Refactor divisor register programming into a new function, serial8250_set_divisor; this allows serial console to reinitialize early after resume from suspend.
Signed-off-by: Peter Hurley <[email protected]> --- drivers/tty/serial/8250/8250_core.c | 87 ++++++++++++++++++++----------------- 1 file changed, 48 insertions(+), 39 deletions(-) diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c index 77afa5f..b8aa6ef 100644 --- a/drivers/tty/serial/8250/8250_core.c +++ b/drivers/tty/serial/8250/8250_core.c @@ -2455,6 +2455,50 @@ static unsigned char serial8250_compute_lcr(struct uart_8250_port *up, return cval; } +void serial8250_set_divisor(struct uart_port *port, unsigned int baud, + unsigned int quot) +{ + struct uart_8250_port *up = up_to_u8250p(port); + + /* Workaround to enable 115200 baud on OMAP1510 internal ports */ + if (is_omap1510_8250(up)) { + if (baud == 115200) { + quot = 1; + serial_port_out(port, UART_OMAP_OSC_12M_SEL, 1); + } else + serial_port_out(port, UART_OMAP_OSC_12M_SEL, 0); + } + + /* + * For NatSemi, switch to bank 2 not bank 1, to avoid resetting EXCR2, + * otherwise just set DLAB + */ + if (up->capabilities & UART_NATSEMI) + serial_port_out(port, UART_LCR, 0xe0); + else + serial_port_out(port, UART_LCR, up->lcr | UART_LCR_DLAB); + + serial_dl_write(up, quot); + + /* + * XR17V35x UARTs have an extra fractional divisor register (DLD) + * + * We need to recalculate all of the registers, because DLM and DLL + * are already rounded to a whole integer. + * + * When recalculating we use a 32x clock instead of a 16x clock to + * allow 1-bit for rounding in the fractional part. + */ + if (up->port.type == PORT_XR17V35X) { + unsigned int baud_x32 = (port->uartclk * 2) / baud; + u16 quot = baud_x32 / 32; + u8 quot_frac = DIV_ROUND_CLOSEST(baud_x32 % 32, 2); + + serial_dl_write(up, quot); + serial_port_out(port, 0x2, quot_frac & 0xf); + } +} + void serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios, struct ktermios *old) @@ -2503,6 +2547,8 @@ serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios, serial8250_rpm_get(up); spin_lock_irqsave(&port->lock, flags); + up->lcr = cval; /* Save computed LCR */ + /* * Update the per-port timeout. */ @@ -2567,43 +2613,7 @@ serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios, serial_port_out(port, UART_EFR, efr); } - /* Workaround to enable 115200 baud on OMAP1510 internal ports */ - if (is_omap1510_8250(up)) { - if (baud == 115200) { - quot = 1; - serial_port_out(port, UART_OMAP_OSC_12M_SEL, 1); - } else - serial_port_out(port, UART_OMAP_OSC_12M_SEL, 0); - } - - /* - * For NatSemi, switch to bank 2 not bank 1, to avoid resetting EXCR2, - * otherwise just set DLAB - */ - if (up->capabilities & UART_NATSEMI) - serial_port_out(port, UART_LCR, 0xe0); - else - serial_port_out(port, UART_LCR, cval | UART_LCR_DLAB); - - serial_dl_write(up, quot); - - /* - * XR17V35x UARTs have an extra fractional divisor register (DLD) - * - * We need to recalculate all of the registers, because DLM and DLL - * are already rounded to a whole integer. - * - * When recalculating we use a 32x clock instead of a 16x clock to - * allow 1-bit for rounding in the fractional part. - */ - if (up->port.type == PORT_XR17V35X) { - unsigned int baud_x32 = (port->uartclk * 2) / baud; - u16 quot = baud_x32 / 32; - u8 quot_frac = DIV_ROUND_CLOSEST(baud_x32 % 32, 2); - - serial_dl_write(up, quot); - serial_port_out(port, 0x2, quot_frac & 0xf); - } + serial8250_set_divisor(port, baud, quot); /* * LCR DLAB must be set to enable 64-byte FIFO mode. If the FCR @@ -2612,8 +2622,7 @@ serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios, if (port->type == PORT_16750) serial_port_out(port, UART_FCR, up->fcr); - serial_port_out(port, UART_LCR, cval); /* reset DLAB */ - up->lcr = cval; /* Save LCR */ + serial_port_out(port, UART_LCR, up->lcr); /* reset DLAB */ if (port->type != PORT_16750) { /* emulated UARTs (Lucent Venus 167x) need two steps */ if (up->fcr & UART_FCR_ENABLE_FIFO) -- 2.2.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
