openwrtv4/target/linux/ifxmips/files/drivers/serial/ifxmips_asc.c

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/*
* Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
*
* 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
*
* Copyright (C) 2004 Infineon IFAP DC COM CPE
* Copyright (C) 2007 Felix Fietkau <nbd@openwrt.org>
* Copyright (C) 2007 John Crispin <blogic@openwrt.org>
*/
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/interrupt.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/major.h>
#include <linux/string.h>
#include <linux/fcntl.h>
#include <linux/ptrace.h>
#include <linux/ioport.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/circ_buf.h>
#include <linux/serial.h>
#include <linux/serial_core.h>
#include <linux/console.h>
#include <linux/sysrq.h>
#include <linux/irq.h>
#include <linux/platform_device.h>
#include <asm/system.h>
#include <asm/io.h>
#include <asm/uaccess.h>
#include <asm/bitops.h>
#include <asm/ifxmips/ifxmips.h>
#include <asm/ifxmips/ifxmips_irq.h>
#define PORT_IFXMIPSASC 111
#include <linux/serial_core.h>
#define UART_DUMMY_UER_RX 1
static void ifxmipsasc_tx_chars(struct uart_port *port);
extern void prom_printf(const char * fmt, ...);
static struct uart_port ifxmipsasc_port[2];
static struct uart_driver ifxmipsasc_reg;
extern unsigned int ifxmips_get_fpi_hz(void);
static void
ifxmipsasc_stop_tx(struct uart_port *port)
{
return;
}
static void
ifxmipsasc_start_tx(struct uart_port *port)
{
unsigned long flags;
local_irq_save(flags);
ifxmipsasc_tx_chars(port);
local_irq_restore(flags);
return;
}
static void
ifxmipsasc_stop_rx(struct uart_port *port)
{
ifxmips_w32(ASCWHBSTATE_CLRREN, port->membase + IFXMIPS_ASC_WHBSTATE);
}
static void
ifxmipsasc_enable_ms(struct uart_port *port)
{
}
static void
ifxmipsasc_rx_chars(struct uart_port *port)
{
struct tty_struct *tty = port->info->tty;
unsigned int ch = 0, rsr = 0, fifocnt;
fifocnt = ifxmips_r32(port->membase + IFXMIPS_ASC_FSTAT) & ASCFSTAT_RXFFLMASK;
while(fifocnt--)
{
u8 flag = TTY_NORMAL;
ch = ifxmips_r32(port->membase + IFXMIPS_ASC_RBUF);
rsr = (ifxmips_r32(port->membase + IFXMIPS_ASC_STATE) & ASCSTATE_ANY) | UART_DUMMY_UER_RX;
tty_flip_buffer_push(tty);
port->icount.rx++;
/*
* Note that the error handling code is
* out of the main execution path
*/
if(rsr & ASCSTATE_ANY)
{
if(rsr & ASCSTATE_PE)
{
port->icount.parity++;
ifxmips_w32(ifxmips_r32(port->membase + IFXMIPS_ASC_WHBSTATE) | ASCWHBSTATE_CLRPE, port->membase + IFXMIPS_ASC_WHBSTATE);
} else if(rsr & ASCSTATE_FE)
{
port->icount.frame++;
ifxmips_w32(ifxmips_r32(port->membase + IFXMIPS_ASC_WHBSTATE) | ASCWHBSTATE_CLRFE, port->membase + IFXMIPS_ASC_WHBSTATE);
}
if(rsr & ASCSTATE_ROE)
{
port->icount.overrun++;
ifxmips_w32(ifxmips_r32(port->membase + IFXMIPS_ASC_WHBSTATE) | ASCWHBSTATE_CLRROE, port->membase + IFXMIPS_ASC_WHBSTATE);
}
rsr &= port->read_status_mask;
if(rsr & ASCSTATE_PE)
flag = TTY_PARITY;
else if(rsr & ASCSTATE_FE)
flag = TTY_FRAME;
}
if((rsr & port->ignore_status_mask) == 0)
tty_insert_flip_char(tty, ch, flag);
if(rsr & ASCSTATE_ROE)
/*
* Overrun is special, since it's reported
* immediately, and doesn't affect the current
* character
*/
tty_insert_flip_char(tty, 0, TTY_OVERRUN);
}
if(ch != 0)
tty_flip_buffer_push(tty);
return;
}
static void
ifxmipsasc_tx_chars(struct uart_port *port)
{
struct circ_buf *xmit = &port->info->xmit;
if(uart_tx_stopped(port))
{
ifxmipsasc_stop_tx(port);
return;
}
while(((ifxmips_r32(port->membase + IFXMIPS_ASC_FSTAT) & ASCFSTAT_TXFFLMASK)
>> ASCFSTAT_TXFFLOFF) != TXFIFO_FULL)
{
if(port->x_char)
{
ifxmips_w32(port->x_char, port->membase + IFXMIPS_ASC_TBUF);
port->icount.tx++;
port->x_char = 0;
continue;
}
if(uart_circ_empty(xmit))
break;
ifxmips_w32(port->info->xmit.buf[port->info->xmit.tail], port->membase + IFXMIPS_ASC_TBUF);
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
port->icount.tx++;
}
if(uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(port);
}
static irqreturn_t
ifxmipsasc_tx_int(int irq, void *_port)
{
struct uart_port *port = (struct uart_port*) _port;
ifxmips_w32(ASC_IRNCR_TIR, port->membase + IFXMIPS_ASC_IRNCR);
ifxmipsasc_start_tx(port);
ifxmips_mask_and_ack_irq(irq);
return IRQ_HANDLED;
}
static irqreturn_t
ifxmipsasc_er_int(int irq, void *_port)
{
struct uart_port *port = (struct uart_port*) _port;
/* clear any pending interrupts */
ifxmips_w32(ifxmips_r32(port->membase + IFXMIPS_ASC_WHBSTATE) | ASCWHBSTATE_CLRPE |
ASCWHBSTATE_CLRFE | ASCWHBSTATE_CLRROE, port->membase + IFXMIPS_ASC_WHBSTATE);
return IRQ_HANDLED;
}
static irqreturn_t
ifxmipsasc_rx_int(int irq, void *_port)
{
struct uart_port *port = (struct uart_port*)_port;
ifxmips_w32(ASC_IRNCR_RIR, port->membase + IFXMIPS_ASC_IRNCR);
ifxmipsasc_rx_chars((struct uart_port*)port);
ifxmips_mask_and_ack_irq(irq);
return IRQ_HANDLED;
}
static unsigned int
ifxmipsasc_tx_empty(struct uart_port *port)
{
int status;
status = ifxmips_r32(port->membase + IFXMIPS_ASC_FSTAT) & ASCFSTAT_TXFFLMASK;
return status ? 0 : TIOCSER_TEMT;
}
static unsigned int
ifxmipsasc_get_mctrl(struct uart_port *port)
{
return TIOCM_CTS | TIOCM_CAR | TIOCM_DSR;
}
static void
ifxmipsasc_set_mctrl(struct uart_port *port, u_int mctrl)
{
}
static void
ifxmipsasc_break_ctl(struct uart_port *port, int break_state)
{
}
static int
ifxmipsasc_startup(struct uart_port *port)
{
unsigned long flags;
int retval;
port->uartclk = ifxmips_get_fpi_hz();
ifxmips_w32(ifxmips_r32(port->membase + IFXMIPS_ASC_CLC) & ~IFXMIPS_ASC_CLC_DISS, port->membase + IFXMIPS_ASC_CLC);
ifxmips_w32(((ifxmips_r32(port->membase + IFXMIPS_ASC_CLC) & ~ASCCLC_RMCMASK)) | (1 << ASCCLC_RMCOFFSET), port->membase + IFXMIPS_ASC_CLC);
ifxmips_w32(0, port->membase + IFXMIPS_ASC_PISEL);
ifxmips_w32(((TXFIFO_FL << ASCTXFCON_TXFITLOFF) & ASCTXFCON_TXFITLMASK) | ASCTXFCON_TXFEN | ASCTXFCON_TXFFLU, port->membase + IFXMIPS_ASC_TXFCON);
ifxmips_w32(((RXFIFO_FL << ASCRXFCON_RXFITLOFF) & ASCRXFCON_RXFITLMASK) | ASCRXFCON_RXFEN | ASCRXFCON_RXFFLU, port->membase + IFXMIPS_ASC_RXFCON);
wmb ();
ifxmips_w32(ifxmips_r32(port->membase + IFXMIPS_ASC_CON) | ASCCON_M_8ASYNC | ASCCON_FEN | ASCCON_TOEN | ASCCON_ROEN, port->membase + IFXMIPS_ASC_CON);
local_irq_save(flags);
retval = request_irq(port->irq, ifxmipsasc_tx_int, IRQF_DISABLED, "asc_tx", port);
if(retval)
{
printk("failed to request ifxmipsasc_tx_int\n");
return retval;
}
retval = request_irq(port->irq + 2, ifxmipsasc_rx_int, IRQF_DISABLED, "asc_rx", port);
if(retval)
{
printk("failed to request ifxmipsasc_rx_int\n");
goto err1;
}
retval = request_irq(port->irq + 3, ifxmipsasc_er_int, IRQF_DISABLED, "asc_er", port);
if(retval)
{
printk("failed to request ifxmipsasc_er_int\n");
goto err2;
}
ifxmips_w32(ASC_IRNREN_RX_BUF | ASC_IRNREN_TX_BUF | ASC_IRNREN_ERR | ASC_IRNREN_TX, port->membase + IFXMIPS_ASC_IRNREN);
local_irq_restore(flags);
return 0;
err2:
free_irq(port->irq + 2, port);
err1:
free_irq(port->irq, port);
local_irq_restore(flags);
return retval;
}
static void
ifxmipsasc_shutdown(struct uart_port *port)
{
free_irq(port->irq, port);
free_irq(port->irq + 2, port);
free_irq(port->irq + 3, port);
ifxmips_w32(0, port->membase + IFXMIPS_ASC_CON);
ifxmips_w32(ifxmips_r32(port->membase + IFXMIPS_ASC_RXFCON) | ASCRXFCON_RXFFLU, port->membase + IFXMIPS_ASC_RXFCON);
ifxmips_w32(ifxmips_r32(port->membase + IFXMIPS_ASC_RXFCON) & ~ASCRXFCON_RXFEN, port->membase + IFXMIPS_ASC_RXFCON);
ifxmips_w32(ifxmips_r32(port->membase + IFXMIPS_ASC_TXFCON) | ASCTXFCON_TXFFLU, port->membase + IFXMIPS_ASC_TXFCON);
ifxmips_w32(ifxmips_r32(port->membase + IFXMIPS_ASC_TXFCON) & ~ASCTXFCON_TXFEN, port->membase + IFXMIPS_ASC_TXFCON);
}
static void ifxmipsasc_set_termios(struct uart_port *port, struct ktermios *new, struct ktermios *old)
{
unsigned int cflag;
unsigned int iflag;
unsigned int quot;
unsigned int baud;
unsigned int con = 0;
unsigned long flags;
cflag = new->c_cflag;
iflag = new->c_iflag;
switch(cflag & CSIZE)
{
case CS7:
con = ASCCON_M_7ASYNC;
break;
case CS5:
case CS6:
default:
con = ASCCON_M_8ASYNC;
break;
}
if(cflag & CSTOPB)
con |= ASCCON_STP;
if(cflag & PARENB)
{
if(!(cflag & PARODD))
con &= ~ASCCON_ODD;
else
con |= ASCCON_ODD;
}
port->read_status_mask = ASCSTATE_ROE;
if(iflag & INPCK)
port->read_status_mask |= ASCSTATE_FE | ASCSTATE_PE;
port->ignore_status_mask = 0;
if(iflag & IGNPAR)
port->ignore_status_mask |= ASCSTATE_FE | ASCSTATE_PE;
if(iflag & IGNBRK)
{
/*
* If we're ignoring parity and break indicators,
* ignore overruns too (for real raw support).
*/
if(iflag & IGNPAR)
port->ignore_status_mask |= ASCSTATE_ROE;
}
if((cflag & CREAD) == 0)
port->ignore_status_mask |= UART_DUMMY_UER_RX;
/* set error signals - framing, parity and overrun, enable receiver */
con |= ASCCON_FEN | ASCCON_TOEN | ASCCON_ROEN;
local_irq_save(flags);
/* set up CON */
ifxmips_w32(ifxmips_r32(port->membase + IFXMIPS_ASC_CON) | con, port->membase + IFXMIPS_ASC_CON);
/* Set baud rate - take a divider of 2 into account */
baud = uart_get_baud_rate(port, new, old, 0, port->uartclk / 16);
quot = uart_get_divisor(port, baud);
quot = quot / 2 - 1;
/* disable the baudrate generator */
ifxmips_w32(ifxmips_r32(port->membase + IFXMIPS_ASC_CON) & ~ASCCON_R, port->membase + IFXMIPS_ASC_CON);
/* make sure the fractional divider is off */
ifxmips_w32(ifxmips_r32(port->membase + IFXMIPS_ASC_CON) & ~ASCCON_FDE, port->membase + IFXMIPS_ASC_CON);
/* set up to use divisor of 2 */
ifxmips_w32(ifxmips_r32(port->membase + IFXMIPS_ASC_CON) & ~ASCCON_BRS, port->membase + IFXMIPS_ASC_CON);
/* now we can write the new baudrate into the register */
ifxmips_w32(quot, port->membase + IFXMIPS_ASC_BG);
/* turn the baudrate generator back on */
ifxmips_w32(ifxmips_r32(port->membase + IFXMIPS_ASC_CON) | ASCCON_R, port->membase + IFXMIPS_ASC_CON);
/* enable rx */
ifxmips_w32(ASCWHBSTATE_SETREN, port->membase + IFXMIPS_ASC_WHBSTATE);
local_irq_restore(flags);
}
static const char*
ifxmipsasc_type(struct uart_port *port)
{
if(port->type == PORT_IFXMIPSASC)
{
if(port->membase == (void*)IFXMIPS_ASC_BASE_ADDR)
return "asc0";
else
return "asc1";
} else {
return NULL;
}
}
static void
ifxmipsasc_release_port(struct uart_port *port)
{
}
static int
ifxmipsasc_request_port(struct uart_port *port)
{
return 0;
}
static void
ifxmipsasc_config_port(struct uart_port *port, int flags)
{
if(flags & UART_CONFIG_TYPE)
{
port->type = PORT_IFXMIPSASC;
ifxmipsasc_request_port(port);
}
}
static int
ifxmipsasc_verify_port(struct uart_port *port, struct serial_struct *ser)
{
int ret = 0;
if(ser->type != PORT_UNKNOWN && ser->type != PORT_IFXMIPSASC)
ret = -EINVAL;
if(ser->irq < 0 || ser->irq >= NR_IRQS)
ret = -EINVAL;
if(ser->baud_base < 9600)
ret = -EINVAL;
return ret;
}
static struct uart_ops ifxmipsasc_pops =
{
.tx_empty = ifxmipsasc_tx_empty,
.set_mctrl = ifxmipsasc_set_mctrl,
.get_mctrl = ifxmipsasc_get_mctrl,
.stop_tx = ifxmipsasc_stop_tx,
.start_tx = ifxmipsasc_start_tx,
.stop_rx = ifxmipsasc_stop_rx,
.enable_ms = ifxmipsasc_enable_ms,
.break_ctl = ifxmipsasc_break_ctl,
.startup = ifxmipsasc_startup,
.shutdown = ifxmipsasc_shutdown,
.set_termios = ifxmipsasc_set_termios,
.type = ifxmipsasc_type,
.release_port = ifxmipsasc_release_port,
.request_port = ifxmipsasc_request_port,
.config_port = ifxmipsasc_config_port,
.verify_port = ifxmipsasc_verify_port,
};
static struct uart_port ifxmipsasc_port[2] =
{
{
membase: (void *)IFXMIPS_ASC_BASE_ADDR,
mapbase: IFXMIPS_ASC_BASE_ADDR,
iotype: SERIAL_IO_MEM,
irq: IFXMIPSASC_TIR(0),
uartclk: 0,
fifosize: 16,
type: PORT_IFXMIPSASC,
ops: &ifxmipsasc_pops,
flags: ASYNC_BOOT_AUTOCONF,
line: 0
}, {
membase: (void *)(IFXMIPS_ASC_BASE_ADDR + IFXMIPS_ASC_BASE_DIFF),
mapbase: IFXMIPS_ASC_BASE_ADDR + IFXMIPS_ASC_BASE_DIFF,
iotype: SERIAL_IO_MEM,
irq: IFXMIPSASC_TIR(1),
uartclk: 0,
fifosize: 16,
type: PORT_IFXMIPSASC,
ops: &ifxmipsasc_pops,
flags: ASYNC_BOOT_AUTOCONF,
line: 1
}
};
static void
ifxmipsasc_console_write(struct console *co, const char *s, u_int count)
{
int port = co->index;
int i, fifocnt;
unsigned long flags;
local_irq_save(flags);
for(i = 0; i < count; i++)
{
do {
fifocnt = (ifxmips_r32((u32*)(IFXMIPS_ASC_BASE_ADDR + (port * IFXMIPS_ASC_BASE_DIFF) + IFXMIPS_ASC_FSTAT)) & ASCFSTAT_TXFFLMASK)
>> ASCFSTAT_TXFFLOFF;
} while(fifocnt == TXFIFO_FULL);
if(s[i] == '\0')
break;
if(s[i] == '\n')
{
ifxmips_w32('\r', (u32*)(IFXMIPS_ASC_BASE_ADDR + (port * IFXMIPS_ASC_BASE_DIFF) + IFXMIPS_ASC_TBUF));
do {
fifocnt = (ifxmips_r32((u32*)(IFXMIPS_ASC_BASE_ADDR + (port * IFXMIPS_ASC_BASE_DIFF) + IFXMIPS_ASC_FSTAT)) & ASCFSTAT_TXFFLMASK)
>> ASCFSTAT_TXFFLOFF;
} while(fifocnt == TXFIFO_FULL);
}
ifxmips_w32(s[i], (u32*)(IFXMIPS_ASC_BASE_ADDR + (port * IFXMIPS_ASC_BASE_DIFF) + IFXMIPS_ASC_TBUF));
}
local_irq_restore(flags);
}
static int __init
ifxmipsasc_console_setup(struct console *co, char *options)
{
int port = co->index;
int baud = 115200;
int bits = 8;
int parity = 'n';
int flow = 'n';
ifxmipsasc_port[port].uartclk = ifxmips_get_fpi_hz();
ifxmipsasc_port[port].type = PORT_IFXMIPSASC;
if(options)
uart_parse_options(options, &baud, &parity, &bits, &flow);
return uart_set_options(&ifxmipsasc_port[port], co, baud, parity, bits, flow);
}
static struct console ifxmipsasc_console[2] =
{
{
name: "ttyS",
write: ifxmipsasc_console_write,
device: uart_console_device,
setup: ifxmipsasc_console_setup,
flags: CON_PRINTBUFFER,
index: 0,
data: &ifxmipsasc_reg,
}, {
name: "ttyS",
write: ifxmipsasc_console_write,
device: uart_console_device,
setup: ifxmipsasc_console_setup,
flags: CON_PRINTBUFFER,
index: 1,
data: &ifxmipsasc_reg,
}
};
static int __init
ifxmipsasc_console_init(void)
{
register_console(&ifxmipsasc_console[0]);
register_console(&ifxmipsasc_console[1]);
return 0;
}
console_initcall(ifxmipsasc_console_init);
static struct uart_driver ifxmipsasc_reg =
{
.owner = THIS_MODULE,
.driver_name = "serial",
.dev_name = "ttyS",
.major = TTY_MAJOR,
.minor = 64,
.nr = 2,
.cons = &ifxmipsasc_console[1],
};
int __init
ifxmipsasc_init(void)
{
int ret;
uart_register_driver(&ifxmipsasc_reg);
ret = uart_add_one_port(&ifxmipsasc_reg, &ifxmipsasc_port[0]);
ret = uart_add_one_port(&ifxmipsasc_reg, &ifxmipsasc_port[1]);
return 0;
}
void __exit
ifxmipsasc_exit(void)
{
uart_unregister_driver(&ifxmipsasc_reg);
}
module_init(ifxmipsasc_init);
module_exit(ifxmipsasc_exit);
MODULE_AUTHOR("John Crispin <blogic@openwrt.org>");
MODULE_DESCRIPTION("MIPS IFXMips serial port driver");
MODULE_LICENSE("GPL");