| From c649509d4b4a91a603c8185ab72f99427579f50c Mon Sep 17 00:00:00 2001 |
| From: Paul Mundt <lethal@linux-sh.org> |
| Date: Thu, 24 Nov 2011 20:20:53 +0900 |
| Subject: serial: sh-sci: Add support for loopback mode. |
| |
| This plugs in loopback control for SCFCR-enabled ports and plugs it in |
| via the TIOCM_LOOP control, as others do. |
| |
| Signed-off-by: Paul Mundt <lethal@linux-sh.org> |
| (cherry picked from commit dc7e3ef7dade7041fb1809f2a5403efac655a791) |
| |
| Signed-off-by: Simon Horman <horms@verge.net.au> |
| --- |
| drivers/tty/serial/sh-sci.c | 15 ++++++++++++++- |
| 1 file changed, 14 insertions(+), 1 deletion(-) |
| |
| diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c |
| index a60ccdb..b519332 100644 |
| --- a/drivers/tty/serial/sh-sci.c |
| +++ b/drivers/tty/serial/sh-sci.c |
| @@ -1113,10 +1113,23 @@ static unsigned int sci_tx_empty(struct uart_port *port) |
| * handled via the ->init_pins() op, which is a bit of a one-way street, |
| * lacking any ability to defer pin control -- this will later be |
| * converted over to the GPIO framework). |
| + * |
| + * Other modes (such as loopback) are supported generically on certain |
| + * port types, but not others. For these it's sufficient to test for the |
| + * existence of the support register and simply ignore the port type. |
| */ |
| static void sci_set_mctrl(struct uart_port *port, unsigned int mctrl) |
| { |
| - /* Nothing to do here. */ |
| + if (mctrl & TIOCM_LOOP) { |
| + struct plat_sci_reg *reg; |
| + |
| + /* |
| + * Standard loopback mode for SCFCR ports. |
| + */ |
| + reg = sci_getreg(port, SCFCR); |
| + if (reg->size) |
| + sci_out(port, SCFCR, sci_in(port, SCFCR) | 1); |
| + } |
| } |
| |
| static unsigned int sci_get_mctrl(struct uart_port *port) |
| -- |
| 1.7.10 |
| |
