[PATCH v2 4/5] Input: atkbd: Receive and use physcode->keycode mapping from FW

Rajat Jain
2020-03-24T12:35:49Z

Allow the firmware to specify the mapping between the physical
code and the linux keycode. This takes the form of a "keymap"
property which is an array of u32 values, each value specifying
mapping for a key.

Signed-off-by: Rajat Jain <rajatja@google.com>
---
v2: Remove the Change-Id from the commit log

drivers/input/keyboard/atkbd.c | 39 ++++++++++++++++++++++++++++++++--
1 file changed, 37 insertions(+), 2 deletions(-)

diff --git a/drivers/input/keyboard/atkbd.c b/drivers/input/keyboard/atkbd.c
index 7623eebef2593..c8017a5707581 100644
--- a/drivers/input/keyboard/atkbd.c
+++ b/drivers/input/keyboard/atkbd.c
@@ -66,6 +66,9 @@ MODULE_PARM_DESC(terminal, "Enable break codes on an IBM Terminal keyboard conne

#define MAX_FUNCTION_ROW_KEYS 24

+#define PHYSCODE(keymap) ((keymap >> 16) & 0xFFFF)
+#define KEYCODE(keymap) (keymap & 0xFFFF)
+
/*
* Scancode to keycode tables. These are just the default setting, and
* are loadable via a userland utility.
@@ -236,6 +239,9 @@ struct atkbd {

u16 function_row_physmap[MAX_FUNCTION_ROW_KEYS];
int num_function_row_keys;
+
+ unsigned short fw_keymap[ATKBD_KEYMAP_SIZE];
+ bool use_fw_keymap;
};

/*
@@ -1045,7 +1051,10 @@ static void atkbd_set_keycode_table(struct atkbd *atkbd)
memset(atkbd->keycode, 0, sizeof(atkbd->keycode));
bitmap_zero(atkbd->force_release_mask, ATKBD_KEYMAP_SIZE);

- if (atkbd->translated) {
+ if (atkbd->use_fw_keymap) {
+ memcpy(atkbd->keycode, atkbd->fw_keymap,
+ sizeof(atkbd->keycode));
+ } else if (atkbd->translated) {
for (i = 0; i < 128; i++) {
scancode = atkbd_unxlate_table[i];
atkbd->keycode[i] = atkbd_set2_keycode[scancode];
@@ -1163,7 +1172,9 @@ static void atkbd_parse_fwnode_data(struct serio *serio)
{
struct atkbd *atkbd = serio_get_drvdata(serio);
struct device *dev = &serio->dev;
- int n;
+ int i, n;
+ u32 *ptr;
+ u16 physcode, keycode;

if (!dev_fwnode(dev))
return;
@@ -1176,6 +1187,30 @@ static void atkbd_parse_fwnode_data(struct serio *serio)
atkbd->num_function_row_keys = n;
dev_info(dev, "FW reported %d function-row key locations\n", n);
}
+
+ /* Parse "keymap" property */
+ n = device_property_count_u32(dev, "keymap");
+ if (n > 0 && n <= ATKBD_KEYMAP_SIZE) {
+
+ ptr = kcalloc(n, sizeof(u32), GFP_KERNEL);
+ if (!ptr)
+ return;
+
+ if (device_property_read_u32_array(dev, "keymap", ptr, n)) {
+ dev_err(dev, "problem parsing FW keymap property\n");
+ kfree(ptr);
+ return;
+ }
+
+ for (i = 0; i < n; i++) {
+ physcode = PHYSCODE(ptr[i]);
+ keycode = KEYCODE(ptr[i]);
+ atkbd->fw_keymap[physcode] = keycode;
+ }
+ dev_info(dev, "Using FW keymap (%d keys)\n", n);
+ atkbd->use_fw_keymap = true;
+ kfree(ptr);
+ }
}

/*
--
2.25.1.696.g5e7596f4ac-goog