patch "iio: adc: ad7380: fix supplies for ad7380-4" added to char-misc-linus

[<gregkh@linuxfoundation.org>]

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

    iio: adc: ad7380: fix supplies for ad7380-4

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 05f9c67179c9a8d66dee175fb4b17f380908a26f Mon Sep 17 00:00:00 2001
From: Julien Stephan <jstephan@baylibre.com>
Date: Tue, 22 Oct 2024 15:22:39 +0200
Subject: iio: adc: ad7380: fix supplies for ad7380-4

ad7380-4 is the only device in the family that does not have an internal
reference. It uses "refin" as a required external reference.
All other devices in the family use "refio"" as an optional external
reference.

Fixes: 737413da8704 ("iio: adc: ad7380: add support for ad738x-4 4 channels variants")
Reviewed-by: Nuno Sa <nuno.sa@analog.com>
Reviewed-by: David Lechner <dlechner@baylibre.com>
Signed-off-by: Julien Stephan <jstephan@baylibre.com>
Link: https://patch.msgid.link/20241022-ad7380-fix-supplies-v3-4-f0cefe1b7fa6@baylibre.com
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
---
 drivers/iio/adc/ad7380.c | 36 ++++++++++++++++++++++++++----------
 1 file changed, 26 insertions(+), 10 deletions(-)

diff --git a/drivers/iio/adc/ad7380.c b/drivers/iio/adc/ad7380.c
index b107d8e97ab3..fb728570debe 100644
--- a/drivers/iio/adc/ad7380.c
+++ b/drivers/iio/adc/ad7380.c
@@ -89,6 +89,7 @@ struct ad7380_chip_info {
 	bool has_mux;
 	const char * const *supplies;
 	unsigned int num_supplies;
+	bool external_ref_only;
 	const char * const *vcm_supplies;
 	unsigned int num_vcm_supplies;
 	const unsigned long *available_scan_masks;
@@ -431,6 +432,7 @@ static const struct ad7380_chip_info ad7380_4_chip_info = {
 	.num_simult_channels = 4,
 	.supplies = ad7380_supplies,
 	.num_supplies = ARRAY_SIZE(ad7380_supplies),
+	.external_ref_only = true,
 	.available_scan_masks = ad7380_4_channel_scan_masks,
 	.timing_specs = &ad7380_4_timing,
 };
@@ -1047,17 +1049,31 @@ static int ad7380_probe(struct spi_device *spi)
 				     "Failed to enable power supplies\n");
 	fsleep(T_POWERUP_US);
 
-	/*
-	 * If there is no REFIO supply, then it means that we are using
-	 * the internal 2.5V reference, otherwise REFIO is reference voltage.
-	 */
-	ret = devm_regulator_get_enable_read_voltage(&spi->dev, "refio");
-	if (ret < 0 && ret != -ENODEV)
-		return dev_err_probe(&spi->dev, ret,
-				     "Failed to get refio regulator\n");
+	if (st->chip_info->external_ref_only) {
+		ret = devm_regulator_get_enable_read_voltage(&spi->dev,
+							     "refin");
+		if (ret < 0)
+			return dev_err_probe(&spi->dev, ret,
+					     "Failed to get refin regulator\n");
 
-	external_ref_en = ret != -ENODEV;
-	st->vref_mv = external_ref_en ? ret / 1000 : AD7380_INTERNAL_REF_MV;
+		st->vref_mv = ret / 1000;
+
+		/* these chips don't have a register bit for this */
+		external_ref_en = false;
+	} else {
+		/*
+		 * If there is no REFIO supply, then it means that we are using
+		 * the internal reference, otherwise REFIO is reference voltage.
+		 */
+		ret = devm_regulator_get_enable_read_voltage(&spi->dev,
+							     "refio");
+		if (ret < 0 && ret != -ENODEV)
+			return dev_err_probe(&spi->dev, ret,
+					     "Failed to get refio regulator\n");
+
+		external_ref_en = ret != -ENODEV;
+		st->vref_mv = external_ref_en ? ret / 1000 : AD7380_INTERNAL_REF_MV;
+	}
 
 	if (st->chip_info->num_vcm_supplies > ARRAY_SIZE(st->vcm_mv))
 		return dev_err_probe(&spi->dev, -EINVAL,
-- 
2.47.0