linux-kernel - [PATCH v2] serial: samsung: add support for manual RTS setting

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <1379519569-7266-1-git-send-email-jose.goncalves@inov.pt>
Date:	Wed, 18 Sep 2013 16:52:49 +0100
From:	José Miguel Gonçalves 
	<jose.goncalves@...v.pt>
To:	t.figa@...sung.com
Cc:	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	linux-samsung-soc@...r.kernel.org, linux-serial@...r.kernel.org,
	linux-kernel@...r.kernel.org, heiko@...ech.de,
	s.nawrocki@...sung.com,
	José Miguel Gonçalves 
	<jose.goncalves@...v.pt>
Subject: [PATCH v2] serial: samsung: add support for manual RTS setting

The Samsung serial driver currently does not support setting the
RTS pin with an ioctl(TIOCMSET) call. This patch adds this support.

Changes in v2:
 - Preserve the RTS pin's manual setting  in set_termios() also when
   enabling CRTSCTS.

Signed-off-by: José Miguel Gonçalves <jose.goncalves@...v.pt>
---
 drivers/tty/serial/samsung.c |   20 +++++++++++++++++---
 1 file changed, 17 insertions(+), 3 deletions(-)

diff --git a/drivers/tty/serial/samsung.c b/drivers/tty/serial/samsung.c
index f3dfa19..401ef4f 100644
--- a/drivers/tty/serial/samsung.c
+++ b/drivers/tty/serial/samsung.c
@@ -407,7 +407,14 @@ static unsigned int s3c24xx_serial_get_mctrl(struct uart_port *port)
 
 static void s3c24xx_serial_set_mctrl(struct uart_port *port, unsigned int mctrl)
 {
-	/* todo - possibly remove AFC and do manual CTS */
+	unsigned int umcon = rd_regl(port, S3C2410_UMCON);
+
+	if (mctrl & TIOCM_RTS)
+		umcon |= S3C2410_UMCOM_RTS_LOW;
+	else
+		umcon &= ~S3C2410_UMCOM_RTS_LOW;
+
+	wr_regl(port, S3C2410_UMCON, umcon);
 }
 
 static void s3c24xx_serial_break_ctl(struct uart_port *port, int break_state)
@@ -774,8 +781,6 @@ static void s3c24xx_serial_set_termios(struct uart_port *port,
 	if (termios->c_cflag & CSTOPB)
 		ulcon |= S3C2410_LCON_STOPB;
 
-	umcon = (termios->c_cflag & CRTSCTS) ? S3C2410_UMCOM_AFC : 0;
-
 	if (termios->c_cflag & PARENB) {
 		if (termios->c_cflag & PARODD)
 			ulcon |= S3C2410_LCON_PODD;
@@ -792,6 +797,15 @@ static void s3c24xx_serial_set_termios(struct uart_port *port,
 
 	wr_regl(port, S3C2410_ULCON, ulcon);
 	wr_regl(port, S3C2410_UBRDIV, quot);
+
+	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;
+	} else {
+		umcon &= ~S3C2410_UMCOM_AFC;
+	}
 	wr_regl(port, S3C2410_UMCON, umcon);
 
 	if (ourport->info->has_divslot)
-- 
1.7.10.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/