mfd: qcom-i2c-pmic: add option to skip irq control

Some MFD PMIC configurations do not support interrupts. Make the interrupt
controller optional to support these PMIC configrations.

Without an interrupt controller this driver simply passes a regmap to
its children.

CRs-Fixed: 1037797
Change-Id: I52b909dd226494987c79ed106ffdf9892d966ef1
Signed-off-by: Nicholas Troast <ntroast@codeaurora.org>

2 files changed, 19 insertions, 14 deletions

diff --git a/Documentation/devicetree/bindings/mfd/qcom-i2c-pmic.txt b/Documentation/devicetree/bindings/mfd/qcom-i2c-pmic.txt
index 9c7c856ea42b..7e9aee1a96b3 100644
--- a/Documentation/devicetree/bindings/mfd/qcom-i2c-pmic.txt
+++ b/Documentation/devicetree/bindings/mfd/qcom-i2c-pmic.txt
@@ -32,29 +32,29 @@ Platform independent properties:
 	Definition: 7-bit I2C address of the device.
 
 - interrupt-parent
-	Usage:      required
+	Usage:      optional
 	Value type: <phandle>
 	Definition: phandle of the interrupt controller which services the
 		    summary interrupt.
 
 - interrupts
-	Usage:      required
+	Usage:      optional
 	Value type: <prop-encoded-array>
 	Definition: Summary interrupt specifier.
 
 - interrupt-controller
-	Usage:      required
+	Usage:      optional
 	Value type: <empty>
 	Definition: Boolean flag which indicates this device node is an
 		    interrupt controller.
 
 - #interrupt-cells
-	Usage:      required
+	Usage:      optional
 	Value type: <u32>
 	Definition: Number of cells to encode an interrupt source.
 
 - qcom,periph-map
-	Usage:      required
+	Usage:      optional
 	Value type: <prop-encoded-array>
 	Definition: A list of u32 arrays. This provides a mapping between the
 		    summary status register bits and peripheral addresses.
diff --git a/drivers/mfd/qcom-i2c-pmic.c b/drivers/mfd/qcom-i2c-pmic.c
index 4d0bdce755a6..9eb75d876577 100644
--- a/drivers/mfd/qcom-i2c-pmic.c
+++ b/drivers/mfd/qcom-i2c-pmic.c
@@ -58,7 +58,6 @@ struct i2c_pmic_periph {
 
 struct i2c_pmic {
 	struct device		*dev;
-	struct i2c_client	*client;
 	struct regmap		*regmap;
 	struct irq_domain	*domain;
 	struct i2c_pmic_periph	*periph;
@@ -497,25 +496,28 @@ static struct regmap_config i2c_pmic_regmap_config = {
 static int i2c_pmic_probe(struct i2c_client *client,
 			  const struct i2c_device_id *id)
 {
-	int rc;
 	struct i2c_pmic *chip;
+	int rc = 0;
 
 	chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
 	if (!chip)
 		return -ENOMEM;
 
+	chip->dev = &client->dev;
 	chip->regmap = devm_regmap_init_i2c(client, &i2c_pmic_regmap_config);
 	if (!chip->regmap)
 		return -ENODEV;
 
+	i2c_set_clientdata(client, chip);
+	if (!of_property_read_bool(chip->dev->of_node, "interrupt-controller"))
+		goto probe_children;
+
 	chip->domain = irq_domain_add_tree(client->dev.of_node,
 					   &i2c_pmic_domain_ops, chip);
-	if (!chip->domain)
-		return -ENOMEM;
-
-	chip->client = client;
-	chip->dev = &client->dev;
-	i2c_set_clientdata(client, chip);
+	if (!chip->domain) {
+		rc = -ENOMEM;
+		goto cleanup;
+	}
 
 	rc = i2c_pmic_parse_dt(chip);
 	if (rc < 0) {
@@ -549,6 +551,8 @@ static int i2c_pmic_probe(struct i2c_client *client,
 	}
 
 	enable_irq_wake(client->irq);
+
+probe_children:
 	of_platform_populate(chip->dev->of_node, NULL, NULL, chip->dev);
 	pr_info("I2C PMIC probe successful\n");
 	return rc;
@@ -565,7 +569,8 @@ static int i2c_pmic_remove(struct i2c_client *client)
 	struct i2c_pmic *chip = i2c_get_clientdata(client);
 
 	of_platform_depopulate(chip->dev);
-	irq_domain_remove(chip->domain);
+	if (chip->domain)
+		irq_domain_remove(chip->domain);
 	i2c_set_clientdata(client, NULL);
 	return 0;
 }