synclink.c

来自「Linux Kernel 2.6.9 for OMAP1710」· C语言 代码 · 共 2,191 行 · 第 1/5 页

static int io[MAX_ISA_DEVICES];
static int irq[MAX_ISA_DEVICES];
static int dma[MAX_ISA_DEVICES];
static int debug_level;
static int maxframe[MAX_TOTAL_DEVICES];
static int dosyncppp[MAX_TOTAL_DEVICES];
static int txdmabufs[MAX_TOTAL_DEVICES];
static int txholdbufs[MAX_TOTAL_DEVICES];
	
MODULE_PARM(break_on_load,"i");
MODULE_PARM(ttymajor,"i");
MODULE_PARM(io,"1-" __MODULE_STRING(MAX_ISA_DEVICES) "i");
MODULE_PARM(irq,"1-" __MODULE_STRING(MAX_ISA_DEVICES) "i");
MODULE_PARM(dma,"1-" __MODULE_STRING(MAX_ISA_DEVICES) "i");
MODULE_PARM(debug_level,"i");
MODULE_PARM(maxframe,"1-" __MODULE_STRING(MAX_TOTAL_DEVICES) "i");
MODULE_PARM(dosyncppp,"1-" __MODULE_STRING(MAX_TOTAL_DEVICES) "i");
MODULE_PARM(txdmabufs,"1-" __MODULE_STRING(MAX_TOTAL_DEVICES) "i");
MODULE_PARM(txholdbufs,"1-" __MODULE_STRING(MAX_TOTAL_DEVICES) "i");

static char *driver_name = "SyncLink serial driver";
static char *driver_version = "$Revision: 4.28 $";

static int synclink_init_one (struct pci_dev *dev,
				     const struct pci_device_id *ent);
static void synclink_remove_one (struct pci_dev *dev);

static struct pci_device_id synclink_pci_tbl[] = {
	{ PCI_VENDOR_ID_MICROGATE, PCI_DEVICE_ID_MICROGATE_USC, PCI_ANY_ID, PCI_ANY_ID, },
	{ PCI_VENDOR_ID_MICROGATE, 0x0210, PCI_ANY_ID, PCI_ANY_ID, },
	{ 0, }, /* terminate list */
};
MODULE_DEVICE_TABLE(pci, synclink_pci_tbl);

MODULE_LICENSE("GPL");

static struct pci_driver synclink_pci_driver = {
	.name		= "synclink",
	.id_table	= synclink_pci_tbl,
	.probe		= synclink_init_one,
	.remove		= __devexit_p(synclink_remove_one),
};

static struct tty_driver *serial_driver;

/* number of characters left in xmit buffer before we ask for more */
#define WAKEUP_CHARS 256


static void mgsl_change_params(struct mgsl_struct *info);
static void mgsl_wait_until_sent(struct tty_struct *tty, int timeout);

/*
 * 1st function defined in .text section. Calling this function in
 * init_module() followed by a breakpoint allows a remote debugger
 * (gdb) to get the .text address for the add-symbol-file command.
 * This allows remote debugging of dynamically loadable modules.
 */
void* mgsl_get_text_ptr(void)
{
	return mgsl_get_text_ptr;
}

/*
 * tmp_buf is used as a temporary buffer by mgsl_write.  We need to
 * lock it in case the COPY_FROM_USER 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 ioports, since it significantly saves
 * memory if large numbers of serial ports are open.
 */
static unsigned char *tmp_buf;
static DECLARE_MUTEX(tmp_buf_sem);

static inline int mgsl_paranoia_check(struct mgsl_struct *info,
					char *name, const char *routine)
{
#ifdef MGSL_PARANOIA_CHECK
	static const char *badmagic =
		"Warning: bad magic number for mgsl struct (%s) in %s\n";
	static const char *badinfo =
		"Warning: null mgsl_struct for (%s) in %s\n";

	if (!info) {
		printk(badinfo, name, routine);
		return 1;
	}
	if (info->magic != MGSL_MAGIC) {
		printk(badmagic, name, routine);
		return 1;
	}
#else
	if (!info)
		return 1;
#endif
	return 0;
}

/**
 * line discipline callback wrappers
 *
 * The wrappers maintain line discipline references
 * while calling into the line discipline.
 *
 * ldisc_receive_buf  - pass receive data to line discipline
 */

static void ldisc_receive_buf(struct tty_struct *tty,
			      const __u8 *data, char *flags, int count)
{
	struct tty_ldisc *ld;
	if (!tty)
		return;
	ld = tty_ldisc_ref(tty);
	if (ld) {
		if (ld->receive_buf)
			ld->receive_buf(tty, data, flags, count);
		tty_ldisc_deref(ld);
	}
}

/* mgsl_stop()		throttle (stop) transmitter
 * 	
 * Arguments:		tty	pointer to tty info structure
 * Return Value:	None
 */
static void mgsl_stop(struct tty_struct *tty)
{
	struct mgsl_struct *info = (struct mgsl_struct *)tty->driver_data;
	unsigned long flags;
	
	if (mgsl_paranoia_check(info, tty->name, "mgsl_stop"))
		return;
	
	if ( debug_level >= DEBUG_LEVEL_INFO )
		printk("mgsl_stop(%s)\n",info->device_name);	
		
	spin_lock_irqsave(&info->irq_spinlock,flags);
	if (info->tx_enabled)
	 	usc_stop_transmitter(info);
	spin_unlock_irqrestore(&info->irq_spinlock,flags);
	
}	/* end of mgsl_stop() */

/* mgsl_start()		release (start) transmitter
 * 	
 * Arguments:		tty	pointer to tty info structure
 * Return Value:	None
 */
static void mgsl_start(struct tty_struct *tty)
{
	struct mgsl_struct *info = (struct mgsl_struct *)tty->driver_data;
	unsigned long flags;
	
	if (mgsl_paranoia_check(info, tty->name, "mgsl_start"))
		return;
	
	if ( debug_level >= DEBUG_LEVEL_INFO )
		printk("mgsl_start(%s)\n",info->device_name);	
		
	spin_lock_irqsave(&info->irq_spinlock,flags);
	if (!info->tx_enabled)
	 	usc_start_transmitter(info);
	spin_unlock_irqrestore(&info->irq_spinlock,flags);
	
}	/* end of mgsl_start() */

/*
 * Bottom half work queue access functions
 */

/* mgsl_bh_action()	Return next bottom half action to perform.
 * Return Value:	BH action code or 0 if nothing to do.
 */
int mgsl_bh_action(struct mgsl_struct *info)
{
	unsigned long flags;
	int rc = 0;
	
	spin_lock_irqsave(&info->irq_spinlock,flags);

	if (info->pending_bh & BH_RECEIVE) {
		info->pending_bh &= ~BH_RECEIVE;
		rc = BH_RECEIVE;
	} else if (info->pending_bh & BH_TRANSMIT) {
		info->pending_bh &= ~BH_TRANSMIT;
		rc = BH_TRANSMIT;
	} else if (info->pending_bh & BH_STATUS) {
		info->pending_bh &= ~BH_STATUS;
		rc = BH_STATUS;
	}

	if (!rc) {
		/* Mark BH routine as complete */
		info->bh_running   = 0;
		info->bh_requested = 0;
	}
	
	spin_unlock_irqrestore(&info->irq_spinlock,flags);
	
	return rc;
}

/*
 * 	Perform bottom half processing of work items queued by ISR.
 */
void mgsl_bh_handler(void* Context)
{
	struct mgsl_struct *info = (struct mgsl_struct*)Context;
	int action;

	if (!info)
		return;
		
	if ( debug_level >= DEBUG_LEVEL_BH )
		printk( "%s(%d):mgsl_bh_handler(%s) entry\n",
			__FILE__,__LINE__,info->device_name);
	
	info->bh_running = 1;

	while((action = mgsl_bh_action(info)) != 0) {
	
		/* Process work item */
		if ( debug_level >= DEBUG_LEVEL_BH )
			printk( "%s(%d):mgsl_bh_handler() work item action=%d\n",
				__FILE__,__LINE__,action);

		switch (action) {
		
		case BH_RECEIVE:
			mgsl_bh_receive(info);
			break;
		case BH_TRANSMIT:
			mgsl_bh_transmit(info);
			break;
		case BH_STATUS:
			mgsl_bh_status(info);
			break;
		default:
			/* unknown work item ID */
			printk("Unknown work item ID=%08X!\n", action);
			break;
		}
	}

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

void mgsl_bh_receive(struct mgsl_struct *info)
{
	int (*get_rx_frame)(struct mgsl_struct *info) =
		(info->params.mode == MGSL_MODE_HDLC ? mgsl_get_rx_frame : mgsl_get_raw_rx_frame);

	if ( debug_level >= DEBUG_LEVEL_BH )
		printk( "%s(%d):mgsl_bh_receive(%s)\n",
			__FILE__,__LINE__,info->device_name);
	
	do
	{
		if (info->rx_rcc_underrun) {
			unsigned long flags;
			spin_lock_irqsave(&info->irq_spinlock,flags);
			usc_start_receiver(info);
			spin_unlock_irqrestore(&info->irq_spinlock,flags);
			return;
		}
	} while(get_rx_frame(info));
}

void mgsl_bh_transmit(struct mgsl_struct *info)
{
	struct tty_struct *tty = info->tty;
	unsigned long flags;
	
	if ( debug_level >= DEBUG_LEVEL_BH )
		printk( "%s(%d):mgsl_bh_transmit() entry on %s\n",
			__FILE__,__LINE__,info->device_name);

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

	/* if transmitter idle and loopmode_send_done_requested
	 * then start echoing RxD to TxD
	 */
	spin_lock_irqsave(&info->irq_spinlock,flags);
 	if ( !info->tx_active && info->loopmode_send_done_requested )
 		usc_loopmode_send_done( info );
	spin_unlock_irqrestore(&info->irq_spinlock,flags);
}

void mgsl_bh_status(struct mgsl_struct *info)
{
	if ( debug_level >= DEBUG_LEVEL_BH )
		printk( "%s(%d):mgsl_bh_status() entry on %s\n",
			__FILE__,__LINE__,info->device_name);

	info->ri_chkcount = 0;
	info->dsr_chkcount = 0;
	info->dcd_chkcount = 0;
	info->cts_chkcount = 0;
}

/* mgsl_isr_receive_status()
 * 
 *	Service a receive status interrupt. The type of status
 *	interrupt is indicated by the state of the RCSR.
 *	This is only used for HDLC mode.
 *
 * Arguments:		info	pointer to device instance data
 * Return Value:	None
 */
void mgsl_isr_receive_status( struct mgsl_struct *info )
{
	u16 status = usc_InReg( info, RCSR );

	if ( debug_level >= DEBUG_LEVEL_ISR )	
		printk("%s(%d):mgsl_isr_receive_status status=%04X\n",
			__FILE__,__LINE__,status);
			
 	if ( (status & RXSTATUS_ABORT_RECEIVED) && 
		info->loopmode_insert_requested &&
 		usc_loopmode_active(info) )
 	{
		++info->icount.rxabort;
	 	info->loopmode_insert_requested = FALSE;
 
 		/* clear CMR:13 to start echoing RxD to TxD */
		info->cmr_value &= ~BIT13;
 		usc_OutReg(info, CMR, info->cmr_value);
 
		/* disable received abort irq (no longer required) */
	 	usc_OutReg(info, RICR,
 			(usc_InReg(info, RICR) & ~RXSTATUS_ABORT_RECEIVED));
 	}

	if (status & (RXSTATUS_EXITED_HUNT + RXSTATUS_IDLE_RECEIVED)) {
		if (status & RXSTATUS_EXITED_HUNT)
			info->icount.exithunt++;
		if (status & RXSTATUS_IDLE_RECEIVED)
			info->icount.rxidle++;
		wake_up_interruptible(&info->event_wait_q);
	}

	if (status & RXSTATUS_OVERRUN){
		info->icount.rxover++;
		usc_process_rxoverrun_sync( info );
	}

	usc_ClearIrqPendingBits( info, RECEIVE_STATUS );
	usc_UnlatchRxstatusBits( info, status );

}	/* end of mgsl_isr_receive_status() */

/* mgsl_isr_transmit_status()
 * 
 * 	Service a transmit status interrupt
 *	HDLC mode :end of transmit frame
 *	Async mode:all data is sent
 * 	transmit status is indicated by bits in the TCSR.
 * 
 * Arguments:		info	       pointer to device instance data
 * Return Value:	None
 */
void mgsl_isr_transmit_status( struct mgsl_struct *info )
{
	u16 status = usc_InReg( info, TCSR );

	if ( debug_level >= DEBUG_LEVEL_ISR )	
		printk("%s(%d):mgsl_isr_transmit_status status=%04X\n",
			__FILE__,__LINE__,status);
	
	usc_ClearIrqPendingBits( info, TRANSMIT_STATUS );
	usc_UnlatchTxstatusBits( info, status );
	
	if ( status & (TXSTATUS_UNDERRUN | TXSTATUS_ABORT_SENT) )
	{
		/* finished sending HDLC abort. This may leave	*/
		/* the TxFifo with data from the aborted frame	*/
		/* so purge the TxFifo. Also shutdown the DMA	*/
		/* channel in case there is data remaining in 	*/
		/* the DMA buffer				*/
 		usc_DmaCmd( info, DmaCmd_ResetTxChannel );
 		usc_RTCmd( info, RTCmd_PurgeTxFifo );
	}
 
	if ( status & TXSTATUS_EOF_SENT )
		info->icount.txok++;
	else if ( status & TXSTATUS_UNDERRUN )
		info->icount.txunder++;
	else if ( status & TXSTATUS_ABORT_SENT )
		info->icount.txabort++;
	else
		info->icount.txunder++;
			
	info->tx_active = 0;
	info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
	del_timer(&info->tx_timer);	
	
	if ( info->drop_rts_on_tx_done ) {
		usc_get_serial_signals( info );
		if ( info->serial_signals & SerialSignal_RTS ) {
			info->serial_signals &= ~SerialSignal_RTS;
			usc_set_serial_signals( info );
		}
		info->drop_rts_on_tx_done = 0;
	}

#ifdef CONFIG_HDLC
	if (info->netcount)
		hdlcdev_tx_done(info);
	else 
#endif
	{
		if (info->tty->stopped || info->tty->hw_stopped) {
			usc_stop_transmitter(info);
			return;
		}
		info->pending_bh |= BH_TRANSMIT;
	}

}	/* end of mgsl_isr_transmit_status() */

/* mgsl_isr_io_pin()
 * 
 * 	Service an Input/Output pin interrupt. The type of
 * 	interrupt is indicated by bits in the MISR
 * 	
 * Arguments:		info	       pointer to device instance data
 * Return Value:	None
 */
void mgsl_isr_io_pin( struct mgsl_struct *info )
{
 	struct	mgsl_icount *icount;
	u16 status = usc_InReg( info, MISR );