[PATCH v1 1/1] iio: adc: meson: fix core clock enable/disable moment

From: George Stark
Date: Fri Jul 14 2023 - 15:03:41 EST


Enable core clock at probe stage and disable it at remove stage.
Core clock is responsible for turning on/off the entire SoC module so
it should be on before the first module register is touched and be off
at very last moment.

Signed-off-by: George Stark <gnstark@xxxxxxxxxxxxxx>
---
drivers/iio/adc/meson_saradc.c | 20 ++++++++++----------
1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/drivers/iio/adc/meson_saradc.c b/drivers/iio/adc/meson_saradc.c
index fe066c9fab83..5a5bb5cc1320 100644
--- a/drivers/iio/adc/meson_saradc.c
+++ b/drivers/iio/adc/meson_saradc.c
@@ -1055,12 +1055,6 @@ static int meson_sar_adc_hw_enable(struct iio_dev *indio_dev)
goto err_vref;
}

- ret = clk_prepare_enable(priv->core_clk);
- if (ret) {
- dev_err(dev, "failed to enable core clk\n");
- goto err_core_clk;
- }
-
regval = FIELD_PREP(MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK, 1);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK, regval);
@@ -1087,8 +1081,6 @@ static int meson_sar_adc_hw_enable(struct iio_dev *indio_dev)
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
MESON_SAR_ADC_REG3_ADC_EN, 0);
meson_sar_adc_set_bandgap(indio_dev, false);
- clk_disable_unprepare(priv->core_clk);
-err_core_clk:
regulator_disable(priv->vref);
err_vref:
meson_sar_adc_unlock(indio_dev);
@@ -1116,8 +1108,6 @@ static void meson_sar_adc_hw_disable(struct iio_dev *indio_dev)

meson_sar_adc_set_bandgap(indio_dev, false);

- clk_disable_unprepare(priv->core_clk);
-
regulator_disable(priv->vref);

if (!ret)
@@ -1420,6 +1410,12 @@ static int meson_sar_adc_probe(struct platform_device *pdev)
ARRAY_SIZE(meson_sar_adc_iio_channels);
}

+ ret = clk_prepare_enable(priv->core_clk);
+ if (ret) {
+ dev_err(dev, "failed to enable core clk\n");
+ goto err;
+ }
+
ret = meson_sar_adc_init(indio_dev);
if (ret)
goto err;
@@ -1445,17 +1441,21 @@ static int meson_sar_adc_probe(struct platform_device *pdev)
err_hw:
meson_sar_adc_hw_disable(indio_dev);
err:
+ clk_disable_unprepare(priv->core_clk);
return ret;
}

static int meson_sar_adc_remove(struct platform_device *pdev)
{
struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+ struct meson_sar_adc_priv *priv = iio_priv(indio_dev);

iio_device_unregister(indio_dev);

meson_sar_adc_hw_disable(indio_dev);

+ clk_disable_unprepare(priv->core_clk);
+
return 0;
}

--
2.38.4