patch "iio: adc: ad4080: fix chip identification" added to char-misc-next

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    iio: adc: ad4080: fix chip identification

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-next 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 also be merged in the next major kernel release
during the merge window.

If you have any questions about this process, please let me know.


From b66cddc8be7278fd14650ff9182f3794397f8b31 Mon Sep 17 00:00:00 2001
From: Antoniu Miclaus <antoniu.miclaus@analog.com>
Date: Tue, 7 Oct 2025 11:15:20 +0000
Subject: iio: adc: ad4080: fix chip identification
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Fix AD4080 chip identification by using the correct 16-bit product ID
(0x0050) instead of GENMASK(2, 0). Update the chip reading logic to
use regmap_bulk_read to read both PRODUCT_ID_L and PRODUCT_ID_H
registers and combine them into a 16-bit value.

The original implementation was incorrectly reading only 3 bits,
which would not correctly identify the AD4080 chip.

Fixes: 6b31ba1811b6 ("iio: adc: ad4080: add driver support")
Signed-off-by: Antoniu Miclaus <antoniu.miclaus@analog.com>
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
---
 drivers/iio/adc/ad4080.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/iio/adc/ad4080.c b/drivers/iio/adc/ad4080.c
index 6e61787ed321..e15310fcd21a 100644
--- a/drivers/iio/adc/ad4080.c
+++ b/drivers/iio/adc/ad4080.c
@@ -125,7 +125,7 @@
 
 /* Miscellaneous Definitions */
 #define AD4080_SPI_READ						BIT(7)
-#define AD4080_CHIP_ID						GENMASK(2, 0)
+#define AD4080_CHIP_ID						0x0050
 
 #define AD4080_LVDS_CNV_CLK_CNT_MAX				7
 
@@ -445,7 +445,8 @@ static int ad4080_setup(struct iio_dev *indio_dev)
 {
 	struct ad4080_state *st = iio_priv(indio_dev);
 	struct device *dev = regmap_get_device(st->regmap);
-	unsigned int id;
+	__le16 id_le;
+	u16 id;
 	int ret;
 
 	ret = regmap_write(st->regmap, AD4080_REG_INTERFACE_CONFIG_A,
@@ -458,10 +459,12 @@ static int ad4080_setup(struct iio_dev *indio_dev)
 	if (ret)
 		return ret;
 
-	ret = regmap_read(st->regmap, AD4080_REG_CHIP_TYPE, &id);
+	ret = regmap_bulk_read(st->regmap, AD4080_REG_PRODUCT_ID_L, &id_le,
+			       sizeof(id_le));
 	if (ret)
 		return ret;
 
+	id = le16_to_cpu(id_le);
 	if (id != AD4080_CHIP_ID)
 		dev_info(dev, "Unrecognized CHIP_ID 0x%X\n", id);
 
-- 
2.52.0