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authorClaudio Scordino <claudio@evidence.eu.com>2011-11-09 18:51:49 +0400
committerGreg Kroah-Hartman <gregkh@suse.de>2011-11-16 00:13:44 +0400
commit93f3350c46fa5dfcc9650eb19b186e71ffc924c3 (patch)
tree13b6f81f9fd85227283b38af6267d094e0038beb /Documentation/serial/serial-rs485.txt
parent90f04c2926cfb5bf74533b0a7766bc896f6a0c0e (diff)
downloadlinux-93f3350c46fa5dfcc9650eb19b186e71ffc924c3.tar.xz
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: Claudio Scordino <claudio@evidence.eu.com> Signed-off-by: Darron Black <darron@griffin.net> Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com> Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'Documentation/serial/serial-rs485.txt')
-rw-r--r--Documentation/serial/serial-rs485.txt14
1 files changed, 11 insertions, 3 deletions
diff --git a/Documentation/serial/serial-rs485.txt b/Documentation/serial/serial-rs485.txt
index 079cb3df62cf..41c8378c0b2f 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 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 */