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![Jörn Engel](/assets/img/avatar_default.png)
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
832 lines
20 KiB
C
832 lines
20 KiB
C
/*
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* linux/drivers/char/amba.c
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*
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* Driver for AMBA serial ports
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*
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* Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
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*
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* Copyright 1999 ARM Limited
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* Copyright (C) 2000 Deep Blue Solutions Ltd.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*
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* $Id: amba.c,v 1.41 2002/07/28 10:03:27 rmk Exp $
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*
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* This is a generic driver for ARM AMBA-type serial ports. They
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* have a lot of 16550-like features, but are not register compatible.
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* Note that although they do have CTS, DCD and DSR inputs, they do
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* not have an RI input, nor do they have DTR or RTS outputs. If
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* required, these have to be supplied via some other means (eg, GPIO)
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* and hooked into this driver.
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*/
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#if defined(CONFIG_SERIAL_AMBA_PL011_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
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#define SUPPORT_SYSRQ
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#endif
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#include <linux/module.h>
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#include <linux/ioport.h>
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#include <linux/init.h>
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#include <linux/console.h>
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#include <linux/sysrq.h>
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#include <linux/device.h>
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#include <linux/tty.h>
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#include <linux/tty_flip.h>
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#include <linux/serial_core.h>
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#include <linux/serial.h>
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#include <linux/amba/bus.h>
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#include <linux/amba/serial.h>
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#include <linux/clk.h>
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#include <asm/io.h>
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#include <asm/sizes.h>
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#define UART_NR 14
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#define SERIAL_AMBA_MAJOR 204
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#define SERIAL_AMBA_MINOR 64
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#define SERIAL_AMBA_NR UART_NR
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#define AMBA_ISR_PASS_LIMIT 256
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#define UART_DR_ERROR (UART011_DR_OE|UART011_DR_BE|UART011_DR_PE|UART011_DR_FE)
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#define UART_DUMMY_DR_RX (1 << 16)
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/*
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* We wrap our port structure around the generic uart_port.
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*/
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struct uart_amba_port {
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struct uart_port port;
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struct clk *clk;
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unsigned int im; /* interrupt mask */
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unsigned int old_status;
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};
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static void pl011_stop_tx(struct uart_port *port)
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{
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struct uart_amba_port *uap = (struct uart_amba_port *)port;
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uap->im &= ~UART011_TXIM;
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writew(uap->im, uap->port.membase + UART011_IMSC);
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}
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static void pl011_start_tx(struct uart_port *port)
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{
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struct uart_amba_port *uap = (struct uart_amba_port *)port;
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uap->im |= UART011_TXIM;
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writew(uap->im, uap->port.membase + UART011_IMSC);
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}
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static void pl011_stop_rx(struct uart_port *port)
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{
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struct uart_amba_port *uap = (struct uart_amba_port *)port;
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uap->im &= ~(UART011_RXIM|UART011_RTIM|UART011_FEIM|
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UART011_PEIM|UART011_BEIM|UART011_OEIM);
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writew(uap->im, uap->port.membase + UART011_IMSC);
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}
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static void pl011_enable_ms(struct uart_port *port)
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{
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struct uart_amba_port *uap = (struct uart_amba_port *)port;
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uap->im |= UART011_RIMIM|UART011_CTSMIM|UART011_DCDMIM|UART011_DSRMIM;
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writew(uap->im, uap->port.membase + UART011_IMSC);
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}
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static void
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#ifdef SUPPORT_SYSRQ
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pl011_rx_chars(struct uart_amba_port *uap, struct pt_regs *regs)
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#else
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pl011_rx_chars(struct uart_amba_port *uap)
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#endif
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{
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struct tty_struct *tty = uap->port.info->tty;
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unsigned int status, ch, flag, max_count = 256;
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status = readw(uap->port.membase + UART01x_FR);
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while ((status & UART01x_FR_RXFE) == 0 && max_count--) {
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ch = readw(uap->port.membase + UART01x_DR) | UART_DUMMY_DR_RX;
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flag = TTY_NORMAL;
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uap->port.icount.rx++;
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/*
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* Note that the error handling code is
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* out of the main execution path
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*/
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if (unlikely(ch & UART_DR_ERROR)) {
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if (ch & UART011_DR_BE) {
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ch &= ~(UART011_DR_FE | UART011_DR_PE);
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uap->port.icount.brk++;
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if (uart_handle_break(&uap->port))
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goto ignore_char;
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} else if (ch & UART011_DR_PE)
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uap->port.icount.parity++;
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else if (ch & UART011_DR_FE)
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uap->port.icount.frame++;
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if (ch & UART011_DR_OE)
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uap->port.icount.overrun++;
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ch &= uap->port.read_status_mask;
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if (ch & UART011_DR_BE)
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flag = TTY_BREAK;
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else if (ch & UART011_DR_PE)
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flag = TTY_PARITY;
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else if (ch & UART011_DR_FE)
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flag = TTY_FRAME;
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}
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if (uart_handle_sysrq_char(&uap->port, ch & 255, regs))
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goto ignore_char;
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uart_insert_char(&uap->port, ch, UART011_DR_OE, ch, flag);
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ignore_char:
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status = readw(uap->port.membase + UART01x_FR);
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}
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tty_flip_buffer_push(tty);
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return;
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}
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static void pl011_tx_chars(struct uart_amba_port *uap)
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{
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struct circ_buf *xmit = &uap->port.info->xmit;
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int count;
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if (uap->port.x_char) {
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writew(uap->port.x_char, uap->port.membase + UART01x_DR);
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uap->port.icount.tx++;
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uap->port.x_char = 0;
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return;
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}
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if (uart_circ_empty(xmit) || uart_tx_stopped(&uap->port)) {
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pl011_stop_tx(&uap->port);
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return;
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}
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count = uap->port.fifosize >> 1;
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do {
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writew(xmit->buf[xmit->tail], uap->port.membase + UART01x_DR);
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xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
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uap->port.icount.tx++;
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if (uart_circ_empty(xmit))
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break;
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} while (--count > 0);
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if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
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uart_write_wakeup(&uap->port);
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if (uart_circ_empty(xmit))
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pl011_stop_tx(&uap->port);
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}
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static void pl011_modem_status(struct uart_amba_port *uap)
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{
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unsigned int status, delta;
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status = readw(uap->port.membase + UART01x_FR) & UART01x_FR_MODEM_ANY;
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delta = status ^ uap->old_status;
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uap->old_status = status;
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if (!delta)
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return;
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if (delta & UART01x_FR_DCD)
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uart_handle_dcd_change(&uap->port, status & UART01x_FR_DCD);
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if (delta & UART01x_FR_DSR)
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uap->port.icount.dsr++;
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if (delta & UART01x_FR_CTS)
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uart_handle_cts_change(&uap->port, status & UART01x_FR_CTS);
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wake_up_interruptible(&uap->port.info->delta_msr_wait);
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}
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static irqreturn_t pl011_int(int irq, void *dev_id, struct pt_regs *regs)
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{
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struct uart_amba_port *uap = dev_id;
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unsigned int status, pass_counter = AMBA_ISR_PASS_LIMIT;
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int handled = 0;
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spin_lock(&uap->port.lock);
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status = readw(uap->port.membase + UART011_MIS);
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if (status) {
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do {
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writew(status & ~(UART011_TXIS|UART011_RTIS|
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UART011_RXIS),
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uap->port.membase + UART011_ICR);
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if (status & (UART011_RTIS|UART011_RXIS))
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#ifdef SUPPORT_SYSRQ
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pl011_rx_chars(uap, regs);
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#else
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pl011_rx_chars(uap);
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#endif
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if (status & (UART011_DSRMIS|UART011_DCDMIS|
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UART011_CTSMIS|UART011_RIMIS))
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pl011_modem_status(uap);
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if (status & UART011_TXIS)
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pl011_tx_chars(uap);
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if (pass_counter-- == 0)
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break;
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status = readw(uap->port.membase + UART011_MIS);
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} while (status != 0);
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handled = 1;
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}
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spin_unlock(&uap->port.lock);
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return IRQ_RETVAL(handled);
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}
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static unsigned int pl01x_tx_empty(struct uart_port *port)
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{
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struct uart_amba_port *uap = (struct uart_amba_port *)port;
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unsigned int status = readw(uap->port.membase + UART01x_FR);
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return status & (UART01x_FR_BUSY|UART01x_FR_TXFF) ? 0 : TIOCSER_TEMT;
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}
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static unsigned int pl01x_get_mctrl(struct uart_port *port)
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{
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struct uart_amba_port *uap = (struct uart_amba_port *)port;
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unsigned int result = 0;
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unsigned int status = readw(uap->port.membase + UART01x_FR);
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#define BIT(uartbit, tiocmbit) \
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if (status & uartbit) \
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result |= tiocmbit
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BIT(UART01x_FR_DCD, TIOCM_CAR);
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BIT(UART01x_FR_DSR, TIOCM_DSR);
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BIT(UART01x_FR_CTS, TIOCM_CTS);
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BIT(UART011_FR_RI, TIOCM_RNG);
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#undef BIT
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return result;
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}
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static void pl011_set_mctrl(struct uart_port *port, unsigned int mctrl)
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{
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struct uart_amba_port *uap = (struct uart_amba_port *)port;
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unsigned int cr;
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cr = readw(uap->port.membase + UART011_CR);
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#define BIT(tiocmbit, uartbit) \
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if (mctrl & tiocmbit) \
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cr |= uartbit; \
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else \
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cr &= ~uartbit
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BIT(TIOCM_RTS, UART011_CR_RTS);
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BIT(TIOCM_DTR, UART011_CR_DTR);
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BIT(TIOCM_OUT1, UART011_CR_OUT1);
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BIT(TIOCM_OUT2, UART011_CR_OUT2);
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BIT(TIOCM_LOOP, UART011_CR_LBE);
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#undef BIT
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writew(cr, uap->port.membase + UART011_CR);
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}
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static void pl011_break_ctl(struct uart_port *port, int break_state)
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{
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struct uart_amba_port *uap = (struct uart_amba_port *)port;
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unsigned long flags;
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unsigned int lcr_h;
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spin_lock_irqsave(&uap->port.lock, flags);
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lcr_h = readw(uap->port.membase + UART011_LCRH);
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if (break_state == -1)
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lcr_h |= UART01x_LCRH_BRK;
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else
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lcr_h &= ~UART01x_LCRH_BRK;
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writew(lcr_h, uap->port.membase + UART011_LCRH);
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spin_unlock_irqrestore(&uap->port.lock, flags);
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}
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static int pl011_startup(struct uart_port *port)
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{
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struct uart_amba_port *uap = (struct uart_amba_port *)port;
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unsigned int cr;
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int retval;
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/*
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* Try to enable the clock producer.
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*/
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retval = clk_enable(uap->clk);
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if (retval)
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goto out;
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uap->port.uartclk = clk_get_rate(uap->clk);
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/*
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* Allocate the IRQ
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*/
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retval = request_irq(uap->port.irq, pl011_int, 0, "uart-pl011", uap);
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if (retval)
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goto clk_dis;
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writew(UART011_IFLS_RX4_8|UART011_IFLS_TX4_8,
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uap->port.membase + UART011_IFLS);
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/*
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* Provoke TX FIFO interrupt into asserting.
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*/
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cr = UART01x_CR_UARTEN | UART011_CR_TXE | UART011_CR_LBE;
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writew(cr, uap->port.membase + UART011_CR);
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writew(0, uap->port.membase + UART011_FBRD);
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writew(1, uap->port.membase + UART011_IBRD);
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writew(0, uap->port.membase + UART011_LCRH);
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writew(0, uap->port.membase + UART01x_DR);
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while (readw(uap->port.membase + UART01x_FR) & UART01x_FR_BUSY)
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barrier();
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cr = UART01x_CR_UARTEN | UART011_CR_RXE | UART011_CR_TXE;
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writew(cr, uap->port.membase + UART011_CR);
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/*
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* initialise the old status of the modem signals
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*/
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uap->old_status = readw(uap->port.membase + UART01x_FR) & UART01x_FR_MODEM_ANY;
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/*
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* Finally, enable interrupts
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*/
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spin_lock_irq(&uap->port.lock);
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uap->im = UART011_RXIM | UART011_RTIM;
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writew(uap->im, uap->port.membase + UART011_IMSC);
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spin_unlock_irq(&uap->port.lock);
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return 0;
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clk_dis:
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clk_disable(uap->clk);
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out:
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return retval;
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}
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static void pl011_shutdown(struct uart_port *port)
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{
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struct uart_amba_port *uap = (struct uart_amba_port *)port;
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unsigned long val;
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/*
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* disable all interrupts
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*/
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spin_lock_irq(&uap->port.lock);
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uap->im = 0;
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writew(uap->im, uap->port.membase + UART011_IMSC);
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writew(0xffff, uap->port.membase + UART011_ICR);
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spin_unlock_irq(&uap->port.lock);
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/*
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* Free the interrupt
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*/
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free_irq(uap->port.irq, uap);
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/*
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* disable the port
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*/
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writew(UART01x_CR_UARTEN | UART011_CR_TXE, uap->port.membase + UART011_CR);
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/*
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* disable break condition and fifos
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*/
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val = readw(uap->port.membase + UART011_LCRH);
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val &= ~(UART01x_LCRH_BRK | UART01x_LCRH_FEN);
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writew(val, uap->port.membase + UART011_LCRH);
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/*
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* Shut down the clock producer
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*/
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clk_disable(uap->clk);
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}
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static void
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pl011_set_termios(struct uart_port *port, struct termios *termios,
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struct termios *old)
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{
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unsigned int lcr_h, old_cr;
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unsigned long flags;
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unsigned int baud, quot;
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/*
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* Ask the core to calculate the divisor for us.
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*/
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baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
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quot = port->uartclk * 4 / baud;
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switch (termios->c_cflag & CSIZE) {
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case CS5:
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lcr_h = UART01x_LCRH_WLEN_5;
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break;
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case CS6:
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lcr_h = UART01x_LCRH_WLEN_6;
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break;
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case CS7:
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lcr_h = UART01x_LCRH_WLEN_7;
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break;
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default: // CS8
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lcr_h = UART01x_LCRH_WLEN_8;
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break;
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}
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if (termios->c_cflag & CSTOPB)
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lcr_h |= UART01x_LCRH_STP2;
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if (termios->c_cflag & PARENB) {
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lcr_h |= UART01x_LCRH_PEN;
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if (!(termios->c_cflag & PARODD))
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lcr_h |= UART01x_LCRH_EPS;
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}
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if (port->fifosize > 1)
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lcr_h |= UART01x_LCRH_FEN;
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spin_lock_irqsave(&port->lock, flags);
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/*
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* Update the per-port timeout.
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*/
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uart_update_timeout(port, termios->c_cflag, baud);
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port->read_status_mask = UART011_DR_OE | 255;
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if (termios->c_iflag & INPCK)
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port->read_status_mask |= UART011_DR_FE | UART011_DR_PE;
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if (termios->c_iflag & (BRKINT | PARMRK))
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port->read_status_mask |= UART011_DR_BE;
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/*
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* Characters to ignore
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*/
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port->ignore_status_mask = 0;
|
|
if (termios->c_iflag & IGNPAR)
|
|
port->ignore_status_mask |= UART011_DR_FE | UART011_DR_PE;
|
|
if (termios->c_iflag & IGNBRK) {
|
|
port->ignore_status_mask |= UART011_DR_BE;
|
|
/*
|
|
* If we're ignoring parity and break indicators,
|
|
* ignore overruns too (for real raw support).
|
|
*/
|
|
if (termios->c_iflag & IGNPAR)
|
|
port->ignore_status_mask |= UART011_DR_OE;
|
|
}
|
|
|
|
/*
|
|
* Ignore all characters if CREAD is not set.
|
|
*/
|
|
if ((termios->c_cflag & CREAD) == 0)
|
|
port->ignore_status_mask |= UART_DUMMY_DR_RX;
|
|
|
|
if (UART_ENABLE_MS(port, termios->c_cflag))
|
|
pl011_enable_ms(port);
|
|
|
|
/* first, disable everything */
|
|
old_cr = readw(port->membase + UART011_CR);
|
|
writew(0, port->membase + UART011_CR);
|
|
|
|
/* Set baud rate */
|
|
writew(quot & 0x3f, port->membase + UART011_FBRD);
|
|
writew(quot >> 6, port->membase + UART011_IBRD);
|
|
|
|
/*
|
|
* ----------v----------v----------v----------v-----
|
|
* NOTE: MUST BE WRITTEN AFTER UARTLCR_M & UARTLCR_L
|
|
* ----------^----------^----------^----------^-----
|
|
*/
|
|
writew(lcr_h, port->membase + UART011_LCRH);
|
|
writew(old_cr, port->membase + UART011_CR);
|
|
|
|
spin_unlock_irqrestore(&port->lock, flags);
|
|
}
|
|
|
|
static const char *pl011_type(struct uart_port *port)
|
|
{
|
|
return port->type == PORT_AMBA ? "AMBA/PL011" : NULL;
|
|
}
|
|
|
|
/*
|
|
* Release the memory region(s) being used by 'port'
|
|
*/
|
|
static void pl010_release_port(struct uart_port *port)
|
|
{
|
|
release_mem_region(port->mapbase, SZ_4K);
|
|
}
|
|
|
|
/*
|
|
* Request the memory region(s) being used by 'port'
|
|
*/
|
|
static int pl010_request_port(struct uart_port *port)
|
|
{
|
|
return request_mem_region(port->mapbase, SZ_4K, "uart-pl011")
|
|
!= NULL ? 0 : -EBUSY;
|
|
}
|
|
|
|
/*
|
|
* Configure/autoconfigure the port.
|
|
*/
|
|
static void pl010_config_port(struct uart_port *port, int flags)
|
|
{
|
|
if (flags & UART_CONFIG_TYPE) {
|
|
port->type = PORT_AMBA;
|
|
pl010_request_port(port);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* verify the new serial_struct (for TIOCSSERIAL).
|
|
*/
|
|
static int pl010_verify_port(struct uart_port *port, struct serial_struct *ser)
|
|
{
|
|
int ret = 0;
|
|
if (ser->type != PORT_UNKNOWN && ser->type != PORT_AMBA)
|
|
ret = -EINVAL;
|
|
if (ser->irq < 0 || ser->irq >= NR_IRQS)
|
|
ret = -EINVAL;
|
|
if (ser->baud_base < 9600)
|
|
ret = -EINVAL;
|
|
return ret;
|
|
}
|
|
|
|
static struct uart_ops amba_pl011_pops = {
|
|
.tx_empty = pl01x_tx_empty,
|
|
.set_mctrl = pl011_set_mctrl,
|
|
.get_mctrl = pl01x_get_mctrl,
|
|
.stop_tx = pl011_stop_tx,
|
|
.start_tx = pl011_start_tx,
|
|
.stop_rx = pl011_stop_rx,
|
|
.enable_ms = pl011_enable_ms,
|
|
.break_ctl = pl011_break_ctl,
|
|
.startup = pl011_startup,
|
|
.shutdown = pl011_shutdown,
|
|
.set_termios = pl011_set_termios,
|
|
.type = pl011_type,
|
|
.release_port = pl010_release_port,
|
|
.request_port = pl010_request_port,
|
|
.config_port = pl010_config_port,
|
|
.verify_port = pl010_verify_port,
|
|
};
|
|
|
|
static struct uart_amba_port *amba_ports[UART_NR];
|
|
|
|
#ifdef CONFIG_SERIAL_AMBA_PL011_CONSOLE
|
|
|
|
static void pl011_console_putchar(struct uart_port *port, int ch)
|
|
{
|
|
struct uart_amba_port *uap = (struct uart_amba_port *)port;
|
|
|
|
while (readw(uap->port.membase + UART01x_FR) & UART01x_FR_TXFF)
|
|
barrier();
|
|
writew(ch, uap->port.membase + UART01x_DR);
|
|
}
|
|
|
|
static void
|
|
pl011_console_write(struct console *co, const char *s, unsigned int count)
|
|
{
|
|
struct uart_amba_port *uap = amba_ports[co->index];
|
|
unsigned int status, old_cr, new_cr;
|
|
|
|
clk_enable(uap->clk);
|
|
|
|
/*
|
|
* First save the CR then disable the interrupts
|
|
*/
|
|
old_cr = readw(uap->port.membase + UART011_CR);
|
|
new_cr = old_cr & ~UART011_CR_CTSEN;
|
|
new_cr |= UART01x_CR_UARTEN | UART011_CR_TXE;
|
|
writew(new_cr, uap->port.membase + UART011_CR);
|
|
|
|
uart_console_write(&uap->port, s, count, pl011_console_putchar);
|
|
|
|
/*
|
|
* Finally, wait for transmitter to become empty
|
|
* and restore the TCR
|
|
*/
|
|
do {
|
|
status = readw(uap->port.membase + UART01x_FR);
|
|
} while (status & UART01x_FR_BUSY);
|
|
writew(old_cr, uap->port.membase + UART011_CR);
|
|
|
|
clk_disable(uap->clk);
|
|
}
|
|
|
|
static void __init
|
|
pl011_console_get_options(struct uart_amba_port *uap, int *baud,
|
|
int *parity, int *bits)
|
|
{
|
|
if (readw(uap->port.membase + UART011_CR) & UART01x_CR_UARTEN) {
|
|
unsigned int lcr_h, ibrd, fbrd;
|
|
|
|
lcr_h = readw(uap->port.membase + UART011_LCRH);
|
|
|
|
*parity = 'n';
|
|
if (lcr_h & UART01x_LCRH_PEN) {
|
|
if (lcr_h & UART01x_LCRH_EPS)
|
|
*parity = 'e';
|
|
else
|
|
*parity = 'o';
|
|
}
|
|
|
|
if ((lcr_h & 0x60) == UART01x_LCRH_WLEN_7)
|
|
*bits = 7;
|
|
else
|
|
*bits = 8;
|
|
|
|
ibrd = readw(uap->port.membase + UART011_IBRD);
|
|
fbrd = readw(uap->port.membase + UART011_FBRD);
|
|
|
|
*baud = uap->port.uartclk * 4 / (64 * ibrd + fbrd);
|
|
}
|
|
}
|
|
|
|
static int __init pl011_console_setup(struct console *co, char *options)
|
|
{
|
|
struct uart_amba_port *uap;
|
|
int baud = 38400;
|
|
int bits = 8;
|
|
int parity = 'n';
|
|
int flow = 'n';
|
|
|
|
/*
|
|
* Check whether an invalid uart number has been specified, and
|
|
* if so, search for the first available port that does have
|
|
* console support.
|
|
*/
|
|
if (co->index >= UART_NR)
|
|
co->index = 0;
|
|
uap = amba_ports[co->index];
|
|
|
|
uap->port.uartclk = clk_get_rate(uap->clk);
|
|
|
|
if (options)
|
|
uart_parse_options(options, &baud, &parity, &bits, &flow);
|
|
else
|
|
pl011_console_get_options(uap, &baud, &parity, &bits);
|
|
|
|
return uart_set_options(&uap->port, co, baud, parity, bits, flow);
|
|
}
|
|
|
|
static struct uart_driver amba_reg;
|
|
static struct console amba_console = {
|
|
.name = "ttyAMA",
|
|
.write = pl011_console_write,
|
|
.device = uart_console_device,
|
|
.setup = pl011_console_setup,
|
|
.flags = CON_PRINTBUFFER,
|
|
.index = -1,
|
|
.data = &amba_reg,
|
|
};
|
|
|
|
#define AMBA_CONSOLE (&amba_console)
|
|
#else
|
|
#define AMBA_CONSOLE NULL
|
|
#endif
|
|
|
|
static struct uart_driver amba_reg = {
|
|
.owner = THIS_MODULE,
|
|
.driver_name = "ttyAMA",
|
|
.dev_name = "ttyAMA",
|
|
.major = SERIAL_AMBA_MAJOR,
|
|
.minor = SERIAL_AMBA_MINOR,
|
|
.nr = UART_NR,
|
|
.cons = AMBA_CONSOLE,
|
|
};
|
|
|
|
static int pl011_probe(struct amba_device *dev, void *id)
|
|
{
|
|
struct uart_amba_port *uap;
|
|
void __iomem *base;
|
|
int i, ret;
|
|
|
|
for (i = 0; i < ARRAY_SIZE(amba_ports); i++)
|
|
if (amba_ports[i] == NULL)
|
|
break;
|
|
|
|
if (i == ARRAY_SIZE(amba_ports)) {
|
|
ret = -EBUSY;
|
|
goto out;
|
|
}
|
|
|
|
uap = kmalloc(sizeof(struct uart_amba_port), GFP_KERNEL);
|
|
if (uap == NULL) {
|
|
ret = -ENOMEM;
|
|
goto out;
|
|
}
|
|
|
|
base = ioremap(dev->res.start, PAGE_SIZE);
|
|
if (!base) {
|
|
ret = -ENOMEM;
|
|
goto free;
|
|
}
|
|
|
|
memset(uap, 0, sizeof(struct uart_amba_port));
|
|
uap->clk = clk_get(&dev->dev, "UARTCLK");
|
|
if (IS_ERR(uap->clk)) {
|
|
ret = PTR_ERR(uap->clk);
|
|
goto unmap;
|
|
}
|
|
|
|
uap->port.dev = &dev->dev;
|
|
uap->port.mapbase = dev->res.start;
|
|
uap->port.membase = base;
|
|
uap->port.iotype = UPIO_MEM;
|
|
uap->port.irq = dev->irq[0];
|
|
uap->port.fifosize = 16;
|
|
uap->port.ops = &amba_pl011_pops;
|
|
uap->port.flags = UPF_BOOT_AUTOCONF;
|
|
uap->port.line = i;
|
|
|
|
amba_ports[i] = uap;
|
|
|
|
amba_set_drvdata(dev, uap);
|
|
ret = uart_add_one_port(&amba_reg, &uap->port);
|
|
if (ret) {
|
|
amba_set_drvdata(dev, NULL);
|
|
amba_ports[i] = NULL;
|
|
clk_put(uap->clk);
|
|
unmap:
|
|
iounmap(base);
|
|
free:
|
|
kfree(uap);
|
|
}
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
static int pl011_remove(struct amba_device *dev)
|
|
{
|
|
struct uart_amba_port *uap = amba_get_drvdata(dev);
|
|
int i;
|
|
|
|
amba_set_drvdata(dev, NULL);
|
|
|
|
uart_remove_one_port(&amba_reg, &uap->port);
|
|
|
|
for (i = 0; i < ARRAY_SIZE(amba_ports); i++)
|
|
if (amba_ports[i] == uap)
|
|
amba_ports[i] = NULL;
|
|
|
|
iounmap(uap->port.membase);
|
|
clk_put(uap->clk);
|
|
kfree(uap);
|
|
return 0;
|
|
}
|
|
|
|
static struct amba_id pl011_ids[] __initdata = {
|
|
{
|
|
.id = 0x00041011,
|
|
.mask = 0x000fffff,
|
|
},
|
|
{ 0, 0 },
|
|
};
|
|
|
|
static struct amba_driver pl011_driver = {
|
|
.drv = {
|
|
.name = "uart-pl011",
|
|
},
|
|
.id_table = pl011_ids,
|
|
.probe = pl011_probe,
|
|
.remove = pl011_remove,
|
|
};
|
|
|
|
static int __init pl011_init(void)
|
|
{
|
|
int ret;
|
|
printk(KERN_INFO "Serial: AMBA PL011 UART driver\n");
|
|
|
|
ret = uart_register_driver(&amba_reg);
|
|
if (ret == 0) {
|
|
ret = amba_driver_register(&pl011_driver);
|
|
if (ret)
|
|
uart_unregister_driver(&amba_reg);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
static void __exit pl011_exit(void)
|
|
{
|
|
amba_driver_unregister(&pl011_driver);
|
|
uart_unregister_driver(&amba_reg);
|
|
}
|
|
|
|
module_init(pl011_init);
|
|
module_exit(pl011_exit);
|
|
|
|
MODULE_AUTHOR("ARM Ltd/Deep Blue Solutions Ltd");
|
|
MODULE_DESCRIPTION("ARM AMBA serial port driver");
|
|
MODULE_LICENSE("GPL");
|