This is a note to let you know that I've just added the patch titled
iio: adc: ad7124: fix chip ID mismatch
to my char-misc git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git in the char-misc-linus branch.
The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.)
The patch will hopefully also be merged in Linus's tree for the next -rc kernel release.
If you have any questions about this process, please let me know.
From 96f9ab0d5933c1c00142dd052f259fce0bc3ced2 Mon Sep 17 00:00:00 2001 From: Dumitru Ceclan mitrutzceclan@gmail.com Date: Wed, 31 Jul 2024 15:37:22 +0300 Subject: iio: adc: ad7124: fix chip ID mismatch
The ad7124_soft_reset() function has the assumption that the chip will assert the "power-on reset" bit in the STATUS register after a software reset without any delay. The POR bit =0 is used to check if the chip initialization is done.
A chip ID mismatch probe error appears intermittently when the probe continues too soon and the ID register does not contain the expected value.
Fix by adding a 200us delay after the software reset command is issued.
Fixes: b3af341bbd96 ("iio: adc: Add ad7124 support") Signed-off-by: Dumitru Ceclan dumitru.ceclan@analog.com Reviewed-by: Nuno Sa nuno.sa@analog.com Link: https://patch.msgid.link/20240731-ad7124-fix-v1-1-46a76aa4b9be@analog.com Cc: Stable@vger.kernel.org Signed-off-by: Jonathan Cameron Jonathan.Cameron@huawei.com --- drivers/iio/adc/ad7124.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/drivers/iio/adc/ad7124.c b/drivers/iio/adc/ad7124.c index 3beed78496c5..c0b82f64c976 100644 --- a/drivers/iio/adc/ad7124.c +++ b/drivers/iio/adc/ad7124.c @@ -764,6 +764,7 @@ static int ad7124_soft_reset(struct ad7124_state *st) if (ret < 0) return ret;
+ fsleep(200); timeout = 100; do { ret = ad_sd_read_reg(&st->sd, AD7124_STATUS, 1, &readval);