[PATCH v4] Input: keyboard - add device tree bindings for simple key matrixes
Olof Johansson
olof at lixom.net
Wed Jan 4 08:37:28 EST 2012
This adds a simple device tree binding for simple key matrix data and
a helper to fill in the platform data.
The implementation is in a shared file outside if drivers/input/keyboard
since some drivers in drivers/input/misc might be making use of it
as well.
Changes since v3:
* Dropped compatible field in matrix-keymap.txt
* Dropped linux,fn-key
* Dropped linux,fn-keymap optional property but included guideline on
naming convention
* Now passing property name in to the helper function (or will assume
"linux,keymap" if passed NULL)
Changes since v2:
* Removed reference to "legacy" format with a subnode per key
* Changed to a packed format with one cell per key instead of 3.
* Moved new OF helper to separate file
* Misc fixups based on comments
Changes since v1:
* Removed samsung-style binding support
* Added linux,fn-keymap and linux,fn-key optional properties
Signed-off-by: Olof Johansson <olof at lixom.net>
---
.../devicetree/bindings/input/matrix-keymap.txt | 19 +++++
drivers/input/Kconfig | 4 +
drivers/input/Makefile | 1 +
drivers/input/keyboard/Kconfig | 1 +
drivers/input/of_keymap.c | 85 ++++++++++++++++++++
include/linux/input/matrix_keypad.h | 19 +++++
6 files changed, 129 insertions(+), 0 deletions(-)
create mode 100644 Documentation/devicetree/bindings/input/matrix-keymap.txt
create mode 100644 drivers/input/of_keymap.c
diff --git a/Documentation/devicetree/bindings/input/matrix-keymap.txt b/Documentation/devicetree/bindings/input/matrix-keymap.txt
new file mode 100644
index 0000000..3cd8b98
--- /dev/null
+++ b/Documentation/devicetree/bindings/input/matrix-keymap.txt
@@ -0,0 +1,19 @@
+A simple common binding for matrix-connected key boards. Currently targeted at
+defining the keys in the scope of linux key codes since that is a stable and
+standardized interface at this time.
+
+Required properties:
+- linux,keymap: an array of packed 1-cell entries containing the equivalent
+ of row, column and linux key-code. The 32-bit big endian cell is packed
+ as:
+ row << 24 | column << 16 | key-code
+
+Optional properties:
+Some users of this binding might choose to specify secondary keymaps for
+cases where there is a modifier key such as a Fn key. Proposed names
+for said properties are "linux,fn-keymap" or with another descriptive
+word for the modifier other from "Fn".
+
+Example:
+ linux,keymap = < 0x00030012
+ 0x0102003a >;
diff --git a/drivers/input/Kconfig b/drivers/input/Kconfig
index 001b147..3325979 100644
--- a/drivers/input/Kconfig
+++ b/drivers/input/Kconfig
@@ -25,6 +25,10 @@ config INPUT
if INPUT
+config INPUT_OF_MATRIX_KEYMAP
+ depends on USE_OF
+ bool
+
config INPUT_FF_MEMLESS
tristate "Support for memoryless force-feedback devices"
help
diff --git a/drivers/input/Makefile b/drivers/input/Makefile
index 0c78949..b173a13a 100644
--- a/drivers/input/Makefile
+++ b/drivers/input/Makefile
@@ -24,3 +24,4 @@ obj-$(CONFIG_INPUT_TOUCHSCREEN) += touchscreen/
obj-$(CONFIG_INPUT_MISC) += misc/
obj-$(CONFIG_INPUT_APMPOWER) += apm-power.o
+obj-$(CONFIG_INPUT_OF_MATRIX_KEYMAP) += of_keymap.o
diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
index cdc385b..3371954c 100644
--- a/drivers/input/keyboard/Kconfig
+++ b/drivers/input/keyboard/Kconfig
@@ -394,6 +394,7 @@ config KEYBOARD_NOMADIK
config KEYBOARD_TEGRA
tristate "NVIDIA Tegra internal matrix keyboard controller support"
depends on ARCH_TEGRA
+ select INPUT_OF_MATRIX_KEYMAP if USE_OF
help
Say Y here if you want to use a matrix keyboard connected directly
to the internal keyboard controller on Tegra SoCs.
diff --git a/drivers/input/of_keymap.c b/drivers/input/of_keymap.c
new file mode 100644
index 0000000..7f11f6d
--- /dev/null
+++ b/drivers/input/of_keymap.c
@@ -0,0 +1,85 @@
+/*
+ * Helpers for open firmware matrix keyboard bindings
+ *
+ * Copyright (C) 2012 Google, Inc
+ *
+ * Author:
+ * Olof Johansson <olof at lixom.net>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/input.h>
+#include <linux/of.h>
+#include <linux/input/matrix_keypad.h>
+#include <linux/export.h>
+#include <linux/gfp.h>
+#include <linux/slab.h>
+
+struct matrix_keymap_data *
+matrix_keyboard_of_fill_keymap(struct device_node *np, char *propname)
+{
+ struct matrix_keymap_data *kd;
+ int proplen = 0, i;
+ u32 *keymap;
+ const __be32 *prop;
+
+ if (!np)
+ return NULL;
+
+ if (!propname)
+ propname = "linux,keymap";
+
+ prop = of_get_property(np, propname, &proplen);
+
+ if (proplen % 4) {
+ pr_warn("Malformed keymap property %s in %s\n",
+ propname, np->full_name);
+ return NULL;
+ }
+
+ kd = kmalloc(sizeof(*kd), GFP_KERNEL);
+ if (!kd)
+ return NULL;
+ kd->keymap_size = proplen / sizeof(u32);
+
+ keymap = kzalloc(kd->keymap_size * sizeof(u32), GFP_KERNEL);
+ if (!keymap) {
+ kfree(kd);
+ return NULL;
+ }
+
+ kd->keymap = keymap;
+
+ for (i = 0; i < kd->keymap_size; i++) {
+ u32 tmp = be32_to_cpup(prop+i);
+ int key_code, row, col;
+
+ row = (tmp >> 24) & 0xff;
+ col = (tmp >> 16) & 0xff;
+ key_code = tmp & 0xffff;
+ *keymap++ = KEY(row, col, key_code);
+ }
+
+ return kd;
+}
+EXPORT_SYMBOL_GPL(matrix_keyboard_of_fill_keymap);
+
+void matrix_keyboard_of_free_keymap(const struct matrix_keymap_data *kd)
+{
+ if (!kd)
+ return;
+ kfree(kd->keymap);
+ kfree(kd);
+}
+EXPORT_SYMBOL_GPL(matrix_keyboard_of_free_keymap);
diff --git a/include/linux/input/matrix_keypad.h b/include/linux/input/matrix_keypad.h
index fe7c4b9..b54fd87 100644
--- a/include/linux/input/matrix_keypad.h
+++ b/include/linux/input/matrix_keypad.h
@@ -3,6 +3,7 @@
#include <linux/types.h>
#include <linux/input.h>
+#include <linux/of.h>
#define MATRIX_MAX_ROWS 32
#define MATRIX_MAX_COLS 32
@@ -106,4 +107,22 @@ matrix_keypad_build_keymap(const struct matrix_keymap_data *keymap_data,
__clear_bit(KEY_RESERVED, keybit);
}
+#ifdef CONFIG_INPUT_OF_MATRIX_KEYMAP
+struct matrix_keymap_data *
+matrix_keyboard_of_fill_keymap(struct device_node *np, char *propname);
+
+void matrix_keyboard_of_free_keymap(const struct matrix_keymap_data *kd);
+#else
+static inline struct matrix_keymap_data *
+matrix_keyboard_of_fill_keymap(struct device_node *np, char *propname)
+{
+ return NULL;
+}
+
+static inline void
+matrix_keyboard_of_free_keymap(const struct matrix_keymap_data *kd)
+{
+}
+#endif
+
#endif /* _MATRIX_KEYPAD_H */
--
1.7.8.GIT
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