The ad7124-4 has 8 analog inputs; the input select values 8 to 15 are
reserved and not to be used. These are fine for ad7124-8. For both
ad7124-4 and ad7124-8 values bigger than 15 are internal channels that
might appear as inputs in the channels specified in the device
description according to the description of commit f1794fd7bdf7 ("iio:
adc: ad7124: Remove input number limitation"), values bigger than 31
don't fit into the respective register bit field and the driver masked
them to smaller values.
Check for these invalid input specifiers and fail to probe if one is
found.
Fixes: f1794fd7bdf7 ("iio: adc: ad7124: Remove input number limitation")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibe.com>
---
drivers/iio/adc/ad7124.c | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)
diff --git a/drivers/iio/adc/ad7124.c b/drivers/iio/adc/ad7124.c
index 7473bcef7bc6..bd5c0dbc0239 100644
--- a/drivers/iio/adc/ad7124.c
+++ b/drivers/iio/adc/ad7124.c
@@ -808,6 +808,19 @@ static int ad7124_check_chip_id(struct ad7124_state *st)
return 0;
}
+/*
+ * Input specifiers 8 - 15 are explicitly reserved for ad7124-4
+ * while they are fine for ad7124-8. Values above 31 don't fit
+ * into the register field and so are invalid for sure.
+ */
+static bool ad7124_valid_input_select(unsigned int ain, const struct ad7124_chip_info *info)
+{
+ if (ain >= info->num_inputs && ain < 16)
+ return false;
+
+ return ain <= FIELD_MAX(AD7124_CHANNEL_AINM_MSK);
+}
+
static int ad7124_parse_channel_config(struct iio_dev *indio_dev,
struct device *dev)
{
@@ -855,6 +868,11 @@ static int ad7124_parse_channel_config(struct iio_dev *indio_dev,
if (ret)
return ret;
+ if (!ad7124_valid_input_select(ain[0], st->chip_info) ||
+ !ad7124_valid_input_select(ain[1], st->chip_info))
+ return dev_err_probe(dev, ret,
+ "diff-channels property of %pfwP contains invalid data\n", child);
+
st->channels[channel].nr = channel;
st->channels[channel].ain = AD7124_CHANNEL_AINP(ain[0]) |
AD7124_CHANNEL_AINM(ain[1]);
--
2.45.2
Hi Uwe,
kernel test robot noticed the following build warnings:
url: https://github.com/intel-lab-lkp/linux/commits/Uwe-Kleine-K-nig/iio-adc-ad7124-Don-t-create-more-channels-than-the-hardware-is-capable-of/20241109-022036
base: 9852d85ec9d492ebef56dc5f229416c925758edc
patch link: https://lore.kernel.org/r/20241108181813.272593-6-u.kleine-koenig%40baylibre.com
patch subject: [PATCH 2/2] iio: adc: ad7124: Refuse invalid input specifiers
config: i386-randconfig-141-20241109 (https://download.01.org/0day-ci/archive/20241109/202411090908.Ynrg4eS0-lkp@intel.com/config)
compiler: gcc-12 (Debian 12.2.0-14) 12.2.0
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@intel.com>
| Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
| Closes: https://lore.kernel.org/r/202411090908.Ynrg4eS0-lkp@intel.com/
smatch warnings:
drivers/iio/adc/ad7124.c:874 ad7124_parse_channel_config() warn: passing zero to 'dev_err_probe'
vim +/dev_err_probe +874 drivers/iio/adc/ad7124.c
a6eaf02b82744b Jonathan Cameron 2024-02-18 824 static int ad7124_parse_channel_config(struct iio_dev *indio_dev,
a6eaf02b82744b Jonathan Cameron 2024-02-18 825 struct device *dev)
b3af341bbd9662 Stefan Popa 2018-11-13 826 {
b3af341bbd9662 Stefan Popa 2018-11-13 827 struct ad7124_state *st = iio_priv(indio_dev);
7b8d045e497a04 Alexandru Tachici 2021-03-11 828 struct ad7124_channel_config *cfg;
7b8d045e497a04 Alexandru Tachici 2021-03-11 829 struct ad7124_channel *channels;
b3af341bbd9662 Stefan Popa 2018-11-13 830 struct iio_chan_spec *chan;
b3af341bbd9662 Stefan Popa 2018-11-13 831 unsigned int ain[2], channel = 0, tmp;
b3af341bbd9662 Stefan Popa 2018-11-13 832 int ret;
b3af341bbd9662 Stefan Popa 2018-11-13 833
a6eaf02b82744b Jonathan Cameron 2024-02-18 834 st->num_channels = device_get_child_node_count(dev);
a6eaf02b82744b Jonathan Cameron 2024-02-18 835 if (!st->num_channels)
a6eaf02b82744b Jonathan Cameron 2024-02-18 836 return dev_err_probe(dev, -ENODEV, "no channel children\n");
b3af341bbd9662 Stefan Popa 2018-11-13 837
b478bd5e22404e Uwe Kleine-König 2024-11-08 838 if (st->num_channels > AD7124_MAX_CHANNELS) {
b478bd5e22404e Uwe Kleine-König 2024-11-08 839 dev_warn(dev, "Limit number of channels to " __stringify(AD7124_MAX_CHANNELS) "\n");
b478bd5e22404e Uwe Kleine-König 2024-11-08 840 st->num_channels = AD7124_MAX_CHANNELS;
b478bd5e22404e Uwe Kleine-König 2024-11-08 841 }
b478bd5e22404e Uwe Kleine-König 2024-11-08 842
b3af341bbd9662 Stefan Popa 2018-11-13 843 chan = devm_kcalloc(indio_dev->dev.parent, st->num_channels,
b3af341bbd9662 Stefan Popa 2018-11-13 844 sizeof(*chan), GFP_KERNEL);
b3af341bbd9662 Stefan Popa 2018-11-13 845 if (!chan)
b3af341bbd9662 Stefan Popa 2018-11-13 846 return -ENOMEM;
b3af341bbd9662 Stefan Popa 2018-11-13 847
7b8d045e497a04 Alexandru Tachici 2021-03-11 848 channels = devm_kcalloc(indio_dev->dev.parent, st->num_channels, sizeof(*channels),
7b8d045e497a04 Alexandru Tachici 2021-03-11 849 GFP_KERNEL);
7b8d045e497a04 Alexandru Tachici 2021-03-11 850 if (!channels)
1478a388f4baaa Mircea Caprioru 2019-06-25 851 return -ENOMEM;
1478a388f4baaa Mircea Caprioru 2019-06-25 852
b3af341bbd9662 Stefan Popa 2018-11-13 853 indio_dev->channels = chan;
b3af341bbd9662 Stefan Popa 2018-11-13 854 indio_dev->num_channels = st->num_channels;
7b8d045e497a04 Alexandru Tachici 2021-03-11 855 st->channels = channels;
b3af341bbd9662 Stefan Popa 2018-11-13 856
a6eaf02b82744b Jonathan Cameron 2024-02-18 857 device_for_each_child_node_scoped(dev, child) {
a6eaf02b82744b Jonathan Cameron 2024-02-18 858 ret = fwnode_property_read_u32(child, "reg", &channel);
b3af341bbd9662 Stefan Popa 2018-11-13 859 if (ret)
a6eaf02b82744b Jonathan Cameron 2024-02-18 860 return ret;
b3af341bbd9662 Stefan Popa 2018-11-13 861
a6eaf02b82744b Jonathan Cameron 2024-02-18 862 if (channel >= indio_dev->num_channels)
a6eaf02b82744b Jonathan Cameron 2024-02-18 863 return dev_err_probe(dev, -EINVAL,
f2a772c51206b0 Jonathan Cameron 2021-05-13 864 "Channel index >= number of channels\n");
f2a772c51206b0 Jonathan Cameron 2021-05-13 865
a6eaf02b82744b Jonathan Cameron 2024-02-18 866 ret = fwnode_property_read_u32_array(child, "diff-channels",
b3af341bbd9662 Stefan Popa 2018-11-13 867 ain, 2);
b3af341bbd9662 Stefan Popa 2018-11-13 868 if (ret)
a6eaf02b82744b Jonathan Cameron 2024-02-18 869 return ret;
b3af341bbd9662 Stefan Popa 2018-11-13 870
4112b30ba58b5c Uwe Kleine-König 2024-11-08 871 if (!ad7124_valid_input_select(ain[0], st->chip_info) ||
4112b30ba58b5c Uwe Kleine-König 2024-11-08 872 !ad7124_valid_input_select(ain[1], st->chip_info))
4112b30ba58b5c Uwe Kleine-König 2024-11-08 873 return dev_err_probe(dev, ret,
s/ret/-EINVAL/?
4112b30ba58b5c Uwe Kleine-König 2024-11-08 @874 "diff-channels property of %pfwP contains invalid data\n", child);
4112b30ba58b5c Uwe Kleine-König 2024-11-08 875
7b8d045e497a04 Alexandru Tachici 2021-03-11 876 st->channels[channel].nr = channel;
7b8d045e497a04 Alexandru Tachici 2021-03-11 877 st->channels[channel].ain = AD7124_CHANNEL_AINP(ain[0]) |
b3af341bbd9662 Stefan Popa 2018-11-13 878 AD7124_CHANNEL_AINM(ain[1]);
7b8d045e497a04 Alexandru Tachici 2021-03-11 879
61cbfb5368dd50 Dumitru Ceclan 2024-08-06 880 cfg = &st->channels[channel].cfg;
a6eaf02b82744b Jonathan Cameron 2024-02-18 881 cfg->bipolar = fwnode_property_read_bool(child, "bipolar");
b3af341bbd9662 Stefan Popa 2018-11-13 882
a6eaf02b82744b Jonathan Cameron 2024-02-18 883 ret = fwnode_property_read_u32(child, "adi,reference-select", &tmp);
b3af341bbd9662 Stefan Popa 2018-11-13 884 if (ret)
7b8d045e497a04 Alexandru Tachici 2021-03-11 885 cfg->refsel = AD7124_INT_REF;
b3af341bbd9662 Stefan Popa 2018-11-13 886 else
7b8d045e497a04 Alexandru Tachici 2021-03-11 887 cfg->refsel = tmp;
b3af341bbd9662 Stefan Popa 2018-11-13 888
a6eaf02b82744b Jonathan Cameron 2024-02-18 889 cfg->buf_positive =
a6eaf02b82744b Jonathan Cameron 2024-02-18 890 fwnode_property_read_bool(child, "adi,buffered-positive");
a6eaf02b82744b Jonathan Cameron 2024-02-18 891 cfg->buf_negative =
a6eaf02b82744b Jonathan Cameron 2024-02-18 892 fwnode_property_read_bool(child, "adi,buffered-negative");
0eaecea6e4878a Mircea Caprioru 2019-06-25 893
d7857e4ee1ba69 Alexandru Tachici 2019-12-20 894 chan[channel] = ad7124_channel_template;
d7857e4ee1ba69 Alexandru Tachici 2019-12-20 895 chan[channel].address = channel;
d7857e4ee1ba69 Alexandru Tachici 2019-12-20 896 chan[channel].scan_index = channel;
d7857e4ee1ba69 Alexandru Tachici 2019-12-20 897 chan[channel].channel = ain[0];
d7857e4ee1ba69 Alexandru Tachici 2019-12-20 898 chan[channel].channel2 = ain[1];
b3af341bbd9662 Stefan Popa 2018-11-13 899 }
b3af341bbd9662 Stefan Popa 2018-11-13 900
b3af341bbd9662 Stefan Popa 2018-11-13 901 return 0;
b3af341bbd9662 Stefan Popa 2018-11-13 902 }
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
[Dropped Mircea Caprioru from Cc: as the analog.com MTA doesn't know their address] Hello Dan, On Mon, Nov 11, 2024 at 12:15:45PM +0300, Dan Carpenter wrote: > 4112b30ba58b5c Uwe Kleine-König 2024-11-08 871 if (!ad7124_valid_input_select(ain[0], st->chip_info) || > 4112b30ba58b5c Uwe Kleine-König 2024-11-08 872 !ad7124_valid_input_select(ain[1], st->chip_info)) > 4112b30ba58b5c Uwe Kleine-König 2024-11-08 873 return dev_err_probe(dev, ret, > > s/ret/-EINVAL/? > > 4112b30ba58b5c Uwe Kleine-König 2024-11-08 @874 "diff-channels property of %pfwP contains invalid data\n", child); Indeed. I adapted that in my tree, so will be fixed in v2. Thanks Uwe
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