[PATCH] driver: mfd: admit rk805 driver registration without interrupt support

[Milo Spadacini]

rk805 use interrupt only for "rk808-rtc" and "rk805-pwrkey" drivers.
On custom board these drivers could be not used and the irq gpio
could be not connected.
Force the usage of a not used gpio, that could be floating, could cause
spurious interrupt.

Signed-off-by: Milo Spadacini <milo.spadacini at gmail.com>
---
 drivers/mfd/rk808.c | 39 +++++++++++++++++++++++++++------------
 1 file changed, 27 insertions(+), 12 deletions(-)

diff --git a/drivers/mfd/rk808.c b/drivers/mfd/rk808.c
index e00da7c7e3b1..ae33be90b312 100644
--- a/drivers/mfd/rk808.c
+++ b/drivers/mfd/rk808.c
@@ -643,6 +643,7 @@ MODULE_DEVICE_TABLE(of, rk808_of_match);
 static int rk808_probe(struct i2c_client *client,
 		       const struct i2c_device_id *id)
 {
+	struct irq_domain * rk808_irq_domain = NULL;
 	struct device_node *np = client->dev.of_node;
 	struct rk808 *rk808;
 	const struct rk808_reg_data *pre_init_reg;
@@ -692,7 +693,11 @@ static int rk808_probe(struct i2c_client *client,
 		pre_init_reg = rk805_pre_init_reg;
 		nr_pre_init_regs = ARRAY_SIZE(rk805_pre_init_reg);
 		cells = rk805s;
-		nr_cells = ARRAY_SIZE(rk805s);
+		if (client->irq)
+			nr_cells = ARRAY_SIZE(rk805s);
+		else
+			nr_cells = ARRAY_SIZE(rk805s) - 2;
+
 		break;
 	case RK808_ID:
 		rk808->regmap_cfg = &rk808_regmap_config;
@@ -734,19 +739,28 @@ static int rk808_probe(struct i2c_client *client,
 		return PTR_ERR(rk808->regmap);
 	}
 
-	if (!client->irq) {
+	if (client->irq) {
+
+		ret = regmap_add_irq_chip(rk808->regmap, client->irq,
+					  IRQF_ONESHOT, -1,
+					  rk808->regmap_irq_chip, &rk808->irq_data);
+		if (ret) {
+			dev_err(&client->dev, "Failed to add irq_chip %d\n", ret);
+			return ret;
+		}
+
+		rk808_irq_domain = regmap_irq_get_domain(rk808->irq_data);
+	}
+	else if (rk808->variant == RK805_ID)
+	{
+		dev_warn(&client->dev, "Skip interrupt support, no core IRQ\n");
+	}
+	else
+	{
 		dev_err(&client->dev, "No interrupt support, no core IRQ\n");
 		return -EINVAL;
 	}
 
-	ret = regmap_add_irq_chip(rk808->regmap, client->irq,
-				  IRQF_ONESHOT, -1,
-				  rk808->regmap_irq_chip, &rk808->irq_data);
-	if (ret) {
-		dev_err(&client->dev, "Failed to add irq_chip %d\n", ret);
-		return ret;
-	}
-
 	for (i = 0; i < nr_pre_init_regs; i++) {
 		ret = regmap_update_bits(rk808->regmap,
 					pre_init_reg[i].addr,
@@ -762,7 +776,7 @@ static int rk808_probe(struct i2c_client *client,
 
 	ret = devm_mfd_add_devices(&client->dev, PLATFORM_DEVID_NONE,
 			      cells, nr_cells, NULL, 0,
-			      regmap_irq_get_domain(rk808->irq_data));
+			      rk808_irq_domain);
 	if (ret) {
 		dev_err(&client->dev, "failed to add MFD devices %d\n", ret);
 		goto err_irq;
@@ -796,7 +810,8 @@ static void rk808_remove(struct i2c_client *client)
 {
 	struct rk808 *rk808 = i2c_get_clientdata(client);
 
-	regmap_del_irq_chip(client->irq, rk808->irq_data);
+	if (client->irq)
+		regmap_del_irq_chip(client->irq, rk808->irq_data);
 
 	/**
 	 * pm_power_off may points to a function from another module.
-- 
2.34.1