[PATCH 03/38] media: qt1010: fix usage of unititialized value

From: Mauro Carvalho Chehab
Date: Wed Sep 02 2020 - 12:11:57 EST


As pointed by smatch:

drivers/media/tuners/qt1010.c:239 qt1010_init_meas1() error: uninitialized symbol 'val2'.
drivers/media/tuners/qt1010.c:273 qt1010_init_meas2() error: uninitialized symbol 'val'.

The logic is ok, but it is hard for static analyzers
to parse it, as it depends on a value read in the middle
of a loop.

Also, it takes a while for humans to verify.

Re-write the first function to use a more direct way.

At the second one, I opted to just initialize the read var,
in order to shut up the report.

While here, address a few coding style issues at the
function code.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx>
---
drivers/media/tuners/qt1010.c | 25 ++++++++++++++-----------
1 file changed, 14 insertions(+), 11 deletions(-)

diff --git a/drivers/media/tuners/qt1010.c b/drivers/media/tuners/qt1010.c
index e48faf942830..3853a3d43d4f 100644
--- a/drivers/media/tuners/qt1010.c
+++ b/drivers/media/tuners/qt1010.c
@@ -222,23 +222,24 @@ static int qt1010_init_meas1(struct qt1010_priv *priv,
{ QT1010_WR, reg, reg_init_val },
{ QT1010_WR, 0x1e, 0x00 },
{ QT1010_WR, 0x1e, oper },
- { QT1010_RD, reg, 0xff }
};

for (i = 0; i < ARRAY_SIZE(i2c_data); i++) {
- if (i2c_data[i].oper == QT1010_WR) {
- err = qt1010_writereg(priv, i2c_data[i].reg,
- i2c_data[i].val);
- } else {
- err = qt1010_readreg(priv, i2c_data[i].reg, &val2);
- }
- if (err) return err;
+ err = qt1010_writereg(priv, i2c_data[i].reg,
+ i2c_data[i].val);
+ if (err)
+ return err;
}

+ err = qt1010_readreg(priv, reg, &val2);
+ if (err)
+ return err;
do {
val1 = val2;
err = qt1010_readreg(priv, reg, &val2);
- if (err) return err;
+ if (err)
+ return err;
+
dev_dbg(&priv->i2c->dev, "%s: compare reg:%02x %02x %02x\n",
__func__, reg, val1, val2);
} while (val1 != val2);
@@ -250,7 +251,7 @@ static int qt1010_init_meas1(struct qt1010_priv *priv,
static int qt1010_init_meas2(struct qt1010_priv *priv,
u8 reg_init_val, u8 *retval)
{
- u8 i, val;
+ u8 i, val = 0xff;
int err;
qt1010_i2c_oper_t i2c_data[] = {
{ QT1010_WR, 0x07, reg_init_val },
@@ -261,6 +262,7 @@ static int qt1010_init_meas2(struct qt1010_priv *priv,
{ QT1010_WR, 0x1e, 0x00 },
{ QT1010_WR, 0x22, 0xff }
};
+
for (i = 0; i < ARRAY_SIZE(i2c_data); i++) {
if (i2c_data[i].oper == QT1010_WR) {
err = qt1010_writereg(priv, i2c_data[i].reg,
@@ -268,7 +270,8 @@ static int qt1010_init_meas2(struct qt1010_priv *priv,
} else {
err = qt1010_readreg(priv, i2c_data[i].reg, &val);
}
- if (err) return err;
+ if (err)
+ return err;
}
*retval = val;
return 0;
--
2.26.2