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sh-sci.c
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/*
* drivers/serial/sh-sci.c
*
* SuperH on-chip serial module support. (SCI with no FIFO / with FIFO)
*
* Copyright (C) 2002, 2003, 2004 Paul Mundt
*
* based off of the old drivers/char/sh-sci.c by:
*
* Copyright (C) 1999, 2000 Niibe Yutaka
* Copyright (C) 2000 Sugioka Toshinobu
* Modified to support multiple serial ports. Stuart Menefy (May 2000).
* Modified to support SecureEdge. David McCullough (2002)
* Modified to support SH7300 SCIF. Takashi Kusuda (Jun 2003).
*
* 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.
*/
#undef DEBUG
#include <linux/config.h>
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/timer.h>
#include <linux/interrupt.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/serial.h>
#include <linux/major.h>
#include <linux/string.h>
#include <linux/sysrq.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/delay.h>
#include <linux/console.h>
#include <linux/bitops.h>
#ifdef CONFIG_CPU_FREQ
#include <linux/notifier.h>
#include <linux/cpufreq.h>
#endif
#include <asm/system.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/uaccess.h>
#include <linux/generic_serial.h>
#ifdef CONFIG_SH_STANDARD_BIOS
#include <asm/sh_bios.h>
#endif
#if defined(CONFIG_SERIAL_SH_SCI_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
#define SUPPORT_SYSRQ
#endif
#include "sh-sci.h"
#ifdef CONFIG_SH_KGDB
#include <asm/kgdb.h>
static int kgdb_get_char(struct sci_port *port);
static void kgdb_put_char(struct sci_port *port, char c);
static void kgdb_handle_error(struct sci_port *port);
static struct sci_port *kgdb_sci_port;
#endif /* CONFIG_SH_KGDB */
#ifdef CONFIG_SERIAL_SH_SCI_CONSOLE
static struct sci_port *serial_console_port = 0;
#endif /* CONFIG_SERIAL_SH_SCI_CONSOLE */
/* Function prototypes */
static void sci_stop_tx(struct uart_port *port);
static void sci_start_tx(struct uart_port *port);
static void sci_start_rx(struct uart_port *port, unsigned int tty_start);
static void sci_stop_rx(struct uart_port *port);
static int sci_request_irq(struct sci_port *port);
static void sci_free_irq(struct sci_port *port);
static struct sci_port sci_ports[SCI_NPORTS];
static struct uart_driver sci_uart_driver;
#if defined(CONFIG_SH_STANDARD_BIOS) || defined(CONFIG_SH_KGDB)
static void handle_error(struct uart_port *port)
{ /* Clear error flags */
sci_out(port, SCxSR, SCxSR_ERROR_CLEAR(port));
}
static int get_char(struct uart_port *port)
{
unsigned long flags;
unsigned short status;
int c;
local_irq_save(flags);
do {
status = sci_in(port, SCxSR);
if (status & SCxSR_ERRORS(port)) {
handle_error(port);
continue;
}
} while (!(status & SCxSR_RDxF(port)));
c = sci_in(port, SCxRDR);
sci_in(port, SCxSR); /* Dummy read */
sci_out(port, SCxSR, SCxSR_RDxF_CLEAR(port));
local_irq_restore(flags);
return c;
}
/* Taken from sh-stub.c of GDB 4.18 */
static const char hexchars[] = "0123456789abcdef";
static __inline__ char highhex(int x)
{
return hexchars[(x >> 4) & 0xf];
}
static __inline__ char lowhex(int x)
{
return hexchars[x & 0xf];
}
#endif /* CONFIG_SH_STANDARD_BIOS || CONFIG_SH_KGDB */
/*
* Send the packet in buffer. The host gets one chance to read it.
* This routine does not wait for a positive acknowledge.
*/
#ifdef CONFIG_SERIAL_SH_SCI_CONSOLE
static void put_char(struct uart_port *port, char c)
{
unsigned long flags;
unsigned short status;
local_irq_save(flags);
do {
status = sci_in(port, SCxSR);
} while (!(status & SCxSR_TDxE(port)));
sci_out(port, SCxTDR, c);
sci_in(port, SCxSR); /* Dummy read */
sci_out(port, SCxSR, SCxSR_TDxE_CLEAR(port));
local_irq_restore(flags);
}
static void put_string(struct sci_port *sci_port, const char *buffer, int count)
{
struct uart_port *port = &sci_port->port;
const unsigned char *p = buffer;
int i;
#if defined(CONFIG_SH_STANDARD_BIOS) || defined(CONFIG_SH_KGDB)
int checksum;
int usegdb=0;
#ifdef CONFIG_SH_STANDARD_BIOS
/* This call only does a trap the first time it is
* called, and so is safe to do here unconditionally
*/
usegdb |= sh_bios_in_gdb_mode();
#endif
#ifdef CONFIG_SH_KGDB
usegdb |= (kgdb_in_gdb_mode && (port == kgdb_sci_port));
#endif
if (usegdb) {
/* $<packet info>#<checksum>. */
do {
unsigned char c;
put_char(port, '$');
put_char(port, 'O'); /* 'O'utput to console */
checksum = 'O';
for (i=0; i<count; i++) { /* Don't use run length encoding */
int h, l;
c = *p++;
h = highhex(c);
l = lowhex(c);
put_char(port, h);
put_char(port, l);
checksum += h + l;
}
put_char(port, '#');
put_char(port, highhex(checksum));
put_char(port, lowhex(checksum));
} while (get_char(port) != '+');
} else
#endif /* CONFIG_SH_STANDARD_BIOS || CONFIG_SH_KGDB */
for (i=0; i<count; i++) {
if (*p == 10)
put_char(port, '\r');
put_char(port, *p++);
}
}
#endif /* CONFIG_SERIAL_SH_SCI_CONSOLE */
#ifdef CONFIG_SH_KGDB
/* Is the SCI ready, ie is there a char waiting? */
static int kgdb_is_char_ready(struct sci_port *port)
{
unsigned short status = sci_in(port, SCxSR);
if (status & (SCxSR_ERRORS(port) | SCxSR_BRK(port)))
kgdb_handle_error(port);
return (status & SCxSR_RDxF(port));
}
/* Write a char */
static void kgdb_put_char(struct sci_port *port, char c)
{
unsigned short status;
do
status = sci_in(port, SCxSR);
while (!(status & SCxSR_TDxE(port)));
sci_out(port, SCxTDR, c);
sci_in(port, SCxSR); /* Dummy read */
sci_out(port, SCxSR, SCxSR_TDxE_CLEAR(port));
}
/* Get a char if there is one, else ret -1 */
static int kgdb_get_char(struct sci_port *port)
{
int c;
if (kgdb_is_char_ready(port) == 0)
c = -1;
else {
c = sci_in(port, SCxRDR);
sci_in(port, SCxSR); /* Dummy read */
sci_out(port, SCxSR, SCxSR_RDxF_CLEAR(port));
}
return c;
}
/* Called from kgdbstub.c to get a character, i.e. is blocking */
static int kgdb_sci_getchar(void)
{
volatile int c;
/* Keep trying to read a character, this could be neater */
while ((c = kgdb_get_char(kgdb_sci_port)) < 0);
return c;
}
/* Called from kgdbstub.c to put a character, just a wrapper */
static void kgdb_sci_putchar(int c)
{
kgdb_put_char(kgdb_sci_port, c);
}
/* Clear any errors on the SCI */
static void kgdb_handle_error(struct sci_port *port)
{
sci_out(port, SCxSR, SCxSR_ERROR_CLEAR(port)); /* Clear error flags */
}
/* Breakpoint if there's a break sent on the serial port */
static void kgdb_break_interrupt(int irq, void *ptr, struct pt_regs *regs)
{
struct sci_port *port = ptr;
unsigned short status = sci_in(port, SCxSR);
if (status & SCxSR_BRK(port)) {
/* Break into the debugger if a break is detected */
BREAKPOINT();
/* Clear */
sci_out(port, SCxSR, SCxSR_BREAK_CLEAR(port));
}
}
#endif /* CONFIG_SH_KGDB */
#if defined(__H8300S__)
enum { sci_disable, sci_enable };
static void h8300_sci_enable(struct uart_port* port, unsigned int ctrl)
{
volatile unsigned char *mstpcrl=(volatile unsigned char *)MSTPCRL;
int ch = (port->mapbase - SMR0) >> 3;
unsigned char mask = 1 << (ch+1);
if (ctrl == sci_disable) {
*mstpcrl |= mask;
} else {
*mstpcrl &= ~mask;
}
}
#endif
#if defined(SCI_ONLY) || defined(SCI_AND_SCIF)
#if defined(__H8300H__) || defined(__H8300S__)
static void sci_init_pins_sci(struct uart_port* port, unsigned int cflag)
{
int ch = (port->mapbase - SMR0) >> 3;
/* set DDR regs */
H8300_GPIO_DDR(h8300_sci_pins[ch].port,h8300_sci_pins[ch].rx,H8300_GPIO_INPUT);
H8300_GPIO_DDR(h8300_sci_pins[ch].port,h8300_sci_pins[ch].tx,H8300_GPIO_OUTPUT);
/* tx mark output*/
H8300_SCI_DR(ch) |= h8300_sci_pins[ch].tx;
}
#else
static void sci_init_pins_sci(struct uart_port *port, unsigned int cflag)
{
}
#endif
#endif
#if defined(SCIF_ONLY) || defined(SCI_AND_SCIF)
#if defined(CONFIG_CPU_SH3)
/* For SH7705, SH7707, SH7709, SH7709A, SH7729, SH7300*/
static void sci_init_pins_scif(struct uart_port *port, unsigned int cflag)
{
unsigned int fcr_val = 0;
#if !defined(CONFIG_CPU_SUBTYPE_SH7300) /* SH7300 doesn't use RTS/CTS */
{
unsigned short data;
/* We need to set SCPCR to enable RTS/CTS */
data = ctrl_inw(SCPCR);
/* Clear out SCP7MD1,0, SCP6MD1,0, SCP4MD1,0*/
ctrl_outw(data&0x0fcf, SCPCR);
}
if (cflag & CRTSCTS)
fcr_val |= SCFCR_MCE;
else {
unsigned short data;
/* We need to set SCPCR to enable RTS/CTS */
data = ctrl_inw(SCPCR);
/* Clear out SCP7MD1,0, SCP4MD1,0,
Set SCP6MD1,0 = {01} (output) */
ctrl_outw((data&0x0fcf)|0x1000, SCPCR);
data = ctrl_inb(SCPDR);
/* Set /RTS2 (bit6) = 0 */
ctrl_outb(data&0xbf, SCPDR);
}
#endif
sci_out(port, SCFCR, fcr_val);
}
static void sci_init_pins_irda(struct uart_port *port, unsigned int cflag)
{
unsigned int fcr_val = 0;
if (cflag & CRTSCTS)
fcr_val |= SCFCR_MCE;
sci_out(port, SCFCR, fcr_val);
}
#else
/* For SH7750 */
static void sci_init_pins_scif(struct uart_port *port, unsigned int cflag)
{
unsigned int fcr_val = 0;
if (cflag & CRTSCTS) {
fcr_val |= SCFCR_MCE;
} else {
ctrl_outw(0x0080, SCSPTR2); /* Set RTS = 1 */
}
sci_out(port, SCFCR, fcr_val);
}
#endif
#endif /* SCIF_ONLY || SCI_AND_SCIF */
/* ********************************************************************** *
* the interrupt related routines *
* ********************************************************************** */
static void sci_transmit_chars(struct uart_port *port)
{
struct circ_buf *xmit = &port->info->xmit;
unsigned int stopped = uart_tx_stopped(port);
unsigned long flags;
unsigned short status;
unsigned short ctrl;
int count, txroom;
status = sci_in(port, SCxSR);
if (!(status & SCxSR_TDxE(port))) {
local_irq_save(flags);
ctrl = sci_in(port, SCSCR);
if (uart_circ_empty(xmit)) {
ctrl &= ~SCI_CTRL_FLAGS_TIE;
} else {
ctrl |= SCI_CTRL_FLAGS_TIE;
}
sci_out(port, SCSCR, ctrl);
local_irq_restore(flags);
return;
}
#if !defined(SCI_ONLY)
if (port->type == PORT_SCIF) {
txroom = SCIF_TXROOM_MAX - (sci_in(port, SCFDR)>>8);
} else {
txroom = (sci_in(port, SCxSR) & SCI_TDRE)?1:0;
}
#else
txroom = (sci_in(port, SCxSR) & SCI_TDRE)?1:0;
#endif
count = txroom;
do {
unsigned char c;
if (port->x_char) {
c = port->x_char;
port->x_char = 0;
} else if (!uart_circ_empty(xmit) && !stopped) {
c = xmit->buf[xmit->tail];
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
} else {
break;
}
sci_out(port, SCxTDR, c);
port->icount.tx++;
} while (--count > 0);
sci_out(port, SCxSR, SCxSR_TDxE_CLEAR(port));
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(port);
if (uart_circ_empty(xmit)) {
sci_stop_tx(port);
} else {
local_irq_save(flags);
ctrl = sci_in(port, SCSCR);
#if !defined(SCI_ONLY)
if (port->type == PORT_SCIF) {
sci_in(port, SCxSR); /* Dummy read */
sci_out(port, SCxSR, SCxSR_TDxE_CLEAR(port));
}
#endif
ctrl |= SCI_CTRL_FLAGS_TIE;
sci_out(port, SCSCR, ctrl);
local_irq_restore(flags);
}
}
/* On SH3, SCIF may read end-of-break as a space->mark char */
#define STEPFN(c) ({int __c=(c); (((__c-1)|(__c)) == -1); })
static inline void sci_receive_chars(struct uart_port *port,
struct pt_regs *regs)
{
struct tty_struct *tty = port->info->tty;
int i, count, copied = 0;
unsigned short status;
status = sci_in(port, SCxSR);
if (!(status & SCxSR_RDxF(port)))
return;
while (1) {
#if !defined(SCI_ONLY)
if (port->type == PORT_SCIF) {
count = sci_in(port, SCFDR)&SCIF_RFDC_MASK ;
} else {
count = (sci_in(port, SCxSR)&SCxSR_RDxF(port))?1:0;
}
#else
count = (sci_in(port, SCxSR)&SCxSR_RDxF(port))?1:0;
#endif
/* Don't copy more bytes than there is room for in the buffer */
if (tty->flip.count + count > TTY_FLIPBUF_SIZE)
count = TTY_FLIPBUF_SIZE - tty->flip.count;
/* If for any reason we can't copy more data, we're done! */
if (count == 0)
break;
if (port->type == PORT_SCI) {
char c = sci_in(port, SCxRDR);
if(((struct sci_port *)port)->break_flag
|| uart_handle_sysrq_char(port, c, regs)) {
count = 0;
} else {
tty->flip.char_buf_ptr[0] = c;
tty->flip.flag_buf_ptr[0] = TTY_NORMAL;
}
} else {
for (i=0; i<count; i++) {
char c = sci_in(port, SCxRDR);
status = sci_in(port, SCxSR);
#if defined(CONFIG_CPU_SH3)
/* Skip "chars" during break */
if (((struct sci_port *)port)->break_flag) {
if ((c == 0) &&
(status & SCxSR_FER(port))) {
count--; i--;
continue;
}
/* Nonzero => end-of-break */
pr_debug("scif: debounce<%02x>\n", c);
((struct sci_port *)port)->break_flag = 0;
if (STEPFN(c)) {
count--; i--;
continue;
}
}
#endif /* CONFIG_CPU_SH3 */
if (uart_handle_sysrq_char(port, c, regs)) {
count--; i--;
continue;
}
/* Store data and status */
tty->flip.char_buf_ptr[i] = c;
if (status&SCxSR_FER(port)) {
tty->flip.flag_buf_ptr[i] = TTY_FRAME;
pr_debug("sci: frame error\n");
} else if (status&SCxSR_PER(port)) {
tty->flip.flag_buf_ptr[i] = TTY_PARITY;
pr_debug("sci: parity error\n");
} else {
tty->flip.flag_buf_ptr[i] = TTY_NORMAL;
}
}
}
sci_in(port, SCxSR); /* dummy read */
sci_out(port, SCxSR, SCxSR_RDxF_CLEAR(port));
/* Update the kernel buffer end */
tty->flip.count += count;
tty->flip.char_buf_ptr += count;
tty->flip.flag_buf_ptr += count;
copied += count;
port->icount.rx += count;
}
if (copied) {
/* Tell the rest of the system the news. New characters! */
tty_flip_buffer_push(tty);
} else {
sci_in(port, SCxSR); /* dummy read */
sci_out(port, SCxSR, SCxSR_RDxF_CLEAR(port));
}
}
#define SCI_BREAK_JIFFIES (HZ/20)
/* The sci generates interrupts during the break,
* 1 per millisecond or so during the break period, for 9600 baud.
* So dont bother disabling interrupts.
* But dont want more than 1 break event.
* Use a kernel timer to periodically poll the rx line until
* the break is finished.
*/
static void sci_schedule_break_timer(struct sci_port *port)
{
port->break_timer.expires = jiffies + SCI_BREAK_JIFFIES;
add_timer(&port->break_timer);
}
/* Ensure that two consecutive samples find the break over. */
static void sci_break_timer(unsigned long data)
{
struct sci_port * port = (struct sci_port *)data;
if(sci_rxd_in(&port->port) == 0) {
port->break_flag = 1;
sci_schedule_break_timer(port);
} else if(port->break_flag == 1){
/* break is over. */
port->break_flag = 2;
sci_schedule_break_timer(port);
} else port->break_flag = 0;
}
static inline int sci_handle_errors(struct uart_port *port)
{
int copied = 0;
unsigned short status = sci_in(port, SCxSR);
struct tty_struct *tty = port->info->tty;
if (status&SCxSR_ORER(port) && tty->flip.count<TTY_FLIPBUF_SIZE) {
/* overrun error */
copied++;
*tty->flip.flag_buf_ptr++ = TTY_OVERRUN;
pr_debug("sci: overrun error\n");
}
if (status&SCxSR_FER(port) && tty->flip.count<TTY_FLIPBUF_SIZE) {
if (sci_rxd_in(port) == 0) {
/* Notify of BREAK */
struct sci_port * sci_port = (struct sci_port *)port;
if(!sci_port->break_flag) {
sci_port->break_flag = 1;
sci_schedule_break_timer((struct sci_port *)port);
/* Do sysrq handling. */
if(uart_handle_break(port)) {
return 0;
}
pr_debug("sci: BREAK detected\n");
copied++;
*tty->flip.flag_buf_ptr++ = TTY_BREAK;
}
}
else {
/* frame error */
copied++;
*tty->flip.flag_buf_ptr++ = TTY_FRAME;
pr_debug("sci: frame error\n");
}
}
if (status&SCxSR_PER(port) && tty->flip.count<TTY_FLIPBUF_SIZE) {
/* parity error */
copied++;
*tty->flip.flag_buf_ptr++ = TTY_PARITY;
pr_debug("sci: parity error\n");
}
if (copied) {
tty->flip.count += copied;
tty_flip_buffer_push(tty);
}
return copied;
}
static inline int sci_handle_breaks(struct uart_port *port)
{
int copied = 0;
unsigned short status = sci_in(port, SCxSR);
struct tty_struct *tty = port->info->tty;
struct sci_port *s = &sci_ports[port->line];
if (!s->break_flag && status & SCxSR_BRK(port) &&
tty->flip.count < TTY_FLIPBUF_SIZE) {
#if defined(CONFIG_CPU_SH3)
/* Debounce break */
s->break_flag = 1;
#endif
/* Notify of BREAK */
copied++;
*tty->flip.flag_buf_ptr++ = TTY_BREAK;
pr_debug("sci: BREAK detected\n");
}
#if defined(SCIF_ORER)
/* XXX: Handle SCIF overrun error */
if (port->type == PORT_SCIF && (sci_in(port, SCLSR) & SCIF_ORER) != 0) {
sci_out(port, SCLSR, 0);
if(tty->flip.count<TTY_FLIPBUF_SIZE) {
copied++;
*tty->flip.flag_buf_ptr++ = TTY_OVERRUN;
pr_debug("sci: overrun error\n");
}
}
#endif
if (copied) {
tty->flip.count += copied;
tty_flip_buffer_push(tty);
}
return copied;
}
static irqreturn_t sci_rx_interrupt(int irq, void *ptr, struct pt_regs *regs)
{
struct uart_port *port = ptr;
/* I think sci_receive_chars has to be called irrespective
* of whether the I_IXOFF is set, otherwise, how is the interrupt
* to be disabled?
*/
sci_receive_chars(port, regs);
return IRQ_HANDLED;
}
static irqreturn_t sci_tx_interrupt(int irq, void *ptr, struct pt_regs *regs)
{
struct uart_port *port = ptr;
sci_transmit_chars(port);
return IRQ_HANDLED;
}
static irqreturn_t sci_er_interrupt(int irq, void *ptr, struct pt_regs *regs)
{
struct uart_port *port = ptr;
/* Handle errors */
if (port->type == PORT_SCI) {
if (sci_handle_errors(port)) {
/* discard character in rx buffer */
sci_in(port, SCxSR);
sci_out(port, SCxSR, SCxSR_RDxF_CLEAR(port));
}
} else {
#if defined(SCIF_ORER)
if((sci_in(port, SCLSR) & SCIF_ORER) != 0) {
struct tty_struct *tty = port->info->tty;
sci_out(port, SCLSR, 0);
if(tty->flip.count<TTY_FLIPBUF_SIZE) {
*tty->flip.flag_buf_ptr++ = TTY_OVERRUN;
tty->flip.count++;
tty_flip_buffer_push(tty);
pr_debug("scif: overrun error\n");
}
}
#endif
sci_rx_interrupt(irq, ptr, regs);
}
sci_out(port, SCxSR, SCxSR_ERROR_CLEAR(port));
/* Kick the transmission */
sci_tx_interrupt(irq, ptr, regs);
return IRQ_HANDLED;
}
static irqreturn_t sci_br_interrupt(int irq, void *ptr, struct pt_regs *regs)
{
struct uart_port *port = ptr;
/* Handle BREAKs */
sci_handle_breaks(port);
sci_out(port, SCxSR, SCxSR_BREAK_CLEAR(port));
return IRQ_HANDLED;
}
static irqreturn_t sci_mpxed_interrupt(int irq, void *ptr, struct pt_regs *regs)
{
unsigned short ssr_status, scr_status;
struct uart_port *port = ptr;
ssr_status = sci_in(port,SCxSR);
scr_status = sci_in(port,SCSCR);
/* Tx Interrupt */
if ((ssr_status&0x0020) && (scr_status&0x0080))
sci_tx_interrupt(irq, ptr, regs);
/* Rx Interrupt */
if ((ssr_status&0x0002) && (scr_status&0x0040))
sci_rx_interrupt(irq, ptr, regs);
/* Error Interrupt */
if ((ssr_status&0x0080) && (scr_status&0x0400))
sci_er_interrupt(irq, ptr, regs);
/* Break Interrupt */
if ((ssr_status&0x0010) && (scr_status&0x0200))
sci_br_interrupt(irq, ptr, regs);
return IRQ_HANDLED;
}
#ifdef CONFIG_CPU_FREQ
/*
* Here we define a transistion notifier so that we can update all of our
* ports' baud rate when the peripheral clock changes.
*/
static int sci_notifier(struct notifier_block *self, unsigned long phase, void *p)
{
struct cpufreq_freqs *freqs = p;
int i;
if ((phase == CPUFREQ_POSTCHANGE) ||
(phase == CPUFREQ_RESUMECHANGE)){
for (i = 0; i < SCI_NPORTS; i++) {
struct uart_port *port = &sci_ports[i].port;
/*
* Update the uartclk per-port if frequency has
* changed, since it will no longer necessarily be
* consistent with the old frequency.
*
* Really we want to be able to do something like
* uart_change_speed() or something along those lines
* here to implicitly reset the per-port baud rate..
*
* Clean this up later..
*/
port->uartclk = current_cpu_data.module_clock * 16;
}
printk("%s: got a postchange notification for cpu %d (old %d, new %d)\n",
__FUNCTION__, freqs->cpu, freqs->old, freqs->new);
}
return NOTIFY_OK;
}
static struct notifier_block sci_nb = { &sci_notifier, NULL, 0 };
#endif /* CONFIG_CPU_FREQ */
static int sci_request_irq(struct sci_port *port)
{
int i;
irqreturn_t (*handlers[4])(int irq, void *ptr, struct pt_regs *regs) = {
sci_er_interrupt, sci_rx_interrupt, sci_tx_interrupt,
sci_br_interrupt,
};
const char *desc[] = { "SCI Receive Error", "SCI Receive Data Full",
"SCI Transmit Data Empty", "SCI Break" };
if (port->irqs[0] == port->irqs[1]) {
if (!port->irqs[0]) {
printk(KERN_ERR "sci: Cannot allocate irq.(IRQ=0)\n");
return -ENODEV;
}
if (request_irq(port->irqs[0], sci_mpxed_interrupt, SA_INTERRUPT,
"sci", port)) {
printk(KERN_ERR "sci: Cannot allocate irq.\n");
return -ENODEV;
}
} else {
for (i = 0; i < ARRAY_SIZE(handlers); i++) {
if (!port->irqs[i])
continue;
if (request_irq(port->irqs[i], handlers[i], SA_INTERRUPT,
desc[i], port)) {
printk(KERN_ERR "sci: Cannot allocate irq.\n");
return -ENODEV;
}
}
}
return 0;
}
static void sci_free_irq(struct sci_port *port)
{
int i;
if (port->irqs[0] == port->irqs[1]) {
if (!port->irqs[0])
printk("sci: sci_free_irq error\n");
else
free_irq(port->irqs[0], port);
} else {
for (i = 0; i < ARRAY_SIZE(port->irqs); i++) {
if (!port->irqs[i])
continue;
free_irq(port->irqs[i], port);
}
}
}
static unsigned int sci_tx_empty(struct uart_port *port)
{
/* Can't detect */
return TIOCSER_TEMT;
}
static void sci_set_mctrl(struct uart_port *port, unsigned int mctrl)
{
/* This routine is used for seting signals of: DTR, DCD, CTS/RTS */
/* We use SCIF's hardware for CTS/RTS, so don't need any for that. */
/* If you have signals for DTR and DCD, please implement here. */
}
static unsigned int sci_get_mctrl(struct uart_port *port)
{
/* This routine is used for geting signals of: DTR, DCD, DSR, RI,
and CTS/RTS */
return TIOCM_DTR | TIOCM_RTS | TIOCM_DSR;
}
static void sci_start_tx(struct uart_port *port)
{
struct sci_port *s = &sci_ports[port->line];
disable_irq(s->irqs[SCIx_TXI_IRQ]);
sci_transmit_chars(port);
enable_irq(s->irqs[SCIx_TXI_IRQ]);
}
static void sci_stop_tx(struct uart_port *port)
{
unsigned long flags;
unsigned short ctrl;
/* Clear TIE (Transmit Interrupt Enable) bit in SCSCR */
local_irq_save(flags);
ctrl = sci_in(port, SCSCR);
ctrl &= ~SCI_CTRL_FLAGS_TIE;
sci_out(port, SCSCR, ctrl);
local_irq_restore(flags);
}
static void sci_start_rx(struct uart_port *port, unsigned int tty_start)
{
unsigned long flags;
unsigned short ctrl;
/* Set RIE (Receive Interrupt Enable) bit in SCSCR */
local_irq_save(flags);
ctrl = sci_in(port, SCSCR);
ctrl |= SCI_CTRL_FLAGS_RIE | SCI_CTRL_FLAGS_REIE;
sci_out(port, SCSCR, ctrl);
local_irq_restore(flags);
}
static void sci_stop_rx(struct uart_port *port)
{
unsigned long flags;
unsigned short ctrl;
/* Clear RIE (Receive Interrupt Enable) bit in SCSCR */
local_irq_save(flags);
ctrl = sci_in(port, SCSCR);
ctrl &= ~(SCI_CTRL_FLAGS_RIE | SCI_CTRL_FLAGS_REIE);
sci_out(port, SCSCR, ctrl);
local_irq_restore(flags);
}
static void sci_enable_ms(struct uart_port *port)
{
/* Nothing here yet .. */
}
static void sci_break_ctl(struct uart_port *port, int break_state)
{
/* Nothing here yet .. */
}
static int sci_startup(struct uart_port *port)
{
struct sci_port *s = &sci_ports[port->line];
#if defined(__H8300S__)
h8300_sci_enable(port, sci_enable);
#endif
sci_request_irq(s);
sci_start_tx(port, 1);
sci_start_rx(port, 1);
return 0;
}
static void sci_shutdown(struct uart_port *port)
{
struct sci_port *s = &sci_ports[port->line];
sci_stop_rx(port);
sci_stop_tx(port);
sci_free_irq(s);
#if defined(__H8300S__)
h8300_sci_enable(port, sci_disable);
#endif
}
static void sci_set_termios(struct uart_port *port, struct termios *termios,
struct termios *old)
{
struct sci_port *s = &sci_ports[port->line];
unsigned int status, baud, smr_val;
unsigned long flags;
int t;
baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
spin_lock_irqsave(&port->lock, flags);