Commit 93f3350c authored by Claudio Scordino's avatar Claudio Scordino Committed by Greg Kroah-Hartman
Browse files

RS485: fix inconsistencies in the meaning of some variables 



The crisv10.c and the atmel_serial.c serial drivers intepret the fields of the
serial_rs485 structure in a different way.

In particular, crisv10.c uses SER_RS485_RTS_AFTER_SEND and
SER_RS485_RTS_ON_SEND for the voltage of the RTS pin; atmel_serial.c,
instead, uses these values to know if a delay must be set before and
after sending.  This patch makes the usage of these variables consistent
across all drivers and fixes the Documentation as well.

From now on, SER_RS485_RTS_AFTER_SEND and SER_RS485_RTS_ON_SEND will be
used to set the voltage of the RTS pin (as in the crisv10.c driver); the
delay will be understood by looking only at the value of
delay_rts_before_send and delay_rts_after_send.

Signed-off-by: default avatarClaudio Scordino <claudio@evidence.eu.com>
Signed-off-by: default avatarDarron Black <darron@griffin.net>
Acked-by: default avatarJesper Nilsson <jesper.nilsson@axis.com>
Acked-by: default avatarNicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: default avatarAlan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 90f04c29

Documentation/serial/serial-rs485.txt

+11 −3
Original line number Diff line number Diff line
@@ -97,15 +97,23 @@ 


	struct serial_rs485 rs485conf;



	/* Set RS485 mode: */

	/* Enable RS485 mode: */

	rs485conf.flags |= SER_RS485_ENABLED;



	/* Set logical level for RTS pin equal to 1 when sending: */

	rs485conf.flags |= SER_RS485_RTS_ON_SEND;

	/* or, set logical level for RTS pin equal to 0 when sending: */

	rs485conf.flags &= ~(SER_RS485_RTS_ON_SEND);



	/* Set logical level for RTS pin equal to 1 after sending: */

	rs485conf.flags |= SER_RS485_RTS_AFTER_SEND;

	/* or, set logical level for RTS pin equal to 0 after sending: */

	rs485conf.flags &= ~(SER_RS485_RTS_AFTER_SEND);



	/* Set rts delay before send, if needed: */

	rs485conf.flags |= SER_RS485_RTS_BEFORE_SEND;

	rs485conf.delay_rts_before_send = ...;



	/* Set rts delay after send, if needed: */

	rs485conf.flags |= SER_RS485_RTS_AFTER_SEND;

	rs485conf.delay_rts_after_send = ...;



	/* Set this flag if you want to receive data even whilst sending data */

drivers/tty/serial/atmel_serial.c

+3 −13
Original line number Diff line number Diff line
@@ -228,7 +228,7 @@ void atmel_config_rs485(struct uart_port *port, struct serial_rs485 *rs485conf) 
	if (rs485conf->flags & SER_RS485_ENABLED) {

		dev_dbg(port->dev, "Setting UART to RS485\n");

		atmel_port->tx_done_mask = ATMEL_US_TXEMPTY;

		if (rs485conf->flags & SER_RS485_RTS_AFTER_SEND)

		if ((rs485conf->delay_rts_after_send) > 0)

			UART_PUT_TTGR(port, rs485conf->delay_rts_after_send);

		mode |= ATMEL_US_USMODE_RS485;

	} else {
@@ -304,7 +304,7 @@ static void atmel_set_mctrl(struct uart_port *port, u_int mctrl) 


	if (atmel_port->rs485.flags & SER_RS485_ENABLED) {

		dev_dbg(port->dev, "Setting UART to RS485\n");

		if (atmel_port->rs485.flags & SER_RS485_RTS_AFTER_SEND)

		if ((atmel_port->rs485.delay_rts_after_send) > 0)

			UART_PUT_TTGR(port,

					atmel_port->rs485.delay_rts_after_send);

		mode |= ATMEL_US_USMODE_RS485;
@@ -1228,7 +1228,7 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios *termios, 


	if (atmel_port->rs485.flags & SER_RS485_ENABLED) {

		dev_dbg(port->dev, "Setting UART to RS485\n");

		if (atmel_port->rs485.flags & SER_RS485_RTS_AFTER_SEND)

		if ((atmel_port->rs485.delay_rts_after_send) > 0)

			UART_PUT_TTGR(port,

					atmel_port->rs485.delay_rts_after_send);

		mode |= ATMEL_US_USMODE_RS485;
@@ -1447,16 +1447,6 @@ static void __devinit atmel_of_init_port(struct atmel_uart_port *atmel_port, 
		rs485conf->delay_rts_after_send = rs485_delay[1];

		rs485conf->flags = 0;



		if (rs485conf->delay_rts_before_send == 0 &&

		    rs485conf->delay_rts_after_send == 0) {

			rs485conf->flags |= SER_RS485_RTS_ON_SEND;

		} else {

			if (rs485conf->delay_rts_before_send)

				rs485conf->flags |= SER_RS485_RTS_BEFORE_SEND;

			if (rs485conf->delay_rts_after_send)

				rs485conf->flags |= SER_RS485_RTS_AFTER_SEND;

		}



		if (of_get_property(np, "rs485-rx-during-tx", NULL))

			rs485conf->flags |= SER_RS485_RX_DURING_TX;

drivers/tty/serial/crisv10.c

+2 −8
Original line number Diff line number Diff line
@@ -3234,8 +3234,7 @@ rs_write(struct tty_struct *tty, 
		e100_disable_rx(info);

		e100_enable_rx_irq(info);

#endif

		if ((info->rs485.flags & SER_RS485_RTS_BEFORE_SEND) &&

			(info->rs485.delay_rts_before_send > 0))

		if (info->rs485.delay_rts_before_send > 0)

			msleep(info->rs485.delay_rts_before_send);

	}

#endif /* CONFIG_ETRAX_RS485 */
@@ -3693,10 +3692,6 @@ rs_ioctl(struct tty_struct *tty, 


		rs485data.delay_rts_before_send = rs485ctrl.delay_rts_before_send;

		rs485data.flags = 0;

		if (rs485data.delay_rts_before_send != 0)

			rs485data.flags |= SER_RS485_RTS_BEFORE_SEND;

		else

			rs485data.flags &= ~(SER_RS485_RTS_BEFORE_SEND);



		if (rs485ctrl.enabled)

			rs485data.flags |= SER_RS485_ENABLED;
@@ -4531,7 +4526,6 @@ static int __init rs_init(void) 
		/* Set sane defaults */

		info->rs485.flags &= ~(SER_RS485_RTS_ON_SEND);

		info->rs485.flags |= SER_RS485_RTS_AFTER_SEND;

		info->rs485.flags &= ~(SER_RS485_RTS_BEFORE_SEND);

		info->rs485.delay_rts_before_send = 0;

		info->rs485.flags &= ~(SER_RS485_ENABLED);

#endif

include/linux/serial.h

+8 −6
Original line number Diff line number Diff line
@@ -207,13 +207,15 @@ struct serial_icounter_struct { 


struct serial_rs485 {

	__u32	flags;			/* RS485 feature flags */

#define SER_RS485_ENABLED		(1 << 0)

#define SER_RS485_RTS_ON_SEND		(1 << 1)

#define SER_RS485_RTS_AFTER_SEND	(1 << 2)

#define SER_RS485_RTS_BEFORE_SEND	(1 << 3)

#define SER_RS485_ENABLED		(1 << 0)	/* If enabled */

#define SER_RS485_RTS_ON_SEND		(1 << 1)	/* Logical level for

							   RTS pin when

							   sending */

#define SER_RS485_RTS_AFTER_SEND	(1 << 2)	/* Logical level for

							   RTS pin after sent*/

#define SER_RS485_RX_DURING_TX		(1 << 4)

	__u32	delay_rts_before_send;	/* Milliseconds */

	__u32	delay_rts_after_send;	/* Milliseconds */

	__u32	delay_rts_before_send;	/* Delay before send (milliseconds) */

	__u32	delay_rts_after_send;	/* Delay after send (milliseconds) */

	__u32	padding[5];		/* Memory is cheap, new structs

					   are a royal PITA .. */

};

CRA Git | Maintained and supported by SUSTech CRA and CCSE