misc: st_core: Protect unsigned value against becoming negative
Coverity reported:
This less-than-zero comparison of an unsigned value is never true.
In answer to that, we only ever decrement if protos_registered is
positive. We can subsequently remove the paranoid checking during
unregister.
Cc: gregkh@linuxfoundation.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
diff --git a/drivers/misc/ti-st/st_core.c b/drivers/misc/ti-st/st_core.c
index 1972d57..54be83d 100644
--- a/drivers/misc/ti-st/st_core.c
+++ b/drivers/misc/ti-st/st_core.c
@@ -153,8 +153,9 @@
(st_gdata->list[i]->priv_data, err);
pr_info("protocol %d's cb sent %d\n", i, err);
if (err) { /* cleanup registered protocol */
- st_gdata->protos_registered--;
st_gdata->is_registered[i] = false;
+ if (st_gdata->protos_registered)
+ st_gdata->protos_registered--;
}
}
}
@@ -639,14 +640,12 @@
return -EPROTONOSUPPORT;
}
- st_gdata->protos_registered--;
+ if (st_gdata->protos_registered)
+ st_gdata->protos_registered--;
+
remove_channel_from_table(st_gdata, proto);
spin_unlock_irqrestore(&st_gdata->lock, flags);
- /* paranoid check */
- if (st_gdata->protos_registered < ST_EMPTY)
- st_gdata->protos_registered = ST_EMPTY;
-
if ((st_gdata->protos_registered == ST_EMPTY) &&
(!test_bit(ST_REG_PENDING, &st_gdata->st_state))) {
pr_info(" all chnl_ids unregistered ");