diff options
| author | Chanho Park <chanho61.park@samsung.com> | 2022-06-29 09:41:41 +0900 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-06-30 17:09:08 +0200 |
| commit | 72a43046b61a3fe7164a622224bcdfc3cf6b795d (patch) | |
| tree | 3e0487e215631ae6b6a4b4dd66615257f49931de /drivers/tty/serial/samsung_tty.c | |
| parent | 9636047ffafcf5988946c05f0ebd7e0b2114aa74 (diff) | |
tty: serial: samsung_tty: loopback mode support
Internal loopback mode can be supported by setting
UCON register's Loopback Mode bit. The mode & bit can be supported
since s3c2410 and later SoCs. The prefix of LOOPBACK / BIT(5) naming
should be also changed to S3C2410_ in order to avoid confusion.
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Chanho Park <chanho61.park@samsung.com>
Link: https://lore.kernel.org/r/20220629004141.51484-1-chanho61.park@samsung.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/serial/samsung_tty.c')
| -rw-r--r-- | drivers/tty/serial/samsung_tty.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/tty/serial/samsung_tty.c b/drivers/tty/serial/samsung_tty.c index 3e0aa2923605..8971fbb49fa3 100644 --- a/drivers/tty/serial/samsung_tty.c +++ b/drivers/tty/serial/samsung_tty.c @@ -1018,6 +1018,7 @@ static unsigned int s3c24xx_serial_get_mctrl(struct uart_port *port) static void s3c24xx_serial_set_mctrl(struct uart_port *port, unsigned int mctrl) { unsigned int umcon = rd_regl(port, S3C2410_UMCON); + unsigned int ucon = rd_reg(port, S3C2410_UCON); if (mctrl & TIOCM_RTS) umcon |= S3C2410_UMCOM_RTS_LOW; @@ -1025,6 +1026,13 @@ static void s3c24xx_serial_set_mctrl(struct uart_port *port, unsigned int mctrl) umcon &= ~S3C2410_UMCOM_RTS_LOW; wr_regl(port, S3C2410_UMCON, umcon); + + if (mctrl & TIOCM_LOOP) + ucon |= S3C2410_UCON_LOOPBACK; + else + ucon &= ~S3C2410_UCON_LOOPBACK; + + wr_regl(port, S3C2410_UCON, ucon); } static void s3c24xx_serial_break_ctl(struct uart_port *port, int break_state) |