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author | Maarten Brock <m.brock@vanmierlo.com> | 2019-11-25 14:15:29 +0100 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-01-14 14:34:04 +0100 |
commit | 422c6d3b09afb187b5aeedc3a99d759703023be0 (patch) | |
tree | 6acd6145dcf8d035190c6dc37c133387ce05d53b | |
parent | tty/serial: 8250_exar: use true,false for bool variable (diff) | |
download | linux-422c6d3b09afb187b5aeedc3a99d759703023be0.tar.xz linux-422c6d3b09afb187b5aeedc3a99d759703023be0.zip |
serial: xilinx_uartps: Let get_mctrl return status
Some of the applications like microcom do not work if
modem is disabled. To fix them we always return
TIOCM_CTS | TIOCM_DSR | TIOCM_CAR instead of 0 when
using cts_override. Make get_mctrl return actual status
when not using cts_override.
Signed-off-by: Maarten Brock <m.brock@vanmierlo.com>
Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Link: https://lore.kernel.org/r/1574687731-21563-1-git-send-email-shubhrajyoti.datta@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | drivers/tty/serial/xilinx_uartps.c | 28 |
1 files changed, 25 insertions, 3 deletions
diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c index 2b5606469bed..f33b89587786 100644 --- a/drivers/tty/serial/xilinx_uartps.c +++ b/drivers/tty/serial/xilinx_uartps.c @@ -154,6 +154,16 @@ MODULE_PARM_DESC(rx_timeout, "Rx timeout, 1-255"); #define CDNS_UART_MODEMCR_DTR 0x00000001 /* Data Terminal Ready */ /* + * Modem Status register: + * The read/write Modem Status register reports the interface with the modem + * or data set, or a peripheral device emulating a modem. + */ +#define CDNS_UART_MODEMSR_DCD BIT(7) /* Data Carrier Detect */ +#define CDNS_UART_MODEMSR_RI BIT(6) /* Ting Indicator */ +#define CDNS_UART_MODEMSR_DSR BIT(5) /* Data Set Ready */ +#define CDNS_UART_MODEMSR_CTS BIT(4) /* Clear To Send */ + +/* * Channel Status Register: * The channel status register (CSR) is provided to enable the control logic * to monitor the status of bits in the channel interrupt status register, @@ -1003,12 +1013,24 @@ static void cdns_uart_config_port(struct uart_port *port, int flags) */ static unsigned int cdns_uart_get_mctrl(struct uart_port *port) { + u32 val; + unsigned int mctrl = 0; struct cdns_uart *cdns_uart_data = port->private_data; if (cdns_uart_data->cts_override) - return 0; - - return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR; + return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR; + + val = readl(port->membase + CDNS_UART_MODEMSR); + if (val & CDNS_UART_MODEMSR_CTS) + mctrl |= TIOCM_CTS; + if (val & CDNS_UART_MODEMSR_DSR) + mctrl |= TIOCM_DSR; + if (val & CDNS_UART_MODEMSR_RI) + mctrl |= TIOCM_RNG; + if (val & CDNS_UART_MODEMSR_DCD) + mctrl |= TIOCM_CAR; + + return mctrl; } static void cdns_uart_set_mctrl(struct uart_port *port, unsigned int mctrl) |