Re: [PATCH] iio: chemical: scd4x: Add pressure compensation

From: Dan Carpenter
Date: Wed Jul 05 2023 - 09:04:09 EST

Hi Roan,

kernel test robot noticed the following build warnings:

https://git-scm.com/docs/git-format-patch#_base_tree_information]

url: https://github.com/intel-lab-lkp/linux/commits/Roan-van-Dijk/iio-chemical-scd4x-Add-pressure-compensation/20230704-170621
base: https://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio.git togreg
patch link: https://lore.kernel.org/r/20230704084706.370637-1-roan%40protonic.nl
patch subject: [PATCH] iio: chemical: scd4x: Add pressure compensation
config: x86_64-randconfig-m001-20230705 (https://download.01.org/0day-ci/archive/20230705/202307052018.7DV5CAOH-lkp@xxxxxxxxx/config)
compiler: gcc-12 (Debian 12.2.0-14) 12.2.0
reproduce: (https://download.01.org/0day-ci/archive/20230705/202307052018.7DV5CAOH-lkp@xxxxxxxxx/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@xxxxxxxxx>
| Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
| Closes: https://lore.kernel.org/r/202307052018.7DV5CAOH-lkp@xxxxxxxxx/

smatch warnings:
drivers/iio/chemical/scd4x.c:385 scd4x_read_raw() error: uninitialized symbol 'ret'.
drivers/iio/chemical/scd4x.c:388 scd4x_read_raw() error: uninitialized symbol 'tmp'.

vim +/ret +385 drivers/iio/chemical/scd4x.c

49d22b695cbb69 Roan van Dijk 2021-10-08 335 static int scd4x_read_raw(struct iio_dev *indio_dev,
49d22b695cbb69 Roan van Dijk 2021-10-08 336 struct iio_chan_spec const *chan, int *val,
49d22b695cbb69 Roan van Dijk 2021-10-08 337 int *val2, long mask)
49d22b695cbb69 Roan van Dijk 2021-10-08 338 {
49d22b695cbb69 Roan van Dijk 2021-10-08 339 struct scd4x_state *state = iio_priv(indio_dev);
49d22b695cbb69 Roan van Dijk 2021-10-08 340 int ret;
49d22b695cbb69 Roan van Dijk 2021-10-08 341 __be16 tmp;
49d22b695cbb69 Roan van Dijk 2021-10-08 342
49d22b695cbb69 Roan van Dijk 2021-10-08 343 switch (mask) {
49d22b695cbb69 Roan van Dijk 2021-10-08 344 case IIO_CHAN_INFO_RAW:
49d22b695cbb69 Roan van Dijk 2021-10-08 345 ret = iio_device_claim_direct_mode(indio_dev);
49d22b695cbb69 Roan van Dijk 2021-10-08 346 if (ret)
49d22b695cbb69 Roan van Dijk 2021-10-08 347 return ret;
49d22b695cbb69 Roan van Dijk 2021-10-08 348
49d22b695cbb69 Roan van Dijk 2021-10-08 349 mutex_lock(&state->lock);
49d22b695cbb69 Roan van Dijk 2021-10-08 350 ret = scd4x_read_channel(state, chan->address);
49d22b695cbb69 Roan van Dijk 2021-10-08 351 mutex_unlock(&state->lock);
49d22b695cbb69 Roan van Dijk 2021-10-08 352
49d22b695cbb69 Roan van Dijk 2021-10-08 353 iio_device_release_direct_mode(indio_dev);
49d22b695cbb69 Roan van Dijk 2021-10-08 354 if (ret < 0)
49d22b695cbb69 Roan van Dijk 2021-10-08 355 return ret;
49d22b695cbb69 Roan van Dijk 2021-10-08 356
49d22b695cbb69 Roan van Dijk 2021-10-08 357 *val = ret;
49d22b695cbb69 Roan van Dijk 2021-10-08 358 return IIO_VAL_INT;
49d22b695cbb69 Roan van Dijk 2021-10-08 359 case IIO_CHAN_INFO_SCALE:
e46e2512ac84bd Roan van Dijk 2021-10-21 360 if (chan->type == IIO_CONCENTRATION) {
e46e2512ac84bd Roan van Dijk 2021-10-21 361 *val = 0;
e46e2512ac84bd Roan van Dijk 2021-10-21 362 *val2 = 100;
e46e2512ac84bd Roan van Dijk 2021-10-21 363 return IIO_VAL_INT_PLUS_MICRO;
e46e2512ac84bd Roan van Dijk 2021-10-21 364 } else if (chan->type == IIO_TEMP) {
49d22b695cbb69 Roan van Dijk 2021-10-08 365 *val = 175000;
49d22b695cbb69 Roan van Dijk 2021-10-08 366 *val2 = 65536;
49d22b695cbb69 Roan van Dijk 2021-10-08 367 return IIO_VAL_FRACTIONAL;
49d22b695cbb69 Roan van Dijk 2021-10-08 368 } else if (chan->type == IIO_HUMIDITYRELATIVE) {
49d22b695cbb69 Roan van Dijk 2021-10-08 369 *val = 100000;
49d22b695cbb69 Roan van Dijk 2021-10-08 370 *val2 = 65536;
49d22b695cbb69 Roan van Dijk 2021-10-08 371 return IIO_VAL_FRACTIONAL;
49d22b695cbb69 Roan van Dijk 2021-10-08 372 }
49d22b695cbb69 Roan van Dijk 2021-10-08 373 return -EINVAL;
49d22b695cbb69 Roan van Dijk 2021-10-08 374 case IIO_CHAN_INFO_OFFSET:
49d22b695cbb69 Roan van Dijk 2021-10-08 375 *val = -16852;
49d22b695cbb69 Roan van Dijk 2021-10-08 376 *val2 = 114286;
49d22b695cbb69 Roan van Dijk 2021-10-08 377 return IIO_VAL_INT_PLUS_MICRO;
49d22b695cbb69 Roan van Dijk 2021-10-08 378 case IIO_CHAN_INFO_CALIBBIAS:
49d22b695cbb69 Roan van Dijk 2021-10-08 379 mutex_lock(&state->lock);
8e4a309948cffe Roan van Dijk 2023-07-04 380 if (chan->type == IIO_TEMP)
49d22b695cbb69 Roan van Dijk 2021-10-08 381 ret = scd4x_read(state, CMD_GET_TEMP_OFFSET, &tmp, sizeof(tmp));
8e4a309948cffe Roan van Dijk 2023-07-04 382 else if (chan->type == IIO_PRESSURE)
8e4a309948cffe Roan van Dijk 2023-07-04 383 ret = scd4x_read(state, CMD_GET_AMB_PRESSURE, &tmp, sizeof(tmp));

ret is uninitialized if type != IIO_TEMP and != IIO_PRESSURE.

49d22b695cbb69 Roan van Dijk 2021-10-08 384 mutex_unlock(&state->lock);
49d22b695cbb69 Roan van Dijk 2021-10-08 @385 if (ret)
49d22b695cbb69 Roan van Dijk 2021-10-08 386 return ret;
49d22b695cbb69 Roan van Dijk 2021-10-08 387
49d22b695cbb69 Roan van Dijk 2021-10-08 @388 *val = be16_to_cpu(tmp);
49d22b695cbb69 Roan van Dijk 2021-10-08 389
49d22b695cbb69 Roan van Dijk 2021-10-08 390 return IIO_VAL_INT;
49d22b695cbb69 Roan van Dijk 2021-10-08 391 default:
49d22b695cbb69 Roan van Dijk 2021-10-08 392 return -EINVAL;
49d22b695cbb69 Roan van Dijk 2021-10-08 393 }
49d22b695cbb69 Roan van Dijk 2021-10-08 394 }

--
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