From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755775Ab2HUJWL (ORCPT ); Tue, 21 Aug 2012 05:22:11 -0400 Received: from na3sys009aog125.obsmtp.com ([74.125.149.153]:43583 "EHLO na3sys009aog125.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755398Ab2HUJUY (ORCPT ); Tue, 21 Aug 2012 05:20:24 -0400 From: Felipe Balbi To: alan@linux.intel.com Cc: Tony Lindgren , Kevin Hilman , Linux OMAP Mailing List , Linux ARM Kernel Mailing List , linux-serial@vger.kernel.org, Linux Kernel Mailing List , Santosh Shilimkar , Shubhrajyoti Datta , Felipe Balbi Subject: [RFC/PATCH 08/13] serial: omap: refactor receive_chars() into rdi/rlsi handlers Date: Tue, 21 Aug 2012 12:15:50 +0300 Message-Id: <1345540555-24359-9-git-send-email-balbi@ti.com> X-Mailer: git-send-email 1.7.12.rc3 In-Reply-To: <1345540555-24359-1-git-send-email-balbi@ti.com> References: <1345540555-24359-1-git-send-email-balbi@ti.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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. Signed-off-by: Felipe Balbi --- drivers/tty/serial/omap-serial.c | 203 +++++++++++++++++++-------------------- 1 file changed, 100 insertions(+), 103 deletions(-) diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c index 1ca08b8..74a4f0a 100644 --- a/drivers/tty/serial/omap-serial.c +++ b/drivers/tty/serial/omap-serial.c @@ -195,74 +195,6 @@ 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; @@ -341,6 +273,68 @@ 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 @@ -349,52 +343,55 @@ 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; + 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; - 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; + 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; -- 1.7.12.rc3