Messages in this thread | | | Date | Fri, 21 Jul 2023 12:58:49 +0300 | Subject | Re: [PATCH v1 1/1] iio: adc: meson: fix core clock enable/disable moment | From | George Stark <> |
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Hello Jonathan
Thanks for the feedback.
On 7/15/23 20:21, Jonathan Cameron wrote: > On Fri, 14 Jul 2023 22:03:15 +0300 > George Stark <gnstark@sberdevices.ru> wrote: > >> 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@sberdevices.ru> > > This sounds to me like this should perhaps have a fixes tag? ack > > Given where it is in the new sequence you can also use > devm_clk_get_enabled() though that makes a potential backport of > the fix trickier... > > I'd go with it anyway as it will make this change quite a bit simpler. ack > > More comments inline > > Jonathan > >> --- >> 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; > > If clk_prepare_enable() failed, then you shoudl not call clk_disable_unprepare() yes, but with devm_clk_get_enabled we dont't need this line anymore > >> + } >> + >> 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); > > Nothing to do with your patch, but this driver previously did some odd mixing > of direct returns and going to an empty label which definitely doesn't help > make this clear to follow. I made additional patch adding log messages to all errors those can break probe stage > >> 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; >> } >> >
-- Best regards George
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