|
您好!tronlong提供的最新的linux3.3内核已经对uart0和uart1做了rs485功能的支持,uart2默认为启动串口。如何想使能uart0和uart1 rs485的功能,只需在menuconfig将485使能。6 z v+ W# c5 x' z# @
*** DaVinci Core Type *** | |
) Y1 Q6 Z- T7 Q) s- Y% A# S | | [ ] DaVinci 644x based system | |
A& }5 k2 I6 [7 _ | | [ ] DaVinci 355 based system | |6 p# a1 m6 G) z/ y+ j6 \, G. K2 r
| | [ ] DaVinci 646x based system | |
2 K" K! L% }" h1 T+ ^ | | [ ] DA830/OMAP-L137/AM17x based system | |
3 c& @& C. b% v7 V" X2 C | | [*] DA850/OMAP-L138/AM18x based system | | c2 d5 V6 [2 X5 {% A# E% v3 F
| | [ ] Enable UART1 flow control | |
/ \/ f1 b' i/ ~* r6 B/ q; N% C | | [ ] Enable UART0 RS485 funcation | |0 e$ @9 @2 S/ q$ `
| | [*] Enable UART1 RS485 funcation
$ N& b: A9 j6 i
4 R, M. r# }0 F d4 Y想了解详细的功能实现,也可以查看8250.c文件里面的;+ G5 @3 Q* x u5 y2 h7 e
void serial8250_tx_chars(struct uart_8250_port *up)+ i* E, ~' Z0 o( z3 p0 u4 m
return;
9 d9 C! A4 {4 B } l* J7 {+ d& u7 t
- t$ A5 M1 y: }+#if 1# H2 d$ r1 j, M; D1 c" `5 o
+ /* The funcation with RS485 flow control */6 `0 Z+ M+ a# S
+ if (up->port.private_data) {6 @0 N) G0 c: t% z' G# o" o
+ struct serial8250_flow_ctrl *flow_ctrl_p;" f# c" Y+ Y& d
+ flow_ctrl_p = up->port.private_data;
" z5 S6 b+ o. Z- j# V0 R+/ t) S0 o0 l- o4 F
+ if (flow_ctrl_p->gpio) {- x- N, R! H q9 N! a1 a1 a+ ^
+ gpio_set_value(flow_ctrl_p->gpio, 1);- |3 w4 Y2 _0 B4 E9 b
+ ndelay(50); /* Propagation delay >= 50ns */( J- g8 ~* V6 ` d) m
+ }
6 k J0 z0 O8 `7 R5 b4 T# T6 G1 b+ }3 t! J7 z2 @% O6 D
+#endif0 J' `4 _7 q" i0 N+ }; r; ]
希望对您有帮助。: G7 e7 O( h" ^% m' o4 j3 C
|
|