iio:adc:twl6030: Enable measurement of VAC

stable inclusion
from stable-v5.10.168
commit 91ad3104b211e57842dc2289d2716589ced1affc
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I7URR4

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=91ad3104b211e57842dc2289d2716589ced1affc

----------------------------------------------------

[ Upstream commit bffb7d9d ]

VAC needs to be wired up to produce proper measurements,
without this change only near zero values are reported.
Reported-by: Nkernel test robot <lkp@intel.com>
Reported-by: NJulia Lawall <julia.lawall@lip6.fr>
Fixes: 1696f364 ("iio: twl6030-gpadc: TWL6030, TWL6032 GPADC driver")
Signed-off-by: NAndreas Kemnade <andreas@kemnade.info>
Link: https://lore.kernel.org/r/20221217221305.671117-1-andreas@kemnade.infoSigned-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: Nzhaoxiaoqiang11 <zhaoxiaoqiang11@jd.com>

drivers/iio/adc/twl6030-gpadc.c

@@ -952,7 +952,7 @@ static int twl6030_gpadc_probe(struct platform_device *pdev)
 	}
 
 	ret = twl_i2c_write_u8(TWL6030_MODULE_ID0,
-				VBAT_MEAS | BB_MEAS | BB_MEAS,
+				VBAT_MEAS | BB_MEAS | VAC_MEAS,
 				TWL6030_MISC1);
 	if (ret < 0) {
 		dev_err(dev, "failed to wire up inputs\n");