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Commit 1fe8aa88 authored by Russell King's avatar Russell King
Browse files

SERIAL: omap: don't read back LCR/MCR/EFR 



There's really no reason to read back these registers while setting
the termios modes, provided we keep our cached copies up to date.
Remove these readbacks.

This has the benefit that we know that the EFR_ECB and MCR_TCRTLR
bits will always be clear, so we don't need to keep masking these
bits throughout the code.

Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent 01d70bb3

drivers/tty/serial/omap-serial.c

+6 −7
Original line number Diff line number Diff line
@@ -912,8 +912,11 @@ serial_omap_set_termios(struct uart_port *port, struct ktermios *termios, 
		/* Enable AUTORTS and AUTOCTS */

		up->efr |= UART_EFR_CTS | UART_EFR_RTS;



		/* Ensure MCR RTS is asserted */

		up->mcr |= UART_MCR_RTS;



		/* Disable access to TCR/TLR */

		serial_out(up, UART_MCR, up->mcr | UART_MCR_RTS);

		serial_out(up, UART_MCR, up->mcr);

		serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);

		serial_out(up, UART_EFR, up->efr);

		serial_out(up, UART_LCR, cval);
@@ -928,10 +931,8 @@ serial_omap_set_termios(struct uart_port *port, struct ktermios *termios, 


	/* Software Flow Control Configuration */

	if (up->port.flags & UPF_SOFT_FLOW) {

		up->lcr = serial_in(up, UART_LCR);

		serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);

		up->efr = serial_in(up, UART_EFR);

		serial_out(up, UART_EFR, up->efr & ~UART_EFR_ECB);

		serial_out(up, UART_EFR, up->efr);



		serial_out(up, UART_XON1, termios->c_cc[VSTART]);

		serial_out(up, UART_XOFF1, termios->c_cc[VSTOP]);
@@ -958,8 +959,6 @@ serial_omap_set_termios(struct uart_port *port, struct ktermios *termios, 
		serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);

		serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);



		up->mcr = serial_in(up, UART_MCR);



		/*

		 * IXANY Flag:

		 * Enable any character to restart output.
@@ -975,7 +974,7 @@ serial_omap_set_termios(struct uart_port *port, struct ktermios *termios, 
		serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);

		serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG);

		serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);

		serial_out(up, UART_MCR, up->mcr & ~UART_MCR_TCRTLR);

		serial_out(up, UART_MCR, up->mcr);

		serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);

		serial_out(up, UART_EFR, up->efr);

		serial_out(up, UART_LCR, up->lcr);