On Thu, 9 Sep 2021 15:33:31 +0300 Alexandru Ardelean <aardelean@xxxxxxxxxxx> wrote: > On Sun, 4 Jul 2021 at 20:59, Jonathan Cameron <jic23@xxxxxxxxxx> wrote: > > > > On Fri, 25 Jun 2021 10:43:25 +0300 > > Alexandru Ardelean <aardelean@xxxxxxxxxxx> wrote: > > > > > The driver tries to initialize all possible regulators from the DT, then > > > match the external regulators with each channel and then release all unused > > > regulators. > > > > > > We can change the logic a bit to initialize regulators only when at least > > > one channel needs them. > > > > > > This change creates a mx25_gcq_ext_regulator_setup() function that is > > > called only for the external regulators. If there's already a reference to > > > an external regulator, the function will just exit early with no error. > > > > > > This way, the driver doesn't need to keep any track of these regulators > > > during init. > > > > > > Signed-off-by: Alexandru Ardelean <aardelean@xxxxxxxxxxx> > > > > whilst I agree this is a bit cleaner, I definitely want to see review from > > those more familiar with the device before I take it! > > ping on this I'm not keen to have this fall through the cracks as it is a nice cleanup. So I've applied it. Note minor change as mentioned below. Applied to the togreg branch of iio.git and pushed out as testing for 0-day to see if it can find anything we missed. Thanks, Jonathan > > > > > Thanks, > > > > Jonathan > > > > > --- > > > drivers/iio/adc/fsl-imx25-gcq.c | 57 ++++++++++++++++----------------- > > > 1 file changed, 28 insertions(+), 29 deletions(-) > > > > > > diff --git a/drivers/iio/adc/fsl-imx25-gcq.c b/drivers/iio/adc/fsl-imx25-gcq.c > > > index ab5139e911c3..31776f80f847 100644 > > > --- a/drivers/iio/adc/fsl-imx25-gcq.c > > > +++ b/drivers/iio/adc/fsl-imx25-gcq.c > > > @@ -172,13 +172,37 @@ static const struct regmap_config mx25_gcq_regconfig = { > > > .reg_stride = 4, > > > }; > > > > > > +static int mx25_gcq_ext_regulator_setup(struct device *dev, > > > + struct mx25_gcq_priv *priv, u32 refp) > > > +{ > > > + char reg_name[12]; > > > + int ret; > > > + > > > + if (priv->vref[refp]) > > > + return 0; > > > + > > > + ret = snprintf(reg_name, sizeof(reg_name), "vref-%s", > > > + mx25_gcq_refp_names[refp]); > > > + if (ret < 0) > > > + return ret; > > > + > > > + priv->vref[refp] = devm_regulator_get_optional(dev, reg_name); > > > + if (IS_ERR(priv->vref[refp])) { Could be a deferred probe response so to avoid polluting log return dev_err_probe(dev, PTR_ERR(priv->vref[refp]), ...) > > > + dev_err(dev, > > > + "Error, trying to use external voltage reference without a %s regulator.", > > > + reg_name); > > > + return PTR_ERR(priv->vref[refp]); > > > + } > > > + > > > + return 0; > > > +} > > > + > > > static int mx25_gcq_setup_cfgs(struct platform_device *pdev, > > > struct mx25_gcq_priv *priv) > > > { > > > struct device_node *np = pdev->dev.of_node; > > > struct device_node *child; > > > struct device *dev = &pdev->dev; > > > - unsigned int refp_used[4] = {}; > > > int ret, i; > > > > > > /* > > > @@ -194,19 +218,6 @@ static int mx25_gcq_setup_cfgs(struct platform_device *pdev, > > > MX25_ADCQ_CFG_IN(i) | > > > MX25_ADCQ_CFG_REFN_NGND2); > > > > > > - /* > > > - * First get all regulators to store them in channel_vref_mv if > > > - * necessary. Later we use that information for proper IIO scale > > > - * information. > > > - */ > > > - priv->vref[MX25_ADC_REFP_INT] = NULL; > > > - priv->vref[MX25_ADC_REFP_EXT] = > > > - devm_regulator_get_optional(&pdev->dev, "vref-ext"); > > > - priv->vref[MX25_ADC_REFP_XP] = > > > - devm_regulator_get_optional(&pdev->dev, "vref-xp"); > > > - priv->vref[MX25_ADC_REFP_YP] = > > > - devm_regulator_get_optional(&pdev->dev, "vref-yp"); > > > - > > > for_each_child_of_node(np, child) { > > > u32 reg; > > > u32 refp = MX25_ADCQ_CFG_REFP_INT; > > > @@ -233,11 +244,10 @@ static int mx25_gcq_setup_cfgs(struct platform_device *pdev, > > > case MX25_ADC_REFP_EXT: > > > case MX25_ADC_REFP_XP: > > > case MX25_ADC_REFP_YP: > > > - if (IS_ERR(priv->vref[refp])) { > > > - dev_err(dev, "Error, trying to use external voltage reference without a vref-%s regulator.", > > > - mx25_gcq_refp_names[refp]); > > > + ret = mx25_gcq_ext_regulator_setup(&pdev->dev, priv, refp); > > > + if (ret) { > > > of_node_put(child); > > > - return PTR_ERR(priv->vref[refp]); > > > + return ret; > > > } > > > priv->channel_vref_mv[reg] = > > > regulator_get_voltage(priv->vref[refp]); > > > @@ -253,8 +263,6 @@ static int mx25_gcq_setup_cfgs(struct platform_device *pdev, > > > return -EINVAL; > > > } > > > > > > - ++refp_used[refp]; > > > - > > > /* > > > * Shift the read values to the correct positions within the > > > * register. > > > @@ -285,15 +293,6 @@ static int mx25_gcq_setup_cfgs(struct platform_device *pdev, > > > regmap_write(priv->regs, MX25_ADCQ_CR, > > > MX25_ADCQ_CR_PDMSK | MX25_ADCQ_CR_QSM_FQS); > > > > > > - /* Remove unused regulators */ > > > - for (i = 0; i != 4; ++i) { > > > - if (!refp_used[i]) { > > > - if (!IS_ERR_OR_NULL(priv->vref[i])) > > > - devm_regulator_put(priv->vref[i]); > > > - priv->vref[i] = NULL; > > > - } > > > - } > > > - > > > return 0; > > > } > > > > >