From 1fa0f4ea5660bf4731cf8f51c4ad923070b27fc8 Mon Sep 17 00:00:00 2001 From: Sergiu Cuciurean Date: Fri, 11 Apr 2025 12:57:09 -0300 Subject: [PATCH] iio: adc: ad7768-1: Add reset gpio Implement asynchronous hardware reset GPIO. Reviewed-by: David Lechner Reviewed-by: Marcelo Schmitt Signed-off-by: Sergiu Cuciurean Co-developed-by: Jonathan Santos Signed-off-by: Jonathan Santos Link: https://patch.msgid.link/25a413babeddf29583f1c26abf4234dfd606a595.1744325346.git.Jonathan.Santos@analog.com Signed-off-by: Jonathan Cameron --- drivers/iio/adc/ad7768-1.c | 36 ++++++++++++++++++++++++------------ 1 file changed, 24 insertions(+), 12 deletions(-) diff --git a/drivers/iio/adc/ad7768-1.c b/drivers/iio/adc/ad7768-1.c index 017d24d0bcd8..34712d3756e2 100644 --- a/drivers/iio/adc/ad7768-1.c +++ b/drivers/iio/adc/ad7768-1.c @@ -163,6 +163,7 @@ struct ad7768_state { struct completion completion; struct iio_trigger *trig; struct gpio_desc *gpio_sync_in; + struct gpio_desc *gpio_reset; const char *labels[ARRAY_SIZE(ad7768_channels)]; /* * DMA (thus cache coherency maintenance) may require the @@ -487,19 +488,30 @@ static int ad7768_setup(struct ad7768_state *st) { int ret; - /* - * Two writes to the SPI_RESET[1:0] bits are required to initiate - * a software reset. The bits must first be set to 11, and then - * to 10. When the sequence is detected, the reset occurs. - * See the datasheet, page 70. - */ - ret = regmap_write(st->regmap, AD7768_REG_SYNC_RESET, 0x3); - if (ret) - return ret; + st->gpio_reset = devm_gpiod_get_optional(&st->spi->dev, "reset", + GPIOD_OUT_HIGH); + if (IS_ERR(st->gpio_reset)) + return PTR_ERR(st->gpio_reset); - ret = regmap_write(st->regmap, AD7768_REG_SYNC_RESET, 0x2); - if (ret) - return ret; + if (st->gpio_reset) { + fsleep(10); + gpiod_set_value_cansleep(st->gpio_reset, 0); + fsleep(200); + } else { + /* + * Two writes to the SPI_RESET[1:0] bits are required to initiate + * a software reset. The bits must first be set to 11, and then + * to 10. When the sequence is detected, the reset occurs. + * See the datasheet, page 70. + */ + ret = regmap_write(st->regmap, AD7768_REG_SYNC_RESET, 0x3); + if (ret) + return ret; + + ret = regmap_write(st->regmap, AD7768_REG_SYNC_RESET, 0x2); + if (ret) + return ret; + } st->gpio_sync_in = devm_gpiod_get(&st->spi->dev, "adi,sync-in", GPIOD_OUT_LOW); -- 2.25.1