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: Russell King <rmk+kernel@arm.linux.org.uk>
This commit is contained in:
Russell King 2012-10-06 09:04:03 +01:00
parent 01d70bb37c
commit 1fe8aa8803

View File

@ -912,8 +912,11 @@ serial_omap_set_termios(struct uart_port *port, struct ktermios *termios,
/* Enable AUTORTS and AUTOCTS */ /* Enable AUTORTS and AUTOCTS */
up->efr |= UART_EFR_CTS | UART_EFR_RTS; up->efr |= UART_EFR_CTS | UART_EFR_RTS;
/* Ensure MCR RTS is asserted */
up->mcr |= UART_MCR_RTS;
/* Disable access to TCR/TLR */ /* 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_LCR, UART_LCR_CONF_MODE_B);
serial_out(up, UART_EFR, up->efr); serial_out(up, UART_EFR, up->efr);
serial_out(up, UART_LCR, cval); 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 */ /* Software Flow Control Configuration */
if (up->port.flags & UPF_SOFT_FLOW) { if (up->port.flags & UPF_SOFT_FLOW) {
up->lcr = serial_in(up, UART_LCR);
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
up->efr = serial_in(up, UART_EFR); serial_out(up, UART_EFR, up->efr);
serial_out(up, UART_EFR, up->efr & ~UART_EFR_ECB);
serial_out(up, UART_XON1, termios->c_cc[VSTART]); serial_out(up, UART_XON1, termios->c_cc[VSTART]);
serial_out(up, UART_XOFF1, termios->c_cc[VSTOP]); 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_EFR, up->efr | UART_EFR_ECB);
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A); serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
up->mcr = serial_in(up, UART_MCR);
/* /*
* IXANY Flag: * IXANY Flag:
* Enable any character to restart output. * 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_LCR, UART_LCR_CONF_MODE_B);
serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG); serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG);
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A); 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_LCR, UART_LCR_CONF_MODE_B);
serial_out(up, UART_EFR, up->efr); serial_out(up, UART_EFR, up->efr);
serial_out(up, UART_LCR, up->lcr); serial_out(up, UART_LCR, up->lcr);