeof(struct ktermios), GFP_KERNEL);
 		if (!ltp)
 			goto free_mem_out;
-		memset(ltp, 0, sizeof(struct ktermios));
 	}
 
 	if (driver->type == TTY_DRIVER_TYPE_PTY) {

@@ -1965,19 +1959,16 @@ static int init_dev(struct tty_driver *driver, int idx,
 		}
 
 		if (!*o_tp_loc) {
-			o_tp = (struct ktermios *)
-				kmalloc(sizeof(struct ktermios), GFP_KERNEL);
+			o_tp = kmalloc(sizeof(struct ktermios), GFP_KERNEL);
 			if (!o_tp)
 				goto free_mem_out;
 			*o_tp = driver->other->init_termios;
 		}
 
 		if (!*o_ltp_loc) {
-			o_ltp = (struct ktermios *)
-				kmalloc(sizeof(struct ktermios), GFP_KERNEL);
+			o_ltp = kzalloc(sizeof(struct ktermios), GFP_KERNEL);
 			if (!o_ltp)
 				goto free_mem_out;
-			memset(o_ltp, 0, sizeof(struct ktermios));
 		}
 
 		/*

@@ -3605,9 +3596,8 @@ struct tty_driver *alloc_tty_driver(int lines)
 {
 	struct tty_driver *driver;
 
-	driver = kmalloc(sizeof(struct tty_driver), GFP_KERNEL);
+	driver = kzalloc(sizeof(struct tty_driver), GFP_KERNEL);
 	if (driver) {
-		memset(driver, 0, sizeof(struct tty_driver));
 		driver->magic = TTY_DRIVER_MAGIC;
 		driver->num = lines;
 		/* later we'll move allocation of tables here */

@@ -3667,10 +3657,9 @@ int tty_register_driver(struct tty_driver *driver)
 		return 0;
 
 	if (!(driver->flags & TTY_DRIVER_DEVPTS_MEM)) {
-		p = kmalloc(driver->num * 3 * sizeof(void *), GFP_KERNEL);
+		p = kzalloc(driver->num * 3 * sizeof(void *), GFP_KERNEL);
 		if (!p)
 			return -ENOMEM;
-		memset(p, 0, driver->num * 3 * sizeof(void *));
 	}
 
 	if (!driver->major) {