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path: root/drivers/serial/clps711x.c
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Diffstat (limited to 'drivers/serial/clps711x.c')
-rw-r--r--drivers/serial/clps711x.c609
1 files changed, 609 insertions, 0 deletions
diff --git a/drivers/serial/clps711x.c b/drivers/serial/clps711x.c
new file mode 100644
index 00000000000..16592fae47f
--- /dev/null
+++ b/drivers/serial/clps711x.c
@@ -0,0 +1,609 @@
+/*
+ * linux/drivers/char/clps711x.c
+ *
+ * Driver for CLPS711x serial ports
+ *
+ * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
+ *
+ * Copyright 1999 ARM Limited
+ * Copyright (C) 2000 Deep Blue Solutions Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * $Id: clps711x.c,v 1.42 2002/07/28 10:03:28 rmk Exp $
+ *
+ */
+#include <linux/config.h>
+
+#if defined(CONFIG_SERIAL_CLPS711X_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
+#define SUPPORT_SYSRQ
+#endif
+
+#include <linux/module.h>
+#include <linux/ioport.h>
+#include <linux/init.h>
+#include <linux/console.h>
+#include <linux/sysrq.h>
+#include <linux/spinlock.h>
+#include <linux/device.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/serial_core.h>
+#include <linux/serial.h>
+
+#include <asm/hardware.h>
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <asm/hardware/clps7111.h>
+
+#define UART_NR 2
+
+#define SERIAL_CLPS711X_MAJOR 204
+#define SERIAL_CLPS711X_MINOR 40
+#define SERIAL_CLPS711X_NR UART_NR
+
+/*
+ * We use the relevant SYSCON register as a base address for these ports.
+ */
+#define UBRLCR(port) ((port)->iobase + UBRLCR1 - SYSCON1)
+#define UARTDR(port) ((port)->iobase + UARTDR1 - SYSCON1)
+#define SYSFLG(port) ((port)->iobase + SYSFLG1 - SYSCON1)
+#define SYSCON(port) ((port)->iobase + SYSCON1 - SYSCON1)
+
+#define TX_IRQ(port) ((port)->irq)
+#define RX_IRQ(port) ((port)->irq + 1)
+
+#define UART_ANY_ERR (UARTDR_FRMERR | UARTDR_PARERR | UARTDR_OVERR)
+
+#define tx_enabled(port) ((port)->unused[0])
+
+static void
+clps711xuart_stop_tx(struct uart_port *port, unsigned int tty_stop)
+{
+ if (tx_enabled(port)) {
+ disable_irq(TX_IRQ(port));
+ tx_enabled(port) = 0;
+ }
+}
+
+static void
+clps711xuart_start_tx(struct uart_port *port, unsigned int tty_start)
+{
+ if (!tx_enabled(port)) {
+ enable_irq(TX_IRQ(port));
+ tx_enabled(port) = 1;
+ }
+}
+
+static void clps711xuart_stop_rx(struct uart_port *port)
+{
+ disable_irq(RX_IRQ(port));
+}
+
+static void clps711xuart_enable_ms(struct uart_port *port)
+{
+}
+
+static irqreturn_t clps711xuart_int_rx(int irq, void *dev_id, struct pt_regs *regs)
+{
+ struct uart_port *port = dev_id;
+ struct tty_struct *tty = port->info->tty;
+ unsigned int status, ch, flg, ignored = 0;
+
+ status = clps_readl(SYSFLG(port));
+ while (!(status & SYSFLG_URXFE)) {
+ ch = clps_readl(UARTDR(port));
+
+ if (tty->flip.count >= TTY_FLIPBUF_SIZE)
+ goto ignore_char;
+ port->icount.rx++;
+
+ flg = TTY_NORMAL;
+
+ /*
+ * Note that the error handling code is
+ * out of the main execution path
+ */
+ if (ch & UART_ANY_ERR)
+ goto handle_error;
+
+ if (uart_handle_sysrq_char(port, ch, regs))
+ goto ignore_char;
+
+ error_return:
+ tty_insert_flip_char(tty, ch, flg);
+ ignore_char:
+ status = clps_readl(SYSFLG(port));
+ }
+ out:
+ tty_flip_buffer_push(tty);
+ return IRQ_HANDLED;
+
+ handle_error:
+ if (ch & UARTDR_PARERR)
+ port->icount.parity++;
+ else if (ch & UARTDR_FRMERR)
+ port->icount.frame++;
+ if (ch & UARTDR_OVERR)
+ port->icount.overrun++;
+
+ if (ch & port->ignore_status_mask) {
+ if (++ignored > 100)
+ goto out;
+ goto ignore_char;
+ }
+ ch &= port->read_status_mask;
+
+ if (ch & UARTDR_PARERR)
+ flg = TTY_PARITY;
+ else if (ch & UARTDR_FRMERR)
+ flg = TTY_FRAME;
+
+ if (ch & UARTDR_OVERR) {
+ /*
+ * CHECK: does overrun affect the current character?
+ * ASSUMPTION: it does not.
+ */
+ tty_insert_flip_char(tty, ch, flg);
+ ch = 0;
+ flg = TTY_OVERRUN;
+ }
+#ifdef SUPPORT_SYSRQ
+ port->sysrq = 0;
+#endif
+ goto error_return;
+}
+
+static irqreturn_t clps711xuart_int_tx(int irq, void *dev_id, struct pt_regs *regs)
+{
+ struct uart_port *port = dev_id;
+ struct circ_buf *xmit = &port->info->xmit;
+ int count;
+
+ if (port->x_char) {
+ clps_writel(port->x_char, UARTDR(port));
+ port->icount.tx++;
+ port->x_char = 0;
+ return IRQ_HANDLED;
+ }
+ if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
+ clps711xuart_stop_tx(port, 0);
+ return IRQ_HANDLED;
+ }
+
+ count = port->fifosize >> 1;
+ do {
+ clps_writel(xmit->buf[xmit->tail], UARTDR(port));
+ xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+ port->icount.tx++;
+ if (uart_circ_empty(xmit))
+ break;
+ } while (--count > 0);
+
+ if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+ uart_write_wakeup(port);
+
+ if (uart_circ_empty(xmit))
+ clps711xuart_stop_tx(port, 0);
+
+ return IRQ_HANDLED;
+}
+
+static unsigned int clps711xuart_tx_empty(struct uart_port *port)
+{
+ unsigned int status = clps_readl(SYSFLG(port));
+ return status & SYSFLG_UBUSY ? 0 : TIOCSER_TEMT;
+}
+
+static unsigned int clps711xuart_get_mctrl(struct uart_port *port)
+{
+ unsigned int port_addr;
+ unsigned int result = 0;
+ unsigned int status;
+
+ port_addr = SYSFLG(port);
+ if (port_addr == SYSFLG1) {
+ status = clps_readl(SYSFLG1);
+ if (status & SYSFLG1_DCD)
+ result |= TIOCM_CAR;
+ if (status & SYSFLG1_DSR)
+ result |= TIOCM_DSR;
+ if (status & SYSFLG1_CTS)
+ result |= TIOCM_CTS;
+ }
+
+ return result;
+}
+
+static void
+clps711xuart_set_mctrl_null(struct uart_port *port, unsigned int mctrl)
+{
+}
+
+static void clps711xuart_break_ctl(struct uart_port *port, int break_state)
+{
+ unsigned long flags;
+ unsigned int ubrlcr;
+
+ spin_lock_irqsave(&port->lock, flags);
+ ubrlcr = clps_readl(UBRLCR(port));
+ if (break_state == -1)
+ ubrlcr |= UBRLCR_BREAK;
+ else
+ ubrlcr &= ~UBRLCR_BREAK;
+ clps_writel(ubrlcr, UBRLCR(port));
+ spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static int clps711xuart_startup(struct uart_port *port)
+{
+ unsigned int syscon;
+ int retval;
+
+ tx_enabled(port) = 1;
+
+ /*
+ * Allocate the IRQs
+ */
+ retval = request_irq(TX_IRQ(port), clps711xuart_int_tx, 0,
+ "clps711xuart_tx", port);
+ if (retval)
+ return retval;
+
+ retval = request_irq(RX_IRQ(port), clps711xuart_int_rx, 0,
+ "clps711xuart_rx", port);
+ if (retval) {
+ free_irq(TX_IRQ(port), port);
+ return retval;
+ }
+
+ /*
+ * enable the port
+ */
+ syscon = clps_readl(SYSCON(port));
+ syscon |= SYSCON_UARTEN;
+ clps_writel(syscon, SYSCON(port));
+
+ return 0;
+}
+
+static void clps711xuart_shutdown(struct uart_port *port)
+{
+ unsigned int ubrlcr, syscon;
+
+ /*
+ * Free the interrupt
+ */
+ free_irq(TX_IRQ(port), port); /* TX interrupt */
+ free_irq(RX_IRQ(port), port); /* RX interrupt */
+
+ /*
+ * disable the port
+ */
+ syscon = clps_readl(SYSCON(port));
+ syscon &= ~SYSCON_UARTEN;
+ clps_writel(syscon, SYSCON(port));
+
+ /*
+ * disable break condition and fifos
+ */
+ ubrlcr = clps_readl(UBRLCR(port));
+ ubrlcr &= ~(UBRLCR_FIFOEN | UBRLCR_BREAK);
+ clps_writel(ubrlcr, UBRLCR(port));
+}
+
+static void
+clps711xuart_set_termios(struct uart_port *port, struct termios *termios,
+ struct termios *old)
+{
+ unsigned int ubrlcr, baud, quot;
+ unsigned long flags;
+
+ /*
+ * We don't implement CREAD.
+ */
+ termios->c_cflag |= CREAD;
+
+ /*
+ * Ask the core to calculate the divisor for us.
+ */
+ baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
+ quot = uart_get_divisor(port, baud);
+
+ switch (termios->c_cflag & CSIZE) {
+ case CS5:
+ ubrlcr = UBRLCR_WRDLEN5;
+ break;
+ case CS6:
+ ubrlcr = UBRLCR_WRDLEN6;
+ break;
+ case CS7:
+ ubrlcr = UBRLCR_WRDLEN7;
+ break;
+ default: // CS8
+ ubrlcr = UBRLCR_WRDLEN8;
+ break;
+ }
+ if (termios->c_cflag & CSTOPB)
+ ubrlcr |= UBRLCR_XSTOP;
+ if (termios->c_cflag & PARENB) {
+ ubrlcr |= UBRLCR_PRTEN;
+ if (!(termios->c_cflag & PARODD))
+ ubrlcr |= UBRLCR_EVENPRT;
+ }
+ if (port->fifosize > 1)
+ ubrlcr |= UBRLCR_FIFOEN;
+
+ spin_lock_irqsave(&port->lock, flags);
+
+ /*
+ * Update the per-port timeout.
+ */
+ uart_update_timeout(port, termios->c_cflag, baud);
+
+ port->read_status_mask = UARTDR_OVERR;
+ if (termios->c_iflag & INPCK)
+ port->read_status_mask |= UARTDR_PARERR | UARTDR_FRMERR;
+
+ /*
+ * Characters to ignore
+ */
+ port->ignore_status_mask = 0;
+ if (termios->c_iflag & IGNPAR)
+ port->ignore_status_mask |= UARTDR_FRMERR | UARTDR_PARERR;
+ if (termios->c_iflag & IGNBRK) {
+ /*
+ * If we're ignoring parity and break indicators,
+ * ignore overruns to (for real raw support).
+ */
+ if (termios->c_iflag & IGNPAR)
+ port->ignore_status_mask |= UARTDR_OVERR;
+ }
+
+ quot -= 1;
+
+ clps_writel(ubrlcr | quot, UBRLCR(port));
+
+ spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static const char *clps711xuart_type(struct uart_port *port)
+{
+ return port->type == PORT_CLPS711X ? "CLPS711x" : NULL;
+}
+
+/*
+ * Configure/autoconfigure the port.
+ */
+static void clps711xuart_config_port(struct uart_port *port, int flags)
+{
+ if (flags & UART_CONFIG_TYPE)
+ port->type = PORT_CLPS711X;
+}
+
+static void clps711xuart_release_port(struct uart_port *port)
+{
+}
+
+static int clps711xuart_request_port(struct uart_port *port)
+{
+ return 0;
+}
+
+static struct uart_ops clps711x_pops = {
+ .tx_empty = clps711xuart_tx_empty,
+ .set_mctrl = clps711xuart_set_mctrl_null,
+ .get_mctrl = clps711xuart_get_mctrl,
+ .stop_tx = clps711xuart_stop_tx,
+ .start_tx = clps711xuart_start_tx,
+ .stop_rx = clps711xuart_stop_rx,
+ .enable_ms = clps711xuart_enable_ms,
+ .break_ctl = clps711xuart_break_ctl,
+ .startup = clps711xuart_startup,
+ .shutdown = clps711xuart_shutdown,
+ .set_termios = clps711xuart_set_termios,
+ .type = clps711xuart_type,
+ .config_port = clps711xuart_config_port,
+ .release_port = clps711xuart_release_port,
+ .request_port = clps711xuart_request_port,
+};
+
+static struct uart_port clps711x_ports[UART_NR] = {
+ {
+ .iobase = SYSCON1,
+ .irq = IRQ_UTXINT1, /* IRQ_URXINT1, IRQ_UMSINT */
+ .uartclk = 3686400,
+ .fifosize = 16,
+ .ops = &clps711x_pops,
+ .line = 0,
+ .flags = ASYNC_BOOT_AUTOCONF,
+ },
+ {
+ .iobase = SYSCON2,
+ .irq = IRQ_UTXINT2, /* IRQ_URXINT2 */
+ .uartclk = 3686400,
+ .fifosize = 16,
+ .ops = &clps711x_pops,
+ .line = 1,
+ .flags = ASYNC_BOOT_AUTOCONF,
+ }
+};
+
+#ifdef CONFIG_SERIAL_CLPS711X_CONSOLE
+/*
+ * Print a string to the serial port trying not to disturb
+ * any possible real use of the port...
+ *
+ * The console_lock must be held when we get here.
+ *
+ * Note that this is called with interrupts already disabled
+ */
+static void
+clps711xuart_console_write(struct console *co, const char *s,
+ unsigned int count)
+{
+ struct uart_port *port = clps711x_ports + co->index;
+ unsigned int status, syscon;
+ int i;
+
+ /*
+ * Ensure that the port is enabled.
+ */
+ syscon = clps_readl(SYSCON(port));
+ clps_writel(syscon | SYSCON_UARTEN, SYSCON(port));
+
+ /*
+ * Now, do each character
+ */
+ for (i = 0; i < count; i++) {
+ do {
+ status = clps_readl(SYSFLG(port));
+ } while (status & SYSFLG_UTXFF);
+ clps_writel(s[i], UARTDR(port));
+ if (s[i] == '\n') {
+ do {
+ status = clps_readl(SYSFLG(port));
+ } while (status & SYSFLG_UTXFF);
+ clps_writel('\r', UARTDR(port));
+ }
+ }
+
+ /*
+ * Finally, wait for transmitter to become empty
+ * and restore the uart state.
+ */
+ do {
+ status = clps_readl(SYSFLG(port));
+ } while (status & SYSFLG_UBUSY);
+
+ clps_writel(syscon, SYSCON(port));
+}
+
+static void __init
+clps711xuart_console_get_options(struct uart_port *port, int *baud,
+ int *parity, int *bits)
+{
+ if (clps_readl(SYSCON(port)) & SYSCON_UARTEN) {
+ unsigned int ubrlcr, quot;
+
+ ubrlcr = clps_readl(UBRLCR(port));
+
+ *parity = 'n';
+ if (ubrlcr & UBRLCR_PRTEN) {
+ if (ubrlcr & UBRLCR_EVENPRT)
+ *parity = 'e';
+ else
+ *parity = 'o';
+ }
+
+ if ((ubrlcr & UBRLCR_WRDLEN_MASK) == UBRLCR_WRDLEN7)
+ *bits = 7;
+ else
+ *bits = 8;
+
+ quot = ubrlcr & UBRLCR_BAUD_MASK;
+ *baud = port->uartclk / (16 * (quot + 1));
+ }
+}
+
+static int __init clps711xuart_console_setup(struct console *co, char *options)
+{
+ struct uart_port *port;
+ 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.
+ */
+ port = uart_get_console(clps711x_ports, UART_NR, co);
+
+ if (options)
+ uart_parse_options(options, &baud, &parity, &bits, &flow);
+ else
+ clps711xuart_console_get_options(port, &baud, &parity, &bits);
+
+ return uart_set_options(port, co, baud, parity, bits, flow);
+}
+
+extern struct uart_driver clps711x_reg;
+static struct console clps711x_console = {
+ .name = "ttyCL",
+ .write = clps711xuart_console_write,
+ .device = uart_console_device,
+ .setup = clps711xuart_console_setup,
+ .flags = CON_PRINTBUFFER,
+ .index = -1,
+ .data = &clps711x_reg,
+};
+
+static int __init clps711xuart_console_init(void)
+{
+ register_console(&clps711x_console);
+ return 0;
+}
+console_initcall(clps711xuart_console_init);
+
+#define CLPS711X_CONSOLE &clps711x_console
+#else
+#define CLPS711X_CONSOLE NULL
+#endif
+
+static struct uart_driver clps711x_reg = {
+ .driver_name = "ttyCL",
+ .dev_name = "ttyCL",
+ .major = SERIAL_CLPS711X_MAJOR,
+ .minor = SERIAL_CLPS711X_MINOR,
+ .nr = UART_NR,
+
+ .cons = CLPS711X_CONSOLE,
+};
+
+static int __init clps711xuart_init(void)
+{
+ int ret, i;
+
+ printk(KERN_INFO "Serial: CLPS711x driver $Revision: 1.42 $\n");
+
+ ret = uart_register_driver(&clps711x_reg);
+ if (ret)
+ return ret;
+
+ for (i = 0; i < UART_NR; i++)
+ uart_add_one_port(&clps711x_reg, &clps711x_ports[i]);
+
+ return 0;
+}
+
+static void __exit clps711xuart_exit(void)
+{
+ int i;
+
+ for (i = 0; i < UART_NR; i++)
+ uart_remove_one_port(&clps711x_reg, &clps711x_ports[i]);
+
+ uart_unregister_driver(&clps711x_reg);
+}
+
+module_init(clps711xuart_init);
+module_exit(clps711xuart_exit);
+
+MODULE_AUTHOR("Deep Blue Solutions Ltd");
+MODULE_DESCRIPTION("CLPS-711x generic serial driver $Revision: 1.42 $");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_CHARDEV(SERIAL_CLPS711X_MAJOR, SERIAL_CLPS711X_MINOR);