Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 549 insertions, 0 deletions

diff --git a/drivers/serial/v850e_uart.c b/drivers/serial/v850e_uart.c
new file mode 100644
index 0000000..bb48278
--- /dev/null
+++ b/drivers/serial/v850e_uart.c
@@ -0,0 +1,549 @@
+/*
+ * drivers/serial/v850e_uart.c -- Serial I/O using V850E on-chip UART or UARTB
+ *
+ *  Copyright (C) 2001,02,03  NEC Electronics Corporation
+ *  Copyright (C) 2001,02,03  Miles Bader <miles@gnu.org>
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License.  See the file COPYING in the main directory of this
+ * archive for more details.
+ *
+ * Written by Miles Bader <miles@gnu.org>
+ */
+
+/* This driver supports both the original V850E UART interface (called
+   merely `UART' in the docs) and the newer `UARTB' interface, which is
+   roughly a superset of the first one.  The selection is made at
+   configure time -- if CONFIG_V850E_UARTB is defined, then UARTB is
+   presumed, otherwise the old UART -- as these are on-CPU UARTS, a system
+   can never have both.
+
+   The UARTB interface also has a 16-entry FIFO mode, which is not
+   yet supported by this driver.  */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/console.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/serial.h>
+#include <linux/serial_core.h>
+
+#include <asm/v850e_uart.h>
+
+/* Initial UART state.  This may be overridden by machine-dependent headers. */
+#ifndef V850E_UART_INIT_BAUD
+#define V850E_UART_INIT_BAUD	115200
+#endif
+#ifndef V850E_UART_INIT_CFLAGS
+#define V850E_UART_INIT_CFLAGS	(B115200 | CS8 | CREAD)
+#endif
+
+/* A string used for prefixing printed descriptions; since the same UART
+   macro is actually used on other chips than the V850E.  This must be a
+   constant string.  */
+#ifndef V850E_UART_CHIP_NAME
+#define V850E_UART_CHIP_NAME	"V850E"
+#endif
+
+#define V850E_UART_MINOR_BASE	64	   /* First tty minor number */
+
+
+/* Low-level UART functions.  */
+
+/* Configure and turn on uart channel CHAN, using the termios `control
+   modes' bits in CFLAGS, and a baud-rate of BAUD.  */
+void v850e_uart_configure (unsigned chan, unsigned cflags, unsigned baud)
+{
+	int flags;
+	v850e_uart_speed_t old_speed;
+	v850e_uart_config_t old_config;
+	v850e_uart_speed_t new_speed = v850e_uart_calc_speed (baud);
+	v850e_uart_config_t new_config = v850e_uart_calc_config (cflags);
+
+	/* Disable interrupts while we're twiddling the hardware.  */
+	local_irq_save (flags);
+
+#ifdef V850E_UART_PRE_CONFIGURE
+	V850E_UART_PRE_CONFIGURE (chan, cflags, baud);
+#endif
+
+	old_config = V850E_UART_CONFIG (chan);
+	old_speed = v850e_uart_speed (chan);
+
+	if (! v850e_uart_speed_eq (old_speed, new_speed)) {
+		/* The baud rate has changed.  First, disable the UART.  */
+		V850E_UART_CONFIG (chan) = V850E_UART_CONFIG_FINI;
+		old_config = 0;	/* Force the uart to be re-initialized. */
+
+		/* Reprogram the baud-rate generator.  */
+		v850e_uart_set_speed (chan, new_speed);
+	}
+
+	if (! (old_config & V850E_UART_CONFIG_ENABLED)) {
+		/* If we are using the uart for the first time, start by
+		   enabling it, which must be done before turning on any
+		   other bits.  */
+		V850E_UART_CONFIG (chan) = V850E_UART_CONFIG_INIT;
+		/* See the initial state.  */
+		old_config = V850E_UART_CONFIG (chan);
+	}
+
+	if (new_config != old_config) {
+		/* Which of the TXE/RXE bits we'll temporarily turn off
+		   before changing other control bits.  */
+		unsigned temp_disable = 0;
+		/* Which of the TXE/RXE bits will be enabled.  */
+		unsigned enable = 0;
+		unsigned changed_bits = new_config ^ old_config;
+
+		/* Which of RX/TX will be enabled in the new configuration.  */
+		if (new_config & V850E_UART_CONFIG_RX_BITS)
+			enable |= (new_config & V850E_UART_CONFIG_RX_ENABLE);
+		if (new_config & V850E_UART_CONFIG_TX_BITS)
+			enable |= (new_config & V850E_UART_CONFIG_TX_ENABLE);
+
+		/* Figure out which of RX/TX needs to be disabled; note
+		   that this will only happen if they're not already
+		   disabled.  */
+		if (changed_bits & V850E_UART_CONFIG_RX_BITS)
+			temp_disable
+				|= (old_config & V850E_UART_CONFIG_RX_ENABLE);
+		if (changed_bits & V850E_UART_CONFIG_TX_BITS)
+			temp_disable
+				|= (old_config & V850E_UART_CONFIG_TX_ENABLE);
+
+		/* We have to turn off RX and/or TX mode before changing
+		   any associated control bits.  */
+		if (temp_disable)
+			V850E_UART_CONFIG (chan) = old_config & ~temp_disable;
+
+		/* Write the new control bits, while RX/TX are disabled. */ 
+		if (changed_bits & ~enable)
+			V850E_UART_CONFIG (chan) = new_config & ~enable;
+
+		v850e_uart_config_delay (new_config, new_speed);
+
+		/* Write the final version, with enable bits turned on.  */
+		V850E_UART_CONFIG (chan) = new_config;
+	}
+
+	local_irq_restore (flags);
+}
+
+
+/*  Low-level console. */
+
+#ifdef CONFIG_V850E_UART_CONSOLE
+
+static void v850e_uart_cons_write (struct console *co,
+				   const char *s, unsigned count)
+{
+	if (count > 0) {
+		unsigned chan = co->index;
+		unsigned irq = V850E_UART_TX_IRQ (chan);
+		int irq_was_enabled, irq_was_pending, flags;
+
+		/* We don't want to get `transmission completed'
+		   interrupts, since we're busy-waiting, so we disable them
+		   while sending (we don't disable interrupts entirely
+		   because sending over a serial line is really slow).  We
+		   save the status of the tx interrupt and restore it when
+		   we're done so that using printk doesn't interfere with
+		   normal serial transmission (other than interleaving the
+		   output, of course!).  This should work correctly even if
+		   this function is interrupted and the interrupt printks
+		   something.  */
+
+		/* Disable interrupts while fiddling with tx interrupt.  */
+		local_irq_save (flags);
+		/* Get current tx interrupt status.  */
+		irq_was_enabled = v850e_intc_irq_enabled (irq);
+		irq_was_pending = v850e_intc_irq_pending (irq);
+		/* Disable tx interrupt if necessary.  */
+		if (irq_was_enabled)
+			v850e_intc_disable_irq (irq);
+		/* Turn interrupts back on.  */
+		local_irq_restore (flags);
+
+		/* Send characters.  */
+		while (count > 0) {
+			int ch = *s++;
+
+			if (ch == '\n') {
+				/* We don't have the benefit of a tty
+				   driver, so translate NL into CR LF.  */
+				v850e_uart_wait_for_xmit_ok (chan);
+				v850e_uart_putc (chan, '\r');
+			}
+
+			v850e_uart_wait_for_xmit_ok (chan);
+			v850e_uart_putc (chan, ch);
+
+			count--;
+		}
+
+		/* Restore saved tx interrupt status.  */
+		if (irq_was_enabled) {
+			/* Wait for the last character we sent to be
+			   completely transmitted (as we'll get an
+			   interrupt interrupt at that point).  */
+			v850e_uart_wait_for_xmit_done (chan);
+			/* Clear pending interrupts received due
+			   to our transmission, unless there was already
+			   one pending, in which case we want the
+			   handler to be called.  */
+			if (! irq_was_pending)
+				v850e_intc_clear_pending_irq (irq);
+			/* ... and then turn back on handling.  */
+			v850e_intc_enable_irq (irq);
+		}
+	}
+}
+
+extern struct uart_driver v850e_uart_driver;
+static struct console v850e_uart_cons =
+{
+    .name	= "ttyS",
+    .write	= v850e_uart_cons_write,
+    .device	= uart_console_device,
+    .flags	= CON_PRINTBUFFER,
+    .cflag	= V850E_UART_INIT_CFLAGS,
+    .index	= -1,
+    .data	= &v850e_uart_driver,
+};
+
+void v850e_uart_cons_init (unsigned chan)
+{
+	v850e_uart_configure (chan, V850E_UART_INIT_CFLAGS,
+			      V850E_UART_INIT_BAUD);
+	v850e_uart_cons.index = chan;
+	register_console (&v850e_uart_cons);
+	printk ("Console: %s on-chip UART channel %d\n",
+		V850E_UART_CHIP_NAME, chan);
+}
+
+/* This is what the init code actually calls.  */
+static int v850e_uart_console_init (void)
+{
+	v850e_uart_cons_init (V850E_UART_CONSOLE_CHANNEL);
+	return 0;
+}
+console_initcall(v850e_uart_console_init);
+
+#define V850E_UART_CONSOLE &v850e_uart_cons
+
+#else /* !CONFIG_V850E_UART_CONSOLE */
+#define V850E_UART_CONSOLE 0
+#endif /* CONFIG_V850E_UART_CONSOLE */
+
+/* TX/RX interrupt handlers.  */
+
+static void v850e_uart_stop_tx (struct uart_port *port, unsigned tty_stop);
+
+void v850e_uart_tx (struct uart_port *port)
+{
+	struct circ_buf *xmit = &port->info->xmit;
+	int stopped = uart_tx_stopped (port);
+
+	if (v850e_uart_xmit_ok (port->line)) {
+		int tx_ch;
+
+		if (port->x_char) {
+			tx_ch = port->x_char;
+			port->x_char = 0;
+		} else if (!uart_circ_empty (xmit) && !stopped) {
+			tx_ch = xmit->buf[xmit->tail];
+			xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+		} else
+			goto no_xmit;
+
+		v850e_uart_putc (port->line, tx_ch);
+		port->icount.tx++;
+
+		if (uart_circ_chars_pending (xmit) < WAKEUP_CHARS)
+			uart_write_wakeup (port);
+	}
+
+ no_xmit:
+	if (uart_circ_empty (xmit) || stopped)
+		v850e_uart_stop_tx (port, stopped);
+}
+
+static irqreturn_t v850e_uart_tx_irq(int irq, void *data, struct pt_regs *regs)
+{
+	struct uart_port *port = data;
+	v850e_uart_tx (port);
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t v850e_uart_rx_irq(int irq, void *data, struct pt_regs *regs)
+{
+	struct uart_port *port = data;
+	unsigned ch_stat = TTY_NORMAL;
+	unsigned ch = v850e_uart_getc (port->line);
+	unsigned err = v850e_uart_err (port->line);
+
+	if (err) {
+		if (err & V850E_UART_ERR_OVERRUN) {
+			ch_stat = TTY_OVERRUN;
+			port->icount.overrun++;
+		} else if (err & V850E_UART_ERR_FRAME) {
+			ch_stat = TTY_FRAME;
+			port->icount.frame++;
+		} else if (err & V850E_UART_ERR_PARITY) {
+			ch_stat = TTY_PARITY;
+			port->icount.parity++;
+		}
+	}
+
+	port->icount.rx++;
+
+	tty_insert_flip_char (port->info->tty, ch, ch_stat);
+	tty_schedule_flip (port->info->tty);
+
+	return IRQ_HANDLED;
+}
+
+
+/* Control functions for the serial framework.  */
+
+static void v850e_uart_nop (struct uart_port *port) { }
+static int v850e_uart_success (struct uart_port *port) { return 0; }
+
+static unsigned v850e_uart_tx_empty (struct uart_port *port)
+{
+	return TIOCSER_TEMT;	/* Can't detect.  */
+}
+
+static void v850e_uart_set_mctrl (struct uart_port *port, unsigned mctrl)
+{
+#ifdef V850E_UART_SET_RTS
+	V850E_UART_SET_RTS (port->line, (mctrl & TIOCM_RTS));
+#endif
+}
+
+static unsigned v850e_uart_get_mctrl (struct uart_port *port)
+{
+	/* We don't support DCD or DSR, so consider them permanently active. */
+	int mctrl = TIOCM_CAR | TIOCM_DSR;
+
+	/* We may support CTS.  */
+#ifdef V850E_UART_CTS
+	mctrl |= V850E_UART_CTS(port->line) ? TIOCM_CTS : 0;
+#else
+	mctrl |= TIOCM_CTS;
+#endif
+
+	return mctrl;
+}
+
+static void v850e_uart_start_tx (struct uart_port *port, unsigned tty_start)
+{
+	v850e_intc_disable_irq (V850E_UART_TX_IRQ (port->line));
+	v850e_uart_tx (port);
+	v850e_intc_enable_irq (V850E_UART_TX_IRQ (port->line));
+}
+
+static void v850e_uart_stop_tx (struct uart_port *port, unsigned tty_stop)
+{
+	v850e_intc_disable_irq (V850E_UART_TX_IRQ (port->line));
+}
+
+static void v850e_uart_start_rx (struct uart_port *port)
+{
+	v850e_intc_enable_irq (V850E_UART_RX_IRQ (port->line));
+}
+
+static void v850e_uart_stop_rx (struct uart_port *port)
+{
+	v850e_intc_disable_irq (V850E_UART_RX_IRQ (port->line));
+}
+
+static void v850e_uart_break_ctl (struct uart_port *port, int break_ctl)
+{
+	/* Umm, do this later.  */
+}
+
+static int v850e_uart_startup (struct uart_port *port)
+{
+	int err;
+
+	/* Alloc RX irq.  */
+	err = request_irq (V850E_UART_RX_IRQ (port->line), v850e_uart_rx_irq,
+			   SA_INTERRUPT, "v850e_uart", port);
+	if (err)
+		return err;
+
+	/* Alloc TX irq.  */
+	err = request_irq (V850E_UART_TX_IRQ (port->line), v850e_uart_tx_irq,
+			   SA_INTERRUPT, "v850e_uart", port);
+	if (err) {
+		free_irq (V850E_UART_RX_IRQ (port->line), port);
+		return err;
+	}
+
+	v850e_uart_start_rx (port);
+
+	return 0;
+}
+
+static void v850e_uart_shutdown (struct uart_port *port)
+{
+	/* Disable port interrupts.  */
+	free_irq (V850E_UART_TX_IRQ (port->line), port);
+	free_irq (V850E_UART_RX_IRQ (port->line), port);
+
+	/* Turn off xmit/recv enable bits.  */
+	V850E_UART_CONFIG (port->line)
+		&= ~(V850E_UART_CONFIG_TX_ENABLE
+		     | V850E_UART_CONFIG_RX_ENABLE);
+	/* Then reset the channel.  */
+	V850E_UART_CONFIG (port->line) = 0;
+}
+
+static void
+v850e_uart_set_termios (struct uart_port *port, struct termios *termios,
+		        struct termios *old)
+{
+	unsigned cflags = termios->c_cflag;
+
+	/* Restrict flags to legal values.  */
+	if ((cflags & CSIZE) != CS7 && (cflags & CSIZE) != CS8)
+		/* The new value of CSIZE is invalid, use the old value.  */
+		cflags = (cflags & ~CSIZE)
+			| (old ? (old->c_cflag & CSIZE) : CS8);
+
+	termios->c_cflag = cflags;
+
+	v850e_uart_configure (port->line, cflags,
+			      uart_get_baud_rate (port, termios, old,
+						  v850e_uart_min_baud(),
+						  v850e_uart_max_baud()));
+}
+
+static const char *v850e_uart_type (struct uart_port *port)
+{
+	return port->type == PORT_V850E_UART ? "v850e_uart" : 0;
+}
+
+static void v850e_uart_config_port (struct uart_port *port, int flags)
+{
+	if (flags & UART_CONFIG_TYPE)
+		port->type = PORT_V850E_UART;
+}
+
+static int
+v850e_uart_verify_port (struct uart_port *port, struct serial_struct *ser)
+{
+	if (ser->type != PORT_UNKNOWN && ser->type != PORT_V850E_UART)
+		return -EINVAL;
+	if (ser->irq != V850E_UART_TX_IRQ (port->line))
+		return -EINVAL;
+	return 0;
+}
+
+static struct uart_ops v850e_uart_ops = {
+	.tx_empty	= v850e_uart_tx_empty,
+	.get_mctrl	= v850e_uart_get_mctrl,
+	.set_mctrl	= v850e_uart_set_mctrl,
+	.start_tx	= v850e_uart_start_tx,
+	.stop_tx	= v850e_uart_stop_tx,
+	.stop_rx	= v850e_uart_stop_rx,
+	.enable_ms	= v850e_uart_nop,
+	.break_ctl	= v850e_uart_break_ctl,
+	.startup	= v850e_uart_startup,
+	.shutdown	= v850e_uart_shutdown,
+	.set_termios	= v850e_uart_set_termios,
+	.type		= v850e_uart_type,
+	.release_port	= v850e_uart_nop,
+	.request_port	= v850e_uart_success,
+	.config_port	= v850e_uart_config_port,
+	.verify_port	= v850e_uart_verify_port,
+};
+
+/* Initialization and cleanup.  */
+
+static struct uart_driver v850e_uart_driver = {
+	.owner			= THIS_MODULE,
+	.driver_name		= "v850e_uart",
+	.devfs_name		= "tts/",
+	.dev_name		= "ttyS",
+	.major			= TTY_MAJOR,
+	.minor			= V850E_UART_MINOR_BASE,
+	.nr			= V850E_UART_NUM_CHANNELS,
+	.cons			= V850E_UART_CONSOLE,
+};
+
+
+static struct uart_port v850e_uart_ports[V850E_UART_NUM_CHANNELS];
+
+static int __init v850e_uart_init (void)
+{
+	int rval;
+
+	printk (KERN_INFO "%s on-chip UART\n", V850E_UART_CHIP_NAME);
+
+	rval = uart_register_driver (&v850e_uart_driver);
+	if (rval == 0) {
+		unsigned chan;
+
+		for (chan = 0; chan < V850E_UART_NUM_CHANNELS; chan++) {
+			struct uart_port *port = &v850e_uart_ports[chan];
+			
+			memset (port, 0, sizeof *port);
+
+			port->ops = &v850e_uart_ops;
+			port->line = chan;
+			port->iotype = SERIAL_IO_MEM;
+			port->flags = UPF_BOOT_AUTOCONF;
+
+			/* We actually use multiple IRQs, but the serial
+			   framework seems to mainly use this for
+			   informational purposes anyway.  Here we use the TX
+			   irq.  */
+			port->irq = V850E_UART_TX_IRQ (chan);
+
+			/* The serial framework doesn't really use these
+			   membase/mapbase fields for anything useful, but
+			   it requires that they be something non-zero to
+			   consider the port `valid', and also uses them
+			   for informational purposes.  */
+			port->membase = (void *)V850E_UART_BASE_ADDR (chan);
+			port->mapbase = V850E_UART_BASE_ADDR (chan);
+
+			/* The framework insists on knowing the uart's master
+			   clock freq, though it doesn't seem to do anything
+			   useful for us with it.  We must make it at least
+			   higher than (the maximum baud rate * 16), otherwise
+			   the framework will puke during its internal
+			   calculations, and force the baud rate to be 9600.
+			   To be accurate though, just repeat the calculation
+			   we use when actually setting the speed.  */
+			port->uartclk = v850e_uart_max_clock() * 16;
+
+			uart_add_one_port (&v850e_uart_driver, port);
+		}
+	}
+
+	return rval;
+}
+
+static void __exit v850e_uart_exit (void)
+{
+	unsigned chan;
+
+	for (chan = 0; chan < V850E_UART_NUM_CHANNELS; chan++)
+		uart_remove_one_port (&v850e_uart_driver,
+				      &v850e_uart_ports[chan]);
+
+	uart_unregister_driver (&v850e_uart_driver);
+}
+
+module_init (v850e_uart_init);
+module_exit (v850e_uart_exit);
+
+MODULE_AUTHOR ("Miles Bader");
+MODULE_DESCRIPTION ("NEC " V850E_UART_CHIP_NAME " on-chip UART");
+MODULE_LICENSE ("GPL");