[PATCH 2/2] Input: matrix-keypad - Add device tree support

From: AnilKumar Ch
Date: Fri Oct 19 2012 - 03:06:21 EST


Add device tree support to matrix keypad driver and usage details
are added to device tree documentation. Driver was tested on AM335x
EVM.

Signed-off-by: AnilKumar Ch <anilkumar@xxxxxx>
---
.../devicetree/bindings/input/matrix-keypad.txt | 52 ++++++++++
drivers/input/keyboard/matrix_keypad.c | 104 +++++++++++++++++++-
2 files changed, 155 insertions(+), 1 deletion(-)
create mode 100644 Documentation/devicetree/bindings/input/matrix-keypad.txt

diff --git a/Documentation/devicetree/bindings/input/matrix-keypad.txt b/Documentation/devicetree/bindings/input/matrix-keypad.txt
new file mode 100644
index 0000000..50aaa6e
--- /dev/null
+++ b/Documentation/devicetree/bindings/input/matrix-keypad.txt
@@ -0,0 +1,52 @@
+* GPIO driven matrix keypad device tree bindings
+
+GPIO driven matrix keypad is used to interface a SoC with a matrix keypad.
+The matrix keypad supports multiple row and column lines, a key can be
+placed at each intersection of a unique row and a unique column. The matrix
+keypad can sense a key-press and key-release by means of GPIO lines and
+report the event using GPIO interrupts to the cpu.
+
+Required Properties:
+- compatible: Should be "matix-keypad"
+- keypad,num-row-gpios: Number of row lines connected to the keypad
+ controller.
+- keypad,num-col-gpios: Number of column lines connected to the keypad
+ controller.
+- row-gpios: List of gpios used as row lines. The gpio specifier
+ for this property depends on the gpio controller to
+ which these row lines are connected.
+- col-gpios: List of gpios used as column lines. The gpio specifier
+ for this property depends on the gpio controller to
+ which these column lines are connected.
+
+Optional Properties:
+- linux,no-autorepeat: do no enable autorepeat feature.
+- linux,wakeup: use any event on keypad as wakeup event.
+- debounce-delay-ms: debounce interval in milliseconds
+- col-scan-delay-us: delay, measured in microseconds, that is needed
+ before we can scan keypad after activating column gpio
+- clustered-irq: have clustered irq number
+- clustered-irq-flags: have clustered irq flags
+
+Example:
+ matrix-keypad {
+ compatible = "matrix-keypad";
+ keypad,num-row-gpios = <3>;
+ keypad,num-col-gpios = <2>;
+ debounce-delay-ms = <5>;
+ col-scan-delay-us = <2>;
+
+ row-gpios = <&gpio2 25 0
+ &gpio2 26 0
+ &gpio2 27 0>;
+
+ col-gpios = <&gpio2 21 0
+ &gpio2 22 0>;
+
+ linux,keymap = <0x0000008B
+ 0x0100009E
+ 0x02000069
+ 0x0001006A
+ 0x0101001C
+ 0x0201006C>;
+ };
diff --git a/drivers/input/keyboard/matrix_keypad.c b/drivers/input/keyboard/matrix_keypad.c
index 18b7237..39e480d 100644
--- a/drivers/input/keyboard/matrix_keypad.c
+++ b/drivers/input/keyboard/matrix_keypad.c
@@ -23,6 +23,9 @@
#include <linux/gpio.h>
#include <linux/input/matrix_keypad.h>
#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
+#include <linux/of_platform.h>

struct matrix_keypad {
const struct matrix_keypad_platform_data *pdata;
@@ -394,6 +397,91 @@ static void matrix_keypad_free_gpio(struct matrix_keypad *keypad)
gpio_free(pdata->col_gpios[i]);
}

+#ifdef CONFIG_OF
+static
+struct matrix_keypad_platform_data *matrix_keypad_parse_dt(struct device *dev)
+{
+ struct matrix_keypad_platform_data *pdata;
+ struct matrix_keymap_data *keymap_data;
+ struct device_node *np = dev->of_node;
+ struct property *prop;
+ int key_count = 0, length, row, col;
+ uint32_t *keymap;
+
+ pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
+ if (!pdata) {
+ dev_err(dev, "could not allocate memory for platform data\n");
+ return NULL;
+ }
+
+ of_property_read_u32(np, "keypad,num-row-gpios", &pdata->num_row_gpios);
+ of_property_read_u32(np, "keypad,num-col-gpios", &pdata->num_col_gpios);
+ if (!pdata->num_row_gpios || !pdata->num_col_gpios) {
+ dev_err(dev, "number of keypad rows/columns not specified\n");
+ return NULL;
+ }
+
+ keymap_data = devm_kzalloc(dev, sizeof(*keymap_data), GFP_KERNEL);
+ if (!keymap_data) {
+ dev_err(dev, "could not allocate memory for keymap data\n");
+ return NULL;
+ }
+ pdata->keymap_data = keymap_data;
+
+ prop = of_find_property(np, "linux,keymap", &length);
+ if (!prop)
+ return NULL;
+
+ key_count = length / sizeof(u32);
+ keymap_data->keymap_size = key_count;
+ keymap = devm_kzalloc(dev, sizeof(uint32_t) * key_count, GFP_KERNEL);
+ if (!keymap) {
+ dev_err(dev, "could not allocate memory for keymap\n");
+ return NULL;
+ }
+ keymap_data->keymap = keymap;
+
+ of_property_read_u32_array(np, "linux,keymap", keymap, key_count);
+
+ if (of_get_property(np, "linux,no-autorepeat", NULL))
+ pdata->no_autorepeat = true;
+ if (of_get_property(np, "linux,wakeup", NULL))
+ pdata->wakeup = true;
+ if (of_get_property(np, "gpio-activelow", NULL))
+ pdata->active_low = true;
+
+ of_property_read_u32(np, "debounce-delay-ms", &pdata->debounce_ms);
+ of_property_read_u32(np, "col-scan-delay-us",
+ &pdata->col_scan_delay_us);
+ of_property_read_u32(np, "clustered-irq", &pdata->clustered_irq);
+ of_property_read_u32(np, "clustered-irq-flags",
+ &pdata->clustered_irq_flags);
+
+ pdata->row_gpios = devm_kzalloc(dev, sizeof(unsigned int) *
+ pdata->num_row_gpios, GFP_KERNEL);
+ pdata->col_gpios = devm_kzalloc(dev, sizeof(unsigned int) *
+ pdata->num_col_gpios, GFP_KERNEL);
+ if (!pdata->row_gpios || !pdata->col_gpios) {
+ dev_err(dev, "could not allocate memory for gpios\n");
+ return NULL;
+ }
+
+ for (row = 0; row < pdata->num_row_gpios; row++)
+ pdata->row_gpios[row] = of_get_named_gpio(np, "row-gpios", row);
+
+ for (col = 0; col < pdata->num_col_gpios; col++)
+ pdata->col_gpios[col] = of_get_named_gpio(np, "col-gpios", col);
+
+ return pdata;
+}
+#else
+static
+struct matrix_keypad_platform_data *matrix_keypad_parse_dt(struct device *dev)
+{
+ return NULL;
+}
+#endif
+
static int __devinit matrix_keypad_probe(struct platform_device *pdev)
{
const struct matrix_keypad_platform_data *pdata;
@@ -404,7 +492,10 @@ static int __devinit matrix_keypad_probe(struct platform_device *pdev)
size_t keymap_size;
int err;

- pdata = pdev->dev.platform_data;
+ if (pdev->dev.of_node)
+ pdata = matrix_keypad_parse_dt(&pdev->dev);
+ else
+ pdata = pdev->dev.platform_data;
if (!pdata) {
dev_err(&pdev->dev, "no platform data defined\n");
return -EINVAL;
@@ -488,6 +579,16 @@ static int __devexit matrix_keypad_remove(struct platform_device *pdev)
return 0;
}

+#ifdef CONFIG_OF
+static const struct of_device_id matrix_keypad_dt_match[] = {
+ { .compatible = "matrix-keypad" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, matrix_keypad_dt_match);
+#else
+#define matrix_keypad_dt_match NULL
+#endif
+
static struct platform_driver matrix_keypad_driver = {
.probe = matrix_keypad_probe,
.remove = __devexit_p(matrix_keypad_remove),
@@ -495,6 +596,7 @@ static struct platform_driver matrix_keypad_driver = {
.name = "matrix-keypad",
.owner = THIS_MODULE,
.pm = &matrix_keypad_pm_ops,
+ .of_match_table = matrix_keypad_dt_match,
},
};
module_platform_driver(matrix_keypad_driver);
--
1.7.9.5

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/