From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sasha Levin Subject: [PATCH AUTOSEL 4.14 105/170] tty: serial: samsung: Properly set flags in autoCTS mode Date: Mon, 28 Jan 2019 11:10:55 -0500 Message-ID: <20190128161200.55107-105-sashal@kernel.org> References: <20190128161200.55107-1-sashal@kernel.org> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20190128161200.55107-1-sashal@kernel.org> Sender: linux-kernel-owner@vger.kernel.org To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Beomho Seo , Marek Szyprowski , Greg Kroah-Hartman , Sasha Levin , linux-serial@vger.kernel.org List-Id: linux-serial@vger.kernel.org From: Beomho Seo [ Upstream commit 31e933645742ee6719d37573a27cce0761dcf92b ] Commit 391f93f2ec9f ("serial: core: Rework hw-assited flow control support") has changed the way the autoCTS mode is handled. According to that change, serial drivers which enable H/W autoCTS mode must set UPSTAT_AUTOCTS to prevent the serial core from inadvertently disabling TX. This patch adds proper handling of UPSTAT_AUTOCTS flag. Signed-off-by: Beomho Seo [mszyprow: rephrased commit message] Signed-off-by: Marek Szyprowski Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/tty/serial/samsung.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/tty/serial/samsung.c b/drivers/tty/serial/samsung.c index 57baa84ccf86..f4b8e4e17a86 100644 --- a/drivers/tty/serial/samsung.c +++ b/drivers/tty/serial/samsung.c @@ -1343,11 +1343,14 @@ static void s3c24xx_serial_set_termios(struct uart_port *port, wr_regl(port, S3C2410_ULCON, ulcon); wr_regl(port, S3C2410_UBRDIV, quot); + port->status &= ~UPSTAT_AUTOCTS; + umcon = rd_regl(port, S3C2410_UMCON); if (termios->c_cflag & CRTSCTS) { umcon |= S3C2410_UMCOM_AFC; /* Disable RTS when RX FIFO contains 63 bytes */ umcon &= ~S3C2412_UMCON_AFC_8; + port->status = UPSTAT_AUTOCTS; } else { umcon &= ~S3C2410_UMCOM_AFC; } -- 2.19.1