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 | |
| parent | tty: serial: samsung_tty: support more than 4 uart ports (diff) | |
| download | linux-dev-72a43046b61a3fe7164a622224bcdfc3cf6b795d.tar.xz linux-dev-72a43046b61a3fe7164a622224bcdfc3cf6b795d.zip | |
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>
| -rw-r--r-- | drivers/tty/serial/samsung_tty.c | 8 | ||||
| -rw-r--r-- | include/linux/serial_s3c.h | 2 |
2 files changed, 9 insertions, 1 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) diff --git a/include/linux/serial_s3c.h b/include/linux/serial_s3c.h index dec15f5b3dec..1672cf0810ef 100644 --- a/include/linux/serial_s3c.h +++ b/include/linux/serial_s3c.h @@ -83,7 +83,7 @@ #define S3C2410_UCON_RXIRQMODE (1<<0) #define S3C2410_UCON_RXFIFO_TOI (1<<7) #define S3C2443_UCON_RXERR_IRQEN (1<<6) -#define S3C2443_UCON_LOOPBACK (1<<5) +#define S3C2410_UCON_LOOPBACK (1<<5) #define S3C2410_UCON_DEFAULT (S3C2410_UCON_TXILEVEL | \ S3C2410_UCON_RXILEVEL | \ |