From 3f6b3ce071d3a3632c82b53077d21f5beab3a4aa Mon Sep 17 00:00:00 2001 From: Peter Hurley Date: Sun, 10 Jan 2016 14:39:31 -0800 Subject: [PATCH] serial: 8250: Refactor serial8250_rx_chars() inner loop Factor the read/process one char inner loop to a separate helper function serial8250_read_char(). No functional change. Signed-off-by: Peter Hurley Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/8250/8250_port.c | 120 ++++++++++++++-------------- 1 file changed, 62 insertions(+), 58 deletions(-) diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c index 8d262bce97e4..7580d713cde5 100644 --- a/drivers/tty/serial/8250/8250_port.c +++ b/drivers/tty/serial/8250/8250_port.c @@ -1412,6 +1412,67 @@ static void serial8250_enable_ms(struct uart_port *port) serial8250_rpm_put(up); } +static void serial8250_read_char(struct uart_8250_port *up, unsigned char lsr) +{ + struct uart_port *port = &up->port; + unsigned char ch; + char flag = TTY_NORMAL; + + if (likely(lsr & UART_LSR_DR)) + ch = serial_in(up, UART_RX); + else + /* + * Intel 82571 has a Serial Over Lan device that will + * set UART_LSR_BI without setting UART_LSR_DR when + * it receives a break. To avoid reading from the + * receive buffer without UART_LSR_DR bit set, we + * just force the read character to be 0 + */ + ch = 0; + + port->icount.rx++; + + lsr |= up->lsr_saved_flags; + up->lsr_saved_flags = 0; + + if (unlikely(lsr & UART_LSR_BRK_ERROR_BITS)) { + if (lsr & UART_LSR_BI) { + lsr &= ~(UART_LSR_FE | UART_LSR_PE); + port->icount.brk++; + /* + * We do the SysRQ and SAK checking + * here because otherwise the break + * may get masked by ignore_status_mask + * or read_status_mask. + */ + if (uart_handle_break(port)) + return; + } else if (lsr & UART_LSR_PE) + port->icount.parity++; + else if (lsr & UART_LSR_FE) + port->icount.frame++; + if (lsr & UART_LSR_OE) + port->icount.overrun++; + + /* + * Mask off conditions which should be ignored. + */ + lsr &= port->read_status_mask; + + if (lsr & UART_LSR_BI) { + DEBUG_INTR("handling break...."); + flag = TTY_BREAK; + } else if (lsr & UART_LSR_PE) + flag = TTY_PARITY; + else if (lsr & UART_LSR_FE) + flag = TTY_FRAME; + } + if (uart_handle_sysrq_char(port, ch)) + return; + + uart_insert_char(port, lsr, UART_LSR_OE, ch, flag); +} + /* * serial8250_rx_chars: processes according to the passed in LSR * value, and returns the remaining LSR bits not handled @@ -1421,67 +1482,10 @@ unsigned char serial8250_rx_chars(struct uart_8250_port *up, unsigned char lsr) { struct uart_port *port = &up->port; - unsigned char ch; int max_count = 256; - char flag; do { - if (likely(lsr & UART_LSR_DR)) - ch = serial_in(up, UART_RX); - else - /* - * Intel 82571 has a Serial Over Lan device that will - * set UART_LSR_BI without setting UART_LSR_DR when - * it receives a break. To avoid reading from the - * receive buffer without UART_LSR_DR bit set, we - * just force the read character to be 0 - */ - ch = 0; - - flag = TTY_NORMAL; - port->icount.rx++; - - lsr |= up->lsr_saved_flags; - up->lsr_saved_flags = 0; - - if (unlikely(lsr & UART_LSR_BRK_ERROR_BITS)) { - if (lsr & UART_LSR_BI) { - lsr &= ~(UART_LSR_FE | UART_LSR_PE); - port->icount.brk++; - /* - * We do the SysRQ and SAK checking - * here because otherwise the break - * may get masked by ignore_status_mask - * or read_status_mask. - */ - if (uart_handle_break(port)) - goto ignore_char; - } else if (lsr & UART_LSR_PE) - port->icount.parity++; - else if (lsr & UART_LSR_FE) - port->icount.frame++; - if (lsr & UART_LSR_OE) - port->icount.overrun++; - - /* - * Mask off conditions which should be ignored. - */ - lsr &= port->read_status_mask; - - if (lsr & UART_LSR_BI) { - DEBUG_INTR("handling break...."); - flag = TTY_BREAK; - } else if (lsr & UART_LSR_PE) - flag = TTY_PARITY; - else if (lsr & UART_LSR_FE) - flag = TTY_FRAME; - } - if (uart_handle_sysrq_char(port, ch)) - goto ignore_char; - - uart_insert_char(port, lsr, UART_LSR_OE, ch, flag); - -ignore_char: + serial8250_read_char(up, lsr); lsr = serial_in(up, UART_LSR); } while ((lsr & (UART_LSR_DR | UART_LSR_BI)) && (--max_count > 0)); spin_unlock(&port->lock); -- 2.20.1