[PATCH 1/3] Input: imx_keypad - Add device tree support

[Ying.Liu@freescale.com (Liu Ying)]

This patch adds device tree support for imx keypad driver.
1) Basic device tree binding support.
2) Since the probe function needs keymap and keymap size
   information, we get them from device tree if it is
   supported, otherwise, we fall back to legacy platform data.
3) Support to configure keypad pins via pinctrl system.

Signed-off-by: Liu Ying <Ying.Liu@freescale.com>
---
 .../devicetree/bindings/input/imx-keypad.txt       |   54 +++++++++++++
 drivers/input/keyboard/imx_keypad.c                |   80 ++++++++++++++++++--
 2 files changed, 127 insertions(+), 7 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/input/imx-keypad.txt

diff --git a/Documentation/devicetree/bindings/input/imx-keypad.txt b/Documentation/devicetree/bindings/input/imx-keypad.txt
new file mode 100644
index 0000000..1c6e16d
--- /dev/null
+++ b/Documentation/devicetree/bindings/input/imx-keypad.txt
@@ -0,0 +1,54 @@
+* Freescale i.MX Keypad Port(KPP) device tree bindings
+
+The KPP is designed to interface with a keypad matrix with 2-point contact
+or 3-point contact keys. The KPP is designed to simplify the software task
+of scanning a keypad matrix. The KPP is capable of detecting, debouncing,
+and decoding one or multiple keys pressed simultaneously on a keypad.
+
+Required SoC Specific Properties:
+- compatible: Should be "fsl,imx-kpp".
+
+- reg: Physical base address of the KPP and length of memory mapped
+  region.
+
+- interrupts: The KPP interrupt number to the CPU(s).
+
+- clocks: The clock provided by the SoC to the KPP. Some SoCs use ipg clock,
+others use dummy clock(The clock for the KPP is provided by the SoCs
+automatically).
+
+Required Board Specific Properties:
+- pinctrl-names: The definition can be found at
+pinctrl/pinctrl-bindings.txt.
+
+- pinctrl-0: The definition can be found at
+pinctrl/pinctrl-bindings.txt.
+
+- linux,keymap: The definition can be found at
+bindings/input/matrix-keymap.txt.
+
+Example:
+kpp: kpp at 73f94000 {
+	compatible = "fsl,imx-kpp";
+	reg = <0x73f94000 0x4000>;
+	interrupts = <60>;
+	clocks = <&clks 0>;
+	pinctrl-names = "default";
+	pinctrl-0 = <&pinctrl_kpp_1>;
+	linux,keymap = <0x00000067	/* KEY_UP */
+			0x0001006c	/* KEY_DOWN */
+			0x00020072	/* KEY_VOLUMEDOWN */
+			0x00030066	/* KEY_HOME */
+			0x0100006a	/* KEY_RIGHT */
+			0x01010069	/* KEY_LEFT */
+			0x0102001c	/* KEY_ENTER */
+			0x01030073	/* KEY_VOLUMEUP */
+			0x02000040	/* KEY_F6 */
+			0x02010042	/* KEY_F8 */
+			0x02020043	/* KEY_F9 */
+			0x02030044	/* KEY_F10 */
+			0x0300003b	/* KEY_F1 */
+			0x0301003c	/* KEY_F2 */
+			0x0302003d	/* KEY_F3 */
+			0x03030074>;	/* KEY_POWER */
+};
diff --git a/drivers/input/keyboard/imx_keypad.c b/drivers/input/keyboard/imx_keypad.c
index 6d150e3..e4f5c6a 100644
--- a/drivers/input/keyboard/imx_keypad.c
+++ b/drivers/input/keyboard/imx_keypad.c
@@ -20,6 +20,8 @@
 #include <linux/jiffies.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
+#include <linux/of.h>
+#include <linux/pinctrl/consumer.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
 #include <linux/timer.h>
@@ -414,17 +416,76 @@ open_err:
 	return -EIO;
 }
 
+static struct of_device_id imx_keypad_of_match[] = {
+	{ .compatible = "fsl,imx-kpp", },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, imx_keypad_of_match);
+
+#ifdef CONFIG_OF
+static int imx_keypad_parse_dt(struct platform_device *pdev,
+			       uint32_t *keymap, int *keymap_size)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct device *dev = &pdev->dev;
+	unsigned int proplen, i;
+	const __be32 *prop;
+
+	if (!np)
+		return -ENODEV;
+
+	prop = of_get_property(np, "linux,keymap", &proplen);
+	if (!prop) {
+		dev_err(dev, "OF: linux,keymap property not defined in %s\n",
+				np->full_name);
+		return -ENOENT;
+	}
+
+	if (proplen % sizeof(u32)) {
+		dev_err(dev, "OF: Malformed keycode property in %s\n",
+				np->full_name);
+		return -EINVAL;
+	}
+
+	*keymap_size = proplen / sizeof(u32);
+	if (*keymap_size > MAX_MATRIX_KEY_NUM) {
+		dev_err(dev, "OF: linux,keymap size overflow\n");
+		return -EINVAL;
+	}
+
+	for (i = 0; i < *keymap_size; i++)
+		keymap[i] = be32_to_cpup(prop + i);
+
+	return 0;
+}
+#else
+static inline int imx_keypad_parse_dt(struct platform_device *pdev,
+				      uint32_t *keymap, int *keymap_size)
+{
+	return -ENODEV;
+}
+#endif
+
 static int imx_keypad_probe(struct platform_device *pdev)
 {
 	const struct matrix_keymap_data *keymap_data = pdev->dev.platform_data;
 	struct imx_keypad *keypad;
 	struct input_dev *input_dev;
 	struct resource *res;
-	int irq, error, i;
+	int irq, error, i, keymap_size = 0;
+	uint32_t keymap[MAX_MATRIX_KEY_NUM];
+	struct pinctrl *pinctrl;
 
-	if (keymap_data == NULL) {
-		dev_err(&pdev->dev, "no keymap defined\n");
-		return -EINVAL;
+	error = imx_keypad_parse_dt(pdev, keymap, &keymap_size);
+	if (error) {
+		if (keymap_data) {
+			keymap_size = keymap_data->keymap_size;
+			memcpy(keymap, keymap_data->keymap,
+					keymap_size * sizeof(keymap[0]));
+		} else {
+			dev_err(&pdev->dev, "no keymap defined\n");
+			return -EINVAL;
+		}
 	}
 
 	irq = platform_get_irq(pdev, 0);
@@ -473,6 +534,10 @@ static int imx_keypad_probe(struct platform_device *pdev)
 		goto failed_free_priv;
 	}
 
+	pinctrl = devm_pinctrl_get_select_default(&pdev->dev);
+	if (IS_ERR(pinctrl))
+		dev_warn(&pdev->dev, "failed to get default pinctrl\n");
+
 	keypad->clk = clk_get(&pdev->dev, NULL);
 	if (IS_ERR(keypad->clk)) {
 		dev_err(&pdev->dev, "failed to get keypad clock\n");
@@ -481,9 +546,9 @@ static int imx_keypad_probe(struct platform_device *pdev)
 	}
 
 	/* Search for rows and cols enabled */
-	for (i = 0; i < keymap_data->keymap_size; i++) {
-		keypad->rows_en_mask |= 1 << KEY_ROW(keymap_data->keymap[i]);
-		keypad->cols_en_mask |= 1 << KEY_COL(keymap_data->keymap[i]);
+	for (i = 0; i < keymap_size; i++) {
+		keypad->rows_en_mask |= 1 << KEY_ROW(keymap[i]);
+		keypad->cols_en_mask |= 1 << KEY_COL(keymap[i]);
 	}
 
 	if (keypad->rows_en_mask > ((1 << MAX_MATRIX_KEY_ROWS) - 1) ||
@@ -631,6 +696,7 @@ static struct platform_driver imx_keypad_driver = {
 		.name	= "imx-keypad",
 		.owner	= THIS_MODULE,
 		.pm	= &imx_kbd_pm_ops,
+		.of_match_table = of_match_ptr(imx_keypad_of_match),
 	},
 	.probe		= imx_keypad_probe,
 	.remove		= imx_keypad_remove,
-- 
1.7.1