[PATCH] dz: Clean up and improve the setup of termios settings

From: Maciej W. Rozycki
Date: Tue Oct 23 2007 - 10:25:21 EST


A set of changes to the way termios settings are propagated to the serial
port hardware. The DZ11 only supports a selection of fixed baud settings,
so some requests may not be fulfilled. Keep the old setting in such a
case and failing that resort to 9600bps. Also add a missing update of the
transmit timeout. And remove the explicit encoding of the line selected
from writes to the Line Parameters Register as it has been preencoded by
the ->set_termios() call already. Finally, remove a duplicate macro for
the Receiver Enable bit.

Signed-off-by: Maciej W. Rozycki <macro@xxxxxxxxxxxxxx>
---
Tested with checkpatch.pl and at the run-time -- MIPS/Linux on a
DECstation 5000/200.

Please apply,

Maciej

patch-mips-2.6.23-rc5-20070904-dz-termios-8
diff -up --recursive --new-file linux-mips-2.6.23-rc5-20070904.macro/drivers/serial/dz.c linux-mips-2.6.23-rc5-20070904/drivers/serial/dz.c
--- linux-mips-2.6.23-rc5-20070904.macro/drivers/serial/dz.c 2007-10-13 20:10:37.000000000 +0000
+++ linux-mips-2.6.23-rc5-20070904/drivers/serial/dz.c 2007-10-23 14:09:24.000000000 +0000
@@ -125,8 +125,8 @@ static void dz_stop_rx(struct uart_port
{
struct dz_port *dport = (struct dz_port *)uport;

- dport->cflag &= ~DZ_CREAD;
- dz_out(dport, DZ_LPR, dport->cflag | dport->port.line);
+ dport->cflag &= ~DZ_RXENAB;
+ dz_out(dport, DZ_LPR, dport->cflag);
}

static void dz_enable_ms(struct uart_port *port)
@@ -461,12 +461,51 @@ static void dz_break_ctl(struct uart_por
spin_unlock_irqrestore(&uport->lock, flags);
}

+static int dz_encode_baud_rate(unsigned int baud)
+{
+ switch (baud) {
+ case 50:
+ return DZ_B50;
+ case 75:
+ return DZ_B75;
+ case 110:
+ return DZ_B110;
+ case 134:
+ return DZ_B134;
+ case 150:
+ return DZ_B150;
+ case 300:
+ return DZ_B300;
+ case 600:
+ return DZ_B600;
+ case 1200:
+ return DZ_B1200;
+ case 1800:
+ return DZ_B1800;
+ case 2000:
+ return DZ_B2000;
+ case 2400:
+ return DZ_B2400;
+ case 3600:
+ return DZ_B3600;
+ case 4800:
+ return DZ_B4800;
+ case 7200:
+ return DZ_B7200;
+ case 9600:
+ return DZ_B9600;
+ default:
+ return -1;
+ }
+}
+
static void dz_set_termios(struct uart_port *uport, struct ktermios *termios,
struct ktermios *old_termios)
{
struct dz_port *dport = (struct dz_port *)uport;
unsigned long flags;
unsigned int cflag, baud;
+ int bflag;

cflag = dport->port.line;

@@ -493,60 +532,26 @@ static void dz_set_termios(struct uart_p
cflag |= DZ_PARODD;

baud = uart_get_baud_rate(uport, termios, old_termios, 50, 9600);
- switch (baud) {
- case 50:
- cflag |= DZ_B50;
- break;
- case 75:
- cflag |= DZ_B75;
- break;
- case 110:
- cflag |= DZ_B110;
- break;
- case 134:
- cflag |= DZ_B134;
- break;
- case 150:
- cflag |= DZ_B150;
- break;
- case 300:
- cflag |= DZ_B300;
- break;
- case 600:
- cflag |= DZ_B600;
- break;
- case 1200:
- cflag |= DZ_B1200;
- break;
- case 1800:
- cflag |= DZ_B1800;
- break;
- case 2000:
- cflag |= DZ_B2000;
- break;
- case 2400:
- cflag |= DZ_B2400;
- break;
- case 3600:
- cflag |= DZ_B3600;
- break;
- case 4800:
- cflag |= DZ_B4800;
- break;
- case 7200:
- cflag |= DZ_B7200;
- break;
- case 9600:
- default:
- cflag |= DZ_B9600;
+ bflag = dz_encode_baud_rate(baud);
+ if (bflag < 0) { /* Try to keep unchanged. */
+ baud = uart_get_baud_rate(uport, old_termios, NULL, 50, 9600);
+ bflag = dz_encode_baud_rate(baud);
+ if (bflag < 0) { /* Resort to 9600. */
+ baud = 9600;
+ bflag = DZ_B9600;
+ }
+ tty_termios_encode_baud_rate(termios, baud, baud);
}
+ cflag |= bflag;

if (termios->c_cflag & CREAD)
cflag |= DZ_RXENAB;

spin_lock_irqsave(&dport->port.lock, flags);

- dz_out(dport, DZ_LPR, cflag | dport->port.line);
+ uart_update_timeout(uport, termios->c_cflag, baud);
+
+ dz_out(dport, DZ_LPR, cflag);
dport->cflag = cflag;

/* setup accept flag */
diff -up --recursive --new-file linux-mips-2.6.23-rc5-20070904.macro/drivers/serial/dz.h linux-mips-2.6.23-rc5-20070904/drivers/serial/dz.h
--- linux-mips-2.6.23-rc5-20070904.macro/drivers/serial/dz.h 2007-02-05 16:38:50.000000000 +0000
+++ linux-mips-2.6.23-rc5-20070904/drivers/serial/dz.h 2007-10-13 17:27:11.000000000 +0000
@@ -107,8 +107,8 @@
#define DZ_B7200 0x0D00
#define DZ_B9600 0x0E00

-#define DZ_CREAD 0x1000 /* Enable receiver */
-#define DZ_RXENAB 0x1000 /* enable receive char */
+#define DZ_RXENAB 0x1000 /* Receiver Enable */
+
/*
* Addresses for the DZ registers
*/
-
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