iio: adc: ad_pulsar: initial support for turbo gpio

This adds initial support for the TURBO gpio. The TURBO input is available on some chips (e.g. AD7944) and is used to enable the maximum sample rate at the expense of increased power consumption. For now, the TURBO mode is always enabled. In the future, we can add support to turn it off for lower sample rates. Signed-off-by: David Lechner <[email protected]>
nahtshur · Oct 31, 2023 · 19098a4 · 19098a4
1 parent 9168247
commit 19098a4
Showing 1 changed file with 9 additions and 0 deletions.
diff --git a/drivers/iio/adc/ad_pulsar.c b/drivers/iio/adc/ad_pulsar.c
@@ -14,6 +14,7 @@
 #include <linux/dma-mapping.h>
 #include <linux/dmaengine.h>
 #include <linux/err.h>
+#include <linux/gpio/consumer.h>
 #include <linux/jiffies.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
@@ -327,6 +328,7 @@ struct ad_pulsar_adc {
 	const struct ad_pulsar_chip_info *info;
 	struct iio_chan_spec *channels;
 	struct spi_transfer *seq_xfer;
+	struct gpio_desc *turbo_gpio;
 	unsigned int cfg;
 	unsigned long ref_clk_rate;
 	struct pwm_device *cnv;
@@ -911,6 +913,13 @@ static int ad_pulsar_probe(struct spi_device *spi)
 	if (ret)
 		return ret;
 
+	/* REVISIT: for now, turbo mode is always enabled */
+	adc->turbo_gpio = devm_gpiod_get_optional(&spi->dev, "turbo",
+						  GPIOD_OUT_HIGH);
+	if (IS_ERR(adc->turbo_gpio))
+		return dev_err_probe(&spi->dev, PTR_ERR(adc->turbo_gpio),
+				     "Failed to get turbo GPIO\n");
+
 	return devm_iio_device_register(&spi->dev, indio_dev);
 }