gpio: mcp23s08: add support for mcp23018

This adds the required definitions for the mcp23018 which is the i2c
variant of the mcp23s18.
Signed-off-by: Phil Reid <preid@electromag.com.au>
Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/pinctrl-mcp23s08.c

@@ -25,6 +25,7 @@
 #define MCP_TYPE_008	2
 #define MCP_TYPE_017	3
 #define MCP_TYPE_S18    4
+#define MCP_TYPE_018    5
 
 #define MCP_MAX_DEV_PER_CS	8
 
@@ -834,6 +835,13 @@ static int mcp23s08_probe_one(struct mcp23s08 *mcp, struct device *dev,
 		mcp->chip.ngpio = 16;
 		mcp->chip.label = "mcp23017";
 		break;
+
+	case MCP_TYPE_018:
+		mcp->regmap = devm_regmap_init_i2c(data, &mcp23x17_regmap);
+		mcp->reg_shift = 1;
+		mcp->chip.ngpio = 16;
+		mcp->chip.label = "mcp23018";
+		break;
 #endif /* CONFIG_I2C */
 
 	default:
@@ -880,7 +888,7 @@ static int mcp23s08_probe_one(struct mcp23s08 *mcp, struct device *dev,
 		if (mirror)
 			status |= IOCON_MIRROR | (IOCON_MIRROR << 8);
 
-		if (type == MCP_TYPE_S18)
+		if (type == MCP_TYPE_S18 || type == MCP_TYPE_018)
 			status |= IOCON_INTCC | (IOCON_INTCC << 8);
 
 		ret = mcp_write(mcp, MCP_IOCON, status);
@@ -961,6 +969,10 @@ static const struct of_device_id mcp23s08_i2c_of_match[] = {
 		.compatible = "microchip,mcp23017",
 		.data = (void *) MCP_TYPE_017,
 	},
+	{
+		.compatible = "microchip,mcp23018",
+		.data = (void *) MCP_TYPE_018,
+	},
 /* NOTE: The use of the mcp prefix is deprecated and will be removed. */
 	{
 		.compatible = "mcp,mcp23008",
@@ -1010,6 +1022,7 @@ static int mcp230xx_probe(struct i2c_client *client,
 static const struct i2c_device_id mcp230xx_id[] = {
 	{ "mcp23008", MCP_TYPE_008 },
 	{ "mcp23017", MCP_TYPE_017 },
+	{ "mcp23018", MCP_TYPE_018 },
 	{ },
 };
 MODULE_DEVICE_TABLE(i2c, mcp230xx_id);