diff options
Diffstat (limited to 'drivers/serial/v850e_uart.c')
| -rw-r--r-- | drivers/serial/v850e_uart.c | 548 |
1 files changed, 0 insertions, 548 deletions
diff --git a/drivers/serial/v850e_uart.c b/drivers/serial/v850e_uart.c deleted file mode 100644 index dd98aca6ed08..000000000000 --- a/drivers/serial/v850e_uart.c +++ /dev/null @@ -1,548 +0,0 @@ -/* - * 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); - -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 uart_port *port = data; - v850e_uart_tx (port); - return IRQ_HANDLED; -} - -static irqreturn_t v850e_uart_rx_irq(int irq, void *data) -{ - 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) -{ - 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) -{ - 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, - IRQF_DISABLED, "v850e_uart", port); - if (err) - return err; - - /* Alloc TX irq. */ - err = request_irq (V850E_UART_TX_IRQ (port->line), v850e_uart_tx_irq, - IRQF_DISABLED, "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 ktermios *termios, - struct ktermios *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", - .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 = UPIO_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"); |
