synclinkmp.c

来自「Linux Kernel 2.6.9 for OMAP1710」· C语言 代码 · 共 2,458 行 · 第 1/5 页

	SLMP_INFO *info = (SLMP_INFO *)tty->driver_data;
	unsigned long flags;

	if (debug_level >= DEBUG_LEVEL_INFO)
		printk("%s(%d):%s write() count=%d\n",
		       __FILE__,__LINE__,info->device_name,count);

	if (sanity_check(info, tty->name, "write"))
		goto cleanup;

	if (!tty || !info->tx_buf)
		goto cleanup;

	if (info->params.mode == MGSL_MODE_HDLC) {
		if (count > info->max_frame_size) {
			ret = -EIO;
			goto cleanup;
		}
		if (info->tx_active)
			goto cleanup;
		if (info->tx_count) {
			/* send accumulated data from send_char() calls */
			/* as frame and wait before accepting more data. */
			tx_load_dma_buffer(info, info->tx_buf, info->tx_count);
			goto start;
		}
		if (!from_user) {
			ret = info->tx_count = count;
			tx_load_dma_buffer(info, buf, count);
			goto start;
		}
	}

	for (;;) {
		c = min_t(int, count,
			min(info->max_frame_size - info->tx_count - 1,
			    info->max_frame_size - info->tx_put));
		if (c <= 0)
			break;
			
		if (from_user) {
			COPY_FROM_USER(err, info->tx_buf + info->tx_put, buf, c);
			if (err) {
				if (!ret)
					ret = -EFAULT;
				break;
			}
		} else
			memcpy(info->tx_buf + info->tx_put, buf, c);

		spin_lock_irqsave(&info->lock,flags);
		info->tx_put += c;
		if (info->tx_put >= info->max_frame_size)
			info->tx_put -= info->max_frame_size;
		info->tx_count += c;
		spin_unlock_irqrestore(&info->lock,flags);

		buf += c;
		count -= c;
		ret += c;
	}

	if (info->params.mode == MGSL_MODE_HDLC) {
		if (count) {
			ret = info->tx_count = 0;
			goto cleanup;
		}
		tx_load_dma_buffer(info, info->tx_buf, info->tx_count);
	}
start:
 	if (info->tx_count && !tty->stopped && !tty->hw_stopped) {
		spin_lock_irqsave(&info->lock,flags);
		if (!info->tx_active)
		 	tx_start(info);
		spin_unlock_irqrestore(&info->lock,flags);
 	}

cleanup:
	if (debug_level >= DEBUG_LEVEL_INFO)
		printk( "%s(%d):%s write() returning=%d\n",
			__FILE__,__LINE__,info->device_name,ret);
	return ret;
}

/* Add a character to the transmit buffer.
 */
static void put_char(struct tty_struct *tty, unsigned char ch)
{
	SLMP_INFO *info = (SLMP_INFO *)tty->driver_data;
	unsigned long flags;

	if ( debug_level >= DEBUG_LEVEL_INFO ) {
		printk( "%s(%d):%s put_char(%d)\n",
			__FILE__,__LINE__,info->device_name,ch);
	}

	if (sanity_check(info, tty->name, "put_char"))
		return;

	if (!tty || !info->tx_buf)
		return;

	spin_lock_irqsave(&info->lock,flags);

	if ( (info->params.mode != MGSL_MODE_HDLC) ||
	     !info->tx_active ) {

		if (info->tx_count < info->max_frame_size - 1) {
			info->tx_buf[info->tx_put++] = ch;
			if (info->tx_put >= info->max_frame_size)
				info->tx_put -= info->max_frame_size;
			info->tx_count++;
		}
	}

	spin_unlock_irqrestore(&info->lock,flags);
}

/* Send a high-priority XON/XOFF character
 */
static void send_xchar(struct tty_struct *tty, char ch)
{
	SLMP_INFO *info = (SLMP_INFO *)tty->driver_data;
	unsigned long flags;

	if (debug_level >= DEBUG_LEVEL_INFO)
		printk("%s(%d):%s send_xchar(%d)\n",
			 __FILE__,__LINE__, info->device_name, ch );

	if (sanity_check(info, tty->name, "send_xchar"))
		return;

	info->x_char = ch;
	if (ch) {
		/* Make sure transmit interrupts are on */
		spin_lock_irqsave(&info->lock,flags);
		if (!info->tx_enabled)
		 	tx_start(info);
		spin_unlock_irqrestore(&info->lock,flags);
	}
}

/* Wait until the transmitter is empty.
 */
static void wait_until_sent(struct tty_struct *tty, int timeout)
{
	SLMP_INFO * info = (SLMP_INFO *)tty->driver_data;
	unsigned long orig_jiffies, char_time;

	if (!info )
		return;

	if (debug_level >= DEBUG_LEVEL_INFO)
		printk("%s(%d):%s wait_until_sent() entry\n",
			 __FILE__,__LINE__, info->device_name );

	if (sanity_check(info, tty->name, "wait_until_sent"))
		return;

	if (!(info->flags & ASYNC_INITIALIZED))
		goto exit;

	orig_jiffies = jiffies;

	/* Set check interval to 1/5 of estimated time to
	 * send a character, and make it at least 1. The check
	 * interval should also be less than the timeout.
	 * Note: use tight timings here to satisfy the NIST-PCTS.
	 */

	if ( info->params.data_rate ) {
	       	char_time = info->timeout/(32 * 5);
		if (!char_time)
			char_time++;
	} else
		char_time = 1;

	if (timeout)
		char_time = min_t(unsigned long, char_time, timeout);

	if ( info->params.mode == MGSL_MODE_HDLC ) {
		while (info->tx_active) {
			set_current_state(TASK_INTERRUPTIBLE);
			schedule_timeout(char_time);
			if (signal_pending(current))
				break;
			if (timeout && time_after(jiffies, orig_jiffies + timeout))
				break;
		}
	} else {
		//TODO: determine if there is something similar to USC16C32
		// 	TXSTATUS_ALL_SENT status
		while ( info->tx_active && info->tx_enabled) {
			set_current_state(TASK_INTERRUPTIBLE);
			schedule_timeout(char_time);
			if (signal_pending(current))
				break;
			if (timeout && time_after(jiffies, orig_jiffies + timeout))
				break;
		}
	}

exit:
	if (debug_level >= DEBUG_LEVEL_INFO)
		printk("%s(%d):%s wait_until_sent() exit\n",
			 __FILE__,__LINE__, info->device_name );
}

/* Return the count of free bytes in transmit buffer
 */
static int write_room(struct tty_struct *tty)
{
	SLMP_INFO *info = (SLMP_INFO *)tty->driver_data;
	int ret;

	if (sanity_check(info, tty->name, "write_room"))
		return 0;

	if (info->params.mode == MGSL_MODE_HDLC) {
		ret = (info->tx_active) ? 0 : HDLC_MAX_FRAME_SIZE;
	} else {
		ret = info->max_frame_size - info->tx_count - 1;
		if (ret < 0)
			ret = 0;
	}

	if (debug_level >= DEBUG_LEVEL_INFO)
		printk("%s(%d):%s write_room()=%d\n",
		       __FILE__, __LINE__, info->device_name, ret);

	return ret;
}

/* enable transmitter and send remaining buffered characters
 */
static void flush_chars(struct tty_struct *tty)
{
	SLMP_INFO *info = (SLMP_INFO *)tty->driver_data;
	unsigned long flags;

	if ( debug_level >= DEBUG_LEVEL_INFO )
		printk( "%s(%d):%s flush_chars() entry tx_count=%d\n",
			__FILE__,__LINE__,info->device_name,info->tx_count);

	if (sanity_check(info, tty->name, "flush_chars"))
		return;

	if (info->tx_count <= 0 || tty->stopped || tty->hw_stopped ||
	    !info->tx_buf)
		return;

	if ( debug_level >= DEBUG_LEVEL_INFO )
		printk( "%s(%d):%s flush_chars() entry, starting transmitter\n",
			__FILE__,__LINE__,info->device_name );

	spin_lock_irqsave(&info->lock,flags);

	if (!info->tx_active) {
		if ( (info->params.mode == MGSL_MODE_HDLC) &&
			info->tx_count ) {
			/* operating in synchronous (frame oriented) mode */
			/* copy data from circular tx_buf to */
			/* transmit DMA buffer. */
			tx_load_dma_buffer(info,
				 info->tx_buf,info->tx_count);
		}
	 	tx_start(info);
	}

	spin_unlock_irqrestore(&info->lock,flags);
}

/* Discard all data in the send buffer
 */
static void flush_buffer(struct tty_struct *tty)
{
	SLMP_INFO *info = (SLMP_INFO *)tty->driver_data;
	unsigned long flags;

	if (debug_level >= DEBUG_LEVEL_INFO)
		printk("%s(%d):%s flush_buffer() entry\n",
			 __FILE__,__LINE__, info->device_name );

	if (sanity_check(info, tty->name, "flush_buffer"))
		return;

	spin_lock_irqsave(&info->lock,flags);
	info->tx_count = info->tx_put = info->tx_get = 0;
	del_timer(&info->tx_timer);
	spin_unlock_irqrestore(&info->lock,flags);

	wake_up_interruptible(&tty->write_wait);
	tty_wakeup(tty);
}

/* throttle (stop) transmitter
 */
static void tx_hold(struct tty_struct *tty)
{
	SLMP_INFO *info = (SLMP_INFO *)tty->driver_data;
	unsigned long flags;

	if (sanity_check(info, tty->name, "tx_hold"))
		return;

	if ( debug_level >= DEBUG_LEVEL_INFO )
		printk("%s(%d):%s tx_hold()\n",
			__FILE__,__LINE__,info->device_name);

	spin_lock_irqsave(&info->lock,flags);
	if (info->tx_enabled)
	 	tx_stop(info);
	spin_unlock_irqrestore(&info->lock,flags);
}

/* release (start) transmitter
 */
static void tx_release(struct tty_struct *tty)
{
	SLMP_INFO *info = (SLMP_INFO *)tty->driver_data;
	unsigned long flags;

	if (sanity_check(info, tty->name, "tx_release"))
		return;

	if ( debug_level >= DEBUG_LEVEL_INFO )
		printk("%s(%d):%s tx_release()\n",
			__FILE__,__LINE__,info->device_name);

	spin_lock_irqsave(&info->lock,flags);
	if (!info->tx_enabled)
	 	tx_start(info);
	spin_unlock_irqrestore(&info->lock,flags);
}

/* Service an IOCTL request
 *
 * Arguments:
 *
 * 	tty	pointer to tty instance data
 * 	file	pointer to associated file object for device
 * 	cmd	IOCTL command code
 * 	arg	command argument/context
 *
 * Return Value:	0 if success, otherwise error code
 */
static int ioctl(struct tty_struct *tty, struct file *file,
		 unsigned int cmd, unsigned long arg)
{
	SLMP_INFO *info = (SLMP_INFO *)tty->driver_data;
	int error;
	struct mgsl_icount cnow;	/* kernel counter temps */
	struct serial_icounter_struct __user *p_cuser;	/* user space */
	unsigned long flags;
	void __user *argp = (void __user *)arg;

	if (debug_level >= DEBUG_LEVEL_INFO)
		printk("%s(%d):%s ioctl() cmd=%08X\n", __FILE__,__LINE__,
			info->device_name, cmd );

	if (sanity_check(info, tty->name, "ioctl"))
		return -ENODEV;

	if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
	    (cmd != TIOCMIWAIT) && (cmd != TIOCGICOUNT)) {
		if (tty->flags & (1 << TTY_IO_ERROR))
		    return -EIO;
	}

	switch (cmd) {
	case MGSL_IOCGPARAMS:
		return get_params(info, argp);
	case MGSL_IOCSPARAMS:
		return set_params(info, argp);
	case MGSL_IOCGTXIDLE:
		return get_txidle(info, argp);
	case MGSL_IOCSTXIDLE:
		return set_txidle(info, (int)arg);
	case MGSL_IOCTXENABLE:
		return tx_enable(info, (int)arg);
	case MGSL_IOCRXENABLE:
		return rx_enable(info, (int)arg);
	case MGSL_IOCTXABORT:
		return tx_abort(info);
	case MGSL_IOCGSTATS:
		return get_stats(info, argp);
	case MGSL_IOCWAITEVENT:
		return wait_mgsl_event(info, argp);
	case MGSL_IOCLOOPTXDONE:
		return 0; // TODO: Not supported, need to document
		/* Wait for modem input (DCD,RI,DSR,CTS) change
		 * as specified by mask in arg (TIOCM_RNG/DSR/CD/CTS)
		 */
	case TIOCMIWAIT:
		return modem_input_wait(info,(int)arg);
		
		/*
		 * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
		 * Return: write counters to the user passed counter struct
		 * NB: both 1->0 and 0->1 transitions are counted except for
		 *     RI where only 0->1 is counted.
		 */
	case TIOCGICOUNT:
		spin_lock_irqsave(&info->lock,flags);
		cnow = info->icount;
		spin_unlock_irqrestore(&info->lock,flags);
		p_cuser = argp;
		PUT_USER(error,cnow.cts, &p_cuser->cts);
		if (error) return error;
		PUT_USER(error,cnow.dsr, &p_cuser->dsr);
		if (error) return error;
		PUT_USER(error,cnow.rng, &p_cuser->rng);
		if (error) return error;
		PUT_USER(error,cnow.dcd, &p_cuser->dcd);
		if (error) return error;
		PUT_USER(error,cnow.rx, &p_cuser->rx);
		if (error) return error;
		PUT_USER(error,cnow.tx, &p_cuser->tx);
		if (error) return error;
		PUT_USER(error,cnow.frame, &p_cuser->frame);
		if (error) return error;
		PUT_USER(error,cnow.overrun, &p_cuser->overrun);
		if (error) return error;
		PUT_USER(error,cnow.parity, &p_cuser->parity);
		if (error) return error;
		PUT_USER(error,cnow.brk, &p_cuser->brk);
		if (error) return error;
		PUT_USER(error,cnow.buf_overrun, &p_cuser->buf_overrun);
		if (error) return error;
		return 0;
	default:
		return -ENOIOCTLCMD;
	}
	return 0;
}

/*
 * /proc fs routines....
 */

static inline int line_info(char *buf, SLMP_INFO *info)
{
	char	stat_buf[30];
	int	ret;
	unsigned long flags;

	ret = sprintf(buf, "%s: SCABase=%08x Mem=%08X StatusControl=%08x LCR=%08X\n"
		       "\tIRQ=%d MaxFrameSize=%u\n",
		info->device_name,
		info->phys_sca_base,
		info->phys_memory_base,
		info->phys_statctrl_base,
		info->phys_lcr_base,
		info->irq_level,
		info->max_frame_size );

	/* output current serial signal states */
	spin_lock_irqsave(&info->lock,flags);
 	get_signals(info);
	spin_unlock_irqrestore(&info->lock,flags);

	stat_buf[0] = 0;
	stat_buf[1] = 0;
	if (info->serial_signals & SerialSignal_RTS)
		strcat(stat_buf, "|RTS");
	if (info->serial_signals & SerialSignal_CTS)
		strcat(stat_buf, "|CTS");
	if (info->serial_signals & SerialSignal_DTR)
		strcat(stat_buf, "|DTR");
	if (info->serial_signals & SerialSignal_DSR)
		strcat(stat_buf, "|DSR");
	if (info->serial_signals & SerialSignal_DCD)
		strcat(stat_buf, "|CD");
	if (info->serial_signals & SerialSignal_RI)
		strcat(stat_buf, "|RI");

	if (info->params.mode == MGSL_MODE_HDLC) {
		ret += sprintf(buf+ret, "\tHDLC txok:%d rxok:%d",
			      info->icount.txok, info->icount.rxok);
		if (info->icount.txunder)
			ret += sprintf(buf+ret, " txunder:%d", info->icount.txunder);
		if (info->icount.txabort)
			ret += sprintf(buf+ret, " txabort:%d", info->icount.txabort);
		if (info->icount.rxshort)
			ret += sprintf(buf+ret, " rxshort:%d", info->icount.rxshort);
		if (info->icount.rxlong)
			ret += sprintf(buf+ret, " rxlong:%d", info->icount.rxlong);
		if (info->icount.rxover)
			ret += sprintf(buf+ret, " rxover:%d", info->icount.rxover);
		if (info->icount.rxcrc)
			ret += sprintf(buf+ret, " rxlong:%d", info->icount.rxcrc);
	} else {