diff options
| -rw-r--r-- | Documentation/driver-api/serial/serial-rs485.rst | 13 | ||||
| -rw-r--r-- | include/uapi/linux/serial.h | 55 |
2 files changed, 43 insertions, 25 deletions
diff --git a/Documentation/driver-api/serial/serial-rs485.rst b/Documentation/driver-api/serial/serial-rs485.rst index 6ebad75c74ed..264e4b753713 100644 --- a/Documentation/driver-api/serial/serial-rs485.rst +++ b/Documentation/driver-api/serial/serial-rs485.rst @@ -29,11 +29,11 @@ RS485 Serial Communications 3. Data Structures Already Available in the Kernel ================================================== - The Linux kernel provides the serial_rs485 structure (see [1]) to handle - RS485 communications. This data structure is used to set and configure RS485 + The Linux kernel provides the serial_rs485 structure to handle 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] + The device tree can also provide RS485 boot time parameters (see [1] for bindings). The driver is in charge of filling this data structure from the values given by the device tree. @@ -47,6 +47,9 @@ RS485 Serial Communications for the uart_port. TIOCGRS485 ioctl can be used to read back the serial_rs485 structure matching to the current configuration. +.. kernel-doc:: include/uapi/linux/serial.h + :identifiers: serial_rs485 + 4. Usage from user-level ======================== @@ -126,6 +129,4 @@ RS485 Serial Communications 6. References ============= - [1] include/uapi/linux/serial.h - - [2] Documentation/devicetree/bindings/serial/rs485.txt + [1] Documentation/devicetree/bindings/serial/rs485.txt diff --git a/include/uapi/linux/serial.h b/include/uapi/linux/serial.h index cea06924b295..53bc1af67a41 100644 --- a/include/uapi/linux/serial.h +++ b/include/uapi/linux/serial.h @@ -107,33 +107,50 @@ struct serial_icounter_struct { int reserved[9]; }; -/* +/** + * struct serial_rs485 - serial interface for controlling RS485 settings. + * @flags: RS485 feature flags. + * @delay_rts_before_send: Delay before send (milliseconds). + * @delay_rts_after_send: Delay after send (milliseconds). + * @addr_recv: Receive filter for RS485 addressing mode + * (used only when %SER_RS485_ADDR_RECV is set). + * @addr_dest: Destination address for RS485 addressing mode + * (used only when %SER_RS485_ADDR_DEST is set). + * @padding0: Padding (set to zero). + * @padding1: Padding (set to zero). + * @padding: Deprecated, use @padding0 and @padding1 instead. + * Do not use with @addr_recv and @addr_dest (due to + * overlap). + * * Serial interface for controlling RS485 settings on chips with suitable * support. Set with TIOCSRS485 and get with TIOCGRS485 if supported by your * platform. The set function returns the new state, with any unsupported bits * reverted appropriately. + * + * The flag bits are: + * + * * %SER_RS485_ENABLED - RS485 enabled. + * * %SER_RS485_RTS_ON_SEND - Logical level for RTS pin when sending. + * * %SER_RS485_RTS_AFTER_SEND - Logical level for RTS pin after sent. + * * %SER_RS485_RX_DURING_TX - Full-duplex RS485 line. + * * %SER_RS485_TERMINATE_BUS - Enable bus termination (if supported). + * * %SER_RS485_ADDRB - Enable RS485 addressing mode. + * * %SER_RS485_ADDR_RECV - Receive address filter (enables @addr_recv). Requires %SER_RS485_ADDRB. + * * %SER_RS485_ADDR_DEST - Destination address (enables @addr_dest). Requires %SER_RS485_ADDRB. */ - struct serial_rs485 { - __u32 flags; /* RS485 feature flags */ -#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*/ + __u32 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_RX_DURING_TX (1 << 4) -#define SER_RS485_TERMINATE_BUS (1 << 5) /* Enable bus - termination - (if supported) */ - -/* RS-485 addressing mode */ -#define SER_RS485_ADDRB (1 << 6) /* Enable addressing mode */ -#define SER_RS485_ADDR_RECV (1 << 7) /* Receive address filter */ -#define SER_RS485_ADDR_DEST (1 << 8) /* Destination address */ +#define SER_RS485_TERMINATE_BUS (1 << 5) +#define SER_RS485_ADDRB (1 << 6) +#define SER_RS485_ADDR_RECV (1 << 7) +#define SER_RS485_ADDR_DEST (1 << 8) - __u32 delay_rts_before_send; /* Delay before send (milliseconds) */ - __u32 delay_rts_after_send; /* Delay after send (milliseconds) */ + __u32 delay_rts_before_send; + __u32 delay_rts_after_send; /* The fields below are defined by flags */ union { |