diff options
Diffstat (limited to 'drivers/tty/serial/mcf.c')
| -rw-r--r-- | drivers/tty/serial/mcf.c | 705 |
1 files changed, 705 insertions, 0 deletions
diff --git a/drivers/tty/serial/mcf.c b/drivers/tty/serial/mcf.c new file mode 100644 index 000000000..7dbfb4cde --- /dev/null +++ b/drivers/tty/serial/mcf.c @@ -0,0 +1,705 @@ +// SPDX-License-Identifier: GPL-2.0+ +/****************************************************************************/ + +/* + * mcf.c -- Freescale ColdFire UART driver + * + * (C) Copyright 2003-2007, Greg Ungerer <gerg@uclinux.org> + */ + +/****************************************************************************/ + +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/interrupt.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 <linux/io.h> +#include <linux/uaccess.h> +#include <linux/platform_device.h> +#include <asm/coldfire.h> +#include <asm/mcfsim.h> +#include <asm/mcfuart.h> +#include <asm/nettel.h> + +/****************************************************************************/ + +/* + * Some boards implement the DTR/DCD lines using GPIO lines, most + * don't. Dummy out the access macros for those that don't. Those + * that do should define these macros somewhere in there board + * specific inlude files. + */ +#if !defined(mcf_getppdcd) +#define mcf_getppdcd(p) (1) +#endif +#if !defined(mcf_getppdtr) +#define mcf_getppdtr(p) (1) +#endif +#if !defined(mcf_setppdtr) +#define mcf_setppdtr(p, v) do { } while (0) +#endif + +/****************************************************************************/ + +/* + * Local per-uart structure. + */ +struct mcf_uart { + struct uart_port port; + unsigned int sigs; /* Local copy of line sigs */ + unsigned char imr; /* Local IMR mirror */ +}; + +/****************************************************************************/ + +static unsigned int mcf_tx_empty(struct uart_port *port) +{ + return (readb(port->membase + MCFUART_USR) & MCFUART_USR_TXEMPTY) ? + TIOCSER_TEMT : 0; +} + +/****************************************************************************/ + +static unsigned int mcf_get_mctrl(struct uart_port *port) +{ + struct mcf_uart *pp = container_of(port, struct mcf_uart, port); + unsigned int sigs; + + sigs = (readb(port->membase + MCFUART_UIPR) & MCFUART_UIPR_CTS) ? + 0 : TIOCM_CTS; + sigs |= (pp->sigs & TIOCM_RTS); + sigs |= (mcf_getppdcd(port->line) ? TIOCM_CD : 0); + sigs |= (mcf_getppdtr(port->line) ? TIOCM_DTR : 0); + + return sigs; +} + +/****************************************************************************/ + +static void mcf_set_mctrl(struct uart_port *port, unsigned int sigs) +{ + struct mcf_uart *pp = container_of(port, struct mcf_uart, port); + + pp->sigs = sigs; + mcf_setppdtr(port->line, (sigs & TIOCM_DTR)); + if (sigs & TIOCM_RTS) + writeb(MCFUART_UOP_RTS, port->membase + MCFUART_UOP1); + else + writeb(MCFUART_UOP_RTS, port->membase + MCFUART_UOP0); +} + +/****************************************************************************/ + +static void mcf_start_tx(struct uart_port *port) +{ + struct mcf_uart *pp = container_of(port, struct mcf_uart, port); + + if (port->rs485.flags & SER_RS485_ENABLED) { + /* Enable Transmitter */ + writeb(MCFUART_UCR_TXENABLE, port->membase + MCFUART_UCR); + /* Manually assert RTS */ + writeb(MCFUART_UOP_RTS, port->membase + MCFUART_UOP1); + } + pp->imr |= MCFUART_UIR_TXREADY; + writeb(pp->imr, port->membase + MCFUART_UIMR); +} + +/****************************************************************************/ + +static void mcf_stop_tx(struct uart_port *port) +{ + struct mcf_uart *pp = container_of(port, struct mcf_uart, port); + + pp->imr &= ~MCFUART_UIR_TXREADY; + writeb(pp->imr, port->membase + MCFUART_UIMR); +} + +/****************************************************************************/ + +static void mcf_stop_rx(struct uart_port *port) +{ + struct mcf_uart *pp = container_of(port, struct mcf_uart, port); + + pp->imr &= ~MCFUART_UIR_RXREADY; + writeb(pp->imr, port->membase + MCFUART_UIMR); +} + +/****************************************************************************/ + +static void mcf_break_ctl(struct uart_port *port, int break_state) +{ + unsigned long flags; + + spin_lock_irqsave(&port->lock, flags); + if (break_state == -1) + writeb(MCFUART_UCR_CMDBREAKSTART, port->membase + MCFUART_UCR); + else + writeb(MCFUART_UCR_CMDBREAKSTOP, port->membase + MCFUART_UCR); + spin_unlock_irqrestore(&port->lock, flags); +} + +/****************************************************************************/ + +static int mcf_startup(struct uart_port *port) +{ + struct mcf_uart *pp = container_of(port, struct mcf_uart, port); + unsigned long flags; + + spin_lock_irqsave(&port->lock, flags); + + /* Reset UART, get it into known state... */ + writeb(MCFUART_UCR_CMDRESETRX, port->membase + MCFUART_UCR); + writeb(MCFUART_UCR_CMDRESETTX, port->membase + MCFUART_UCR); + + /* Enable the UART transmitter and receiver */ + writeb(MCFUART_UCR_RXENABLE | MCFUART_UCR_TXENABLE, + port->membase + MCFUART_UCR); + + /* Enable RX interrupts now */ + pp->imr = MCFUART_UIR_RXREADY; + writeb(pp->imr, port->membase + MCFUART_UIMR); + + spin_unlock_irqrestore(&port->lock, flags); + + return 0; +} + +/****************************************************************************/ + +static void mcf_shutdown(struct uart_port *port) +{ + struct mcf_uart *pp = container_of(port, struct mcf_uart, port); + unsigned long flags; + + spin_lock_irqsave(&port->lock, flags); + + /* Disable all interrupts now */ + pp->imr = 0; + writeb(pp->imr, port->membase + MCFUART_UIMR); + + /* Disable UART transmitter and receiver */ + writeb(MCFUART_UCR_CMDRESETRX, port->membase + MCFUART_UCR); + writeb(MCFUART_UCR_CMDRESETTX, port->membase + MCFUART_UCR); + + spin_unlock_irqrestore(&port->lock, flags); +} + +/****************************************************************************/ + +static void mcf_set_termios(struct uart_port *port, struct ktermios *termios, + struct ktermios *old) +{ + unsigned long flags; + unsigned int baud, baudclk; +#if defined(CONFIG_M5272) + unsigned int baudfr; +#endif + unsigned char mr1, mr2; + + baud = uart_get_baud_rate(port, termios, old, 0, 230400); +#if defined(CONFIG_M5272) + baudclk = (MCF_BUSCLK / baud) / 32; + baudfr = (((MCF_BUSCLK / baud) + 1) / 2) % 16; +#else + baudclk = ((MCF_BUSCLK / baud) + 16) / 32; +#endif + + mr1 = MCFUART_MR1_RXIRQRDY | MCFUART_MR1_RXERRCHAR; + mr2 = 0; + + switch (termios->c_cflag & CSIZE) { + case CS5: mr1 |= MCFUART_MR1_CS5; break; + case CS6: mr1 |= MCFUART_MR1_CS6; break; + case CS7: mr1 |= MCFUART_MR1_CS7; break; + case CS8: + default: mr1 |= MCFUART_MR1_CS8; break; + } + + if (termios->c_cflag & PARENB) { + if (termios->c_cflag & CMSPAR) { + if (termios->c_cflag & PARODD) + mr1 |= MCFUART_MR1_PARITYMARK; + else + mr1 |= MCFUART_MR1_PARITYSPACE; + } else { + if (termios->c_cflag & PARODD) + mr1 |= MCFUART_MR1_PARITYODD; + else + mr1 |= MCFUART_MR1_PARITYEVEN; + } + } else { + mr1 |= MCFUART_MR1_PARITYNONE; + } + + /* + * FIXME: port->read_status_mask and port->ignore_status_mask + * need to be initialized based on termios settings for + * INPCK, IGNBRK, IGNPAR, PARMRK, BRKINT + */ + + if (termios->c_cflag & CSTOPB) + mr2 |= MCFUART_MR2_STOP2; + else + mr2 |= MCFUART_MR2_STOP1; + + if (termios->c_cflag & CRTSCTS) { + mr1 |= MCFUART_MR1_RXRTS; + mr2 |= MCFUART_MR2_TXCTS; + } + + spin_lock_irqsave(&port->lock, flags); + if (port->rs485.flags & SER_RS485_ENABLED) { + dev_dbg(port->dev, "Setting UART to RS485\n"); + mr2 |= MCFUART_MR2_TXRTS; + } + + uart_update_timeout(port, termios->c_cflag, baud); + writeb(MCFUART_UCR_CMDRESETRX, port->membase + MCFUART_UCR); + writeb(MCFUART_UCR_CMDRESETTX, port->membase + MCFUART_UCR); + writeb(MCFUART_UCR_CMDRESETMRPTR, port->membase + MCFUART_UCR); + writeb(mr1, port->membase + MCFUART_UMR); + writeb(mr2, port->membase + MCFUART_UMR); + writeb((baudclk & 0xff00) >> 8, port->membase + MCFUART_UBG1); + writeb((baudclk & 0xff), port->membase + MCFUART_UBG2); +#if defined(CONFIG_M5272) + writeb((baudfr & 0x0f), port->membase + MCFUART_UFPD); +#endif + writeb(MCFUART_UCSR_RXCLKTIMER | MCFUART_UCSR_TXCLKTIMER, + port->membase + MCFUART_UCSR); + writeb(MCFUART_UCR_RXENABLE | MCFUART_UCR_TXENABLE, + port->membase + MCFUART_UCR); + spin_unlock_irqrestore(&port->lock, flags); +} + +/****************************************************************************/ + +static void mcf_rx_chars(struct mcf_uart *pp) +{ + struct uart_port *port = &pp->port; + unsigned char status, ch, flag; + + while ((status = readb(port->membase + MCFUART_USR)) & MCFUART_USR_RXREADY) { + ch = readb(port->membase + MCFUART_URB); + flag = TTY_NORMAL; + port->icount.rx++; + + if (status & MCFUART_USR_RXERR) { + writeb(MCFUART_UCR_CMDRESETERR, + port->membase + MCFUART_UCR); + + if (status & MCFUART_USR_RXBREAK) { + port->icount.brk++; + if (uart_handle_break(port)) + continue; + } else if (status & MCFUART_USR_RXPARITY) { + port->icount.parity++; + } else if (status & MCFUART_USR_RXOVERRUN) { + port->icount.overrun++; + } else if (status & MCFUART_USR_RXFRAMING) { + port->icount.frame++; + } + + status &= port->read_status_mask; + + if (status & MCFUART_USR_RXBREAK) + flag = TTY_BREAK; + else if (status & MCFUART_USR_RXPARITY) + flag = TTY_PARITY; + else if (status & MCFUART_USR_RXFRAMING) + flag = TTY_FRAME; + } + + if (uart_handle_sysrq_char(port, ch)) + continue; + uart_insert_char(port, status, MCFUART_USR_RXOVERRUN, ch, flag); + } + + spin_unlock(&port->lock); + tty_flip_buffer_push(&port->state->port); + spin_lock(&port->lock); +} + +/****************************************************************************/ + +static void mcf_tx_chars(struct mcf_uart *pp) +{ + struct uart_port *port = &pp->port; + struct circ_buf *xmit = &port->state->xmit; + + if (port->x_char) { + /* Send special char - probably flow control */ + writeb(port->x_char, port->membase + MCFUART_UTB); + port->x_char = 0; + port->icount.tx++; + return; + } + + while (readb(port->membase + MCFUART_USR) & MCFUART_USR_TXREADY) { + if (xmit->head == xmit->tail) + break; + writeb(xmit->buf[xmit->tail], port->membase + MCFUART_UTB); + xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE -1); + port->icount.tx++; + } + + if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) + uart_write_wakeup(port); + + if (xmit->head == xmit->tail) { + pp->imr &= ~MCFUART_UIR_TXREADY; + writeb(pp->imr, port->membase + MCFUART_UIMR); + /* Disable TX to negate RTS automatically */ + if (port->rs485.flags & SER_RS485_ENABLED) + writeb(MCFUART_UCR_TXDISABLE, + port->membase + MCFUART_UCR); + } +} + +/****************************************************************************/ + +static irqreturn_t mcf_interrupt(int irq, void *data) +{ + struct uart_port *port = data; + struct mcf_uart *pp = container_of(port, struct mcf_uart, port); + unsigned int isr; + irqreturn_t ret = IRQ_NONE; + + isr = readb(port->membase + MCFUART_UISR) & pp->imr; + + spin_lock(&port->lock); + if (isr & MCFUART_UIR_RXREADY) { + mcf_rx_chars(pp); + ret = IRQ_HANDLED; + } + if (isr & MCFUART_UIR_TXREADY) { + mcf_tx_chars(pp); + ret = IRQ_HANDLED; + } + spin_unlock(&port->lock); + + return ret; +} + +/****************************************************************************/ + +static void mcf_config_port(struct uart_port *port, int flags) +{ + port->type = PORT_MCF; + port->fifosize = MCFUART_TXFIFOSIZE; + + /* Clear mask, so no surprise interrupts. */ + writeb(0, port->membase + MCFUART_UIMR); + + if (request_irq(port->irq, mcf_interrupt, 0, "UART", port)) + printk(KERN_ERR "MCF: unable to attach ColdFire UART %d " + "interrupt vector=%d\n", port->line, port->irq); +} + +/****************************************************************************/ + +static const char *mcf_type(struct uart_port *port) +{ + return (port->type == PORT_MCF) ? "ColdFire UART" : NULL; +} + +/****************************************************************************/ + +static int mcf_request_port(struct uart_port *port) +{ + /* UARTs always present */ + return 0; +} + +/****************************************************************************/ + +static void mcf_release_port(struct uart_port *port) +{ + /* Nothing to release... */ +} + +/****************************************************************************/ + +static int mcf_verify_port(struct uart_port *port, struct serial_struct *ser) +{ + if ((ser->type != PORT_UNKNOWN) && (ser->type != PORT_MCF)) + return -EINVAL; + return 0; +} + +/****************************************************************************/ + +/* Enable or disable the RS485 support */ +static int mcf_config_rs485(struct uart_port *port, struct serial_rs485 *rs485) +{ + unsigned char mr1, mr2; + + /* Get mode registers */ + mr1 = readb(port->membase + MCFUART_UMR); + mr2 = readb(port->membase + MCFUART_UMR); + if (rs485->flags & SER_RS485_ENABLED) { + dev_dbg(port->dev, "Setting UART to RS485\n"); + /* Automatically negate RTS after TX completes */ + mr2 |= MCFUART_MR2_TXRTS; + } else { + dev_dbg(port->dev, "Setting UART to RS232\n"); + mr2 &= ~MCFUART_MR2_TXRTS; + } + writeb(mr1, port->membase + MCFUART_UMR); + writeb(mr2, port->membase + MCFUART_UMR); + port->rs485 = *rs485; + + return 0; +} + +/****************************************************************************/ + +/* + * Define the basic serial functions we support. + */ +static const struct uart_ops mcf_uart_ops = { + .tx_empty = mcf_tx_empty, + .get_mctrl = mcf_get_mctrl, + .set_mctrl = mcf_set_mctrl, + .start_tx = mcf_start_tx, + .stop_tx = mcf_stop_tx, + .stop_rx = mcf_stop_rx, + .break_ctl = mcf_break_ctl, + .startup = mcf_startup, + .shutdown = mcf_shutdown, + .set_termios = mcf_set_termios, + .type = mcf_type, + .request_port = mcf_request_port, + .release_port = mcf_release_port, + .config_port = mcf_config_port, + .verify_port = mcf_verify_port, +}; + +static struct mcf_uart mcf_ports[4]; + +#define MCF_MAXPORTS ARRAY_SIZE(mcf_ports) + +/****************************************************************************/ +#if defined(CONFIG_SERIAL_MCF_CONSOLE) +/****************************************************************************/ + +int __init early_mcf_setup(struct mcf_platform_uart *platp) +{ + struct uart_port *port; + int i; + + for (i = 0; ((i < MCF_MAXPORTS) && (platp[i].mapbase)); i++) { + port = &mcf_ports[i].port; + + port->line = i; + port->type = PORT_MCF; + port->mapbase = platp[i].mapbase; + port->membase = (platp[i].membase) ? platp[i].membase : + (unsigned char __iomem *) port->mapbase; + port->iotype = SERIAL_IO_MEM; + port->irq = platp[i].irq; + port->uartclk = MCF_BUSCLK; + port->flags = UPF_BOOT_AUTOCONF; + port->rs485_config = mcf_config_rs485; + port->ops = &mcf_uart_ops; + } + + return 0; +} + +/****************************************************************************/ + +static void mcf_console_putc(struct console *co, const char c) +{ + struct uart_port *port = &(mcf_ports + co->index)->port; + int i; + + for (i = 0; (i < 0x10000); i++) { + if (readb(port->membase + MCFUART_USR) & MCFUART_USR_TXREADY) + break; + } + writeb(c, port->membase + MCFUART_UTB); + for (i = 0; (i < 0x10000); i++) { + if (readb(port->membase + MCFUART_USR) & MCFUART_USR_TXREADY) + break; + } +} + +/****************************************************************************/ + +static void mcf_console_write(struct console *co, const char *s, unsigned int count) +{ + for (; (count); count--, s++) { + mcf_console_putc(co, *s); + if (*s == '\n') + mcf_console_putc(co, '\r'); + } +} + +/****************************************************************************/ + +static int __init mcf_console_setup(struct console *co, char *options) +{ + struct uart_port *port; + int baud = CONFIG_SERIAL_MCF_BAUDRATE; + int bits = 8; + int parity = 'n'; + int flow = 'n'; + + if ((co->index < 0) || (co->index >= MCF_MAXPORTS)) + co->index = 0; + port = &mcf_ports[co->index].port; + if (port->membase == 0) + return -ENODEV; + + if (options) + uart_parse_options(options, &baud, &parity, &bits, &flow); + + return uart_set_options(port, co, baud, parity, bits, flow); +} + +/****************************************************************************/ + +static struct uart_driver mcf_driver; + +static struct console mcf_console = { + .name = "ttyS", + .write = mcf_console_write, + .device = uart_console_device, + .setup = mcf_console_setup, + .flags = CON_PRINTBUFFER, + .index = -1, + .data = &mcf_driver, +}; + +static int __init mcf_console_init(void) +{ + register_console(&mcf_console); + return 0; +} + +console_initcall(mcf_console_init); + +#define MCF_CONSOLE &mcf_console + +/****************************************************************************/ +#else +/****************************************************************************/ + +#define MCF_CONSOLE NULL + +/****************************************************************************/ +#endif /* CONFIG_SERIAL_MCF_CONSOLE */ +/****************************************************************************/ + +/* + * Define the mcf UART driver structure. + */ +static struct uart_driver mcf_driver = { + .owner = THIS_MODULE, + .driver_name = "mcf", + .dev_name = "ttyS", + .major = TTY_MAJOR, + .minor = 64, + .nr = MCF_MAXPORTS, + .cons = MCF_CONSOLE, +}; + +/****************************************************************************/ + +static int mcf_probe(struct platform_device *pdev) +{ + struct mcf_platform_uart *platp = dev_get_platdata(&pdev->dev); + struct uart_port *port; + int i; + + for (i = 0; ((i < MCF_MAXPORTS) && (platp[i].mapbase)); i++) { + port = &mcf_ports[i].port; + + port->line = i; + port->type = PORT_MCF; + port->mapbase = platp[i].mapbase; + port->membase = (platp[i].membase) ? platp[i].membase : + (unsigned char __iomem *) platp[i].mapbase; + port->dev = &pdev->dev; + port->iotype = SERIAL_IO_MEM; + port->irq = platp[i].irq; + port->uartclk = MCF_BUSCLK; + port->ops = &mcf_uart_ops; + port->flags = UPF_BOOT_AUTOCONF; + port->rs485_config = mcf_config_rs485; + + uart_add_one_port(&mcf_driver, port); + } + + return 0; +} + +/****************************************************************************/ + +static int mcf_remove(struct platform_device *pdev) +{ + struct uart_port *port; + int i; + + for (i = 0; (i < MCF_MAXPORTS); i++) { + port = &mcf_ports[i].port; + if (port) + uart_remove_one_port(&mcf_driver, port); + } + + return 0; +} + +/****************************************************************************/ + +static struct platform_driver mcf_platform_driver = { + .probe = mcf_probe, + .remove = mcf_remove, + .driver = { + .name = "mcfuart", + }, +}; + +/****************************************************************************/ + +static int __init mcf_init(void) +{ + int rc; + + printk("ColdFire internal UART serial driver\n"); + + rc = uart_register_driver(&mcf_driver); + if (rc) + return rc; + rc = platform_driver_register(&mcf_platform_driver); + if (rc) { + uart_unregister_driver(&mcf_driver); + return rc; + } + return 0; +} + +/****************************************************************************/ + +static void __exit mcf_exit(void) +{ + platform_driver_unregister(&mcf_platform_driver); + uart_unregister_driver(&mcf_driver); +} + +/****************************************************************************/ + +module_init(mcf_init); +module_exit(mcf_exit); + +MODULE_AUTHOR("Greg Ungerer <gerg@uclinux.org>"); +MODULE_DESCRIPTION("Freescale ColdFire UART driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:mcfuart"); + +/****************************************************************************/ |