[PATCH v3][RESEND] adp5061: Add support for battery charging enable

[Alexandru Ardelean]

From: Stefan Popa <stefan.popa@xxxxxxxxxx>

This patch adds the option to enable/disable battery charging. This
option is not configurable via the power_supply properties, therefore,
access via sysfs was provided to examine and modify this attribute on the
fly.

Signed-off-by: Stefan Popa <stefan.popa@xxxxxxxxxx>
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>
---

I could not find any traces about this patch being denied and why.
So this is a RESEND to [re]trigger a discussion if needed.

 .../ABI/testing/sysfs-class-power-adp5061     | 10 +++
 drivers/power/supply/adp5061.c                | 63 +++++++++++++++++++
 2 files changed, 73 insertions(+)
 create mode 100644 Documentation/ABI/testing/sysfs-class-power-adp5061

diff --git a/Documentation/ABI/testing/sysfs-class-power-adp5061 b/Documentation/ABI/testing/sysfs-class-power-adp5061
new file mode 100644
index 000000000000..0d056aa103b5
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-class-power-adp5061
@@ -0,0 +1,10 @@
+What: /sys/class/power_supply/adp5061/charging_enabled
+Description:
+	Enable/disable battery charging.
+
+	The ADP5061 charging function can be enabled by setting
+	this attribute to 1. See device datasheet for details.
+
+	Valid values:
+		- 1: enabled
+		- 0: disabled
diff --git a/drivers/power/supply/adp5061.c b/drivers/power/supply/adp5061.c
index 003557043ab3..6e09a6b710e8 100644
--- a/drivers/power/supply/adp5061.c
+++ b/drivers/power/supply/adp5061.c
@@ -74,6 +74,10 @@
 #define ADP5061_CHG_STATUS_2_RCH_LIM_INFO(x)	(((x) >> 3) & 0x1)
 #define ADP5061_CHG_STATUS_2_BAT_STATUS(x)	(((x) >> 0) & 0x7)
 
+/* ADP5061_FUNC_SET_1 */
+#define ADP5061_FUNC_SET_1_EN_CHG_MSK		BIT(0)
+#define ADP5061_FUNC_SET_1_EN_CHG_MODE(x)	(((x) & 0x01) << 0)
+
 /* ADP5061_IEND */
 #define ADP5061_IEND_IEND_MSK			GENMASK(7, 5)
 #define ADP5061_IEND_IEND_MODE(x)		(((x) & 0x07) << 5)
@@ -691,11 +695,64 @@ static const struct power_supply_desc adp5061_desc = {
 	.num_properties		= ARRAY_SIZE(adp5061_props),
 };
 
+static int adp5061_get_charging_enabled(struct device *dev,
+					struct device_attribute *attr,
+					char *buf)
+{
+	struct power_supply *psy = dev_get_drvdata(dev);
+	struct adp5061_state *st = power_supply_get_drvdata(psy);
+	unsigned int regval;
+	int ret;
+
+	ret = regmap_read(st->regmap, ADP5061_FUNC_SET_1, &regval);
+	if (ret < 0)
+		return ret;
+
+	regval &= ADP5061_FUNC_SET_1_EN_CHG_MSK;
+	return sprintf(buf, "%d\n", regval);
+}
+
+static int adp5061_set_charging_enabled(struct device *dev,
+					struct device_attribute *attr,
+					const char *buf, size_t count)
+{
+	struct power_supply *psy = dev_get_drvdata(dev);
+	struct adp5061_state *st = power_supply_get_drvdata(psy);
+	u8 chg_en;
+	int ret;
+
+	ret = kstrtou8(buf, 0, &chg_en);
+	if (ret < 0)
+		return ret;
+
+	ret = regmap_update_bits(st->regmap, ADP5061_FUNC_SET_1,
+				 ADP5061_FUNC_SET_1_EN_CHG_MSK,
+				 ADP5061_FUNC_SET_1_EN_CHG_MODE(!!chg_en));
+
+	if (ret < 0)
+		return ret;
+
+	return count;
+}
+
+static DEVICE_ATTR(charging_enabled, 0644, adp5061_get_charging_enabled,
+		   adp5061_set_charging_enabled);
+
+static struct attribute *adp5061_attributes[] = {
+	&dev_attr_charging_enabled.attr,
+	NULL
+};
+
+static const struct attribute_group adp5061_attr_group = {
+	.attrs = adp5061_attributes,
+};
+
 static int adp5061_probe(struct i2c_client *client,
 			 const struct i2c_device_id *id)
 {
 	struct power_supply_config psy_cfg = {};
 	struct adp5061_state *st;
+	int ret;
 
 	st = devm_kzalloc(&client->dev, sizeof(*st), GFP_KERNEL);
 	if (!st)
@@ -721,6 +778,12 @@ static int adp5061_probe(struct i2c_client *client,
 		return PTR_ERR(st->psy);
 	}
 
+	ret = sysfs_create_group(&st->psy->dev.kobj, &adp5061_attr_group);
+	if (ret < 0) {
+		dev_err(&client->dev, "failed to create sysfs group\n");
+		return ret;
+	}
+
 	return 0;
 }
 
-- 
2.20.1