Commit f07ef395 authored by Jeff Garzik's avatar Jeff Garzik
Browse files

drivers/char/riscom8: clean up irq handling 



Make irq handling more efficient, by passing board pointer via
request_irq() to our irq handler's dev_id argument.

This eliminates a table lookup upon each interrupt, and eliminates an
associated global variable (the table).

Signed-off-by: default avatarJeff Garzik <jgarzik@redhat.com>
parent 080eb42f

drivers/char/riscom8.c

+5 −11
Original line number Diff line number Diff line
@@ -79,7 +79,6 @@ 


#define RS_EVENT_WRITE_WAKEUP	0



static struct riscom_board * IRQ_to_board[16];

static struct tty_driver *riscom_driver;



static struct riscom_board rc_board[RC_NBOARD] =  {
@@ -537,16 +536,14 @@ static inline void rc_check_modem(struct riscom_board const * bp) 
}



/* The main interrupt processing routine */

static irqreturn_t rc_interrupt(int irq, void * dev_id)

static irqreturn_t rc_interrupt(int dummy, void * dev_id)

{

	unsigned char status;

	unsigned char ack;

	struct riscom_board *bp;

	struct riscom_board *bp = dev_id;

	unsigned long loop = 0;

	int handled = 0;



	bp = IRQ_to_board[irq];



	if (!(bp->flags & RC_BOARD_ACTIVE))

		return IRQ_NONE;
@@ -603,7 +600,7 @@ static irqreturn_t rc_interrupt(int irq, void * dev_id) 
 */



/* Called with disabled interrupts */

static inline int rc_setup_board(struct riscom_board * bp)

static int rc_setup_board(struct riscom_board * bp)

{

	int error;
@@ -611,7 +608,7 @@ static inline int rc_setup_board(struct riscom_board * bp) 
		return 0;

	

	error = request_irq(bp->irq, rc_interrupt, IRQF_DISABLED,

			    "RISCom/8", NULL);

			    "RISCom/8", bp);

	if (error) 

		return error;
@@ -619,14 +616,13 @@ static inline int rc_setup_board(struct riscom_board * bp) 
	bp->DTR = ~0;

	rc_out(bp, RC_DTR, bp->DTR);	        /* Drop DTR on all ports */

	

	IRQ_to_board[bp->irq] = bp;

	bp->flags |= RC_BOARD_ACTIVE;

	

	return 0;

}



/* Called with disabled interrupts */

static inline void rc_shutdown_board(struct riscom_board *bp)

static void rc_shutdown_board(struct riscom_board *bp)

{

	if (!(bp->flags & RC_BOARD_ACTIVE))

		return;
@@ -634,7 +630,6 @@ static inline void rc_shutdown_board(struct riscom_board *bp) 
	bp->flags &= ~RC_BOARD_ACTIVE;

	

	free_irq(bp->irq, NULL);

	IRQ_to_board[bp->irq] = NULL;

	

	bp->DTR = ~0;

	rc_out(bp, RC_DTR, bp->DTR);	       /* Drop DTR on all ports */
@@ -1594,7 +1589,6 @@ static inline int rc_init_drivers(void) 
	if (!riscom_driver)	

		return -ENOMEM;

	

	memset(IRQ_to_board, 0, sizeof(IRQ_to_board));

	riscom_driver->owner = THIS_MODULE;

	riscom_driver->name = "ttyL";

	riscom_driver->major = RISCOM8_NORMAL_MAJOR;

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