regulator: bd71837: Disable voltage monitoring for LDO3/4

There is a HW quirk in BD71837. The shutdown sequence timings for
bucks/LDOs which are enabled via register interface are changed.
At PMIC poweroff the voltage for BUCK6/7 is cut immediately at the
beginning of shut-down sequence. This causes LDO5/6 voltage
monitoring to detect under voltage and force PMIC to emergency
state instead of poweroff. Disable voltage monitoring for LDO5 and
LDO6 at probe to avoid this.

Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org

1 files changed, 19 insertions, 0 deletions

diff --git a/drivers/regulator/bd71837-regulator.c b/drivers/regulator/bd71837-regulator.c
index 0f8ac8dec3e1..a1bd8aaf4d98 100644
--- a/drivers/regulator/bd71837-regulator.c
+++ b/drivers/regulator/bd71837-regulator.c
@@ -569,6 +569,25 @@ static int bd71837_probe(struct platform_device *pdev)
 			BD71837_REG_REGLOCK);
 	}
 
+	/*
+	 * There is a HW quirk in BD71837. The shutdown sequence timings for
+	 * bucks/LDOs which are controlled via register interface are changed.
+	 * At PMIC poweroff the voltage for BUCK6/7 is cut immediately at the
+	 * beginning of shut-down sequence. As bucks 6 and 7 are parent
+	 * supplies for LDO5 and LDO6 - this causes LDO5/6 voltage
+	 * monitoring to errorneously detect under voltage and force PMIC to
+	 * emergency state instead of poweroff. In order to avoid this we
+	 * disable voltage monitoring for LDO5 and LDO6
+	 */
+	err = regmap_update_bits(pmic->mfd->regmap, BD718XX_REG_MVRFLTMASK2,
+				 BD718XX_LDO5_VRMON80 | BD718XX_LDO6_VRMON80,
+				 BD718XX_LDO5_VRMON80 | BD718XX_LDO6_VRMON80);
+	if (err) {
+		dev_err(&pmic->pdev->dev,
+			"Failed to disable voltage monitoring\n");
+		goto err;
+	}
+
 	for (i = 0; i < ARRAY_SIZE(pmic_regulator_inits); i++) {
 
 		struct regulator_desc *desc;