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crisv10.c
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/*
* Serial port driver for the ETRAX 100LX chip
*
* Copyright (C) 1998-2007 Axis Communications AB
*
* Many, many authors. Based once upon a time on serial.c for 16x50.
*
*/
static char *serial_version = "$Revision: 1.25 $";
#include <linux/types.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/major.h>
#include <linux/smp_lock.h>
#include <linux/string.h>
#include <linux/fcntl.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/mutex.h>
#include <linux/bitops.h>
#include <linux/seq_file.h>
#include <linux/delay.h>
#include <linux/module.h>
#include <linux/uaccess.h>
#include <linux/io.h>
#include <asm/irq.h>
#include <asm/dma.h>
#include <asm/system.h>
#include <arch/svinto.h>
/* non-arch dependent serial structures are in linux/serial.h */
#include <linux/serial.h>
/* while we keep our own stuff (struct e100_serial) in a local .h file */
#include "crisv10.h"
#include <asm/fasttimer.h>
#include <arch/io_interface_mux.h>
#ifdef CONFIG_ETRAX_SERIAL_FAST_TIMER
#ifndef CONFIG_ETRAX_FAST_TIMER
#error "Enable FAST_TIMER to use SERIAL_FAST_TIMER"
#endif
#endif
#if defined(CONFIG_ETRAX_SERIAL_RX_TIMEOUT_TICKS) && \
(CONFIG_ETRAX_SERIAL_RX_TIMEOUT_TICKS == 0)
#error "RX_TIMEOUT_TICKS == 0 not allowed, use 1"
#endif
#if defined(CONFIG_ETRAX_RS485_ON_PA) && defined(CONFIG_ETRAX_RS485_ON_PORT_G)
#error "Disable either CONFIG_ETRAX_RS485_ON_PA or CONFIG_ETRAX_RS485_ON_PORT_G"
#endif
/*
* All of the compatibilty code so we can compile serial.c against
* older kernels is hidden in serial_compat.h
*/
#if defined(LOCAL_HEADERS)
#include "serial_compat.h"
#endif
struct tty_driver *serial_driver;
/* number of characters left in xmit buffer before we ask for more */
#define WAKEUP_CHARS 256
//#define SERIAL_DEBUG_INTR
//#define SERIAL_DEBUG_OPEN
//#define SERIAL_DEBUG_FLOW
//#define SERIAL_DEBUG_DATA
//#define SERIAL_DEBUG_THROTTLE
//#define SERIAL_DEBUG_IO /* Debug for Extra control and status pins */
//#define SERIAL_DEBUG_LINE 0 /* What serport we want to debug */
/* Enable this to use serial interrupts to handle when you
expect the first received event on the serial port to
be an error, break or similar. Used to be able to flash IRMA
from eLinux */
#define SERIAL_HANDLE_EARLY_ERRORS
/* Currently 16 descriptors x 128 bytes = 2048 bytes */
#define SERIAL_DESCR_BUF_SIZE 256
#define SERIAL_PRESCALE_BASE 3125000 /* 3.125MHz */
#define DEF_BAUD_BASE SERIAL_PRESCALE_BASE
/* We don't want to load the system with massive fast timer interrupt
* on high baudrates so limit it to 250 us (4kHz) */
#define MIN_FLUSH_TIME_USEC 250
/* Add an x here to log a lot of timer stuff */
#define TIMERD(x)
/* Debug details of interrupt handling */
#define DINTR1(x) /* irq on/off, errors */
#define DINTR2(x) /* tx and rx */
/* Debug flip buffer stuff */
#define DFLIP(x)
/* Debug flow control and overview of data flow */
#define DFLOW(x)
#define DBAUD(x)
#define DLOG_INT_TRIG(x)
//#define DEBUG_LOG_INCLUDED
#ifndef DEBUG_LOG_INCLUDED
#define DEBUG_LOG(line, string, value)
#else
struct debug_log_info
{
unsigned long time;
unsigned long timer_data;
// int line;
const char *string;
int value;
};
#define DEBUG_LOG_SIZE 4096
struct debug_log_info debug_log[DEBUG_LOG_SIZE];
int debug_log_pos = 0;
#define DEBUG_LOG(_line, _string, _value) do { \
if ((_line) == SERIAL_DEBUG_LINE) {\
debug_log_func(_line, _string, _value); \
}\
}while(0)
void debug_log_func(int line, const char *string, int value)
{
if (debug_log_pos < DEBUG_LOG_SIZE) {
debug_log[debug_log_pos].time = jiffies;
debug_log[debug_log_pos].timer_data = *R_TIMER_DATA;
// debug_log[debug_log_pos].line = line;
debug_log[debug_log_pos].string = string;
debug_log[debug_log_pos].value = value;
debug_log_pos++;
}
/*printk(string, value);*/
}
#endif
#ifndef CONFIG_ETRAX_SERIAL_RX_TIMEOUT_TICKS
/* Default number of timer ticks before flushing rx fifo
* When using "little data, low latency applications: use 0
* When using "much data applications (PPP)" use ~5
*/
#define CONFIG_ETRAX_SERIAL_RX_TIMEOUT_TICKS 5
#endif
unsigned long timer_data_to_ns(unsigned long timer_data);
static void change_speed(struct e100_serial *info);
static void rs_throttle(struct tty_struct * tty);
static void rs_wait_until_sent(struct tty_struct *tty, int timeout);
static int rs_write(struct tty_struct *tty,
const unsigned char *buf, int count);
#ifdef CONFIG_ETRAX_RS485
static int e100_write_rs485(struct tty_struct *tty,
const unsigned char *buf, int count);
#endif
static int get_lsr_info(struct e100_serial *info, unsigned int *value);
#define DEF_BAUD 115200 /* 115.2 kbit/s */
#define STD_FLAGS (ASYNC_BOOT_AUTOCONF | ASYNC_SKIP_TEST)
#define DEF_RX 0x20 /* or SERIAL_CTRL_W >> 8 */
/* Default value of tx_ctrl register: has txd(bit 7)=1 (idle) as default */
#define DEF_TX 0x80 /* or SERIAL_CTRL_B */
/* offsets from R_SERIALx_CTRL */
#define REG_DATA 0
#define REG_DATA_STATUS32 0 /* this is the 32 bit register R_SERIALx_READ */
#define REG_TR_DATA 0
#define REG_STATUS 1
#define REG_TR_CTRL 1
#define REG_REC_CTRL 2
#define REG_BAUD 3
#define REG_XOFF 4 /* this is a 32 bit register */
/* The bitfields are the same for all serial ports */
#define SER_RXD_MASK IO_MASK(R_SERIAL0_STATUS, rxd)
#define SER_DATA_AVAIL_MASK IO_MASK(R_SERIAL0_STATUS, data_avail)
#define SER_FRAMING_ERR_MASK IO_MASK(R_SERIAL0_STATUS, framing_err)
#define SER_PAR_ERR_MASK IO_MASK(R_SERIAL0_STATUS, par_err)
#define SER_OVERRUN_MASK IO_MASK(R_SERIAL0_STATUS, overrun)
#define SER_ERROR_MASK (SER_OVERRUN_MASK | SER_PAR_ERR_MASK | SER_FRAMING_ERR_MASK)
/* Values for info->errorcode */
#define ERRCODE_SET_BREAK (TTY_BREAK)
#define ERRCODE_INSERT 0x100
#define ERRCODE_INSERT_BREAK (ERRCODE_INSERT | TTY_BREAK)
#define FORCE_EOP(info) *R_SET_EOP = 1U << info->iseteop;
/*
* General note regarding the use of IO_* macros in this file:
*
* We will use the bits defined for DMA channel 6 when using various
* IO_* macros (e.g. IO_STATE, IO_MASK, IO_EXTRACT) and _assume_ they are
* the same for all channels (which of course they are).
*
* We will also use the bits defined for serial port 0 when writing commands
* to the different ports, as these bits too are the same for all ports.
*/
/* Mask for the irqs possibly enabled in R_IRQ_MASK1_RD etc. */
static const unsigned long e100_ser_int_mask = 0
#ifdef CONFIG_ETRAX_SERIAL_PORT0
| IO_MASK(R_IRQ_MASK1_RD, ser0_data) | IO_MASK(R_IRQ_MASK1_RD, ser0_ready)
#endif
#ifdef CONFIG_ETRAX_SERIAL_PORT1
| IO_MASK(R_IRQ_MASK1_RD, ser1_data) | IO_MASK(R_IRQ_MASK1_RD, ser1_ready)
#endif
#ifdef CONFIG_ETRAX_SERIAL_PORT2
| IO_MASK(R_IRQ_MASK1_RD, ser2_data) | IO_MASK(R_IRQ_MASK1_RD, ser2_ready)
#endif
#ifdef CONFIG_ETRAX_SERIAL_PORT3
| IO_MASK(R_IRQ_MASK1_RD, ser3_data) | IO_MASK(R_IRQ_MASK1_RD, ser3_ready)
#endif
;
unsigned long r_alt_ser_baudrate_shadow = 0;
/* this is the data for the four serial ports in the etrax100 */
/* DMA2(ser2), DMA4(ser3), DMA6(ser0) or DMA8(ser1) */
/* R_DMA_CHx_CLR_INTR, R_DMA_CHx_FIRST, R_DMA_CHx_CMD */
static struct e100_serial rs_table[] = {
{ .baud = DEF_BAUD,
.ioport = (unsigned char *)R_SERIAL0_CTRL,
.irq = 1U << 12, /* uses DMA 6 and 7 */
.oclrintradr = R_DMA_CH6_CLR_INTR,
.ofirstadr = R_DMA_CH6_FIRST,
.ocmdadr = R_DMA_CH6_CMD,
.ostatusadr = R_DMA_CH6_STATUS,
.iclrintradr = R_DMA_CH7_CLR_INTR,
.ifirstadr = R_DMA_CH7_FIRST,
.icmdadr = R_DMA_CH7_CMD,
.idescradr = R_DMA_CH7_DESCR,
.flags = STD_FLAGS,
.rx_ctrl = DEF_RX,
.tx_ctrl = DEF_TX,
.iseteop = 2,
.dma_owner = dma_ser0,
.io_if = if_serial_0,
#ifdef CONFIG_ETRAX_SERIAL_PORT0
.enabled = 1,
#ifdef CONFIG_ETRAX_SERIAL_PORT0_DMA6_OUT
.dma_out_enabled = 1,
.dma_out_nbr = SER0_TX_DMA_NBR,
.dma_out_irq_nbr = SER0_DMA_TX_IRQ_NBR,
.dma_out_irq_flags = IRQF_DISABLED,
.dma_out_irq_description = "serial 0 dma tr",
#else
.dma_out_enabled = 0,
.dma_out_nbr = UINT_MAX,
.dma_out_irq_nbr = 0,
.dma_out_irq_flags = 0,
.dma_out_irq_description = NULL,
#endif
#ifdef CONFIG_ETRAX_SERIAL_PORT0_DMA7_IN
.dma_in_enabled = 1,
.dma_in_nbr = SER0_RX_DMA_NBR,
.dma_in_irq_nbr = SER0_DMA_RX_IRQ_NBR,
.dma_in_irq_flags = IRQF_DISABLED,
.dma_in_irq_description = "serial 0 dma rec",
#else
.dma_in_enabled = 0,
.dma_in_nbr = UINT_MAX,
.dma_in_irq_nbr = 0,
.dma_in_irq_flags = 0,
.dma_in_irq_description = NULL,
#endif
#else
.enabled = 0,
.io_if_description = NULL,
.dma_out_enabled = 0,
.dma_in_enabled = 0
#endif
}, /* ttyS0 */
#ifndef CONFIG_SVINTO_SIM
{ .baud = DEF_BAUD,
.ioport = (unsigned char *)R_SERIAL1_CTRL,
.irq = 1U << 16, /* uses DMA 8 and 9 */
.oclrintradr = R_DMA_CH8_CLR_INTR,
.ofirstadr = R_DMA_CH8_FIRST,
.ocmdadr = R_DMA_CH8_CMD,
.ostatusadr = R_DMA_CH8_STATUS,
.iclrintradr = R_DMA_CH9_CLR_INTR,
.ifirstadr = R_DMA_CH9_FIRST,
.icmdadr = R_DMA_CH9_CMD,
.idescradr = R_DMA_CH9_DESCR,
.flags = STD_FLAGS,
.rx_ctrl = DEF_RX,
.tx_ctrl = DEF_TX,
.iseteop = 3,
.dma_owner = dma_ser1,
.io_if = if_serial_1,
#ifdef CONFIG_ETRAX_SERIAL_PORT1
.enabled = 1,
.io_if_description = "ser1",
#ifdef CONFIG_ETRAX_SERIAL_PORT1_DMA8_OUT
.dma_out_enabled = 1,
.dma_out_nbr = SER1_TX_DMA_NBR,
.dma_out_irq_nbr = SER1_DMA_TX_IRQ_NBR,
.dma_out_irq_flags = IRQF_DISABLED,
.dma_out_irq_description = "serial 1 dma tr",
#else
.dma_out_enabled = 0,
.dma_out_nbr = UINT_MAX,
.dma_out_irq_nbr = 0,
.dma_out_irq_flags = 0,
.dma_out_irq_description = NULL,
#endif
#ifdef CONFIG_ETRAX_SERIAL_PORT1_DMA9_IN
.dma_in_enabled = 1,
.dma_in_nbr = SER1_RX_DMA_NBR,
.dma_in_irq_nbr = SER1_DMA_RX_IRQ_NBR,
.dma_in_irq_flags = IRQF_DISABLED,
.dma_in_irq_description = "serial 1 dma rec",
#else
.dma_in_enabled = 0,
.dma_in_enabled = 0,
.dma_in_nbr = UINT_MAX,
.dma_in_irq_nbr = 0,
.dma_in_irq_flags = 0,
.dma_in_irq_description = NULL,
#endif
#else
.enabled = 0,
.io_if_description = NULL,
.dma_in_irq_nbr = 0,
.dma_out_enabled = 0,
.dma_in_enabled = 0
#endif
}, /* ttyS1 */
{ .baud = DEF_BAUD,
.ioport = (unsigned char *)R_SERIAL2_CTRL,
.irq = 1U << 4, /* uses DMA 2 and 3 */
.oclrintradr = R_DMA_CH2_CLR_INTR,
.ofirstadr = R_DMA_CH2_FIRST,
.ocmdadr = R_DMA_CH2_CMD,
.ostatusadr = R_DMA_CH2_STATUS,
.iclrintradr = R_DMA_CH3_CLR_INTR,
.ifirstadr = R_DMA_CH3_FIRST,
.icmdadr = R_DMA_CH3_CMD,
.idescradr = R_DMA_CH3_DESCR,
.flags = STD_FLAGS,
.rx_ctrl = DEF_RX,
.tx_ctrl = DEF_TX,
.iseteop = 0,
.dma_owner = dma_ser2,
.io_if = if_serial_2,
#ifdef CONFIG_ETRAX_SERIAL_PORT2
.enabled = 1,
.io_if_description = "ser2",
#ifdef CONFIG_ETRAX_SERIAL_PORT2_DMA2_OUT
.dma_out_enabled = 1,
.dma_out_nbr = SER2_TX_DMA_NBR,
.dma_out_irq_nbr = SER2_DMA_TX_IRQ_NBR,
.dma_out_irq_flags = IRQF_DISABLED,
.dma_out_irq_description = "serial 2 dma tr",
#else
.dma_out_enabled = 0,
.dma_out_nbr = UINT_MAX,
.dma_out_irq_nbr = 0,
.dma_out_irq_flags = 0,
.dma_out_irq_description = NULL,
#endif
#ifdef CONFIG_ETRAX_SERIAL_PORT2_DMA3_IN
.dma_in_enabled = 1,
.dma_in_nbr = SER2_RX_DMA_NBR,
.dma_in_irq_nbr = SER2_DMA_RX_IRQ_NBR,
.dma_in_irq_flags = IRQF_DISABLED,
.dma_in_irq_description = "serial 2 dma rec",
#else
.dma_in_enabled = 0,
.dma_in_nbr = UINT_MAX,
.dma_in_irq_nbr = 0,
.dma_in_irq_flags = 0,
.dma_in_irq_description = NULL,
#endif
#else
.enabled = 0,
.io_if_description = NULL,
.dma_out_enabled = 0,
.dma_in_enabled = 0
#endif
}, /* ttyS2 */
{ .baud = DEF_BAUD,
.ioport = (unsigned char *)R_SERIAL3_CTRL,
.irq = 1U << 8, /* uses DMA 4 and 5 */
.oclrintradr = R_DMA_CH4_CLR_INTR,
.ofirstadr = R_DMA_CH4_FIRST,
.ocmdadr = R_DMA_CH4_CMD,
.ostatusadr = R_DMA_CH4_STATUS,
.iclrintradr = R_DMA_CH5_CLR_INTR,
.ifirstadr = R_DMA_CH5_FIRST,
.icmdadr = R_DMA_CH5_CMD,
.idescradr = R_DMA_CH5_DESCR,
.flags = STD_FLAGS,
.rx_ctrl = DEF_RX,
.tx_ctrl = DEF_TX,
.iseteop = 1,
.dma_owner = dma_ser3,
.io_if = if_serial_3,
#ifdef CONFIG_ETRAX_SERIAL_PORT3
.enabled = 1,
.io_if_description = "ser3",
#ifdef CONFIG_ETRAX_SERIAL_PORT3_DMA4_OUT
.dma_out_enabled = 1,
.dma_out_nbr = SER3_TX_DMA_NBR,
.dma_out_irq_nbr = SER3_DMA_TX_IRQ_NBR,
.dma_out_irq_flags = IRQF_DISABLED,
.dma_out_irq_description = "serial 3 dma tr",
#else
.dma_out_enabled = 0,
.dma_out_nbr = UINT_MAX,
.dma_out_irq_nbr = 0,
.dma_out_irq_flags = 0,
.dma_out_irq_description = NULL,
#endif
#ifdef CONFIG_ETRAX_SERIAL_PORT3_DMA5_IN
.dma_in_enabled = 1,
.dma_in_nbr = SER3_RX_DMA_NBR,
.dma_in_irq_nbr = SER3_DMA_RX_IRQ_NBR,
.dma_in_irq_flags = IRQF_DISABLED,
.dma_in_irq_description = "serial 3 dma rec",
#else
.dma_in_enabled = 0,
.dma_in_nbr = UINT_MAX,
.dma_in_irq_nbr = 0,
.dma_in_irq_flags = 0,
.dma_in_irq_description = NULL
#endif
#else
.enabled = 0,
.io_if_description = NULL,
.dma_out_enabled = 0,
.dma_in_enabled = 0
#endif
} /* ttyS3 */
#endif
};
#define NR_PORTS (sizeof(rs_table)/sizeof(struct e100_serial))
#ifdef CONFIG_ETRAX_SERIAL_FAST_TIMER
static struct fast_timer fast_timers[NR_PORTS];
#endif
#ifdef CONFIG_ETRAX_SERIAL_PROC_ENTRY
#define PROCSTAT(x) x
struct ser_statistics_type {
int overrun_cnt;
int early_errors_cnt;
int ser_ints_ok_cnt;
int errors_cnt;
unsigned long int processing_flip;
unsigned long processing_flip_still_room;
unsigned long int timeout_flush_cnt;
int rx_dma_ints;
int tx_dma_ints;
int rx_tot;
int tx_tot;
};
static struct ser_statistics_type ser_stat[NR_PORTS];
#else
#define PROCSTAT(x)
#endif /* CONFIG_ETRAX_SERIAL_PROC_ENTRY */
/* RS-485 */
#if defined(CONFIG_ETRAX_RS485)
#ifdef CONFIG_ETRAX_FAST_TIMER
static struct fast_timer fast_timers_rs485[NR_PORTS];
#endif
#if defined(CONFIG_ETRAX_RS485_ON_PA)
static int rs485_pa_bit = CONFIG_ETRAX_RS485_ON_PA_BIT;
#endif
#if defined(CONFIG_ETRAX_RS485_ON_PORT_G)
static int rs485_port_g_bit = CONFIG_ETRAX_RS485_ON_PORT_G_BIT;
#endif
#endif
/* Info and macros needed for each ports extra control/status signals. */
#define E100_STRUCT_PORT(line, pinname) \
((CONFIG_ETRAX_SER##line##_##pinname##_ON_PA_BIT >= 0)? \
(R_PORT_PA_DATA): ( \
(CONFIG_ETRAX_SER##line##_##pinname##_ON_PB_BIT >= 0)? \
(R_PORT_PB_DATA):&dummy_ser[line]))
#define E100_STRUCT_SHADOW(line, pinname) \
((CONFIG_ETRAX_SER##line##_##pinname##_ON_PA_BIT >= 0)? \
(&port_pa_data_shadow): ( \
(CONFIG_ETRAX_SER##line##_##pinname##_ON_PB_BIT >= 0)? \
(&port_pb_data_shadow):&dummy_ser[line]))
#define E100_STRUCT_MASK(line, pinname) \
((CONFIG_ETRAX_SER##line##_##pinname##_ON_PA_BIT >= 0)? \
(1<<CONFIG_ETRAX_SER##line##_##pinname##_ON_PA_BIT): ( \
(CONFIG_ETRAX_SER##line##_##pinname##_ON_PB_BIT >= 0)? \
(1<<CONFIG_ETRAX_SER##line##_##pinname##_ON_PB_BIT):DUMMY_##pinname##_MASK))
#define DUMMY_DTR_MASK 1
#define DUMMY_RI_MASK 2
#define DUMMY_DSR_MASK 4
#define DUMMY_CD_MASK 8
static unsigned char dummy_ser[NR_PORTS] = {0xFF, 0xFF, 0xFF,0xFF};
/* If not all status pins are used or disabled, use mixed mode */
#ifdef CONFIG_ETRAX_SERIAL_PORT0
#define SER0_PA_BITSUM (CONFIG_ETRAX_SER0_DTR_ON_PA_BIT+CONFIG_ETRAX_SER0_RI_ON_PA_BIT+CONFIG_ETRAX_SER0_DSR_ON_PA_BIT+CONFIG_ETRAX_SER0_CD_ON_PA_BIT)
#if SER0_PA_BITSUM != -4
# if CONFIG_ETRAX_SER0_DTR_ON_PA_BIT == -1
# ifndef CONFIG_ETRAX_SER0_DTR_RI_DSR_CD_MIXED
# define CONFIG_ETRAX_SER0_DTR_RI_DSR_CD_MIXED 1
# endif
# endif
# if CONFIG_ETRAX_SER0_RI_ON_PA_BIT == -1
# ifndef CONFIG_ETRAX_SER0_DTR_RI_DSR_CD_MIXED
# define CONFIG_ETRAX_SER0_DTR_RI_DSR_CD_MIXED 1
# endif
# endif
# if CONFIG_ETRAX_SER0_DSR_ON_PA_BIT == -1
# ifndef CONFIG_ETRAX_SER0_DTR_RI_DSR_CD_MIXED
# define CONFIG_ETRAX_SER0_DTR_RI_DSR_CD_MIXED 1
# endif
# endif
# if CONFIG_ETRAX_SER0_CD_ON_PA_BIT == -1
# ifndef CONFIG_ETRAX_SER0_DTR_RI_DSR_CD_MIXED
# define CONFIG_ETRAX_SER0_DTR_RI_DSR_CD_MIXED 1
# endif
# endif
#endif
#define SER0_PB_BITSUM (CONFIG_ETRAX_SER0_DTR_ON_PB_BIT+CONFIG_ETRAX_SER0_RI_ON_PB_BIT+CONFIG_ETRAX_SER0_DSR_ON_PB_BIT+CONFIG_ETRAX_SER0_CD_ON_PB_BIT)
#if SER0_PB_BITSUM != -4
# if CONFIG_ETRAX_SER0_DTR_ON_PB_BIT == -1
# ifndef CONFIG_ETRAX_SER0_DTR_RI_DSR_CD_MIXED
# define CONFIG_ETRAX_SER0_DTR_RI_DSR_CD_MIXED 1
# endif
# endif
# if CONFIG_ETRAX_SER0_RI_ON_PB_BIT == -1
# ifndef CONFIG_ETRAX_SER0_DTR_RI_DSR_CD_MIXED
# define CONFIG_ETRAX_SER0_DTR_RI_DSR_CD_MIXED 1
# endif
# endif
# if CONFIG_ETRAX_SER0_DSR_ON_PB_BIT == -1
# ifndef CONFIG_ETRAX_SER0_DTR_RI_DSR_CD_MIXED
# define CONFIG_ETRAX_SER0_DTR_RI_DSR_CD_MIXED 1
# endif
# endif
# if CONFIG_ETRAX_SER0_CD_ON_PB_BIT == -1
# ifndef CONFIG_ETRAX_SER0_DTR_RI_DSR_CD_MIXED
# define CONFIG_ETRAX_SER0_DTR_RI_DSR_CD_MIXED 1
# endif
# endif
#endif
#endif /* PORT0 */
#ifdef CONFIG_ETRAX_SERIAL_PORT1
#define SER1_PA_BITSUM (CONFIG_ETRAX_SER1_DTR_ON_PA_BIT+CONFIG_ETRAX_SER1_RI_ON_PA_BIT+CONFIG_ETRAX_SER1_DSR_ON_PA_BIT+CONFIG_ETRAX_SER1_CD_ON_PA_BIT)
#if SER1_PA_BITSUM != -4
# if CONFIG_ETRAX_SER1_DTR_ON_PA_BIT == -1
# ifndef CONFIG_ETRAX_SER1_DTR_RI_DSR_CD_MIXED
# define CONFIG_ETRAX_SER1_DTR_RI_DSR_CD_MIXED 1
# endif
# endif
# if CONFIG_ETRAX_SER1_RI_ON_PA_BIT == -1
# ifndef CONFIG_ETRAX_SER1_DTR_RI_DSR_CD_MIXED
# define CONFIG_ETRAX_SER1_DTR_RI_DSR_CD_MIXED 1
# endif
# endif
# if CONFIG_ETRAX_SER1_DSR_ON_PA_BIT == -1
# ifndef CONFIG_ETRAX_SER1_DTR_RI_DSR_CD_MIXED
# define CONFIG_ETRAX_SER1_DTR_RI_DSR_CD_MIXED 1
# endif
# endif
# if CONFIG_ETRAX_SER1_CD_ON_PA_BIT == -1
# ifndef CONFIG_ETRAX_SER1_DTR_RI_DSR_CD_MIXED
# define CONFIG_ETRAX_SER1_DTR_RI_DSR_CD_MIXED 1
# endif
# endif
#endif
#define SER1_PB_BITSUM (CONFIG_ETRAX_SER1_DTR_ON_PB_BIT+CONFIG_ETRAX_SER1_RI_ON_PB_BIT+CONFIG_ETRAX_SER1_DSR_ON_PB_BIT+CONFIG_ETRAX_SER1_CD_ON_PB_BIT)
#if SER1_PB_BITSUM != -4
# if CONFIG_ETRAX_SER1_DTR_ON_PB_BIT == -1
# ifndef CONFIG_ETRAX_SER1_DTR_RI_DSR_CD_MIXED
# define CONFIG_ETRAX_SER1_DTR_RI_DSR_CD_MIXED 1
# endif
# endif
# if CONFIG_ETRAX_SER1_RI_ON_PB_BIT == -1
# ifndef CONFIG_ETRAX_SER1_DTR_RI_DSR_CD_MIXED
# define CONFIG_ETRAX_SER1_DTR_RI_DSR_CD_MIXED 1
# endif
# endif
# if CONFIG_ETRAX_SER1_DSR_ON_PB_BIT == -1
# ifndef CONFIG_ETRAX_SER1_DTR_RI_DSR_CD_MIXED
# define CONFIG_ETRAX_SER1_DTR_RI_DSR_CD_MIXED 1
# endif
# endif
# if CONFIG_ETRAX_SER1_CD_ON_PB_BIT == -1
# ifndef CONFIG_ETRAX_SER1_DTR_RI_DSR_CD_MIXED
# define CONFIG_ETRAX_SER1_DTR_RI_DSR_CD_MIXED 1
# endif
# endif
#endif
#endif /* PORT1 */
#ifdef CONFIG_ETRAX_SERIAL_PORT2
#define SER2_PA_BITSUM (CONFIG_ETRAX_SER2_DTR_ON_PA_BIT+CONFIG_ETRAX_SER2_RI_ON_PA_BIT+CONFIG_ETRAX_SER2_DSR_ON_PA_BIT+CONFIG_ETRAX_SER2_CD_ON_PA_BIT)
#if SER2_PA_BITSUM != -4
# if CONFIG_ETRAX_SER2_DTR_ON_PA_BIT == -1
# ifndef CONFIG_ETRAX_SER2_DTR_RI_DSR_CD_MIXED
# define CONFIG_ETRAX_SER2_DTR_RI_DSR_CD_MIXED 1
# endif
# endif
# if CONFIG_ETRAX_SER2_RI_ON_PA_BIT == -1
# ifndef CONFIG_ETRAX_SER2_DTR_RI_DSR_CD_MIXED
# define CONFIG_ETRAX_SER2_DTR_RI_DSR_CD_MIXED 1
# endif
# endif
# if CONFIG_ETRAX_SER2_DSR_ON_PA_BIT == -1
# ifndef CONFIG_ETRAX_SER2_DTR_RI_DSR_CD_MIXED
# define CONFIG_ETRAX_SER2_DTR_RI_DSR_CD_MIXED 1
# endif
# endif
# if CONFIG_ETRAX_SER2_CD_ON_PA_BIT == -1
# ifndef CONFIG_ETRAX_SER2_DTR_RI_DSR_CD_MIXED
# define CONFIG_ETRAX_SER2_DTR_RI_DSR_CD_MIXED 1
# endif
# endif
#endif
#define SER2_PB_BITSUM (CONFIG_ETRAX_SER2_DTR_ON_PB_BIT+CONFIG_ETRAX_SER2_RI_ON_PB_BIT+CONFIG_ETRAX_SER2_DSR_ON_PB_BIT+CONFIG_ETRAX_SER2_CD_ON_PB_BIT)
#if SER2_PB_BITSUM != -4
# if CONFIG_ETRAX_SER2_DTR_ON_PB_BIT == -1
# ifndef CONFIG_ETRAX_SER2_DTR_RI_DSR_CD_MIXED
# define CONFIG_ETRAX_SER2_DTR_RI_DSR_CD_MIXED 1
# endif
# endif
# if CONFIG_ETRAX_SER2_RI_ON_PB_BIT == -1
# ifndef CONFIG_ETRAX_SER2_DTR_RI_DSR_CD_MIXED
# define CONFIG_ETRAX_SER2_DTR_RI_DSR_CD_MIXED 1
# endif
# endif
# if CONFIG_ETRAX_SER2_DSR_ON_PB_BIT == -1
# ifndef CONFIG_ETRAX_SER2_DTR_RI_DSR_CD_MIXED
# define CONFIG_ETRAX_SER2_DTR_RI_DSR_CD_MIXED 1
# endif
# endif
# if CONFIG_ETRAX_SER2_CD_ON_PB_BIT == -1
# ifndef CONFIG_ETRAX_SER2_DTR_RI_DSR_CD_MIXED
# define CONFIG_ETRAX_SER2_DTR_RI_DSR_CD_MIXED 1
# endif
# endif
#endif
#endif /* PORT2 */
#ifdef CONFIG_ETRAX_SERIAL_PORT3
#define SER3_PA_BITSUM (CONFIG_ETRAX_SER3_DTR_ON_PA_BIT+CONFIG_ETRAX_SER3_RI_ON_PA_BIT+CONFIG_ETRAX_SER3_DSR_ON_PA_BIT+CONFIG_ETRAX_SER3_CD_ON_PA_BIT)
#if SER3_PA_BITSUM != -4
# if CONFIG_ETRAX_SER3_DTR_ON_PA_BIT == -1
# ifndef CONFIG_ETRAX_SER3_DTR_RI_DSR_CD_MIXED
# define CONFIG_ETRAX_SER3_DTR_RI_DSR_CD_MIXED 1
# endif
# endif
# if CONFIG_ETRAX_SER3_RI_ON_PA_BIT == -1
# ifndef CONFIG_ETRAX_SER3_DTR_RI_DSR_CD_MIXED
# define CONFIG_ETRAX_SER3_DTR_RI_DSR_CD_MIXED 1
# endif
# endif
# if CONFIG_ETRAX_SER3_DSR_ON_PA_BIT == -1
# ifndef CONFIG_ETRAX_SER3_DTR_RI_DSR_CD_MIXED
# define CONFIG_ETRAX_SER3_DTR_RI_DSR_CD_MIXED 1
# endif
# endif
# if CONFIG_ETRAX_SER3_CD_ON_PA_BIT == -1
# ifndef CONFIG_ETRAX_SER3_DTR_RI_DSR_CD_MIXED
# define CONFIG_ETRAX_SER3_DTR_RI_DSR_CD_MIXED 1
# endif
# endif
#endif
#define SER3_PB_BITSUM (CONFIG_ETRAX_SER3_DTR_ON_PB_BIT+CONFIG_ETRAX_SER3_RI_ON_PB_BIT+CONFIG_ETRAX_SER3_DSR_ON_PB_BIT+CONFIG_ETRAX_SER3_CD_ON_PB_BIT)
#if SER3_PB_BITSUM != -4
# if CONFIG_ETRAX_SER3_DTR_ON_PB_BIT == -1
# ifndef CONFIG_ETRAX_SER3_DTR_RI_DSR_CD_MIXED
# define CONFIG_ETRAX_SER3_DTR_RI_DSR_CD_MIXED 1
# endif
# endif
# if CONFIG_ETRAX_SER3_RI_ON_PB_BIT == -1
# ifndef CONFIG_ETRAX_SER3_DTR_RI_DSR_CD_MIXED
# define CONFIG_ETRAX_SER3_DTR_RI_DSR_CD_MIXED 1
# endif
# endif
# if CONFIG_ETRAX_SER3_DSR_ON_PB_BIT == -1
# ifndef CONFIG_ETRAX_SER3_DTR_RI_DSR_CD_MIXED
# define CONFIG_ETRAX_SER3_DTR_RI_DSR_CD_MIXED 1
# endif
# endif
# if CONFIG_ETRAX_SER3_CD_ON_PB_BIT == -1
# ifndef CONFIG_ETRAX_SER3_DTR_RI_DSR_CD_MIXED
# define CONFIG_ETRAX_SER3_DTR_RI_DSR_CD_MIXED 1
# endif
# endif
#endif
#endif /* PORT3 */
#if defined(CONFIG_ETRAX_SER0_DTR_RI_DSR_CD_MIXED) || \
defined(CONFIG_ETRAX_SER1_DTR_RI_DSR_CD_MIXED) || \
defined(CONFIG_ETRAX_SER2_DTR_RI_DSR_CD_MIXED) || \
defined(CONFIG_ETRAX_SER3_DTR_RI_DSR_CD_MIXED)
#define CONFIG_ETRAX_SERX_DTR_RI_DSR_CD_MIXED
#endif
#ifdef CONFIG_ETRAX_SERX_DTR_RI_DSR_CD_MIXED
/* The pins can be mixed on PA and PB */
#define CONTROL_PINS_PORT_NOT_USED(line) \
&dummy_ser[line], &dummy_ser[line], \
&dummy_ser[line], &dummy_ser[line], \
&dummy_ser[line], &dummy_ser[line], \
&dummy_ser[line], &dummy_ser[line], \
DUMMY_DTR_MASK, DUMMY_RI_MASK, DUMMY_DSR_MASK, DUMMY_CD_MASK
struct control_pins
{
volatile unsigned char *dtr_port;
unsigned char *dtr_shadow;
volatile unsigned char *ri_port;
unsigned char *ri_shadow;
volatile unsigned char *dsr_port;
unsigned char *dsr_shadow;
volatile unsigned char *cd_port;
unsigned char *cd_shadow;
unsigned char dtr_mask;
unsigned char ri_mask;
unsigned char dsr_mask;
unsigned char cd_mask;
};
static const struct control_pins e100_modem_pins[NR_PORTS] =
{
/* Ser 0 */
{
#ifdef CONFIG_ETRAX_SERIAL_PORT0
E100_STRUCT_PORT(0,DTR), E100_STRUCT_SHADOW(0,DTR),
E100_STRUCT_PORT(0,RI), E100_STRUCT_SHADOW(0,RI),
E100_STRUCT_PORT(0,DSR), E100_STRUCT_SHADOW(0,DSR),
E100_STRUCT_PORT(0,CD), E100_STRUCT_SHADOW(0,CD),
E100_STRUCT_MASK(0,DTR),
E100_STRUCT_MASK(0,RI),
E100_STRUCT_MASK(0,DSR),
E100_STRUCT_MASK(0,CD)
#else
CONTROL_PINS_PORT_NOT_USED(0)
#endif
},
/* Ser 1 */
{
#ifdef CONFIG_ETRAX_SERIAL_PORT1
E100_STRUCT_PORT(1,DTR), E100_STRUCT_SHADOW(1,DTR),
E100_STRUCT_PORT(1,RI), E100_STRUCT_SHADOW(1,RI),
E100_STRUCT_PORT(1,DSR), E100_STRUCT_SHADOW(1,DSR),
E100_STRUCT_PORT(1,CD), E100_STRUCT_SHADOW(1,CD),
E100_STRUCT_MASK(1,DTR),
E100_STRUCT_MASK(1,RI),
E100_STRUCT_MASK(1,DSR),
E100_STRUCT_MASK(1,CD)
#else
CONTROL_PINS_PORT_NOT_USED(1)
#endif
},
/* Ser 2 */
{
#ifdef CONFIG_ETRAX_SERIAL_PORT2
E100_STRUCT_PORT(2,DTR), E100_STRUCT_SHADOW(2,DTR),
E100_STRUCT_PORT(2,RI), E100_STRUCT_SHADOW(2,RI),
E100_STRUCT_PORT(2,DSR), E100_STRUCT_SHADOW(2,DSR),
E100_STRUCT_PORT(2,CD), E100_STRUCT_SHADOW(2,CD),
E100_STRUCT_MASK(2,DTR),
E100_STRUCT_MASK(2,RI),
E100_STRUCT_MASK(2,DSR),
E100_STRUCT_MASK(2,CD)
#else
CONTROL_PINS_PORT_NOT_USED(2)
#endif
},
/* Ser 3 */
{
#ifdef CONFIG_ETRAX_SERIAL_PORT3
E100_STRUCT_PORT(3,DTR), E100_STRUCT_SHADOW(3,DTR),
E100_STRUCT_PORT(3,RI), E100_STRUCT_SHADOW(3,RI),
E100_STRUCT_PORT(3,DSR), E100_STRUCT_SHADOW(3,DSR),
E100_STRUCT_PORT(3,CD), E100_STRUCT_SHADOW(3,CD),
E100_STRUCT_MASK(3,DTR),
E100_STRUCT_MASK(3,RI),
E100_STRUCT_MASK(3,DSR),
E100_STRUCT_MASK(3,CD)
#else
CONTROL_PINS_PORT_NOT_USED(3)
#endif
}
};
#else /* CONFIG_ETRAX_SERX_DTR_RI_DSR_CD_MIXED */
/* All pins are on either PA or PB for each serial port */
#define CONTROL_PINS_PORT_NOT_USED(line) \
&dummy_ser[line], &dummy_ser[line], \
DUMMY_DTR_MASK, DUMMY_RI_MASK, DUMMY_DSR_MASK, DUMMY_CD_MASK
struct control_pins
{
volatile unsigned char *port;
unsigned char *shadow;
unsigned char dtr_mask;
unsigned char ri_mask;
unsigned char dsr_mask;
unsigned char cd_mask;
};
#define dtr_port port
#define dtr_shadow shadow
#define ri_port port
#define ri_shadow shadow
#define dsr_port port
#define dsr_shadow shadow
#define cd_port port
#define cd_shadow shadow
static const struct control_pins e100_modem_pins[NR_PORTS] =
{
/* Ser 0 */
{
#ifdef CONFIG_ETRAX_SERIAL_PORT0
E100_STRUCT_PORT(0,DTR), E100_STRUCT_SHADOW(0,DTR),
E100_STRUCT_MASK(0,DTR),
E100_STRUCT_MASK(0,RI),
E100_STRUCT_MASK(0,DSR),
E100_STRUCT_MASK(0,CD)
#else
CONTROL_PINS_PORT_NOT_USED(0)
#endif
},
/* Ser 1 */
{
#ifdef CONFIG_ETRAX_SERIAL_PORT1
E100_STRUCT_PORT(1,DTR), E100_STRUCT_SHADOW(1,DTR),
E100_STRUCT_MASK(1,DTR),
E100_STRUCT_MASK(1,RI),
E100_STRUCT_MASK(1,DSR),
E100_STRUCT_MASK(1,CD)
#else
CONTROL_PINS_PORT_NOT_USED(1)
#endif
},
/* Ser 2 */
{
#ifdef CONFIG_ETRAX_SERIAL_PORT2
E100_STRUCT_PORT(2,DTR), E100_STRUCT_SHADOW(2,DTR),
E100_STRUCT_MASK(2,DTR),
E100_STRUCT_MASK(2,RI),
E100_STRUCT_MASK(2,DSR),
E100_STRUCT_MASK(2,CD)
#else
CONTROL_PINS_PORT_NOT_USED(2)
#endif
},
/* Ser 3 */
{
#ifdef CONFIG_ETRAX_SERIAL_PORT3
E100_STRUCT_PORT(3,DTR), E100_STRUCT_SHADOW(3,DTR),
E100_STRUCT_MASK(3,DTR),
E100_STRUCT_MASK(3,RI),
E100_STRUCT_MASK(3,DSR),
E100_STRUCT_MASK(3,CD)
#else
CONTROL_PINS_PORT_NOT_USED(3)
#endif
}
};
#endif /* !CONFIG_ETRAX_SERX_DTR_RI_DSR_CD_MIXED */
#define E100_RTS_MASK 0x20
#define E100_CTS_MASK 0x40
/* All serial port signals are active low:
* active = 0 -> 3.3V to RS-232 driver -> -12V on RS-232 level
* inactive = 1 -> 0V to RS-232 driver -> +12V on RS-232 level
*
* These macros returns the pin value: 0=0V, >=1 = 3.3V on ETRAX chip
*/
/* Output */
#define E100_RTS_GET(info) ((info)->rx_ctrl & E100_RTS_MASK)
/* Input */
#define E100_CTS_GET(info) ((info)->ioport[REG_STATUS] & E100_CTS_MASK)
/* These are typically PA or PB and 0 means 0V, 1 means 3.3V */
/* Is an output */
#define E100_DTR_GET(info) ((*e100_modem_pins[(info)->line].dtr_shadow) & e100_modem_pins[(info)->line].dtr_mask)
/* Normally inputs */
#define E100_RI_GET(info) ((*e100_modem_pins[(info)->line].ri_port) & e100_modem_pins[(info)->line].ri_mask)
#define E100_CD_GET(info) ((*e100_modem_pins[(info)->line].cd_port) & e100_modem_pins[(info)->line].cd_mask)
/* Input */
#define E100_DSR_GET(info) ((*e100_modem_pins[(info)->line].dsr_port) & e100_modem_pins[(info)->line].dsr_mask)
/*
* tmp_buf is used as a temporary buffer by serial_write. We need to
* lock it in case the memcpy_fromfs blocks while swapping in a page,
* and some other program tries to do a serial write at the same time.
* Since the lock will only come under contention when the system is
* swapping and available memory is low, it makes sense to share one
* buffer across all the serial ports, since it significantly saves
* memory if large numbers of serial ports are open.
*/
static unsigned char *tmp_buf;
static DEFINE_MUTEX(tmp_buf_mutex);
/* Calculate the chartime depending on baudrate, numbor of bits etc. */
static void update_char_time(struct e100_serial * info)
{
tcflag_t cflags = info->port.tty->termios->c_cflag;
int bits;
/* calc. number of bits / data byte */
/* databits + startbit and 1 stopbit */
if ((cflags & CSIZE) == CS7)
bits = 9;
else
bits = 10;
if (cflags & CSTOPB) /* 2 stopbits ? */
bits++;
if (cflags & PARENB) /* parity bit ? */
bits++;
/* calc timeout */
info->char_time_usec = ((bits * 1000000) / info->baud) + 1;
info->flush_time_usec = 4*info->char_time_usec;
if (info->flush_time_usec < MIN_FLUSH_TIME_USEC)
info->flush_time_usec = MIN_FLUSH_TIME_USEC;
}
/*
* This function maps from the Bxxxx defines in asm/termbits.h into real
* baud rates.
*/