gpio: mcp23s08: rename the device tree property

The device tree property should be more descriptive.
microchip seems more reasonable than mcp. The old mcp
prefix is still supported but marked as deprecated.
Users of mcp have to switch to the microchip prefix.
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Lars Poeschel <poeschel@lemonage.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Documentation/devicetree/bindings/gpio/gpio-mcp23s08.txt

@@ -3,10 +3,17 @@ Microchip MCP2308/MCP23S08/MCP23017/MCP23S17 driver for
 
 Required properties:
 - compatible : Should be
-    - "mcp,mcp23s08" for  8 GPIO SPI version
-    - "mcp,mcp23s17" for 16 GPIO SPI version
-    - "mcp,mcp23008" for  8 GPIO I2C version or
-    - "mcp,mcp23017" for 16 GPIO I2C version of the chip
+    - "mcp,mcp23s08" (DEPRECATED) for  8 GPIO SPI version
+    - "mcp,mcp23s17" (DEPRECATED) for 16 GPIO SPI version
+    - "mcp,mcp23008" (DEPRECATED) for  8 GPIO I2C version or
+    - "mcp,mcp23017" (DEPRECATED) for 16 GPIO I2C version of the chip
+
+    - "microchip,mcp23s08" for  8 GPIO SPI version
+    - "microchip,mcp23s17" for 16 GPIO SPI version
+    - "microchip,mcp23008" for  8 GPIO I2C version or
+    - "microchip,mcp23017" for 16 GPIO I2C version of the chip
+    NOTE: Do not use the old mcp prefix any more. It is deprecated and will be
+    removed.
 - #gpio-cells : Should be two.
   - first cell is the pin number
   - second cell is used to specify flags. Flags are currently unused.
@@ -15,10 +22,11 @@ Required properties:
         SPI uses this to specify the chipselect line which the chip is
         connected to. The driver and the SPI variant of the chip support
         multiple chips on the same chipselect. Have a look at
-        mcp,spi-present-mask below.
+        microchip,spi-present-mask below.
 
 Required device specific properties (only for SPI chips):
-- mcp,spi-present-mask : This is a present flag, that makes only sense for SPI
+- mcp,spi-present-mask (DEPRECATED)
+- microchip,spi-present-mask : This is a present flag, that makes only sense for SPI
         chips - as the name suggests. Multiple SPI chips can share the same
         SPI chipselect. Set a bit in bit0-7 in this mask to 1 if there is a
         chip connected with the corresponding spi address set. For example if
@@ -26,11 +34,13 @@ Required device specific properties (only for SPI chips):
         which is 0x08. mcp23s08 chip variant only supports bits 0-3. It is not
         possible to mix mcp23s08 and mcp23s17 on the same chipselect. Set at
         least one bit to 1 for SPI chips.
+    NOTE: Do not use the old mcp prefix any more. It is deprecated and will be
+    removed.
 - spi-max-frequency = The maximum frequency this chip is able to handle
 
 Example I2C:
 gpiom1: gpio@20 {
-        compatible = "mcp,mcp23017";
+        compatible = "microchip,mcp23017";
         gpio-controller;
         #gpio-cells = <2>;
         reg = <0x20>;
@@ -38,7 +48,7 @@ gpiom1: gpio@20 {
 
 Example SPI:
 gpiom1: gpio@0 {
-        compatible = "mcp,mcp23s17";
+        compatible = "microchip,mcp23s17";
         gpio-controller;
         #gpio-cells = <2>;
         spi-present-mask = <0x01>;

drivers/gpio/gpio-mcp23s08.c

@@ -483,10 +483,21 @@ static int mcp23s08_probe_one(struct mcp23s08 *mcp, struct device *dev,
 #ifdef CONFIG_SPI_MASTER
 static struct of_device_id mcp23s08_spi_of_match[] = {
 	{
-		.compatible = "mcp,mcp23s08", .data = (void *) MCP_TYPE_S08,
+		.compatible = "microchip,mcp23s08",
+		.data = (void *) MCP_TYPE_S08,
 	},
 	{
-		.compatible = "mcp,mcp23s17", .data = (void *) MCP_TYPE_S17,
+		.compatible = "microchip,mcp23s17",
+		.data = (void *) MCP_TYPE_S17,
+	},
+/* NOTE: The use of the mcp prefix is deprecated and will be removed. */
+	{
+		.compatible = "mcp,mcp23s08",
+		.data = (void *) MCP_TYPE_S08,
+	},
+	{
+		.compatible = "mcp,mcp23s17",
+		.data = (void *) MCP_TYPE_S17,
 	},
 	{ },
 };
@@ -496,10 +507,21 @@ MODULE_DEVICE_TABLE(of, mcp23s08_spi_of_match);
 #if IS_ENABLED(CONFIG_I2C)
 static struct of_device_id mcp23s08_i2c_of_match[] = {
 	{
-		.compatible = "mcp,mcp23008", .data = (void *) MCP_TYPE_008,
+		.compatible = "microchip,mcp23008",
+		.data = (void *) MCP_TYPE_008,
+	},
+	{
+		.compatible = "microchip,mcp23017",
+		.data = (void *) MCP_TYPE_017,
 	},
+/* NOTE: The use of the mcp prefix is deprecated and will be removed. */
 	{
-		.compatible = "mcp,mcp23017", .data = (void *) MCP_TYPE_017,
+		.compatible = "mcp,mcp23008",
+		.data = (void *) MCP_TYPE_008,
+	},
+	{
+		.compatible = "mcp,mcp23017",
+		.data = (void *) MCP_TYPE_017,
 	},
 	{ },
 };
@@ -620,10 +642,15 @@ static int mcp23s08_probe(struct spi_device *spi)
 	if (match) {
 		type = (int)match->data;
 		status = of_property_read_u32(spi->dev.of_node,
-				"mcp,spi-present-mask", &spi_present_mask);
+			    "microchip,spi-present-mask", &spi_present_mask);
 		if (status) {
-			dev_err(&spi->dev, "DT has no spi-present-mask\n");
-			return -ENODEV;
+			status = of_property_read_u32(spi->dev.of_node,
+				    "mcp,spi-present-mask", &spi_present_mask);
+			if (status) {
+				dev_err(&spi->dev,
+					"DT has no spi-present-mask\n");
+				return -ENODEV;
+			}
 		}
 		if ((spi_present_mask <= 0) || (spi_present_mask >= 256)) {
 			dev_err(&spi->dev, "invalid spi-present-mask\n");