Input: matrix-keypad - add device tree support

Also the driver was modifued to take advantage of recent improvements in
matrix_keypad_build_keymap() implementation, which automatically allocates
memory for keymap.

The driver was tested on AM335x EVM.

Signed-off-by: AnilKumar Ch <anilkumar@ti.com>
Acked-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

diff --git a/Documentation/devicetree/bindings/input/gpio-matrix-keypad.txt b/Documentation/devicetree/bindings/input/gpio-matrix-keypad.txt
new file mode 100644 (file)
index 0000000..ead641c
--- /dev/null
+++ b/Documentation/devicetree/bindings/input/gpio-matrix-keypad.txt
@@ -0,0 +1,46 @@
+* 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 "gpio-matrix-keypad"
+- 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.
+- linux,keymap:                The definition can be found at
+                       bindings/input/matrix-keymap.txt
+
+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
+
+Example:
+       matrix-keypad {
+               compatible = "gpio-matrix-keypad";
+               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..05d3a96 100644 (file)
--- 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;
@@ -37,8 +40,6 @@ struct matrix_keypad {
        bool scan_pending;
        bool stopped;
        bool gpio_all_disabled;
-
-       unsigned short keycodes[];
 };
 
 /*
@@ -118,6 +119,7 @@ static void matrix_keypad_scan(struct work_struct *work)
        struct matrix_keypad *keypad =
                container_of(work, struct matrix_keypad, work.work);
        struct input_dev *input_dev = keypad->input_dev;
+       const unsigned short *keycodes = input_dev->keycode;
        const struct matrix_keypad_platform_data *pdata = keypad->pdata;
        uint32_t new_state[MATRIX_MAX_COLS];
        int row, col, code;
@@ -153,7 +155,7 @@ static void matrix_keypad_scan(struct work_struct *work)
                        code = MATRIX_SCAN_CODE(row, col, keypad->row_shift);
                        input_event(input_dev, EV_MSC, MSC_SCAN, code);
                        input_report_key(input_dev,
-                                        keypad->keycodes[code],
+                                        keycodes[code],
                                         new_state[col] & (1 << row));
                }
        }
@@ -394,33 +396,95 @@ 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 * __devinit
+matrix_keypad_parse_dt(struct device *dev)
+{
+       struct matrix_keypad_platform_data *pdata;
+       struct device_node *np = dev->of_node;
+       unsigned int *gpios;
+       int i;
+
+       if (!np) {
+               dev_err(dev, "device lacks DT data\n");
+               return ERR_PTR(-ENODEV);
+       }
+
+       pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
+       if (!pdata) {
+               dev_err(dev, "could not allocate memory for platform data\n");
+               return ERR_PTR(-ENOMEM);
+       }
+
+       pdata->num_row_gpios = of_gpio_named_count(np, "row-gpios");
+       pdata->num_col_gpios = of_gpio_named_count(np, "col-gpios");
+       if (!pdata->num_row_gpios || !pdata->num_col_gpios) {
+               dev_err(dev, "number of keypad rows/columns not specified\n");
+               return ERR_PTR(-EINVAL);
+       }
+
+       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);
+
+       gpios = devm_kzalloc(dev,
+                            sizeof(unsigned int) *
+                               (pdata->num_row_gpios + pdata->num_col_gpios),
+                            GFP_KERNEL);
+       if (!gpios) {
+               dev_err(dev, "could not allocate memory for gpios\n");
+               return ERR_PTR(-ENOMEM);
+       }
+
+       for (i = 0; i < pdata->num_row_gpios; i++)
+               gpios[i] = of_get_named_gpio(np, "row-gpios", i);
+
+       for (i = 0; i < pdata->num_col_gpios; i++)
+               gpios[pdata->num_row_gpios + i] =
+                       of_get_named_gpio(np, "col-gpios", i);
+
+       pdata->row_gpios = gpios;
+       pdata->col_gpios = &gpios[pdata->num_row_gpios];
+
+       return pdata;
+}
+#else
+static inline struct matrix_keypad_platform_data *
+matrix_keypad_parse_dt(struct device *dev)
+{
+       dev_err(dev, "no platform data defined\n");
+
+       return ERR_PTR(-EINVAL);
+}
+#endif
+
 static int __devinit matrix_keypad_probe(struct platform_device *pdev)
 {
        const struct matrix_keypad_platform_data *pdata;
-       const struct matrix_keymap_data *keymap_data;
        struct matrix_keypad *keypad;
        struct input_dev *input_dev;
-       unsigned int row_shift;
-       size_t keymap_size;
        int err;
 
-       pdata = pdev->dev.platform_data;
+       pdata = dev_get_platdata(&pdev->dev);
        if (!pdata) {
-               dev_err(&pdev->dev, "no platform data defined\n");
-               return -EINVAL;
-       }
-
-       keymap_data = pdata->keymap_data;
-       if (!keymap_data) {
+               pdata = matrix_keypad_parse_dt(&pdev->dev);
+               if (IS_ERR(pdata)) {
+                       dev_err(&pdev->dev, "no platform data defined\n");
+                       return PTR_ERR(pdata);
+               }
+       } else if (!pdata->keymap_data) {
                dev_err(&pdev->dev, "no keymap data defined\n");
                return -EINVAL;
        }
 
-       row_shift = get_count_order(pdata->num_col_gpios);
-       keymap_size = (pdata->num_row_gpios << row_shift) *
-                       sizeof(keypad->keycodes[0]);
-       keypad = kzalloc(sizeof(struct matrix_keypad) + keymap_size,
-                        GFP_KERNEL);
+       keypad = kzalloc(sizeof(struct matrix_keypad), GFP_KERNEL);
        input_dev = input_allocate_device();
        if (!keypad || !input_dev) {
                err = -ENOMEM;
@@ -429,7 +493,7 @@ static int __devinit matrix_keypad_probe(struct platform_device *pdev)
 
        keypad->input_dev = input_dev;
        keypad->pdata = pdata;
-       keypad->row_shift = row_shift;
+       keypad->row_shift = get_count_order(pdata->num_col_gpios);
        keypad->stopped = true;
        INIT_DELAYED_WORK(&keypad->work, matrix_keypad_scan);
        spin_lock_init(&keypad->lock);
@@ -440,12 +504,14 @@ static int __devinit matrix_keypad_probe(struct platform_device *pdev)
        input_dev->open         = matrix_keypad_start;
        input_dev->close        = matrix_keypad_stop;
 
-       err = matrix_keypad_build_keymap(keymap_data, NULL,
+       err = matrix_keypad_build_keymap(pdata->keymap_data, NULL,
                                         pdata->num_row_gpios,
                                         pdata->num_col_gpios,
-                                        keypad->keycodes, input_dev);
-       if (err)
+                                        NULL, input_dev);
+       if (err) {
+               dev_err(&pdev->dev, "failed to build keymap\n");
                goto err_free_mem;
+       }
 
        if (!pdata->no_autorepeat)
                __set_bit(EV_REP, input_dev->evbit);
@@ -488,6 +554,14 @@ 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 = "gpio-matrix-keypad" },
+       { }
+};
+MODULE_DEVICE_TABLE(of, matrix_keypad_dt_match);
+#endif
+
 static struct platform_driver matrix_keypad_driver = {
        .probe          = matrix_keypad_probe,
        .remove         = __devexit_p(matrix_keypad_remove),
@@ -495,6 +569,7 @@ static struct platform_driver matrix_keypad_driver = {
                .name   = "matrix-keypad",
                .owner  = THIS_MODULE,
                .pm     = &matrix_keypad_pm_ops,
+               .of_match_table = of_match_ptr(matrix_keypad_dt_match),
        },
 };
 module_platform_driver(matrix_keypad_driver);