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| author | Dmitry Torokhov <dmitry.torokhov@gmail.com> | 2012-01-08 23:38:23 -0800 |
|---|---|---|
| committer | Dmitry Torokhov <dmitry.torokhov@gmail.com> | 2012-01-08 23:38:23 -0800 |
| commit | da733563be5a9da26fe81d9f007262d00b846e22 (patch) | |
| tree | db28291df94a2043af2123911984c5c173da4e6f /Documentation/serial/serial-rs485.txt | |
| parent | 6ccbcf2cb41131f8d56ef0723bf3f7c1f8486076 (diff) | |
| parent | dab78d7924598ea4031663dd10db814e2e324928 (diff) | |
| download | op-kernel-dev-da733563be5a9da26fe81d9f007262d00b846e22.zip op-kernel-dev-da733563be5a9da26fe81d9f007262d00b846e22.tar.gz | |
Merge branch 'next' into for-linus
Diffstat (limited to 'Documentation/serial/serial-rs485.txt')
| -rw-r--r-- | Documentation/serial/serial-rs485.txt | 22 |
1 files changed, 19 insertions, 3 deletions
diff --git a/Documentation/serial/serial-rs485.txt b/Documentation/serial/serial-rs485.txt index a493238..41c8378 100644 --- a/Documentation/serial/serial-rs485.txt +++ b/Documentation/serial/serial-rs485.txt @@ -28,6 +28,10 @@ RS485 communications. This data structure is used to set and configure RS485 parameters in the platform data and in ioctls. + The device tree can also provide RS485 boot time parameters (see [2] + for bindings). The driver is in charge of filling this data structure from + the values given by the device tree. + Any driver for devices capable of working both as RS232 and RS485 should provide at least the following ioctls: @@ -93,17 +97,28 @@ 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 */ + rs485conf.flags |= SER_RS485_RX_DURING_TX; + if (ioctl (fd, TIOCSRS485, &rs485conf) < 0) { /* Error handling. See errno. */ } @@ -118,3 +133,4 @@ 5. REFERENCES [1] include/linux/serial.h + [2] Documentation/devicetree/bindings/serial/rs485.txt |
