From 72256cbd13904d4b4dbb16f5ec83a3293bb292c5 Mon Sep 17 00:00:00 2001 From: Felipe Balbi Date: Thu, 6 Sep 2012 15:45:24 +0300 Subject: [PATCH] serial: omap: refactor receive_chars() into rdi/rlsi handlers receive_chars() was getting too big and too difficult to follow. By splitting it into separate RDI and RSLI handlers, we have smaller functions which are easy to understand and only touch the pieces which they need to touch. Tested-by: Shubhrajyoti D Acked-by: Santosh Shilimkar Signed-off-by: Felipe Balbi Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/omap-serial.c | 205 +++++++++++++++---------------- 1 file changed, 101 insertions(+), 104 deletions(-) diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c index d5a08cb5213d..9c0a4ae97e65 100644 --- a/drivers/tty/serial/omap-serial.c +++ b/drivers/tty/serial/omap-serial.c @@ -196,74 +196,6 @@ static void serial_omap_stop_rx(struct uart_port *port) pm_runtime_put_autosuspend(up->dev); } -static inline void receive_chars(struct uart_omap_port *up, - unsigned int *status) -{ - struct tty_struct *tty = up->port.state->port.tty; - unsigned int flag, lsr = *status; - unsigned char ch = 0; - int max_count = 256; - - do { - if (likely(lsr & UART_LSR_DR)) - ch = serial_in(up, UART_RX); - flag = TTY_NORMAL; - up->port.icount.rx++; - - if (unlikely(lsr & UART_LSR_BRK_ERROR_BITS)) { - /* - * For statistics only - */ - if (lsr & UART_LSR_BI) { - lsr &= ~(UART_LSR_FE | UART_LSR_PE); - up->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(&up->port)) - goto ignore_char; - } else if (lsr & UART_LSR_PE) { - up->port.icount.parity++; - } else if (lsr & UART_LSR_FE) { - up->port.icount.frame++; - } - - if (lsr & UART_LSR_OE) - up->port.icount.overrun++; - - /* - * Mask off conditions which should be ignored. - */ - lsr &= up->port.read_status_mask; - -#ifdef CONFIG_SERIAL_OMAP_CONSOLE - if (up->port.line == up->port.cons->index) { - /* Recover the break flag from console xmit */ - lsr |= up->lsr_break_flag; - } -#endif - if (lsr & UART_LSR_BI) - 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(&up->port, ch)) - goto ignore_char; - uart_insert_char(&up->port, lsr, UART_LSR_OE, ch, flag); -ignore_char: - lsr = serial_in(up, UART_LSR); - } while ((lsr & (UART_LSR_DR | UART_LSR_BI)) && (max_count-- > 0)); - spin_unlock(&up->port.lock); - tty_flip_buffer_push(tty); - spin_lock(&up->port.lock); -} - static void transmit_chars(struct uart_omap_port *up) { struct circ_buf *xmit = &up->port.state->xmit; @@ -342,6 +274,68 @@ static unsigned int check_modem_status(struct uart_omap_port *up) return status; } +static void serial_omap_rlsi(struct uart_omap_port *up, unsigned int lsr) +{ + unsigned int flag; + + up->port.icount.rx++; + flag = TTY_NORMAL; + + if (lsr & UART_LSR_BI) { + flag = TTY_BREAK; + lsr &= ~(UART_LSR_FE | UART_LSR_PE); + up->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(&up->port)) + return; + + } + + if (lsr & UART_LSR_PE) { + flag = TTY_PARITY; + up->port.icount.parity++; + } + + if (lsr & UART_LSR_FE) { + flag = TTY_FRAME; + up->port.icount.frame++; + } + + if (lsr & UART_LSR_OE) + up->port.icount.overrun++; + +#ifdef CONFIG_SERIAL_OMAP_CONSOLE + if (up->port.line == up->port.cons->index) { + /* Recover the break flag from console xmit */ + lsr |= up->lsr_break_flag; + } +#endif + uart_insert_char(&up->port, lsr, UART_LSR_OE, 0, flag); +} + +static void serial_omap_rdi(struct uart_omap_port *up, unsigned int lsr) +{ + unsigned char ch = 0; + unsigned int flag; + + if (!(lsr & UART_LSR_DR)) + return; + + ch = serial_in(up, UART_RX); + flag = TTY_NORMAL; + up->port.icount.rx++; + + if (uart_handle_sysrq_char(&up->port, ch)) + return; + + uart_insert_char(&up->port, lsr, UART_LSR_OE, ch, flag); +} + /** * serial_omap_irq() - This handles the interrupt from one port * @irq: uart port irq number @@ -350,54 +344,57 @@ static unsigned int check_modem_status(struct uart_omap_port *up) static inline irqreturn_t serial_omap_irq(int irq, void *dev_id) { struct uart_omap_port *up = dev_id; + struct tty_struct *tty = up->port.state->port.tty; unsigned int iir, lsr; unsigned int type; unsigned long flags; irqreturn_t ret = IRQ_NONE; + int max_count = 256; spin_lock_irqsave(&up->port.lock, flags); pm_runtime_get_sync(up->dev); - iir = serial_in(up, UART_IIR); -again: - if (iir & UART_IIR_NO_INT) - goto out; - ret = IRQ_HANDLED; - lsr = serial_in(up, UART_LSR); + do { + iir = serial_in(up, UART_IIR); + if (iir & UART_IIR_NO_INT) + break; - /* extract IRQ type from IIR register */ - type = iir & 0x3e; + ret = IRQ_HANDLED; + lsr = serial_in(up, UART_LSR); - switch (type) { - case UART_IIR_MSI: - check_modem_status(up); - break; - case UART_IIR_THRI: - if (lsr & UART_LSR_THRE) - transmit_chars(up); - break; - case UART_IIR_RDI: - if (lsr & UART_LSR_DR) - receive_chars(up, &lsr); - break; - case UART_IIR_RLSI: - if (lsr & UART_LSR_BRK_ERROR_BITS) - receive_chars(up, &lsr); - break; - case UART_IIR_RX_TIMEOUT: - receive_chars(up, &lsr); - break; - case UART_IIR_CTS_RTS_DSR: - iir = serial_in(up, UART_IIR); - goto again; - case UART_IIR_XOFF: - /* FALLTHROUGH */ - default: - break; - } + /* extract IRQ type from IIR register */ + type = iir & 0x3e; + + switch (type) { + case UART_IIR_MSI: + check_modem_status(up); + break; + case UART_IIR_THRI: + if (lsr & UART_LSR_THRE) + transmit_chars(up); + break; + case UART_IIR_RX_TIMEOUT: + /* FALLTHROUGH */ + case UART_IIR_RDI: + serial_omap_rdi(up, lsr); + break; + case UART_IIR_RLSI: + serial_omap_rlsi(up, lsr); + break; + case UART_IIR_CTS_RTS_DSR: + /* simply try again */ + break; + case UART_IIR_XOFF: + /* FALLTHROUGH */ + default: + break; + } + } while (!(iir & UART_IIR_NO_INT) && max_count--); -out: spin_unlock_irqrestore(&up->port.lock, flags); + + tty_flip_buffer_push(tty); + pm_runtime_mark_last_busy(up->dev); pm_runtime_put_autosuspend(up->dev); up->port_activity = jiffies; -- 2.39.5