swh:1:snp:49cd9498d6cccc5e78252c27dcb645bcf7bf0c91
Tip revision: 4a6908a3a050aacc9c3a2f36b276b46c0629ad91 authored by Linus Torvalds on 24 December 2008, 23:26:37 UTC
Linux 2.6.28
Linux 2.6.28
Tip revision: 4a6908a
netx-serial.c
/*
* drivers/serial/netx-serial.c
*
* Copyright (c) 2005 Sascha Hauer <s.hauer@pengutronix.de>, Pengutronix
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2
* as published by the Free Software Foundation.
*
* 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
*/
#if defined(CONFIG_SERIAL_NETX_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
#define SUPPORT_SYSRQ
#endif
#include <linux/device.h>
#include <linux/module.h>
#include <linux/ioport.h>
#include <linux/init.h>
#include <linux/console.h>
#include <linux/sysrq.h>
#include <linux/platform_device.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/serial_core.h>
#include <linux/serial.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <mach/hardware.h>
#include <mach/netx-regs.h>
/* We've been assigned a range on the "Low-density serial ports" major */
#define SERIAL_NX_MAJOR 204
#define MINOR_START 170
enum uart_regs {
UART_DR = 0x00,
UART_SR = 0x04,
UART_LINE_CR = 0x08,
UART_BAUDDIV_MSB = 0x0c,
UART_BAUDDIV_LSB = 0x10,
UART_CR = 0x14,
UART_FR = 0x18,
UART_IIR = 0x1c,
UART_ILPR = 0x20,
UART_RTS_CR = 0x24,
UART_RTS_LEAD = 0x28,
UART_RTS_TRAIL = 0x2c,
UART_DRV_ENABLE = 0x30,
UART_BRM_CR = 0x34,
UART_RXFIFO_IRQLEVEL = 0x38,
UART_TXFIFO_IRQLEVEL = 0x3c,
};
#define SR_FE (1<<0)
#define SR_PE (1<<1)
#define SR_BE (1<<2)
#define SR_OE (1<<3)
#define LINE_CR_BRK (1<<0)
#define LINE_CR_PEN (1<<1)
#define LINE_CR_EPS (1<<2)
#define LINE_CR_STP2 (1<<3)
#define LINE_CR_FEN (1<<4)
#define LINE_CR_5BIT (0<<5)
#define LINE_CR_6BIT (1<<5)
#define LINE_CR_7BIT (2<<5)
#define LINE_CR_8BIT (3<<5)
#define LINE_CR_BITS_MASK (3<<5)
#define CR_UART_EN (1<<0)
#define CR_SIREN (1<<1)
#define CR_SIRLP (1<<2)
#define CR_MSIE (1<<3)
#define CR_RIE (1<<4)
#define CR_TIE (1<<5)
#define CR_RTIE (1<<6)
#define CR_LBE (1<<7)
#define FR_CTS (1<<0)
#define FR_DSR (1<<1)
#define FR_DCD (1<<2)
#define FR_BUSY (1<<3)
#define FR_RXFE (1<<4)
#define FR_TXFF (1<<5)
#define FR_RXFF (1<<6)
#define FR_TXFE (1<<7)
#define IIR_MIS (1<<0)
#define IIR_RIS (1<<1)
#define IIR_TIS (1<<2)
#define IIR_RTIS (1<<3)
#define IIR_MASK 0xf
#define RTS_CR_AUTO (1<<0)
#define RTS_CR_RTS (1<<1)
#define RTS_CR_COUNT (1<<2)
#define RTS_CR_MOD2 (1<<3)
#define RTS_CR_RTS_POL (1<<4)
#define RTS_CR_CTS_CTR (1<<5)
#define RTS_CR_CTS_POL (1<<6)
#define RTS_CR_STICK (1<<7)
#define UART_PORT_SIZE 0x40
#define DRIVER_NAME "netx-uart"
struct netx_port {
struct uart_port port;
};
static void netx_stop_tx(struct uart_port *port)
{
unsigned int val;
val = readl(port->membase + UART_CR);
writel(val & ~CR_TIE, port->membase + UART_CR);
}
static void netx_stop_rx(struct uart_port *port)
{
unsigned int val;
val = readl(port->membase + UART_CR);
writel(val & ~CR_RIE, port->membase + UART_CR);
}
static void netx_enable_ms(struct uart_port *port)
{
unsigned int val;
val = readl(port->membase + UART_CR);
writel(val | CR_MSIE, port->membase + UART_CR);
}
static inline void netx_transmit_buffer(struct uart_port *port)
{
struct circ_buf *xmit = &port->info->xmit;
if (port->x_char) {
writel(port->x_char, port->membase + UART_DR);
port->icount.tx++;
port->x_char = 0;
return;
}
if (uart_tx_stopped(port) || uart_circ_empty(xmit)) {
netx_stop_tx(port);
return;
}
do {
/* send xmit->buf[xmit->tail]
* out the port here */
writel(xmit->buf[xmit->tail], port->membase + UART_DR);
xmit->tail = (xmit->tail + 1) &
(UART_XMIT_SIZE - 1);
port->icount.tx++;
if (uart_circ_empty(xmit))
break;
} while (!(readl(port->membase + UART_FR) & FR_TXFF));
if (uart_circ_empty(xmit))
netx_stop_tx(port);
}
static void netx_start_tx(struct uart_port *port)
{
writel(
readl(port->membase + UART_CR) | CR_TIE, port->membase + UART_CR);
if (!(readl(port->membase + UART_FR) & FR_TXFF))
netx_transmit_buffer(port);
}
static unsigned int netx_tx_empty(struct uart_port *port)
{
return readl(port->membase + UART_FR) & FR_BUSY ? 0 : TIOCSER_TEMT;
}
static void netx_txint(struct uart_port *port)
{
struct circ_buf *xmit = &port->info->xmit;
if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
netx_stop_tx(port);
return;
}
netx_transmit_buffer(port);
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(port);
}
static void netx_rxint(struct uart_port *port)
{
unsigned char rx, flg, status;
struct tty_struct *tty = port->info->port.tty;
while (!(readl(port->membase + UART_FR) & FR_RXFE)) {
rx = readl(port->membase + UART_DR);
flg = TTY_NORMAL;
port->icount.rx++;
status = readl(port->membase + UART_SR);
if (status & SR_BE) {
writel(0, port->membase + UART_SR);
if (uart_handle_break(port))
continue;
}
if (unlikely(status & (SR_FE | SR_PE | SR_OE))) {
if (status & SR_PE)
port->icount.parity++;
else if (status & SR_FE)
port->icount.frame++;
if (status & SR_OE)
port->icount.overrun++;
status &= port->read_status_mask;
if (status & SR_BE)
flg = TTY_BREAK;
else if (status & SR_PE)
flg = TTY_PARITY;
else if (status & SR_FE)
flg = TTY_FRAME;
}
if (uart_handle_sysrq_char(port, rx))
continue;
uart_insert_char(port, status, SR_OE, rx, flg);
}
tty_flip_buffer_push(tty);
return;
}
static irqreturn_t netx_int(int irq, void *dev_id)
{
struct uart_port *port = dev_id;
unsigned long flags;
unsigned char status;
spin_lock_irqsave(&port->lock,flags);
status = readl(port->membase + UART_IIR) & IIR_MASK;
while (status) {
if (status & IIR_RIS)
netx_rxint(port);
if (status & IIR_TIS)
netx_txint(port);
if (status & IIR_MIS) {
if (readl(port->membase + UART_FR) & FR_CTS)
uart_handle_cts_change(port, 1);
else
uart_handle_cts_change(port, 0);
}
writel(0, port->membase + UART_IIR);
status = readl(port->membase + UART_IIR) & IIR_MASK;
}
spin_unlock_irqrestore(&port->lock,flags);
return IRQ_HANDLED;
}
static unsigned int netx_get_mctrl(struct uart_port *port)
{
unsigned int ret = TIOCM_DSR | TIOCM_CAR;
if (readl(port->membase + UART_FR) & FR_CTS)
ret |= TIOCM_CTS;
return ret;
}
static void netx_set_mctrl(struct uart_port *port, unsigned int mctrl)
{
unsigned int val;
/* FIXME: Locking needed ? */
if (mctrl & TIOCM_RTS) {
val = readl(port->membase + UART_RTS_CR);
writel(val | RTS_CR_RTS, port->membase + UART_RTS_CR);
}
}
static void netx_break_ctl(struct uart_port *port, int break_state)
{
unsigned int line_cr;
spin_lock_irq(&port->lock);
line_cr = readl(port->membase + UART_LINE_CR);
if (break_state != 0)
line_cr |= LINE_CR_BRK;
else
line_cr &= ~LINE_CR_BRK;
writel(line_cr, port->membase + UART_LINE_CR);
spin_unlock_irq(&port->lock);
}
static int netx_startup(struct uart_port *port)
{
int ret;
ret = request_irq(port->irq, netx_int, 0,
DRIVER_NAME, port);
if (ret) {
dev_err(port->dev, "unable to grab irq%d\n",port->irq);
goto exit;
}
writel(readl(port->membase + UART_LINE_CR) | LINE_CR_FEN,
port->membase + UART_LINE_CR);
writel(CR_MSIE | CR_RIE | CR_TIE | CR_RTIE | CR_UART_EN,
port->membase + UART_CR);
exit:
return ret;
}
static void netx_shutdown(struct uart_port *port)
{
writel(0, port->membase + UART_CR) ;
free_irq(port->irq, port);
}
static void
netx_set_termios(struct uart_port *port, struct ktermios *termios,
struct ktermios *old)
{
unsigned int baud, quot;
unsigned char old_cr;
unsigned char line_cr = LINE_CR_FEN;
unsigned char rts_cr = 0;
switch (termios->c_cflag & CSIZE) {
case CS5:
line_cr |= LINE_CR_5BIT;
break;
case CS6:
line_cr |= LINE_CR_6BIT;
break;
case CS7:
line_cr |= LINE_CR_7BIT;
break;
case CS8:
line_cr |= LINE_CR_8BIT;
break;
}
if (termios->c_cflag & CSTOPB)
line_cr |= LINE_CR_STP2;
if (termios->c_cflag & PARENB) {
line_cr |= LINE_CR_PEN;
if (!(termios->c_cflag & PARODD))
line_cr |= LINE_CR_EPS;
}
if (termios->c_cflag & CRTSCTS)
rts_cr = RTS_CR_AUTO | RTS_CR_CTS_CTR | RTS_CR_RTS_POL;
baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
quot = baud * 4096;
quot /= 1000;
quot *= 256;
quot /= 100000;
spin_lock_irq(&port->lock);
uart_update_timeout(port, termios->c_cflag, baud);
old_cr = readl(port->membase + UART_CR);
/* disable interrupts */
writel(old_cr & ~(CR_MSIE | CR_RIE | CR_TIE | CR_RTIE),
port->membase + UART_CR);
/* drain transmitter */
while (readl(port->membase + UART_FR) & FR_BUSY);
/* disable UART */
writel(old_cr & ~CR_UART_EN, port->membase + UART_CR);
/* modem status interrupts */
old_cr &= ~CR_MSIE;
if (UART_ENABLE_MS(port, termios->c_cflag))
old_cr |= CR_MSIE;
writel((quot>>8) & 0xff, port->membase + UART_BAUDDIV_MSB);
writel(quot & 0xff, port->membase + UART_BAUDDIV_LSB);
writel(line_cr, port->membase + UART_LINE_CR);
writel(rts_cr, port->membase + UART_RTS_CR);
/*
* Characters to ignore
*/
port->ignore_status_mask = 0;
if (termios->c_iflag & IGNPAR)
port->ignore_status_mask |= SR_PE;
if (termios->c_iflag & IGNBRK) {
port->ignore_status_mask |= SR_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 |= SR_PE;
}
port->read_status_mask = 0;
if (termios->c_iflag & (BRKINT | PARMRK))
port->read_status_mask |= SR_BE;
if (termios->c_iflag & INPCK)
port->read_status_mask |= SR_PE | SR_FE;
writel(old_cr, port->membase + UART_CR);
spin_unlock_irq(&port->lock);
}
static const char *netx_type(struct uart_port *port)
{
return port->type == PORT_NETX ? "NETX" : NULL;
}
static void netx_release_port(struct uart_port *port)
{
release_mem_region(port->mapbase, UART_PORT_SIZE);
}
static int netx_request_port(struct uart_port *port)
{
return request_mem_region(port->mapbase, UART_PORT_SIZE,
DRIVER_NAME) != NULL ? 0 : -EBUSY;
}
static void netx_config_port(struct uart_port *port, int flags)
{
if (flags & UART_CONFIG_TYPE && netx_request_port(port) == 0)
port->type = PORT_NETX;
}
static int
netx_verify_port(struct uart_port *port, struct serial_struct *ser)
{
int ret = 0;
if (ser->type != PORT_UNKNOWN && ser->type != PORT_NETX)
ret = -EINVAL;
return ret;
}
static struct uart_ops netx_pops = {
.tx_empty = netx_tx_empty,
.set_mctrl = netx_set_mctrl,
.get_mctrl = netx_get_mctrl,
.stop_tx = netx_stop_tx,
.start_tx = netx_start_tx,
.stop_rx = netx_stop_rx,
.enable_ms = netx_enable_ms,
.break_ctl = netx_break_ctl,
.startup = netx_startup,
.shutdown = netx_shutdown,
.set_termios = netx_set_termios,
.type = netx_type,
.release_port = netx_release_port,
.request_port = netx_request_port,
.config_port = netx_config_port,
.verify_port = netx_verify_port,
};
static struct netx_port netx_ports[] = {
{
.port = {
.type = PORT_NETX,
.iotype = UPIO_MEM,
.membase = (char __iomem *)io_p2v(NETX_PA_UART0),
.mapbase = NETX_PA_UART0,
.irq = NETX_IRQ_UART0,
.uartclk = 100000000,
.fifosize = 16,
.flags = UPF_BOOT_AUTOCONF,
.ops = &netx_pops,
.line = 0,
},
}, {
.port = {
.type = PORT_NETX,
.iotype = UPIO_MEM,
.membase = (char __iomem *)io_p2v(NETX_PA_UART1),
.mapbase = NETX_PA_UART1,
.irq = NETX_IRQ_UART1,
.uartclk = 100000000,
.fifosize = 16,
.flags = UPF_BOOT_AUTOCONF,
.ops = &netx_pops,
.line = 1,
},
}, {
.port = {
.type = PORT_NETX,
.iotype = UPIO_MEM,
.membase = (char __iomem *)io_p2v(NETX_PA_UART2),
.mapbase = NETX_PA_UART2,
.irq = NETX_IRQ_UART2,
.uartclk = 100000000,
.fifosize = 16,
.flags = UPF_BOOT_AUTOCONF,
.ops = &netx_pops,
.line = 2,
},
}
};
#ifdef CONFIG_SERIAL_NETX_CONSOLE
static void netx_console_putchar(struct uart_port *port, int ch)
{
while (readl(port->membase + UART_FR) & FR_BUSY);
writel(ch, port->membase + UART_DR);
}
static void
netx_console_write(struct console *co, const char *s, unsigned int count)
{
struct uart_port *port = &netx_ports[co->index].port;
unsigned char cr_save;
cr_save = readl(port->membase + UART_CR);
writel(cr_save | CR_UART_EN, port->membase + UART_CR);
uart_console_write(port, s, count, netx_console_putchar);
while (readl(port->membase + UART_FR) & FR_BUSY);
writel(cr_save, port->membase + UART_CR);
}
static void __init
netx_console_get_options(struct uart_port *port, int *baud,
int *parity, int *bits, int *flow)
{
unsigned char line_cr;
*baud = (readl(port->membase + UART_BAUDDIV_MSB) << 8) |
readl(port->membase + UART_BAUDDIV_LSB);
*baud *= 1000;
*baud /= 4096;
*baud *= 1000;
*baud /= 256;
*baud *= 100;
line_cr = readl(port->membase + UART_LINE_CR);
*parity = 'n';
if (line_cr & LINE_CR_PEN) {
if (line_cr & LINE_CR_EPS)
*parity = 'e';
else
*parity = 'o';
}
switch (line_cr & LINE_CR_BITS_MASK) {
case LINE_CR_8BIT:
*bits = 8;
break;
case LINE_CR_7BIT:
*bits = 7;
break;
case LINE_CR_6BIT:
*bits = 6;
break;
case LINE_CR_5BIT:
*bits = 5;
break;
}
if (readl(port->membase + UART_RTS_CR) & RTS_CR_AUTO)
*flow = 'r';
}
static int __init
netx_console_setup(struct console *co, char *options)
{
struct netx_port *sport;
int baud = 9600;
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 == -1 || co->index >= ARRAY_SIZE(netx_ports))
co->index = 0;
sport = &netx_ports[co->index];
if (options) {
uart_parse_options(options, &baud, &parity, &bits, &flow);
} else {
/* if the UART is enabled, assume it has been correctly setup
* by the bootloader and get the options
*/
if (readl(sport->port.membase + UART_CR) & CR_UART_EN) {
netx_console_get_options(&sport->port, &baud,
&parity, &bits, &flow);
}
}
return uart_set_options(&sport->port, co, baud, parity, bits, flow);
}
static struct uart_driver netx_reg;
static struct console netx_console = {
.name = "ttyNX",
.write = netx_console_write,
.device = uart_console_device,
.setup = netx_console_setup,
.flags = CON_PRINTBUFFER,
.index = -1,
.data = &netx_reg,
};
static int __init netx_console_init(void)
{
register_console(&netx_console);
return 0;
}
console_initcall(netx_console_init);
#define NETX_CONSOLE &netx_console
#else
#define NETX_CONSOLE NULL
#endif
static struct uart_driver netx_reg = {
.owner = THIS_MODULE,
.driver_name = DRIVER_NAME,
.dev_name = "ttyNX",
.major = SERIAL_NX_MAJOR,
.minor = MINOR_START,
.nr = ARRAY_SIZE(netx_ports),
.cons = NETX_CONSOLE,
};
static int serial_netx_suspend(struct platform_device *pdev, pm_message_t state)
{
struct netx_port *sport = platform_get_drvdata(pdev);
if (sport)
uart_suspend_port(&netx_reg, &sport->port);
return 0;
}
static int serial_netx_resume(struct platform_device *pdev)
{
struct netx_port *sport = platform_get_drvdata(pdev);
if (sport)
uart_resume_port(&netx_reg, &sport->port);
return 0;
}
static int serial_netx_probe(struct platform_device *pdev)
{
struct uart_port *port = &netx_ports[pdev->id].port;
dev_info(&pdev->dev, "initialising\n");
port->dev = &pdev->dev;
writel(1, port->membase + UART_RXFIFO_IRQLEVEL);
uart_add_one_port(&netx_reg, &netx_ports[pdev->id].port);
platform_set_drvdata(pdev, &netx_ports[pdev->id]);
return 0;
}
static int serial_netx_remove(struct platform_device *pdev)
{
struct netx_port *sport = platform_get_drvdata(pdev);
platform_set_drvdata(pdev, NULL);
if (sport)
uart_remove_one_port(&netx_reg, &sport->port);
return 0;
}
static struct platform_driver serial_netx_driver = {
.probe = serial_netx_probe,
.remove = serial_netx_remove,
.suspend = serial_netx_suspend,
.resume = serial_netx_resume,
.driver = {
.name = DRIVER_NAME,
.owner = THIS_MODULE,
},
};
static int __init netx_serial_init(void)
{
int ret;
printk(KERN_INFO "Serial: NetX driver\n");
ret = uart_register_driver(&netx_reg);
if (ret)
return ret;
ret = platform_driver_register(&serial_netx_driver);
if (ret != 0)
uart_unregister_driver(&netx_reg);
return 0;
}
static void __exit netx_serial_exit(void)
{
platform_driver_unregister(&serial_netx_driver);
uart_unregister_driver(&netx_reg);
}
module_init(netx_serial_init);
module_exit(netx_serial_exit);
MODULE_AUTHOR("Sascha Hauer");
MODULE_DESCRIPTION("NetX serial port driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:" DRIVER_NAME);