Mirroring commit 97ab802aa36f ("adc: meson-saradc: add support for getting reference voltage value") for meson-saradc, this adds support for getting the "vref-supply" regulator and register it as the ADC's reference voltage regulator, so clients can translate sampled ADC values to voltage.
Signed-off-by: Peter Cai peter@typeblog.net Reviewed-by: John Keeping john@metanate.com Tested-by: John Keeping john@metanate.com Cc: Simon Glass sjg@chromium.org Cc: Philipp Tomsich philipp.tomsich@vrull.eu Cc: Kever Yang kever.yang@rock-chips.com --- Changes in v2: - Reordered local variables in `rockchip_saradc_probe`. --- drivers/adc/rockchip-saradc.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+)
diff --git a/drivers/adc/rockchip-saradc.c b/drivers/adc/rockchip-saradc.c index e464d33f2267..4007188133c8 100644 --- a/drivers/adc/rockchip-saradc.c +++ b/drivers/adc/rockchip-saradc.c @@ -13,6 +13,7 @@ #include <asm/io.h> #include <linux/bitops.h> #include <linux/err.h> +#include <power/regulator.h>
#define SARADC_CTRL_CHN_MASK GENMASK(2, 0) #define SARADC_CTRL_POWER_CTRL BIT(3) @@ -100,8 +101,11 @@ int rockchip_saradc_stop(struct udevice *dev)
int rockchip_saradc_probe(struct udevice *dev) { + struct adc_uclass_plat *uc_pdata = dev_get_uclass_plat(dev); struct rockchip_saradc_priv *priv = dev_get_priv(dev); + struct udevice *vref; struct clk clk; + int vref_uv; int ret;
ret = clk_get_by_index(dev, 0, &clk); @@ -114,6 +118,23 @@ int rockchip_saradc_probe(struct udevice *dev)
priv->active_channel = -1;
+ ret = device_get_supply_regulator(dev, "vref-supply", &vref); + if (ret) { + printf("can't get vref-supply: %d\n", ret); + return ret; + } + + vref_uv = regulator_get_value(vref); + if (vref_uv < 0) { + printf("can't get vref-supply value: %d\n", vref_uv); + return vref_uv; + } + + /* VDD supplied by common vref pin */ + uc_pdata->vdd_supply = vref; + uc_pdata->vdd_microvolts = vref_uv; + uc_pdata->vss_microvolts = 0; + return 0; }