From cabd6e9cf22dc80544c3eb09c4169a05e94a6d3f Mon Sep 17 00:00:00 2001 From: David Wu Date: Tue, 10 Aug 2021 09:10:07 +0800 Subject: iio: adc: rockchip_saradc: add voltage notifier so get referenced voltage once at probe Add voltage notifier, no need to query regulator voltage for every saradc read, just get regulator voltage once at probe. Signed-off-by: David Wu Signed-off-by: Simon Xue Reviewed-by: Heiko Stuebner Link: https://lore.kernel.org/r/20210810011007.54066-1-xxm@rock-chips.com Signed-off-by: Jonathan Cameron --- drivers/iio/adc/rockchip_saradc.c | 47 +++++++++++++++++++++++++++++++++------ 1 file changed, 40 insertions(+), 7 deletions(-) (limited to 'drivers/iio') diff --git a/drivers/iio/adc/rockchip_saradc.c b/drivers/iio/adc/rockchip_saradc.c index f3eb8d2e50dc..a237fe469a30 100644 --- a/drivers/iio/adc/rockchip_saradc.c +++ b/drivers/iio/adc/rockchip_saradc.c @@ -49,10 +49,12 @@ struct rockchip_saradc { struct clk *clk; struct completion completion; struct regulator *vref; + int uv_vref; struct reset_control *reset; const struct rockchip_saradc_data *data; u16 last_val; const struct iio_chan_spec *last_chan; + struct notifier_block nb; }; static void rockchip_saradc_power_down(struct rockchip_saradc *info) @@ -105,13 +107,7 @@ static int rockchip_saradc_read_raw(struct iio_dev *indio_dev, mutex_unlock(&indio_dev->mlock); return IIO_VAL_INT; case IIO_CHAN_INFO_SCALE: - ret = regulator_get_voltage(info->vref); - if (ret < 0) { - dev_err(&indio_dev->dev, "failed to get voltage\n"); - return ret; - } - - *val = ret / 1000; + *val = info->uv_vref / 1000; *val2 = chan->scan_type.realbits; return IIO_VAL_FRACTIONAL_LOG2; default: @@ -298,6 +294,26 @@ out: return IRQ_HANDLED; } +static int rockchip_saradc_volt_notify(struct notifier_block *nb, + unsigned long event, + void *data) +{ + struct rockchip_saradc *info = + container_of(nb, struct rockchip_saradc, nb); + + if (event & REGULATOR_EVENT_VOLTAGE_CHANGE) + info->uv_vref = (unsigned long)data; + + return NOTIFY_OK; +} + +static void rockchip_saradc_regulator_unreg_notifier(void *data) +{ + struct rockchip_saradc *info = data; + + regulator_unregister_notifier(info->vref, &info->nb); +} + static int rockchip_saradc_probe(struct platform_device *pdev) { struct rockchip_saradc *info = NULL; @@ -410,6 +426,12 @@ static int rockchip_saradc_probe(struct platform_device *pdev) return ret; } + ret = regulator_get_voltage(info->vref); + if (ret < 0) + return ret; + + info->uv_vref = ret; + ret = clk_prepare_enable(info->pclk); if (ret < 0) { dev_err(&pdev->dev, "failed to enable pclk\n"); @@ -450,6 +472,17 @@ static int rockchip_saradc_probe(struct platform_device *pdev) if (ret) return ret; + info->nb.notifier_call = rockchip_saradc_volt_notify; + ret = regulator_register_notifier(info->vref, &info->nb); + if (ret) + return ret; + + ret = devm_add_action_or_reset(&pdev->dev, + rockchip_saradc_regulator_unreg_notifier, + info); + if (ret) + return ret; + return devm_iio_device_register(&pdev->dev, indio_dev); } -- cgit v1.2.3