About the flags names -- CARTS, UART_FCTR_RS485 May I suggest CRTSTOGGLE since it is known by that kind of name in other OS's :-) And further, it says was RTS will do, instead of why. Maybe someone could use it for something other than RS485 ? Regards JP Tosoni > -----Original Message----- > From: linux-serial-owner@xxxxxxxxxxxxxxx > [mailto:linux-serial-owner@xxxxxxxxxxxxxxx]On Behalf Of > Laurent Pinchart > Sent: Thursday, July 24, 2008 1:47 PM > To: linux-serial@xxxxxxxxxxxxxxx > Cc: Alan Cox; rmk@xxxxxxxxxxxxxxxx > Subject: [PATCH/RFC] 8250: Auto RS485 direction control > > > This patch adds support for the automatic RS485 direction > control feature > present in 16850 UARTs. > > A new termios c_cflag, CARTS, is introduced to configure > automatic direction > control from userspace. > > This is a first proposal. I'm open to suggestions regarding > the CARTS name. > I assume the CARTS flag will have to be added to all > asm/termbits.h headers. > Why are the termios bits definitions platform specific ? > > --- > drivers/serial/8250.c | 14 ++++++++++++++ > include/asm-powerpc/termbits.h | 1 + > include/linux/serial_reg.h | 1 + > 3 files changed, 16 insertions(+), 0 deletions(-) > > diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c > index 62a2e49..a1351d5 100644 > --- a/drivers/serial/8250.c > +++ b/drivers/serial/8250.c > @@ -2071,6 +2071,20 @@ serial8250_set_termios(struct > uart_port *port, struct ktermios *termios, > if (up->port.type == PORT_16750) > serial_outp(up, UART_FCR, fcr); > > +#ifdef CARTS > + /* Auto RS485 Direction Control on 16850 UARTs */ > + if (up->port.type == PORT_16850) { > + unsigned char fctr; > + > + serial_outp(up, UART_LCR, 0xbf); > + fctr = serial_inp(up, UART_FCTR) & ~UART_FCTR_RS485; > + if (termios->c_cflag & CARTS) > + fctr |= UART_FCTR_RS485; > + serial_outp(up, UART_FCTR, fctr); > + serial_outp(up, UART_LCR, 0); > + } > +#endif > + > serial_outp(up, UART_LCR, cval); /* reset DLAB */ > up->lcr = cval; /* Save LCR */ > if (up->port.type != PORT_16750) { > diff --git a/include/asm-powerpc/termbits.h > b/include/asm-powerpc/termbits.h > index 5e79198..7b7ee27 100644 > --- a/include/asm-powerpc/termbits.h > +++ b/include/asm-powerpc/termbits.h > @@ -166,6 +166,7 @@ struct ktermios { > #define HUPCL 00040000 > > #define CLOCAL 00100000 > +#define CARTS 004000000000 /* auto RTS control */ > #define CMSPAR 010000000000 /* mark or > space (stick) parity */ > #define CRTSCTS 020000000000 /* flow control */ > > diff --git a/include/linux/serial_reg.h b/include/linux/serial_reg.h > index 3c8a6aa..3db78cc 100644 > --- a/include/linux/serial_reg.h > +++ b/include/linux/serial_reg.h > @@ -188,6 +188,7 @@ > #define UART_FCTR_RTS_8DELAY 0x03 > #define UART_FCTR_IRDA 0x04 /* IrDa data > encode select */ > #define UART_FCTR_TX_INT 0x08 /* Tx interrupt type select */ > +#define UART_FCTR_RS485 0x08 /* Auto RS485 > direction control */ > #define UART_FCTR_TRGA 0x00 /* Tx/Rx 550 > trigger table select */ > #define UART_FCTR_TRGB 0x10 /* Tx/Rx 650 > trigger table select */ > #define UART_FCTR_TRGC 0x20 /* Tx/Rx 654 > trigger table select */ > -- > 1.5.0 > > -- > 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
