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linux/drivers/char/vme_scc.c
Alan Cox 9e98966c7b tty: rework break handling 
Some hardware needs to do break handling itself and may have partial
support only. Make break_ctl return an error code. Add a tty driver flag
so you can indicate driver hardware side break support.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-22 13:03:28 -07:00

1035 lines
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/*
* drivers/char/vme_scc.c: MVME147, MVME162, BVME6000 SCC serial ports
* implementation.
* Copyright 1999 Richard Hirst <richard@sleepie.demon.co.uk>
*
* Based on atari_SCC.c which was
* Copyright 1994-95 Roman Hodek <Roman.Hodek@informatik.uni-erlangen.de>
* Partially based on PC-Linux serial.c by Linus Torvalds and Theodore Ts'o
*
* 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.
*
*/
#include <linux/module.h>
#include <linux/kdev_t.h>
#include <asm/io.h>
#include <linux/kernel.h>
#include <linux/ioport.h>
#include <linux/interrupt.h>
#include <linux/errno.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/mm.h>
#include <linux/serial.h>
#include <linux/fcntl.h>
#include <linux/major.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/miscdevice.h>
#include <linux/console.h>
#include <linux/init.h>
#include <asm/setup.h>
#include <asm/bootinfo.h>
#ifdef CONFIG_MVME147_SCC
#include <asm/mvme147hw.h>
#endif
#ifdef CONFIG_MVME162_SCC
#include <asm/mvme16xhw.h>
#endif
#ifdef CONFIG_BVME6000_SCC
#include <asm/bvme6000hw.h>
#endif
#include <linux/generic_serial.h>
#include "scc.h"
#define CHANNEL_A 0
#define CHANNEL_B 1
#define SCC_MINOR_BASE 64
/* Shadows for all SCC write registers */
static unsigned char scc_shadow[2][16];
/* Location to access for SCC register access delay */
static volatile unsigned char *scc_del = NULL;
/* To keep track of STATUS_REG state for detection of Ext/Status int source */
static unsigned char scc_last_status_reg[2];
/***************************** Prototypes *****************************/
/* Function prototypes */
static void scc_disable_tx_interrupts(void * ptr);
static void scc_enable_tx_interrupts(void * ptr);
static void scc_disable_rx_interrupts(void * ptr);
static void scc_enable_rx_interrupts(void * ptr);
static int scc_get_CD(void * ptr);
static void scc_shutdown_port(void * ptr);
static int scc_set_real_termios(void *ptr);
static void scc_hungup(void *ptr);
static void scc_close(void *ptr);
static int scc_chars_in_buffer(void * ptr);
static int scc_open(struct tty_struct * tty, struct file * filp);
static int scc_ioctl(struct tty_struct * tty, struct file * filp,
unsigned int cmd, unsigned long arg);
static void scc_throttle(struct tty_struct *tty);
static void scc_unthrottle(struct tty_struct *tty);
static irqreturn_t scc_tx_int(int irq, void *data);
static irqreturn_t scc_rx_int(int irq, void *data);
static irqreturn_t scc_stat_int(int irq, void *data);
static irqreturn_t scc_spcond_int(int irq, void *data);
static void scc_setsignals(struct scc_port *port, int dtr, int rts);
static int scc_break_ctl(struct tty_struct *tty, int break_state);
static struct tty_driver *scc_driver;
static struct scc_port scc_ports[2];
/*---------------------------------------------------------------------------
* Interface from generic_serial.c back here
*--------------------------------------------------------------------------*/
static struct real_driver scc_real_driver = {
scc_disable_tx_interrupts,
scc_enable_tx_interrupts,
scc_disable_rx_interrupts,
scc_enable_rx_interrupts,
scc_get_CD,
scc_shutdown_port,
scc_set_real_termios,
scc_chars_in_buffer,
scc_close,
scc_hungup,
NULL
};
static const struct tty_operations scc_ops = {
.open = scc_open,
.close = gs_close,
.write = gs_write,
.put_char = gs_put_char,
.flush_chars = gs_flush_chars,
.write_room = gs_write_room,
.chars_in_buffer = gs_chars_in_buffer,
.flush_buffer = gs_flush_buffer,
.ioctl = scc_ioctl,
.throttle = scc_throttle,
.unthrottle = scc_unthrottle,
.set_termios = gs_set_termios,
.stop = gs_stop,
.start = gs_start,
.hangup = gs_hangup,
.break_ctl = scc_break_ctl,
};
/*----------------------------------------------------------------------------
* vme_scc_init() and support functions
*---------------------------------------------------------------------------*/
static int scc_init_drivers(void)
{
int error;
scc_driver = alloc_tty_driver(2);
if (!scc_driver)
return -ENOMEM;
scc_driver->owner = THIS_MODULE;
scc_driver->driver_name = "scc";
scc_driver->name = "ttyS";
scc_driver->major = TTY_MAJOR;
scc_driver->minor_start = SCC_MINOR_BASE;
scc_driver->type = TTY_DRIVER_TYPE_SERIAL;
scc_driver->subtype = SERIAL_TYPE_NORMAL;
scc_driver->init_termios = tty_std_termios;
scc_driver->init_termios.c_cflag =
B9600 | CS8 | CREAD | HUPCL | CLOCAL;
scc_driver->init_termios.c_ispeed = 9600;
scc_driver->init_termios.c_ospeed = 9600;
scc_driver->flags = TTY_DRIVER_REAL_RAW;
tty_set_operations(scc_driver, &scc_ops);
if ((error = tty_register_driver(scc_driver))) {
printk(KERN_ERR "scc: Couldn't register scc driver, error = %d\n",
error);
put_tty_driver(scc_driver);
return 1;
}
return 0;
}
/* ports[] array is indexed by line no (i.e. [0] for ttyS0, [1] for ttyS1).
*/
static void scc_init_portstructs(void)
{
struct scc_port *port;
int i;
for (i = 0; i < 2; i++) {
port = scc_ports + i;
port->gs.magic = SCC_MAGIC;
port->gs.close_delay = HZ/2;
port->gs.closing_wait = 30 * HZ;
port->gs.rd = &scc_real_driver;
#ifdef NEW_WRITE_LOCKING
port->gs.port_write_mutex = MUTEX;
#endif
init_waitqueue_head(&port->gs.open_wait);
init_waitqueue_head(&port->gs.close_wait);
}
}
#ifdef CONFIG_MVME147_SCC
static int mvme147_scc_init(void)
{
struct scc_port *port;
printk(KERN_INFO "SCC: MVME147 Serial Driver\n");
/* Init channel A */
port = &scc_ports[0];
port->channel = CHANNEL_A;
port->ctrlp = (volatile unsigned char *)M147_SCC_A_ADDR;
port->datap = port->ctrlp + 1;
port->port_a = &scc_ports[0];
port->port_b = &scc_ports[1];
request_irq(MVME147_IRQ_SCCA_TX, scc_tx_int, IRQF_DISABLED,
"SCC-A TX", port);
request_irq(MVME147_IRQ_SCCA_STAT, scc_stat_int, IRQF_DISABLED,
"SCC-A status", port);
request_irq(MVME147_IRQ_SCCA_RX, scc_rx_int, IRQF_DISABLED,
"SCC-A RX", port);
request_irq(MVME147_IRQ_SCCA_SPCOND, scc_spcond_int, IRQF_DISABLED,
"SCC-A special cond", port);
{
SCC_ACCESS_INIT(port);
/* disable interrupts for this channel */
SCCwrite(INT_AND_DMA_REG, 0);
/* Set the interrupt vector */
SCCwrite(INT_VECTOR_REG, MVME147_IRQ_SCC_BASE);
/* Interrupt parameters: vector includes status, status low */
SCCwrite(MASTER_INT_CTRL, MIC_VEC_INCL_STAT);
SCCmod(MASTER_INT_CTRL, 0xff, MIC_MASTER_INT_ENAB);
}
/* Init channel B */
port = &scc_ports[1];
port->channel = CHANNEL_B;
port->ctrlp = (volatile unsigned char *)M147_SCC_B_ADDR;
port->datap = port->ctrlp + 1;
port->port_a = &scc_ports[0];
port->port_b = &scc_ports[1];
request_irq(MVME147_IRQ_SCCB_TX, scc_tx_int, IRQF_DISABLED,
"SCC-B TX", port);
request_irq(MVME147_IRQ_SCCB_STAT, scc_stat_int, IRQF_DISABLED,
"SCC-B status", port);
request_irq(MVME147_IRQ_SCCB_RX, scc_rx_int, IRQF_DISABLED,
"SCC-B RX", port);
request_irq(MVME147_IRQ_SCCB_SPCOND, scc_spcond_int, IRQF_DISABLED,
"SCC-B special cond", port);
{
SCC_ACCESS_INIT(port);
/* disable interrupts for this channel */
SCCwrite(INT_AND_DMA_REG, 0);
}
/* Ensure interrupts are enabled in the PCC chip */
m147_pcc->serial_cntrl=PCC_LEVEL_SERIAL|PCC_INT_ENAB;
/* Initialise the tty driver structures and register */
scc_init_portstructs();
scc_init_drivers();
return 0;
}
#endif
#ifdef CONFIG_MVME162_SCC
static int mvme162_scc_init(void)
{
struct scc_port *port;
if (!(mvme16x_config & MVME16x_CONFIG_GOT_SCCA))
return (-ENODEV);
printk(KERN_INFO "SCC: MVME162 Serial Driver\n");
/* Init channel A */
port = &scc_ports[0];
port->channel = CHANNEL_A;
port->ctrlp = (volatile unsigned char *)MVME_SCC_A_ADDR;
port->datap = port->ctrlp + 2;
port->port_a = &scc_ports[0];
port->port_b = &scc_ports[1];
request_irq(MVME162_IRQ_SCCA_TX, scc_tx_int, IRQF_DISABLED,
"SCC-A TX", port);
request_irq(MVME162_IRQ_SCCA_STAT, scc_stat_int, IRQF_DISABLED,
"SCC-A status", port);
request_irq(MVME162_IRQ_SCCA_RX, scc_rx_int, IRQF_DISABLED,
"SCC-A RX", port);
request_irq(MVME162_IRQ_SCCA_SPCOND, scc_spcond_int, IRQF_DISABLED,
"SCC-A special cond", port);
{
SCC_ACCESS_INIT(port);
/* disable interrupts for this channel */
SCCwrite(INT_AND_DMA_REG, 0);
/* Set the interrupt vector */
SCCwrite(INT_VECTOR_REG, MVME162_IRQ_SCC_BASE);
/* Interrupt parameters: vector includes status, status low */
SCCwrite(MASTER_INT_CTRL, MIC_VEC_INCL_STAT);
SCCmod(MASTER_INT_CTRL, 0xff, MIC_MASTER_INT_ENAB);
}
/* Init channel B */
port = &scc_ports[1];
port->channel = CHANNEL_B;
port->ctrlp = (volatile unsigned char *)MVME_SCC_B_ADDR;
port->datap = port->ctrlp + 2;
port->port_a = &scc_ports[0];
port->port_b = &scc_ports[1];
request_irq(MVME162_IRQ_SCCB_TX, scc_tx_int, IRQF_DISABLED,
"SCC-B TX", port);
request_irq(MVME162_IRQ_SCCB_STAT, scc_stat_int, IRQF_DISABLED,
"SCC-B status", port);
request_irq(MVME162_IRQ_SCCB_RX, scc_rx_int, IRQF_DISABLED,
"SCC-B RX", port);
request_irq(MVME162_IRQ_SCCB_SPCOND, scc_spcond_int, IRQF_DISABLED,
"SCC-B special cond", port);
{
SCC_ACCESS_INIT(port); /* Either channel will do */
/* disable interrupts for this channel */
SCCwrite(INT_AND_DMA_REG, 0);
}
/* Ensure interrupts are enabled in the MC2 chip */
*(volatile char *)0xfff4201d = 0x14;
/* Initialise the tty driver structures and register */
scc_init_portstructs();
scc_init_drivers();
return 0;
}
#endif
#ifdef CONFIG_BVME6000_SCC
static int bvme6000_scc_init(void)
{
struct scc_port *port;
printk(KERN_INFO "SCC: BVME6000 Serial Driver\n");
/* Init channel A */
port = &scc_ports[0];
port->channel = CHANNEL_A;
port->ctrlp = (volatile unsigned char *)BVME_SCC_A_ADDR;
port->datap = port->ctrlp + 4;
port->port_a = &scc_ports[0];
port->port_b = &scc_ports[1];
request_irq(BVME_IRQ_SCCA_TX, scc_tx_int, IRQF_DISABLED,
"SCC-A TX", port);
request_irq(BVME_IRQ_SCCA_STAT, scc_stat_int, IRQF_DISABLED,
"SCC-A status", port);
request_irq(BVME_IRQ_SCCA_RX, scc_rx_int, IRQF_DISABLED,
"SCC-A RX", port);
request_irq(BVME_IRQ_SCCA_SPCOND, scc_spcond_int, IRQF_DISABLED,
"SCC-A special cond", port);
{
SCC_ACCESS_INIT(port);
/* disable interrupts for this channel */
SCCwrite(INT_AND_DMA_REG, 0);
/* Set the interrupt vector */
SCCwrite(INT_VECTOR_REG, BVME_IRQ_SCC_BASE);
/* Interrupt parameters: vector includes status, status low */
SCCwrite(MASTER_INT_CTRL, MIC_VEC_INCL_STAT);
SCCmod(MASTER_INT_CTRL, 0xff, MIC_MASTER_INT_ENAB);
}
/* Init channel B */
port = &scc_ports[1];
port->channel = CHANNEL_B;
port->ctrlp = (volatile unsigned char *)BVME_SCC_B_ADDR;
port->datap = port->ctrlp + 4;
port->port_a = &scc_ports[0];
port->port_b = &scc_ports[1];
request_irq(BVME_IRQ_SCCB_TX, scc_tx_int, IRQF_DISABLED,
"SCC-B TX", port);
request_irq(BVME_IRQ_SCCB_STAT, scc_stat_int, IRQF_DISABLED,
"SCC-B status", port);
request_irq(BVME_IRQ_SCCB_RX, scc_rx_int, IRQF_DISABLED,
"SCC-B RX", port);
request_irq(BVME_IRQ_SCCB_SPCOND, scc_spcond_int, IRQF_DISABLED,
"SCC-B special cond", port);
{
SCC_ACCESS_INIT(port); /* Either channel will do */
/* disable interrupts for this channel */
SCCwrite(INT_AND_DMA_REG, 0);
}
/* Initialise the tty driver structures and register */
scc_init_portstructs();
scc_init_drivers();
return 0;
}
#endif
static int vme_scc_init(void)
{
int res = -ENODEV;
#ifdef CONFIG_MVME147_SCC
if (MACH_IS_MVME147)
res = mvme147_scc_init();
#endif
#ifdef CONFIG_MVME162_SCC
if (MACH_IS_MVME16x)
res = mvme162_scc_init();
#endif
#ifdef CONFIG_BVME6000_SCC
if (MACH_IS_BVME6000)
res = bvme6000_scc_init();
#endif
return res;
}
module_init(vme_scc_init);
/*---------------------------------------------------------------------------
* Interrupt handlers
*--------------------------------------------------------------------------*/
static irqreturn_t scc_rx_int(int irq, void *data)
{
unsigned char ch;
struct scc_port *port = data;
struct tty_struct *tty = port->gs.tty;
SCC_ACCESS_INIT(port);
ch = SCCread_NB(RX_DATA_REG);
if (!tty) {
printk(KERN_WARNING "scc_rx_int with NULL tty!\n");
SCCwrite_NB(COMMAND_REG, CR_HIGHEST_IUS_RESET);
return IRQ_HANDLED;
}
tty_insert_flip_char(tty, ch, 0);
/* Check if another character is already ready; in that case, the
* spcond_int() function must be used, because this character may have an
* error condition that isn't signalled by the interrupt vector used!
*/
if (SCCread(INT_PENDING_REG) &
(port->channel == CHANNEL_A ? IPR_A_RX : IPR_B_RX)) {
scc_spcond_int (irq, data);
return IRQ_HANDLED;
}
SCCwrite_NB(COMMAND_REG, CR_HIGHEST_IUS_RESET);
tty_flip_buffer_push(tty);
return IRQ_HANDLED;
}
static irqreturn_t scc_spcond_int(int irq, void *data)
{
struct scc_port *port = data;
struct tty_struct *tty = port->gs.tty;
unsigned char stat, ch, err;
int int_pending_mask = port->channel == CHANNEL_A ?
IPR_A_RX : IPR_B_RX;
SCC_ACCESS_INIT(port);
if (!tty) {
printk(KERN_WARNING "scc_spcond_int with NULL tty!\n");
SCCwrite(COMMAND_REG, CR_ERROR_RESET);
SCCwrite_NB(COMMAND_REG, CR_HIGHEST_IUS_RESET);
return IRQ_HANDLED;
}
do {
stat = SCCread(SPCOND_STATUS_REG);
ch = SCCread_NB(RX_DATA_REG);
if (stat & SCSR_RX_OVERRUN)
err = TTY_OVERRUN;
else if (stat & SCSR_PARITY_ERR)
err = TTY_PARITY;
else if (stat & SCSR_CRC_FRAME_ERR)
err = TTY_FRAME;
else
err = 0;
tty_insert_flip_char(tty, ch, err);
/* ++TeSche: *All* errors have to be cleared manually,
* else the condition persists for the next chars
*/
if (err)
SCCwrite(COMMAND_REG, CR_ERROR_RESET);
} while(SCCread(INT_PENDING_REG) & int_pending_mask);
SCCwrite_NB(COMMAND_REG, CR_HIGHEST_IUS_RESET);
tty_flip_buffer_push(tty);
return IRQ_HANDLED;
}
static irqreturn_t scc_tx_int(int irq, void *data)
{
struct scc_port *port = data;
SCC_ACCESS_INIT(port);
if (!port->gs.tty) {
printk(KERN_WARNING "scc_tx_int with NULL tty!\n");
SCCmod (INT_AND_DMA_REG, ~IDR_TX_INT_ENAB, 0);
SCCwrite(COMMAND_REG, CR_TX_PENDING_RESET);
SCCwrite_NB(COMMAND_REG, CR_HIGHEST_IUS_RESET);
return IRQ_HANDLED;
}
while ((SCCread_NB(STATUS_REG) & SR_TX_BUF_EMPTY)) {
if (port->x_char) {
SCCwrite(TX_DATA_REG, port->x_char);
port->x_char = 0;
}
else if ((port->gs.xmit_cnt <= 0) || port->gs.tty->stopped ||
port->gs.tty->hw_stopped)
break;
else {
SCCwrite(TX_DATA_REG, port->gs.xmit_buf[port->gs.xmit_tail++]);
port->gs.xmit_tail = port->gs.xmit_tail & (SERIAL_XMIT_SIZE-1);
if (--port->gs.xmit_cnt <= 0)
break;
}
}
if ((port->gs.xmit_cnt <= 0) || port->gs.tty->stopped ||
port->gs.tty->hw_stopped) {
/* disable tx interrupts */
SCCmod (INT_AND_DMA_REG, ~IDR_TX_INT_ENAB, 0);
SCCwrite(COMMAND_REG, CR_TX_PENDING_RESET); /* disable tx_int on next tx underrun? */
port->gs.flags &= ~GS_TX_INTEN;
}
if (port->gs.tty && port->gs.xmit_cnt <= port->gs.wakeup_chars)
tty_wakeup(port->gs.tty);
SCCwrite_NB(COMMAND_REG, CR_HIGHEST_IUS_RESET);
return IRQ_HANDLED;
}
static irqreturn_t scc_stat_int(int irq, void *data)
{
struct scc_port *port = data;
unsigned channel = port->channel;
unsigned char last_sr, sr, changed;
SCC_ACCESS_INIT(port);
last_sr = scc_last_status_reg[channel];
sr = scc_last_status_reg[channel] = SCCread_NB(STATUS_REG);
changed = last_sr ^ sr;
if (changed & SR_DCD) {
port->c_dcd = !!(sr & SR_DCD);
if (!(port->gs.flags & ASYNC_CHECK_CD))
; /* Don't report DCD changes */
else if (port->c_dcd) {
wake_up_interruptible(&port->gs.open_wait);
}
else {
if (port->gs.tty)
tty_hangup (port->gs.tty);
}
}
SCCwrite(COMMAND_REG, CR_EXTSTAT_RESET);
SCCwrite_NB(COMMAND_REG, CR_HIGHEST_IUS_RESET);
return IRQ_HANDLED;
}
/*---------------------------------------------------------------------------
* generic_serial.c callback funtions
*--------------------------------------------------------------------------*/
static void scc_disable_tx_interrupts(void *ptr)
{
struct scc_port *port = ptr;
unsigned long flags;
SCC_ACCESS_INIT(port);
local_irq_save(flags);
SCCmod(INT_AND_DMA_REG, ~IDR_TX_INT_ENAB, 0);
port->gs.flags &= ~GS_TX_INTEN;
local_irq_restore(flags);
}
static void scc_enable_tx_interrupts(void *ptr)
{
struct scc_port *port = ptr;
unsigned long flags;
SCC_ACCESS_INIT(port);
local_irq_save(flags);
SCCmod(INT_AND_DMA_REG, 0xff, IDR_TX_INT_ENAB);
/* restart the transmitter */
scc_tx_int (0, port);
local_irq_restore(flags);
}
static void scc_disable_rx_interrupts(void *ptr)
{
struct scc_port *port = ptr;
unsigned long flags;
SCC_ACCESS_INIT(port);
local_irq_save(flags);
SCCmod(INT_AND_DMA_REG,
~(IDR_RX_INT_MASK|IDR_PARERR_AS_SPCOND|IDR_EXTSTAT_INT_ENAB), 0);
local_irq_restore(flags);
}
static void scc_enable_rx_interrupts(void *ptr)
{
struct scc_port *port = ptr;
unsigned long flags;
SCC_ACCESS_INIT(port);
local_irq_save(flags);
SCCmod(INT_AND_DMA_REG, 0xff,
IDR_EXTSTAT_INT_ENAB|IDR_PARERR_AS_SPCOND|IDR_RX_INT_ALL);
local_irq_restore(flags);
}
static int scc_get_CD(void *ptr)
{
struct scc_port *port = ptr;
unsigned channel = port->channel;
return !!(scc_last_status_reg[channel] & SR_DCD);
}
static void scc_shutdown_port(void *ptr)
{
struct scc_port *port = ptr;
port->gs.flags &= ~ GS_ACTIVE;
if (port->gs.tty && port->gs.tty->termios->c_cflag & HUPCL) {
scc_setsignals (port, 0, 0);
}
}
static int scc_set_real_termios (void *ptr)
{
/* the SCC has char sizes 5,7,6,8 in that order! */
static int chsize_map[4] = { 0, 2, 1, 3 };
unsigned cflag, baud, chsize, channel, brgval = 0;
unsigned long flags;
struct scc_port *port = ptr;
SCC_ACCESS_INIT(port);
if (!port->gs.tty || !port->gs.tty->termios) return 0;
channel = port->channel;
if (channel == CHANNEL_A)
return 0; /* Settings controlled by boot PROM */
cflag = port->gs.tty->termios->c_cflag;
baud = port->gs.baud;
chsize = (cflag & CSIZE) >> 4;
if (baud == 0) {
/* speed == 0 -> drop DTR */
local_irq_save(flags);
SCCmod(TX_CTRL_REG, ~TCR_DTR, 0);
local_irq_restore(flags);
return 0;
}
else if ((MACH_IS_MVME16x && (baud < 50 || baud > 38400)) ||
(MACH_IS_MVME147 && (baud < 50 || baud > 19200)) ||
(MACH_IS_BVME6000 &&(baud < 50 || baud > 76800))) {
printk(KERN_NOTICE "SCC: Bad speed requested, %d\n", baud);
return 0;
}
if (cflag & CLOCAL)
port->gs.flags &= ~ASYNC_CHECK_CD;
else
port->gs.flags |= ASYNC_CHECK_CD;
#ifdef CONFIG_MVME147_SCC
if (MACH_IS_MVME147)
brgval = (M147_SCC_PCLK + baud/2) / (16 * 2 * baud) - 2;
#endif
#ifdef CONFIG_MVME162_SCC
if (MACH_IS_MVME16x)
brgval = (MVME_SCC_PCLK + baud/2) / (16 * 2 * baud) - 2;
#endif
#ifdef CONFIG_BVME6000_SCC
if (MACH_IS_BVME6000)
brgval = (BVME_SCC_RTxC + baud/2) / (16 * 2 * baud) - 2;
#endif
/* Now we have all parameters and can go to set them: */
local_irq_save(flags);
/* receiver's character size and auto-enables */
SCCmod(RX_CTRL_REG, ~(RCR_CHSIZE_MASK|RCR_AUTO_ENAB_MODE),
(chsize_map[chsize] << 6) |
((cflag & CRTSCTS) ? RCR_AUTO_ENAB_MODE : 0));
/* parity and stop bits (both, Tx and Rx), clock mode never changes */
SCCmod (AUX1_CTRL_REG,
~(A1CR_PARITY_MASK | A1CR_MODE_MASK),
((cflag & PARENB
? (cflag & PARODD ? A1CR_PARITY_ODD : A1CR_PARITY_EVEN)
: A1CR_PARITY_NONE)
| (cflag & CSTOPB ? A1CR_MODE_ASYNC_2 : A1CR_MODE_ASYNC_1)));
/* sender's character size, set DTR for valid baud rate */
SCCmod(TX_CTRL_REG, ~TCR_CHSIZE_MASK, chsize_map[chsize] << 5 | TCR_DTR);
/* clock sources never change */
/* disable BRG before changing the value */
SCCmod(DPLL_CTRL_REG, ~DCR_BRG_ENAB, 0);
/* BRG value */
SCCwrite(TIMER_LOW_REG, brgval & 0xff);
SCCwrite(TIMER_HIGH_REG, (brgval >> 8) & 0xff);
/* BRG enable, and clock source never changes */
SCCmod(DPLL_CTRL_REG, 0xff, DCR_BRG_ENAB);
local_irq_restore(flags);
return 0;
}
static int scc_chars_in_buffer (void *ptr)
{
struct scc_port *port = ptr;
SCC_ACCESS_INIT(port);
return (SCCread (SPCOND_STATUS_REG) & SCSR_ALL_SENT) ? 0 : 1;
}
/* Comment taken from sx.c (2.4.0):
I haven't the foggiest why the decrement use count has to happen
here. The whole linux serial drivers stuff needs to be redesigned.
My guess is that this is a hack to minimize the impact of a bug
elsewhere. Thinking about it some more. (try it sometime) Try
running minicom on a serial port that is driven by a modularized
driver. Have the modem hangup. Then remove the driver module. Then
exit minicom. I expect an "oops". -- REW */
static void scc_hungup(void *ptr)
{
scc_disable_tx_interrupts(ptr);
scc_disable_rx_interrupts(ptr);
}
static void scc_close(void *ptr)
{
scc_disable_tx_interrupts(ptr);
scc_disable_rx_interrupts(ptr);
}
/*---------------------------------------------------------------------------
* Internal support functions
*--------------------------------------------------------------------------*/
static void scc_setsignals(struct scc_port *port, int dtr, int rts)
{
unsigned long flags;
unsigned char t;
SCC_ACCESS_INIT(port);
local_irq_save(flags);
t = SCCread(TX_CTRL_REG);
if (dtr >= 0) t = dtr? (t | TCR_DTR): (t & ~TCR_DTR);
if (rts >= 0) t = rts? (t | TCR_RTS): (t & ~TCR_RTS);
SCCwrite(TX_CTRL_REG, t);
local_irq_restore(flags);
}
static void scc_send_xchar(struct tty_struct *tty, char ch)
{
struct scc_port *port = (struct scc_port *)tty->driver_data;
port->x_char = ch;
if (ch)
scc_enable_tx_interrupts(port);
}
/*---------------------------------------------------------------------------
* Driver entrypoints referenced from above
*--------------------------------------------------------------------------*/
static int scc_open (struct tty_struct * tty, struct file * filp)
{
int line = tty->index;
int retval;
struct scc_port *port = &scc_ports[line];
int i, channel = port->channel;
unsigned long flags;
SCC_ACCESS_INIT(port);
#if defined(CONFIG_MVME162_SCC) || defined(CONFIG_MVME147_SCC)
static const struct {
unsigned reg, val;
} mvme_init_tab[] = {
/* Values for MVME162 and MVME147 */
/* no parity, 1 stop bit, async, 1:16 */
{ AUX1_CTRL_REG, A1CR_PARITY_NONE|A1CR_MODE_ASYNC_1|A1CR_CLKMODE_x16 },
/* parity error is special cond, ints disabled, no DMA */
{ INT_AND_DMA_REG, IDR_PARERR_AS_SPCOND | IDR_RX_INT_DISAB },
/* Rx 8 bits/char, no auto enable, Rx off */
{ RX_CTRL_REG, RCR_CHSIZE_8 },
/* DTR off, Tx 8 bits/char, RTS off, Tx off */
{ TX_CTRL_REG, TCR_CHSIZE_8 },
/* special features off */
{ AUX2_CTRL_REG, 0 },
{ CLK_CTRL_REG, CCR_RXCLK_BRG | CCR_TXCLK_BRG },
{ DPLL_CTRL_REG, DCR_BRG_ENAB | DCR_BRG_USE_PCLK },
/* Start Rx */
{ RX_CTRL_REG, RCR_RX_ENAB | RCR_CHSIZE_8 },
/* Start Tx */
{ TX_CTRL_REG, TCR_TX_ENAB | TCR_RTS | TCR_DTR | TCR_CHSIZE_8 },
/* Ext/Stat ints: DCD only */
{ INT_CTRL_REG, ICR_ENAB_DCD_INT },
/* Reset Ext/Stat ints */
{ COMMAND_REG, CR_EXTSTAT_RESET },
/* ...again */
{ COMMAND_REG, CR_EXTSTAT_RESET },
};
#endif
#if defined(CONFIG_BVME6000_SCC)
static const struct {
unsigned reg, val;
} bvme_init_tab[] = {
/* Values for BVME6000 */
/* no parity, 1 stop bit, async, 1:16 */
{ AUX1_CTRL_REG, A1CR_PARITY_NONE|A1CR_MODE_ASYNC_1|A1CR_CLKMODE_x16 },
/* parity error is special cond, ints disabled, no DMA */
{ INT_AND_DMA_REG, IDR_PARERR_AS_SPCOND | IDR_RX_INT_DISAB },
/* Rx 8 bits/char, no auto enable, Rx off */
{ RX_CTRL_REG, RCR_CHSIZE_8 },
/* DTR off, Tx 8 bits/char, RTS off, Tx off */
{ TX_CTRL_REG, TCR_CHSIZE_8 },
/* special features off */
{ AUX2_CTRL_REG, 0 },
{ CLK_CTRL_REG, CCR_RTxC_XTAL | CCR_RXCLK_BRG | CCR_TXCLK_BRG },
{ DPLL_CTRL_REG, DCR_BRG_ENAB },
/* Start Rx */
{ RX_CTRL_REG, RCR_RX_ENAB | RCR_CHSIZE_8 },
/* Start Tx */
{ TX_CTRL_REG, TCR_TX_ENAB | TCR_RTS | TCR_DTR | TCR_CHSIZE_8 },
/* Ext/Stat ints: DCD only */
{ INT_CTRL_REG, ICR_ENAB_DCD_INT },
/* Reset Ext/Stat ints */
{ COMMAND_REG, CR_EXTSTAT_RESET },
/* ...again */
{ COMMAND_REG, CR_EXTSTAT_RESET },
};
#endif
if (!(port->gs.flags & ASYNC_INITIALIZED)) {
local_irq_save(flags);
#if defined(CONFIG_MVME147_SCC) || defined(CONFIG_MVME162_SCC)
if (MACH_IS_MVME147 || MACH_IS_MVME16x) {
for (i = 0; i < ARRAY_SIZE(mvme_init_tab); ++i)
SCCwrite(mvme_init_tab[i].reg, mvme_init_tab[i].val);
}
#endif
#if defined(CONFIG_BVME6000_SCC)
if (MACH_IS_BVME6000) {
for (i = 0; i < ARRAY_SIZE(bvme_init_tab); ++i)
SCCwrite(bvme_init_tab[i].reg, bvme_init_tab[i].val);
}
#endif
/* remember status register for detection of DCD and CTS changes */
scc_last_status_reg[channel] = SCCread(STATUS_REG);
port->c_dcd = 0; /* Prevent initial 1->0 interrupt */
scc_setsignals (port, 1,1);
local_irq_restore(flags);
}
tty->driver_data = port;
port->gs.tty = tty;
port->gs.count++;
retval = gs_init_port(&port->gs);
if (retval) {
port->gs.count--;
return retval;
}
port->gs.flags |= GS_ACTIVE;
retval = gs_block_til_ready(port, filp);
if (retval) {
port->gs.count--;
return retval;
}
port->c_dcd = scc_get_CD (port);
scc_enable_rx_interrupts(port);
return 0;
}
static void scc_throttle (struct tty_struct * tty)
{
struct scc_port *port = (struct scc_port *)tty->driver_data;
unsigned long flags;
SCC_ACCESS_INIT(port);
if (tty->termios->c_cflag & CRTSCTS) {
local_irq_save(flags);
SCCmod(TX_CTRL_REG, ~TCR_RTS, 0);
local_irq_restore(flags);
}
if (I_IXOFF(tty))
scc_send_xchar(tty, STOP_CHAR(tty));
}
static void scc_unthrottle (struct tty_struct * tty)
{
struct scc_port *port = (struct scc_port *)tty->driver_data;
unsigned long flags;
SCC_ACCESS_INIT(port);
if (tty->termios->c_cflag & CRTSCTS) {
local_irq_save(flags);
SCCmod(TX_CTRL_REG, 0xff, TCR_RTS);
local_irq_restore(flags);
}
if (I_IXOFF(tty))
scc_send_xchar(tty, START_CHAR(tty));
}
static int scc_ioctl(struct tty_struct *tty, struct file *file,
unsigned int cmd, unsigned long arg)
{
return -ENOIOCTLCMD;
}
static int scc_break_ctl(struct tty_struct *tty, int break_state)
{
struct scc_port *port = (struct scc_port *)tty->driver_data;
unsigned long flags;
SCC_ACCESS_INIT(port);
local_irq_save(flags);
SCCmod(TX_CTRL_REG, ~TCR_SEND_BREAK,
break_state ? TCR_SEND_BREAK : 0);
local_irq_restore(flags);
return 0;
}
/*---------------------------------------------------------------------------
* Serial console stuff...
*--------------------------------------------------------------------------*/
#define scc_delay() do { __asm__ __volatile__ (" nop; nop"); } while (0)
static void scc_ch_write (char ch)
{
volatile char *p = NULL;
#ifdef CONFIG_MVME147_SCC
if (MACH_IS_MVME147)
p = (volatile char *)M147_SCC_A_ADDR;
#endif
#ifdef CONFIG_MVME162_SCC
if (MACH_IS_MVME16x)
p = (volatile char *)MVME_SCC_A_ADDR;
#endif
#ifdef CONFIG_BVME6000_SCC
if (MACH_IS_BVME6000)
p = (volatile char *)BVME_SCC_A_ADDR;
#endif
do {
scc_delay();
}
while (!(*p & 4));
scc_delay();
*p = 8;
scc_delay();
*p = ch;
}
/* The console must be locked when we get here. */
static void scc_console_write (struct console *co, const char *str, unsigned count)
{
unsigned long flags;
local_irq_save(flags);
while (count--)
{
if (*str == '\n')
scc_ch_write ('\r');
scc_ch_write (*str++);
}
local_irq_restore(flags);
}
static struct tty_driver *scc_console_device(struct console *c, int *index)
{
*index = c->index;
return scc_driver;
}
static struct console sercons = {
.name = "ttyS",
.write = scc_console_write,
.device = scc_console_device,
.flags = CON_PRINTBUFFER,
.index = -1,
};
static int __init vme_scc_console_init(void)
{
if (vme_brdtype == VME_TYPE_MVME147 ||
vme_brdtype == VME_TYPE_MVME162 ||
vme_brdtype == VME_TYPE_MVME172 ||
vme_brdtype == VME_TYPE_BVME4000 ||
vme_brdtype == VME_TYPE_BVME6000)
register_console(&sercons);
return 0;
}
console_initcall(vme_scc_console_init);
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