[PATCH v4 16/28] tty: serial: owl: Implement console driver

Am 06.06.2017 um 15:34 schrieb Alan Cox:

quoted

+static void owl_uart_set_termios(struct uart_port *port,
+				 struct ktermios *termios,
+				 struct ktermios *old)
+{
+	struct owl_uart_port *owl_port = to_owl_uart_port(port);
+	unsigned int baud;
+	u32 ctl;
+	unsigned long flags;
+
+	spin_lock_irqsave(&port->lock, flags);
+
+	/* We don't support modem control lines. */
+	termios->c_cflag &= ~(HUPCL | CMSPAR);
+	termios->c_cflag |= CLOCAL;

CLOCAL and HUPCL are software not hardware properties so are probably
best not forced (it'll confuse some apps if you do)

quoted

+
+	/* We don't support BREAK character recognition. */
+	termios->c_iflag &= ~(IGNBRK | BRKINT);

Ditto these

Fixed. These were obviously forward-ported from the vendor tree.

https://github.com/LeMaker/linux-actions/blob/linux-3.10.y/arch/arm/mach-owl/serial-owl.c

You do clear CMSPAR which is right if not supported but then later on we
have:

quoted

+	if (termios->c_cflag & PARENB) {
+		if (termios->c_cflag & CMSPAR) {
+			if (termios->c_cflag & PARODD)
+				ctl |= OWL_UART_CTL_PRS_MARK;
+			else
+				ctl |= OWL_UART_CTL_PRS_SPACE;
+		} else if (termios->c_cflag & PARODD)
+			ctl |= OWL_UART_CTL_PRS_ODD;
+		else
+			ctl |= OWL_UART_CTL_PRS_EVEN;
+	} else
+		ctl |= OWL_UART_CTL_PRS_NONE;

Which seems to indicate you do support CMSPAR so shouldn't be clearing it.

Again that's what the original code was like.

Since these register values do exist, I would rather not rip the code
out, unless it's wrong. In my testing, not clearing CMSPAR works so far.

quoted

+	baud = uart_get_baud_rate(port, termios, old, 9600, 3200000);
+	owl_uart_change_baudrate(owl_port, baud);

You should re-encode the resulting baud rate into the termios

        /* Don't rewrite B0 */
        if (tty_termios_baud_rate(termios))
                tty_termios_encode_baud_rate(termios, baud, baud);

Added, thanks.

Regards,
Andreas

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