[PATCH v3 4/5] Input: atkbd: Receive and use physcode->keycode mapping from FW

From: Rajat Jain
Date: Thu Mar 26 2020 - 21:33:01 EST


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@xxxxxxxxxx>
---
v3: Don't save the FW mapping in atkbd device.
v2: Remove the Change-Id from the commit log

drivers/input/keyboard/atkbd.c | 41 +++++++++++++++++++++++++++++++++-
1 file changed, 40 insertions(+), 1 deletion(-)

diff --git a/drivers/input/keyboard/atkbd.c b/drivers/input/keyboard/atkbd.c
index 3b20aba1861cd..0afa6d5aec3b4 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.
@@ -1032,6 +1035,38 @@ static unsigned int atkbd_oqo_01plus_scancode_fixup(struct atkbd *atkbd,
return code;
}

+static int atkbd_get_keymap_from_fwnode(struct atkbd *atkbd)
+{
+ struct device *dev = &atkbd->ps2dev.serio->dev;
+ int i, n;
+ u32 *ptr;
+ u16 physcode, keycode;
+
+ /* Parse "keymap" property */
+ n = device_property_count_u32(dev, "keymap");
+ if (n <= 0 || n > ATKBD_KEYMAP_SIZE)
+ return -ENXIO;
+
+ ptr = kcalloc(n, sizeof(u32), GFP_KERNEL);
+ if (!ptr)
+ return -ENOMEM;
+
+ if (device_property_read_u32_array(dev, "keymap", ptr, n)) {
+ dev_err(dev, "problem parsing FW keymap property\n");
+ kfree(ptr);
+ return -EINVAL;
+ }
+
+ memset(atkbd->keycode, 0, sizeof(atkbd->keycode));
+ for (i = 0; i < n; i++) {
+ physcode = PHYSCODE(ptr[i]);
+ keycode = KEYCODE(ptr[i]);
+ atkbd->keycode[physcode] = keycode;
+ }
+ kfree(ptr);
+ return 0;
+}
+
/*
* atkbd_set_keycode_table() initializes keyboard's keycode table
* according to the selected scancode set
@@ -1039,13 +1074,16 @@ static unsigned int atkbd_oqo_01plus_scancode_fixup(struct atkbd *atkbd,

static void atkbd_set_keycode_table(struct atkbd *atkbd)
{
+ struct device *dev = &atkbd->ps2dev.serio->dev;
unsigned int scancode;
int i, j;

memset(atkbd->keycode, 0, sizeof(atkbd->keycode));
bitmap_zero(atkbd->force_release_mask, ATKBD_KEYMAP_SIZE);

- if (atkbd->translated) {
+ if (!atkbd_get_keymap_from_fwnode(atkbd)) {
+ dev_dbg(dev, "Using FW keymap\n");
+ } else if (atkbd->translated) {
for (i = 0; i < 128; i++) {
scancode = atkbd_unxlate_table[i];
atkbd->keycode[i] = atkbd_set2_keycode[scancode];
@@ -1173,6 +1211,7 @@ static void atkbd_parse_fwnode_data(struct serio *serio)
atkbd->num_function_row_keys = n;
dev_dbg(dev, "FW reported %d function-row key locations\n", n);
}
+
}

/*
--
2.25.1.696.g5e7596f4ac-goog