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sh-sci.c
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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 - 2006 Paul Mundt
* Modified to support SH7720 SCIF. Markus Brunner, Mark Jonas (Jul 2007).
*
* 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).
* Removed SH7300 support (Jul 2007).
*
* 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.
*/
#if defined(CONFIG_SERIAL_SH_SCI_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
#define SUPPORT_SYSRQ
#endif
#undef DEBUG
#include <linux/module.h>
#include <linux/errno.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/ioport.h>
#include <linux/mm.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/console.h>
#include <linux/platform_device.h>
#include <linux/serial_sci.h>
#include <linux/notifier.h>
#include <linux/cpufreq.h>
#include <linux/clk.h>
#include <linux/ctype.h>
#ifdef CONFIG_SUPERH
#include <asm/clock.h>
#include <asm/sh_bios.h>
#include <asm/kgdb.h>
#endif
#include "sh-sci.h"
struct sci_port {
struct uart_port port;
/* Port type */
unsigned int type;
/* Port IRQs: ERI, RXI, TXI, BRI (optional) */
unsigned int irqs[SCIx_NR_IRQS];
/* Port pin configuration */
void (*init_pins)(struct uart_port *port,
unsigned int cflag);
/* Port enable callback */
void (*enable)(struct uart_port *port);
/* Port disable callback */
void (*disable)(struct uart_port *port);
/* Break timer */
struct timer_list break_timer;
int break_flag;
#ifdef CONFIG_SUPERH
/* Port clock */
struct clk *clk;
#endif
};
#ifdef CONFIG_SH_KGDB
static struct sci_port *kgdb_sci_port;
#endif
#ifdef CONFIG_SERIAL_SH_SCI_CONSOLE
static struct sci_port *serial_console_port;
#endif
/* Function prototypes */
static void sci_stop_tx(struct uart_port *port);
#define SCI_NPORTS CONFIG_SERIAL_SH_SCI_NR_UARTS
static struct sci_port sci_ports[SCI_NPORTS];
static struct uart_driver sci_uart_driver;
#if defined(CONFIG_SERIAL_SH_SCI_CONSOLE) && \
defined(CONFIG_SH_STANDARD_BIOS) || defined(CONFIG_SH_KGDB)
static inline 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;
spin_lock_irqsave(&port->lock, 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));
spin_unlock_irqrestore(&port->lock, flags);
return c;
}
#endif /* CONFIG_SH_STANDARD_BIOS || CONFIG_SH_KGDB */
#if defined(CONFIG_SERIAL_SH_SCI_CONSOLE) || defined(CONFIG_SH_KGDB)
static void put_char(struct uart_port *port, char c)
{
unsigned long flags;
unsigned short status;
spin_lock_irqsave(&port->lock, 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));
spin_unlock_irqrestore(&port->lock, flags);
}
#endif
#ifdef CONFIG_SERIAL_SH_SCI_CONSOLE
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 && (sci_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 = hex_asc_hi(c);
l = hex_asc_lo(c);
put_char(port, h);
put_char(port, l);
checksum += h + l;
}
put_char(port, '#');
put_char(port, hex_asc_hi(checksum));
put_char(port, hex_asc_lo(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
static int kgdb_sci_getchar(void)
{
int c;
/* Keep trying to read a character, this could be neater */
while ((c = get_char(&kgdb_sci_port->port)) < 0)
cpu_relax();
return c;
}
static inline void kgdb_sci_putchar(int c)
{
put_char(&kgdb_sci_port->port, c);
}
#endif /* CONFIG_SH_KGDB */
#if defined(__H8300S__)
enum { sci_disable, sci_enable };
static void h8300_sci_config(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;
}
}
static inline void h8300_sci_enable(struct uart_port *port)
{
h8300_sci_config(port, sci_enable);
}
static inline void h8300_sci_disable(struct uart_port *port)
{
h8300_sci_config(port, sci_disable);
}
#endif
#if defined(SCI_ONLY) || defined(SCI_AND_SCIF) && \
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
#define sci_init_pins_sci NULL
#endif
#if defined(CONFIG_CPU_SUBTYPE_SH7707) || defined(CONFIG_CPU_SUBTYPE_SH7709)
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
#define sci_init_pins_irda NULL
#endif
#ifdef SCI_ONLY
#define sci_init_pins_scif NULL
#endif
#if defined(SCIF_ONLY) || defined(SCI_AND_SCIF)
#if defined(CONFIG_CPU_SUBTYPE_SH7710) || defined(CONFIG_CPU_SUBTYPE_SH7712)
static void sci_init_pins_scif(struct uart_port* port, unsigned int cflag)
{
unsigned int fcr_val = 0;
set_sh771x_scif_pfc(port);
if (cflag & CRTSCTS) {
fcr_val |= SCFCR_MCE;
}
sci_out(port, SCFCR, fcr_val);
}
#elif defined(CONFIG_CPU_SUBTYPE_SH7720) || defined(CONFIG_CPU_SUBTYPE_SH7721)
static void sci_init_pins_scif(struct uart_port *port, unsigned int cflag)
{
unsigned int fcr_val = 0;
unsigned short data;
if (cflag & CRTSCTS) {
/* enable RTS/CTS */
if (port->mapbase == 0xa4430000) { /* SCIF0 */
/* Clear PTCR bit 9-2; enable all scif pins but sck */
data = ctrl_inw(PORT_PTCR);
ctrl_outw((data & 0xfc03), PORT_PTCR);
} else if (port->mapbase == 0xa4438000) { /* SCIF1 */
/* Clear PVCR bit 9-2 */
data = ctrl_inw(PORT_PVCR);
ctrl_outw((data & 0xfc03), PORT_PVCR);
}
fcr_val |= SCFCR_MCE;
} else {
if (port->mapbase == 0xa4430000) { /* SCIF0 */
/* Clear PTCR bit 5-2; enable only tx and rx */
data = ctrl_inw(PORT_PTCR);
ctrl_outw((data & 0xffc3), PORT_PTCR);
} else if (port->mapbase == 0xa4438000) { /* SCIF1 */
/* Clear PVCR bit 5-2 */
data = ctrl_inw(PORT_PVCR);
ctrl_outw((data & 0xffc3), PORT_PVCR);
}
}
sci_out(port, SCFCR, fcr_val);
}
#elif defined(CONFIG_CPU_SH3)
/* For SH7705, SH7706, SH7707, SH7709, SH7709A, SH7729 */
static void sci_init_pins_scif(struct uart_port *port, unsigned int cflag)
{
unsigned int fcr_val = 0;
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 {
/* 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);
}
sci_out(port, SCFCR, fcr_val);
}
#elif defined(CONFIG_CPU_SUBTYPE_SH7722)
static void sci_init_pins_scif(struct uart_port *port, unsigned int cflag)
{
unsigned int fcr_val = 0;
unsigned short data;
if (port->mapbase == 0xffe00000) {
data = ctrl_inw(PSCR);
data &= ~0x03cf;
if (cflag & CRTSCTS)
fcr_val |= SCFCR_MCE;
else
data |= 0x0340;
ctrl_outw(data, PSCR);
}
/* SCIF1 and SCIF2 should be setup by board code */
sci_out(port, SCFCR, fcr_val);
}
#elif defined(CONFIG_CPU_SUBTYPE_SH7723)
static void sci_init_pins_scif(struct uart_port *port, unsigned int cflag)
{
/* Nothing to do here.. */
sci_out(port, SCFCR, 0);
}
#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 {
#if defined(CONFIG_CPU_SUBTYPE_SH7343) || defined(CONFIG_CPU_SUBTYPE_SH7366)
/* Nothing */
#elif defined(CONFIG_CPU_SUBTYPE_SH7763) || \
defined(CONFIG_CPU_SUBTYPE_SH7780) || \
defined(CONFIG_CPU_SUBTYPE_SH7785) || \
defined(CONFIG_CPU_SUBTYPE_SHX3)
ctrl_outw(0x0080, SCSPTR0); /* Set RTS = 1 */
#else
ctrl_outw(0x0080, SCSPTR2); /* Set RTS = 1 */
#endif
}
sci_out(port, SCFCR, fcr_val);
}
#endif
#if defined(CONFIG_CPU_SUBTYPE_SH7760) || \
defined(CONFIG_CPU_SUBTYPE_SH7780) || \
defined(CONFIG_CPU_SUBTYPE_SH7785)
static inline int scif_txroom(struct uart_port *port)
{
return SCIF_TXROOM_MAX - (sci_in(port, SCTFDR) & 0xff);
}
static inline int scif_rxroom(struct uart_port *port)
{
return sci_in(port, SCRFDR) & 0xff;
}
#elif defined(CONFIG_CPU_SUBTYPE_SH7763)
static inline int scif_txroom(struct uart_port *port)
{
if((port->mapbase == 0xffe00000) || (port->mapbase == 0xffe08000)) /* SCIF0/1*/
return SCIF_TXROOM_MAX - (sci_in(port, SCTFDR) & 0xff);
else /* SCIF2 */
return SCIF2_TXROOM_MAX - (sci_in(port, SCFDR) >> 8);
}
static inline int scif_rxroom(struct uart_port *port)
{
if((port->mapbase == 0xffe00000) || (port->mapbase == 0xffe08000)) /* SCIF0/1*/
return sci_in(port, SCRFDR) & 0xff;
else /* SCIF2 */
return sci_in(port, SCFDR) & SCIF2_RFDC_MASK;
}
#else
static inline int scif_txroom(struct uart_port *port)
{
return SCIF_TXROOM_MAX - (sci_in(port, SCFDR) >> 8);
}
static inline int scif_rxroom(struct uart_port *port)
{
return sci_in(port, SCFDR) & SCIF_RFDC_MASK;
}
#endif
#endif /* SCIF_ONLY || SCI_AND_SCIF */
static inline int sci_txroom(struct uart_port *port)
{
return ((sci_in(port, SCxSR) & SCI_TDRE) != 0);
}
static inline int sci_rxroom(struct uart_port *port)
{
return ((sci_in(port, SCxSR) & SCxSR_RDxF(port)) != 0);
}
/* ********************************************************************** *
* 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 short status;
unsigned short ctrl;
int count;
status = sci_in(port, SCxSR);
if (!(status & SCxSR_TDxE(port))) {
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);
return;
}
#ifndef SCI_ONLY
if (port->type == PORT_SCIF)
count = scif_txroom(port);
else
#endif
count = sci_txroom(port);
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 {
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);
}
}
/* 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 sci_port *sci_port = (struct sci_port *)port;
struct tty_struct *tty = port->info->port.tty;
int i, count, copied = 0;
unsigned short status;
unsigned char flag;
status = sci_in(port, SCxSR);
if (!(status & SCxSR_RDxF(port)))
return;
while (1) {
#if !defined(SCI_ONLY)
if (port->type == PORT_SCIF)
count = scif_rxroom(port);
else
#endif
count = sci_rxroom(port);
/* Don't copy more bytes than there is room for in the buffer */
count = tty_buffer_request_room(tty, 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 (uart_handle_sysrq_char(port, c) || sci_port->break_flag)
count = 0;
else {
tty_insert_flip_char(tty, c, 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 (sci_port->break_flag) {
if ((c == 0) &&
(status & SCxSR_FER(port))) {
count--; i--;
continue;
}
/* Nonzero => end-of-break */
pr_debug("scif: debounce<%02x>\n", c);
sci_port->break_flag = 0;
if (STEPFN(c)) {
count--; i--;
continue;
}
}
#endif /* CONFIG_CPU_SH3 */
if (uart_handle_sysrq_char(port, c)) {
count--; i--;
continue;
}
/* Store data and status */
if (status&SCxSR_FER(port)) {
flag = TTY_FRAME;
pr_debug("sci: frame error\n");
} else if (status&SCxSR_PER(port)) {
flag = TTY_PARITY;
pr_debug("sci: parity error\n");
} else
flag = TTY_NORMAL;
tty_insert_flip_char(tty, c, flag);
}
}
sci_in(port, SCxSR); /* dummy read */
sci_out(port, SCxSR, SCxSR_RDxF_CLEAR(port));
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->port.tty;
if (status & SCxSR_ORER(port)) {
/* overrun error */
if (tty_insert_flip_char(tty, 0, TTY_OVERRUN))
copied++;
pr_debug("sci: overrun error\n");
}
if (status & SCxSR_FER(port)) {
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(sci_port);
/* Do sysrq handling. */
if (uart_handle_break(port))
return 0;
pr_debug("sci: BREAK detected\n");
if (tty_insert_flip_char(tty, 0, TTY_BREAK))
copied++;
}
} else {
/* frame error */
if (tty_insert_flip_char(tty, 0, TTY_FRAME))
copied++;
pr_debug("sci: frame error\n");
}
}
if (status & SCxSR_PER(port)) {
/* parity error */
if (tty_insert_flip_char(tty, 0, TTY_PARITY))
copied++;
pr_debug("sci: parity error\n");
}
if (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->port.tty;
struct sci_port *s = &sci_ports[port->line];
if (uart_handle_break(port))
return 0;
if (!s->break_flag && status & SCxSR_BRK(port)) {
#if defined(CONFIG_CPU_SH3)
/* Debounce break */
s->break_flag = 1;
#endif
/* Notify of BREAK */
if (tty_insert_flip_char(tty, 0, TTY_BREAK))
copied++;
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_insert_flip_char(tty, 0, TTY_OVERRUN)) {
copied++;
pr_debug("sci: overrun error\n");
}
}
#endif
if (copied)
tty_flip_buffer_push(tty);
return copied;
}
static irqreturn_t sci_rx_interrupt(int irq, void *port)
{
/* 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);
return IRQ_HANDLED;
}
static irqreturn_t sci_tx_interrupt(int irq, void *ptr)
{
struct uart_port *port = ptr;
spin_lock_irq(&port->lock);
sci_transmit_chars(port);
spin_unlock_irq(&port->lock);
return IRQ_HANDLED;
}
static irqreturn_t sci_er_interrupt(int irq, void *ptr)
{
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->port.tty;
sci_out(port, SCLSR, 0);
tty_insert_flip_char(tty, 0, TTY_OVERRUN);
tty_flip_buffer_push(tty);
pr_debug("scif: overrun error\n");
}
#endif
sci_rx_interrupt(irq, ptr);
}
sci_out(port, SCxSR, SCxSR_ERROR_CLEAR(port));
/* Kick the transmission */
sci_tx_interrupt(irq, ptr);
return IRQ_HANDLED;
}
static irqreturn_t sci_br_interrupt(int irq, void *ptr)
{
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)
{
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);
/* Rx Interrupt */
if ((ssr_status & 0x0002) && (scr_status & 0x0040))
sci_rx_interrupt(irq, ptr);
/* Error Interrupt */
if ((ssr_status & 0x0080) && (scr_status & 0x0400))
sci_er_interrupt(irq, ptr);
/* Break Interrupt */
if ((ssr_status & 0x0010) && (scr_status & 0x0200))
sci_br_interrupt(irq, ptr);
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;
struct clk *clk;
/*
* 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..
*/
clk = clk_get(NULL, "module_clk");
port->uartclk = clk_get_rate(clk) * 16;
clk_put(clk);
}
printk(KERN_INFO "%s: got a postchange notification "
"for cpu %d (old %d, new %d)\n",
__func__, 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) = {
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,
IRQF_DISABLED, "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],
IRQF_DISABLED, 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)
{
unsigned short ctrl;
/* Set TIE (Transmit Interrupt Enable) bit in SCSCR */
ctrl = sci_in(port, SCSCR);
ctrl |= SCI_CTRL_FLAGS_TIE;
sci_out(port, SCSCR, ctrl);
}
static void sci_stop_tx(struct uart_port *port)
{
unsigned short ctrl;
/* Clear TIE (Transmit Interrupt Enable) bit in SCSCR */
ctrl = sci_in(port, SCSCR);
ctrl &= ~SCI_CTRL_FLAGS_TIE;
sci_out(port, SCSCR, ctrl);
}
static void sci_start_rx(struct uart_port *port, unsigned int tty_start)
{
unsigned short ctrl;
/* Set RIE (Receive Interrupt Enable) bit in SCSCR */
ctrl = sci_in(port, SCSCR);
ctrl |= SCI_CTRL_FLAGS_RIE | SCI_CTRL_FLAGS_REIE;
sci_out(port, SCSCR, ctrl);
}
static void sci_stop_rx(struct uart_port *port)
{
unsigned short ctrl;
/* Clear RIE (Receive Interrupt Enable) bit in SCSCR */
ctrl = sci_in(port, SCSCR);
ctrl &= ~(SCI_CTRL_FLAGS_RIE | SCI_CTRL_FLAGS_REIE);
sci_out(port, SCSCR, ctrl);
}
static void sci_enable_ms(struct uart_port *port)
{
/* Nothing here yet .. */
}
static void sci_break_ctl(struct uart_port *port, int break_state)
{