From mboxrd@z Thu Jan 1 00:00:00 1970 From: akpm@linux-foundation.org Subject: [patch for 2.6.31? 2/2] gigaset: really fix chars_in_buffer Date: Thu, 06 Aug 2009 15:19:32 -0700 Message-ID: <200908062219.n76MJXhY024495@imap1.linux-foundation.org> Cc: netdev@vger.kernel.org, akpm@linux-foundation.org, tilman@imap.cc To: davem@davemloft.net Return-path: Received: from smtp1.linux-foundation.org ([140.211.169.13]:40489 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754340AbZHFWUG (ORCPT ); Thu, 6 Aug 2009 18:20:06 -0400 Sender: netdev-owner@vger.kernel.org List-ID: From: Tilman Schmidt The tty_operation chars_in_buffer() is not allowed to return a negative value to signal an error. Corrects the problem flagged by commit 23198fda7182969b619613a555f8645fdc3dc334, "tty: fix chars_in_buffers". Signed-off-by: Tilman Schmidt Signed-off-by: Andrew Morton --- drivers/isdn/gigaset/interface.c | 19 +++++++------------ 1 file changed, 7 insertions(+), 12 deletions(-) diff -puN drivers/isdn/gigaset/interface.c~gigaset-really-fix-chars_in_buffer drivers/isdn/gigaset/interface.c --- a/drivers/isdn/gigaset/interface.c~gigaset-really-fix-chars_in_buffer +++ a/drivers/isdn/gigaset/interface.c @@ -408,33 +408,28 @@ static int if_write_room(struct tty_stru return retval; } -/* FIXME: This function does not have error returns */ - static int if_chars_in_buffer(struct tty_struct *tty) { struct cardstate *cs; - int retval = -ENODEV; + int retval = 0; cs = (struct cardstate *) tty->driver_data; if (!cs) { pr_err("%s: no cardstate\n", __func__); - return -ENODEV; + return 0; } gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__); - if (mutex_lock_interruptible(&cs->mutex)) - return -ERESTARTSYS; // FIXME -EINTR? + mutex_lock(&cs->mutex); - if (!cs->connected) { + if (!cs->connected) gig_dbg(DEBUG_IF, "not connected"); - retval = -ENODEV; - } else if (!cs->open_count) + else if (!cs->open_count) dev_warn(cs->dev, "%s: device not opened\n", __func__); - else if (cs->mstate != MS_LOCKED) { + else if (cs->mstate != MS_LOCKED) dev_warn(cs->dev, "can't write to unlocked device\n"); - retval = -EBUSY; - } else + else retval = cs->ops->chars_in_buffer(cs); mutex_unlock(&cs->mutex); _