mISDN: fix a loop count

There are two issue here.
1)  cnt starts as maxloop + 1 so all these loops iterate one more time
    than intended.
2)  At the end of the loop we test for "if (maxloop && !cnt)" but for
    the first two loops, we end with cnt equal to -1.  Changing this to
    a pre-op means we end with cnt set to 0.

Fixes: cae86d4a4e ('mISDN: Add driver for Infineon ISDN chipset family')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Dan Carpenter 2015-12-15 13:07:52 +03:00 committed by David S. Miller
parent 2b2b31c845
commit 40d24c4d8a
1 changed files with 3 additions and 4 deletions

View File

@ -1170,7 +1170,7 @@ mISDNipac_irq(struct ipac_hw *ipac, int maxloop)
if (ipac->type & IPAC_TYPE_IPACX) {
ista = ReadIPAC(ipac, ISACX_ISTA);
while (ista && cnt--) {
while (ista && --cnt) {
pr_debug("%s: ISTA %02x\n", ipac->name, ista);
if (ista & IPACX__ICA)
ipac_irq(&ipac->hscx[0], ista);
@ -1182,7 +1182,7 @@ mISDNipac_irq(struct ipac_hw *ipac, int maxloop)
}
} else if (ipac->type & IPAC_TYPE_IPAC) {
ista = ReadIPAC(ipac, IPAC_ISTA);
while (ista && cnt--) {
while (ista && --cnt) {
pr_debug("%s: ISTA %02x\n", ipac->name, ista);
if (ista & (IPAC__ICD | IPAC__EXD)) {
istad = ReadISAC(isac, ISAC_ISTA);
@ -1200,7 +1200,7 @@ mISDNipac_irq(struct ipac_hw *ipac, int maxloop)
ista = ReadIPAC(ipac, IPAC_ISTA);
}
} else if (ipac->type & IPAC_TYPE_HSCX) {
while (cnt) {
while (--cnt) {
ista = ReadIPAC(ipac, IPAC_ISTAB + ipac->hscx[1].off);
pr_debug("%s: B2 ISTA %02x\n", ipac->name, ista);
if (ista)
@ -1211,7 +1211,6 @@ mISDNipac_irq(struct ipac_hw *ipac, int maxloop)
mISDNisac_irq(isac, istad);
if (0 == (ista | istad))
break;
cnt--;
}
}
if (cnt > maxloop) /* only for ISAC/HSCX without PCI IRQ test */