Hi Alan, Hi Greg,
it seems that the crisv10.c and the atmel_serial.c serial
drivers interpret the fields of the serial_rs485 structure in a different
way.
In particular, it seems that crisv10.c uses SER_RS485_RTS_AFTER_SEND and
SER_RS485_RTS_ON_SEND for the _logic value_ 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.
In particular, SER_RS485_RTS_AFTER_SEND and SER_RS485_RTS_ON_SEND will
be used to set the logic value of the RTS pin (as in the crisv10.c
driver); the delay is understood by looking only at the value of
delay_rts_before_send and delay_rts_after_send.
Best regards,
Claudio
Subject: RS485: fix inconsistencies in the meaning of some variables
From: Claudio Scordino <claudio@xxxxxxxxxxxxxxx>
The crisv10.c and the atmel_serial.c serial drivers interpret 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: Claudio Scordino <claudio@xxxxxxxxxxxxxxx>
Signed-off-by: Darron Black <darron@xxxxxxxxxxx>
---
Documentation/serial/serial-rs485.txt | 14 +++++++++++---
drivers/tty/serial/atmel_serial.c | 20 +++++---------------
drivers/tty/serial/crisv10.c | 10 ++--------
include/linux/serial.h | 14 ++++++++------
4 files changed, 26 insertions(+), 32 deletions(-)
diff --git a/Documentation/serial/serial-rs485.txt b/Documentation/serial/serial-rs485.txt
index 079cb3d..d3a7388 100644
--- a/Documentation/serial/serial-rs485.txt
+++ b/Documentation/serial/serial-rs485.txt
@@ -97,15 +97,23 @@
struct serial_rs485 rs485conf;
- /* Set RS485 mode: */
+ /* Enable RS485 mode: */
rs485conf.flags |= SER_RS485_ENABLED;
+ /* Set voltage value for RTS pin equal to 1 when sending: */
+ rs485conf.flags |= SER_RS485_RTS_ON_SEND;
+ /* or, set voltage value for RTS pin equal to 0 when sending: */
+ rs485conf.flags &= ~(SER_RS485_RTS_ON_SEND);
+
+ /* Set voltage value for RTS pin equal to 1 after sending: */
+ rs485conf.flags |= SER_RS485_RTS_AFTER_SEND;
+ /* or, set voltage value 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 */
diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
index 4a0f86f..23aa677 100644
--- a/drivers/tty/serial/atmel_serial.c
+++ b/drivers/tty/serial/atmel_serial.c
@@ -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 {
@@ -304,9 +304,9 @@ 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);
+ atmel_port->rs485.delay_rts_after_send);
mode |= ATMEL_US_USMODE_RS485;
} else {
dev_dbg(port->dev, "Setting UART to RS232\n");
@@ -1228,9 +1228,9 @@ 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);
+ atmel_port->rs485.delay_rts_after_send);
mode |= ATMEL_US_USMODE_RS485;
} else {
dev_dbg(port->dev, "Setting UART to RS232\n");
@@ -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;
diff --git a/drivers/tty/serial/crisv10.c b/drivers/tty/serial/crisv10.c
index b743504..1dfba7b 100644
--- a/drivers/tty/serial/crisv10.c
+++ b/drivers/tty/serial/crisv10.c
@@ -3234,9 +3234,8 @@ 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))
- msleep(info->rs485.delay_rts_before_send);
+ 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
diff --git a/include/linux/serial.h b/include/linux/serial.h
index 97ff8e2..5a9fd4a 100644
--- a/include/linux/serial.h
+++ b/include/linux/serial.h
@@ -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) /* Voltage value for
+ RTS pin when
+ sending */
+#define SER_RS485_RTS_AFTER_SEND (1 << 2) /* Voltage value 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 .. */
};
--
1.7.1
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