[PATCH v2] mfd: as3722: disable auto power on when AC OK

[Marcel Ziswiler <marcel@ziswiler.com>]

From: Marcel Ziswiler <marcel.ziswiler@toradex.com>

On ams AS3722, power on when AC OK is enabled by default.
Making this option as disable by default and enable only
when platform need this explicitly.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Reviewed-by: Bibek Basu <bbasu@nvidia.com>
Tested-by: Bibek Basu <bbasu@nvidia.com>
Signed-off-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>

---

Changes in v2:
- Document device tree property as suggested by Stefan.
- Rename SEQ1 to SEQU1 as per datasheet as suggested by Stefan.
- Drop reference to downstream commit as suggested by Lee.

 Documentation/devicetree/bindings/mfd/as3722.txt |  2 ++
 drivers/mfd/as3722.c                             | 12 ++++++++++++
 include/linux/mfd/as3722.h                       |  3 +++
 3 files changed, 17 insertions(+)

diff --git a/Documentation/devicetree/bindings/mfd/as3722.txt b/Documentation/devicetree/bindings/mfd/as3722.txt
index 5297b2210704..2a665741d7fe 100644
--- a/Documentation/devicetree/bindings/mfd/as3722.txt
+++ b/Documentation/devicetree/bindings/mfd/as3722.txt
@@ -20,6 +20,8 @@ Optional properties:
 - ams,enable-internal-i2c-pullup: Boolean property, to enable internal pullup on
 	i2c scl/sda pins. Missing this will disable internal pullup on i2c
 	scl/sda lines.
+- ams,enable-ac-ok-power-on: Boolean property, to enable exit out of power off
+	mode with AC_OK pin (pin enabled in power off mode).
 
 Optional submodule and their properties:
 =======================================
diff --git a/drivers/mfd/as3722.c b/drivers/mfd/as3722.c
index f87342c211bc..4d069ed21ff6 100644
--- a/drivers/mfd/as3722.c
+++ b/drivers/mfd/as3722.c
@@ -349,6 +349,8 @@ static int as3722_i2c_of_probe(struct i2c_client *i2c,
 					"ams,enable-internal-int-pullup");
 	as3722->en_intern_i2c_pullup = of_property_read_bool(np,
 					"ams,enable-internal-i2c-pullup");
+	as3722->en_ac_ok_pwr_on = of_property_read_bool(np,
+					"ams,enable-ac-ok-power-on");
 	as3722->irq_flags = irqd_get_trigger_type(irq_data);
 	dev_dbg(&i2c->dev, "IRQ flags are 0x%08lx\n", as3722->irq_flags);
 	return 0;
@@ -360,6 +362,7 @@ static int as3722_i2c_probe(struct i2c_client *i2c,
 	struct as3722 *as3722;
 	unsigned long irq_flags;
 	int ret;
+	u8 val = 0;
 
 	as3722 = devm_kzalloc(&i2c->dev, sizeof(struct as3722), GFP_KERNEL);
 	if (!as3722)
@@ -398,6 +401,15 @@ static int as3722_i2c_probe(struct i2c_client *i2c,
 	if (ret < 0)
 		return ret;
 
+	if (as3722->en_ac_ok_pwr_on)
+		val = AS3722_CTRL_SEQU1_AC_OK_PWR_ON;
+	ret = as3722_update_bits(as3722, AS3722_CTRL_SEQU1_REG,
+			AS3722_CTRL_SEQU1_AC_OK_PWR_ON, val);
+	if (ret < 0) {
+		dev_err(as3722->dev, "CTRLsequ1 update failed: %d\n", ret);
+		return ret;
+	}
+
 	ret = devm_mfd_add_devices(&i2c->dev, -1, as3722_devs,
 				   ARRAY_SIZE(as3722_devs), NULL, 0,
 				   regmap_irq_get_domain(as3722->irq_data));
diff --git a/include/linux/mfd/as3722.h b/include/linux/mfd/as3722.h
index 51e6f9414575..b404a5af9bba 100644
--- a/include/linux/mfd/as3722.h
+++ b/include/linux/mfd/as3722.h
@@ -296,6 +296,8 @@
 #define AS3722_ADC1_CONV_NOTREADY			BIT(7)
 #define AS3722_ADC1_SOURCE_SELECT_MASK			0x1F
 
+#define AS3722_CTRL_SEQU1_AC_OK_PWR_ON			BIT(0)
+
 /* GPIO modes */
 #define AS3722_GPIO_MODE_MASK				0x07
 #define AS3722_GPIO_MODE_INPUT				0x00
@@ -391,6 +393,7 @@ struct as3722 {
 	unsigned long irq_flags;
 	bool en_intern_int_pullup;
 	bool en_intern_i2c_pullup;
+	bool en_ac_ok_pwr_on;
 	struct regmap_irq_chip_data *irq_data;
 };
 
-- 
2.14.4