From: Adi Nata <adinata.softwareengineer@gmail.com>
To: lorenzo@kernel.org,
	jic23@kernel.org,
	dlechner@baylibre.com,
	nuno.sa@analog.com,
	andy@kernel.org,
	linux-iio@vger.kernel.org,
	linux-kernel@vger.kernel.org
Cc: linux-kernel-mentees@lists.linux.dev,
	Adi Nata <adinata.softwareengineer@gmail.com>
Subject: [PATCH v2 3/5] iio: humidity: hts221: Allow unknown whoami for DT fallback
Date: Thu, 13 Aug 2026 23:31:27 +0800
Message-ID: <20260813153129.12423-4-adinata.softwareengineer@gmail.com>
In-Reply-To: <20260813153129.12423-1-adinata.softwareengineer@gmail.com>
References: <20260813153129.12423-1-adinata.softwareengineer@gmail.com>
Precedence: bulk
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit

The WHOAMI check currently returns -ENODEV when the chip ID is not
0xbc. That rejects Device Tree fallback compatibles.

Keep failing if the WHOAMI register cannot be read. On an unexpected
ID, log it and continue so OF fallback matching can work.

Use dev_err_probe() for the read-failure path.

Signed-off-by: Adi Nata <adinata.softwareengineer@gmail.com>
---
 drivers/iio/humidity/hts221_core.c | 14 +++++---------
 1 file changed, 5 insertions(+), 9 deletions(-)

diff --git a/drivers/iio/humidity/hts221_core.c b/drivers/iio/humidity/hts221_core.c
index 76a391f421f5..b73c26aae9ec 100644
--- a/drivers/iio/humidity/hts221_core.c
+++ b/drivers/iio/humidity/hts221_core.c
@@ -136,19 +136,15 @@ static const struct iio_chan_spec hts221_channels[] = {
 
 static int hts221_check_whoami(struct hts221_hw *hw)
 {
+	struct device *dev = hw->dev;
 	int err, data;
 
 	err = regmap_read(hw->regmap, HTS221_REG_WHOAMI_ADDR, &data);
-	if (err < 0) {
-		dev_err(hw->dev, "failed to read whoami register\n");
-		return err;
-	}
+	if (err < 0)
+		return dev_err_probe(dev, err, "failed to read whoami register\n");
 
-	if (data != HTS221_REG_WHOAMI_VAL) {
-		dev_err(hw->dev, "wrong whoami {%02x vs %02x}\n",
-			data, HTS221_REG_WHOAMI_VAL);
-		return -ENODEV;
-	}
+	if (data != HTS221_REG_WHOAMI_VAL)
+		dev_info(dev, "unexpected whoami 0x%02x, continuing\n", data);
 
 	return 0;
 }
-- 
2.47.3