From mboxrd@z Thu Jan 1 00:00:00 1970 From: Helmut Grohne Subject: [PATCH v3 0/3] serial: xuartps: hardware race condition and cleanup Date: Mon, 4 Jun 2018 12:21:56 +0200 Message-ID: Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Return-path: Content-Disposition: inline List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: Greg Kroah-Hartman , Michal Simek , linux-serial@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org, Uwe =?iso-8859-1?Q?Kleine-K=F6nig?= List-Id: linux-serial@vger.kernel.org The character transmission in xuartps is racy. If the transmitter is disabl= ed early, the device is confused and produces a desync. Garbage on the remote = end can be a visible symptom. The second patch in this series tries to reduce t= hat race condition in accordance with the hardware documentation, but it cannot remove it entirely. The first and third patches are code cleanup. Changes since v2: * Do not attempt to disable the transmitter after a transmission (original behaviour around 3.14). These patches no longer touch with the transmitt= er state at all as requested by S=F6ren Brinkmann. * Add Acked-by/Reviewed-by tags from S=F6ren Brinkmann after addressing his remarks. Earlier patches/discussion at: https://www.spinics.net/lists/linux-serial/msg23145.html https://www.spinics.net/lists/linux-serial/msg23156.html https://www.spinics.net/lists/linux-serial/msg23157.html Helmut Grohne (3): serial: xuartps: fix typo in cdns_uart_startup serial: xuartps: reduce hardware TX race condition serial: xuartps: remove unnecessary register write drivers/tty/serial/xilinx_uartps.c | 23 ++++++++--------------- 1 file changed, 8 insertions(+), 15 deletions(-) -- = 2.11.0