Commit 422c6d3b authored by Maarten Brock's avatar Maarten Brock Committed by Greg Kroah-Hartman
Browse files

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: default avatarMaarten Brock <m.brock@vanmierlo.com>
Signed-off-by: default avatarShubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Link: https://lore.kernel.org/r/1574687731-21563-1-git-send-email-shubhrajyoti.datta@gmail.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 67e977f3

drivers/tty/serial/xilinx_uartps.c

+25 −3
Original line number Diff line number Diff line
@@ -153,6 +153,16 @@ MODULE_PARM_DESC(rx_timeout, "Rx timeout, 1-255"); 
#define CDNS_UART_MODEMCR_RTS	0x00000002 /* Request to send output control */

#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
@@ -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;



	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)

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