Hi Matthias, On Friday 19 December 2008 00:48:34 Matthias Fuchs wrote: > Hi, > > please see my patch for enabling the RS485 half-duplex control below. > Please note that I am using this on a PowerPC platform. So I needed to > add the ioctl to the PowerPC header. As Wolfgang stated, it is > already in the x86 header. I am not sure if I have to post the modification > on the powerpc header to the PowerPC list or if it will be accepted here > as well. .... But first I will have to see what you think of this patch > :-) > > Matthias > > > Some Exar UARTs support a auto rs485 mode. In this mode > the UART's RTS# pin is activated during transmitting and > can be used to enable a rs485 line driver. This has nothing > to do with attempts to do this by manually by asserting/ > deasserting handshake lines. [snip] > + serial_outp(up, UART_LCR, 0xbf); > + fctr = serial_inp(up, UART_FCTR); > + if (rs485ctrl.flags & SER_RS485_ENABLED) > + fctr |= 0x08; > + else > + fctr &= ~0x08; > + serial_outp(up, UART_FCTR, fctr); > + serial_outp(up, UART_LCR, 0); You might also want to add a #define UART_FCTR_RS485 0x08 to include/linux/serial_reg.h instead of using a hardcoded 0x08 constant. -- Laurent Pinchart CSE Semaphore Belgium Chaussee de Bruxelles, 732A B-1410 Waterloo Belgium T +32 (2) 387 42 59 F +32 (2) 387 42 75 -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
