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: Jeff Garzik <jgarzik@redhat.com>
diff --git a/drivers/char/riscom8.c b/drivers/char/riscom8.c
index b37e626..102ece4 100644
--- a/drivers/char/riscom8.c
+++ b/drivers/char/riscom8.c
@@ -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 @@
}
/* 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 @@
*/
/* 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 @@
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 @@
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 @@
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 @@
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;