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

Rajat Jain
2020-03-27T01:40:47Z

On Thu, Mar 26, 2020 at 2:20 PM Dmitry Torokhov
<dmitry.torokhov@gmail.com> wrote:
>
> Hi Rajat,
>
> On Tue, Mar 24, 2020 at 05:35:17AM -0700, Rajat Jain wrote:
> > 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;
>
> Why do we need to keep firmware-provided keymap in atkbd instance? It is
> not going anywhere and can be accessed via device_property_* API
> whenever we decide to refresh the keymap.

Done. I've sent out a new v3 patchset for review with this change.

>
> > };
> >
> > /*
> > @@ -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);
>
> This should be dev_dbg().

Done.

Thanks,

Rajat

>
> > + atkbd->use_fw_keymap = true;
> > + kfree(ptr);
> > + }
> > }
> >
> > /*
> > --
> > 2.25.1.696.g5e7596f4ac-goog
> >
>
> Thanks.
>
> --
> Dmitry