From bbf6b6d53e29b6db4f31eb25b5533a12b9134302 Mon Sep 17 00:00:00 2001 From: Christophe JAILLET Date: Fri, 6 Dec 2024 17:39:28 +0100 Subject: [PATCH] iio: adc: ad9467: Fix the "don't allow reading vref if not available" case The commit in Fixes adds a special case when only one possible scale is available. If several scales are available, it sets the .read_avail field of the struct iio_info to ad9467_read_avail(). However, this field already holds this function pointer, so the code is a no-op. Use another struct iio_info instead to actually reflect the intent described in the commit message. This way, the structure to use is selected at runtime and they can be kept as const. This is safer because modifying static structs that are shared between all instances like this, based on the properties of a single instance, is asking for trouble down the road. Fixes: b92f94f74826 ("iio: adc: ad9467: don't allow reading vref if not available") Signed-off-by: Christophe JAILLET Link: https://patch.msgid.link/cc65da19e0578823d29e11996f86042e84d5715c.1733503146.git.christophe.jaillet@wanadoo.fr Signed-off-by: Jonathan Cameron --- drivers/iio/adc/ad9467.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/drivers/iio/adc/ad9467.c b/drivers/iio/adc/ad9467.c index d358958ab3108..f30119b42ba0c 100644 --- a/drivers/iio/adc/ad9467.c +++ b/drivers/iio/adc/ad9467.c @@ -895,7 +895,7 @@ static int ad9467_update_scan_mode(struct iio_dev *indio_dev, return 0; } -static struct iio_info ad9467_info = { +static const struct iio_info ad9467_info = { .read_raw = ad9467_read_raw, .write_raw = ad9467_write_raw, .update_scan_mode = ad9467_update_scan_mode, @@ -903,6 +903,14 @@ static struct iio_info ad9467_info = { .read_avail = ad9467_read_avail, }; +/* Same as above, but without .read_avail */ +static const struct iio_info ad9467_info_no_read_avail = { + .read_raw = ad9467_read_raw, + .write_raw = ad9467_write_raw, + .update_scan_mode = ad9467_update_scan_mode, + .debugfs_reg_access = ad9467_reg_access, +}; + static int ad9467_scale_fill(struct ad9467_state *st) { const struct ad9467_chip_info *info = st->info; @@ -1214,11 +1222,12 @@ static int ad9467_probe(struct spi_device *spi) } if (st->info->num_scales > 1) - ad9467_info.read_avail = ad9467_read_avail; + indio_dev->info = &ad9467_info; + else + indio_dev->info = &ad9467_info_no_read_avail; indio_dev->name = st->info->name; indio_dev->channels = st->info->channels; indio_dev->num_channels = st->info->num_channels; - indio_dev->info = &ad9467_info; ret = ad9467_iio_backend_get(st); if (ret)