[PATCH 1/3] iio: adc: ade9000: request interrupts after powering the device

[Antoniu Miclaus]

The IRQ handlers do SPI register accesses, but the interrupts were
requested before the vdd regulator was enabled. An interrupt arriving
while the chip is unpowered runs a handler against a dead chip, causing
SPI errors or garbage reads.

Request the interrupts after enabling the regulator. This keeps irq1
registered before ade9000_reset(), which waits on it, and lets devm free
the interrupts before the regulator is disabled.

Fixes: 81de7b4619fc ("iio: adc: add ade9000 support")
Signed-off-by: Antoniu Miclaus <antoniu.miclaus@xxxxxxxxxx>
---
 drivers/iio/adc/ade9000.c | 25 +++++++++++++------------
 1 file changed, 13 insertions(+), 12 deletions(-)

diff --git a/drivers/iio/adc/ade9000.c b/drivers/iio/adc/ade9000.c
index c6c3ea953fea..51cb43755a1f 100644
--- a/drivers/iio/adc/ade9000.c
+++ b/drivers/iio/adc/ade9000.c
@@ -1705,18 +1705,6 @@ static int ade9000_probe(struct spi_device *spi)
 	if (ret)
 		return ret;
 
-	ret = ade9000_request_irq(dev, "irq0", ade9000_irq0_thread, indio_dev);
-	if (ret)
-		return ret;
-
-	ret = ade9000_request_irq(dev, "irq1", ade9000_irq1_thread, indio_dev);
-	if (ret)
-		return ret;
-
-	ret = ade9000_request_irq(dev, "dready", ade9000_dready_thread, indio_dev);
-	if (ret)
-		return ret;
-
 	/* External CMOS clock input (optional - crystal can be used instead) */
 	st->clkin = devm_clk_get_optional_enabled(dev, NULL);
 	if (IS_ERR(st->clkin))
@@ -1736,6 +1724,19 @@ static int ade9000_probe(struct spi_device *spi)
 		return dev_err_probe(&spi->dev, ret,
 				     "Failed to get and enable vdd regulator\n");
 
+	/* Request IRQs only after powering the chip; the handlers do SPI access. */
+	ret = ade9000_request_irq(dev, "irq0", ade9000_irq0_thread, indio_dev);
+	if (ret)
+		return ret;
+
+	ret = ade9000_request_irq(dev, "irq1", ade9000_irq1_thread, indio_dev);
+	if (ret)
+		return ret;
+
+	ret = ade9000_request_irq(dev, "dready", ade9000_dready_thread, indio_dev);
+	if (ret)
+		return ret;
+
 	indio_dev->channels = ade9000_channels;
 	indio_dev->num_channels = ARRAY_SIZE(ade9000_channels);
 
-- 
2.43.0