The function keys in a keyboard's top row are usually intended for
certain actions such as "Browser back" and "Fullscreen".
As of now, when a top-row key is pressed, cros_ec_keyb sends function
key code (e.g. KEY_F1) instead of action key code (e.g. KEY_BACK) to
applications. Because `linux,keymap` defined in cros-ec-keyboard.dtsi
maps the scanlines of the top-row keys to the function key code.
Therefore, an application can only convert each function key to
different action based on a fixed mapping.
This patch aims to support a more flexible keyboard top-row design. If
a board specifies a custom layout for the top row keys in dt binding,
cros_ec_keyb will explicitly sends action key code to applications when
any top-row key is pressed, so the applications no longer have to make
assumptions.
Signed-off-by: Philip Chen <philipchen@xxxxxxxxxxxx>
---
drivers/input/keyboard/cros_ec_keyb.c | 71 +++++++++++++++++++++++++++
1 file changed, 71 insertions(+)
diff --git a/drivers/input/keyboard/cros_ec_keyb.c b/drivers/input/keyboard/cros_ec_keyb.c
index b379ed7628781..c997ec5c5d469 100644
--- a/drivers/input/keyboard/cros_ec_keyb.c
+++ b/drivers/input/keyboard/cros_ec_keyb.c
@@ -27,6 +27,34 @@
#include <asm/unaligned.h>
+#define MAX_NUM_TOP_ROW_KEYS 15
+
+/*
+ * Row/column (in the scan matrix) of the function keys (T1-T15)
+ * defined in Chrome OS keyboard spec
+ */
+static const struct key_pos {
+ u8 row;
+ u8 col;
+} top_row_key_pos[] = {
+ {.row = 0, .col = 2}, /* T1 */
+ {.row = 3, .col = 2}, /* T2 */
+ {.row = 2, .col = 2}, /* T3 */
+ {.row = 1, .col = 2}, /* T4 */
+ {.row = 3, .col = 4}, /* T5 */
+ {.row = 2, .col = 4}, /* T6 */
+ {.row = 1, .col = 4}, /* T7 */
+ {.row = 2, .col = 9}, /* T8 */
+ {.row = 1, .col = 9}, /* T9 */
+ {.row = 0, .col = 4}, /* T10 */
+ {.row = 0, .col = 1}, /* T11 */
+ {.row = 1, .col = 5}, /* T12 */
+ {.row = 3, .col = 5}, /* T13 */
+ {.row = 0, .col = 9}, /* T14 */
+ {.row = 0, .col = 11}, /* T15 */
+};
+BUILD_ASSERT(ARRAY_SIZE(top_row_key_pos) == MAX_NUM_TOP_ROW_KEYS);
+
/**
* struct cros_ec_keyb - Structure representing EC keyboard device
*
@@ -42,6 +70,7 @@
* @idev: The input device for the matrix keys.
* @bs_idev: The input device for non-matrix buttons and switches (or NULL).
* @notifier: interrupt event notifier for transport devices
+ * @num_function_row_keys: The number of top row keys in a custom keyboard
*/
struct cros_ec_keyb {
unsigned int rows;
@@ -58,6 +87,8 @@ struct cros_ec_keyb {
struct input_dev *idev;
struct input_dev *bs_idev;
struct notifier_block notifier;
+
+ uint8_t num_function_row_keys;
};
/**
@@ -511,6 +542,44 @@ static int cros_ec_keyb_register_bs(struct cros_ec_keyb *ckdev)
return 0;
}
+/**
+ * cros_ec_keyb_update_custom_keymap
+ *
+ * Update the keymap if the board has custom top row keys.
+ *
+ * @ckdev: The keyboard device
+ */
+
+static void cros_ec_keyb_update_custom_keymap(struct cros_ec_keyb *ckdev)
+{
+ u8 i;
+ u16 code;
+ u16 top_row_key_code[MAX_NUM_TOP_ROW_KEYS] = {0};
+ struct input_dev *idev = ckdev->idev;
+ unsigned short *keymap = idev->keycode;
+
+ if (of_property_read_variable_u16_array(ckdev->dev->of_node,
+ "google,custom-keyb-top-row",
+ top_row_key_code,
+ 0,
+ MAX_NUM_TOP_ROW_KEYS) > 0) {
+ for (i = 0; i < MAX_NUM_TOP_ROW_KEYS; i++) {
+ if (!top_row_key_code[i])
+ break;
+ code = MATRIX_SCAN_CODE(top_row_key_pos[i].row,
+ top_row_key_pos[i].col,
+ ckdev->row_shift);
+ /*
+ * Add the action key code for a top row key
+ * into the keymap.
+ */
+ keymap[code] = top_row_key_code[i];
+ __set_bit(keymap[code], idev->keybit);
+ }
+ ckdev->num_function_row_keys = i;
+ }
+}
+
/**
* cros_ec_keyb_register_bs - Register matrix keys
*
@@ -576,6 +645,8 @@ static int cros_ec_keyb_register_matrix(struct cros_ec_keyb *ckdev)
input_set_capability(idev, EV_MSC, MSC_SCAN);
input_set_drvdata(idev, ckdev);
ckdev->idev = idev;
+
+ cros_ec_keyb_update_custom_keymap(ckdev);
cros_ec_keyb_compute_valid_keys(ckdev);
err = input_register_device(ckdev->idev);
--
2.26.2
