lkml.org 
[lkml]   [2022]   [Apr]   [9]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] usb: typec: tipd: improve handling of failures in interrupt handlers
Date
clang static analysis reports this representative issue
core.c:516:6: warning: Branch condition evaluates
to a garbage value
if (event)
^~~~~

In cd321x_interrupt(), a successful call to
tps6598x_read64() is the only way event is set,
and if a failure happens the irq should not be
reported as handled.

Instead of initializing event, rework the
usage of ret by initializing it to IRQ_NONE
and then setting it when event is known to
be not zero. This removes the if-statement
before the return.

tps6598x_interrupt() is similar.

Fixes: 0a4c005bd171 ("usb: typec: driver for TI TPS6598x USB Power Delivery controllers")
Signed-off-by: Tom Rix <trix@redhat.com>
---
drivers/usb/typec/tipd/core.c | 24 +++++++++++-------------
1 file changed, 11 insertions(+), 13 deletions(-)

diff --git a/drivers/usb/typec/tipd/core.c b/drivers/usb/typec/tipd/core.c
index 16b4560216ba..88a20cc15da4 100644
--- a/drivers/usb/typec/tipd/core.c
+++ b/drivers/usb/typec/tipd/core.c
@@ -478,12 +478,11 @@ static irqreturn_t cd321x_interrupt(int irq, void *data)
struct tps6598x *tps = data;
u64 event;
u32 status;
- int ret;
+ int ret = IRQ_NONE;

mutex_lock(&tps->lock);

- ret = tps6598x_read64(tps, TPS_REG_INT_EVENT1, &event);
- if (ret) {
+ if (tps6598x_read64(tps, TPS_REG_INT_EVENT1, &event)) {
dev_err(tps->dev, "%s: failed to read events\n", __func__);
goto err_unlock;
}
@@ -492,6 +491,8 @@ static irqreturn_t cd321x_interrupt(int irq, void *data)
if (!event)
goto err_unlock;

+ ret = IRQ_HANDLED;
+
if (!tps6598x_read_status(tps, &status))
goto err_clear_ints;

@@ -513,9 +514,7 @@ static irqreturn_t cd321x_interrupt(int irq, void *data)
err_unlock:
mutex_unlock(&tps->lock);

- if (event)
- return IRQ_HANDLED;
- return IRQ_NONE;
+ return ret;
}

static irqreturn_t tps6598x_interrupt(int irq, void *data)
@@ -524,13 +523,12 @@ static irqreturn_t tps6598x_interrupt(int irq, void *data)
u64 event1;
u64 event2;
u32 status;
- int ret;
+ int ret = IRQ_NONE;

mutex_lock(&tps->lock);

- ret = tps6598x_read64(tps, TPS_REG_INT_EVENT1, &event1);
- ret |= tps6598x_read64(tps, TPS_REG_INT_EVENT2, &event2);
- if (ret) {
+ if (tps6598x_read64(tps, TPS_REG_INT_EVENT1, &event1) ||
+ tps6598x_read64(tps, TPS_REG_INT_EVENT2, &event2)) {
dev_err(tps->dev, "%s: failed to read events\n", __func__);
goto err_unlock;
}
@@ -539,6 +537,8 @@ static irqreturn_t tps6598x_interrupt(int irq, void *data)
if (!(event1 | event2))
goto err_unlock;

+ ret = IRQ_HANDLED;
+
if (!tps6598x_read_status(tps, &status))
goto err_clear_ints;

@@ -561,9 +561,7 @@ static irqreturn_t tps6598x_interrupt(int irq, void *data)
err_unlock:
mutex_unlock(&tps->lock);

- if (event1 | event2)
- return IRQ_HANDLED;
- return IRQ_NONE;
+ return ret;
}

static int tps6598x_check_mode(struct tps6598x *tps)
--
2.27.0
\
 
 \ /
  Last update: 2022-04-09 15:01    [W:0.032 / U:2.104 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site