Hi Eric,

On Thu, May 7, 2009 at 2:18 PM, Eric Miao [off-list ref] wrote:

On Thu, May 7, 2009 at 4:41 PM, Trilok Soni [off-list ref] wrote:

quoted

Hi Eric,

On Thu, May 7, 2009 at 1:30 PM, Eric Miao [off-list ref] wrote:

quoted

Original patch by Marek Vasut, modified by Eric in:

1. use delayed work to simplify the debouncing
2. build keycode array for fast lookup
3. combine col_polarity/row_polarity into a single active_low field
(are there some cases where the GPIOs are externally connected
with an inverter and thus causing two different polarity requirement??)
4. use a generic bit array based XOR algorithm to detect key press/release,
which should make the column assertion time shorter and code a bit
cleaner
5. remove the ALT_FN handling, which is no way generic, the ALT_FN
key should be treated as no different from other keys, and translation
will be done by user space by commands like 'loadkeys'.

Patch tested on Littleton/PXA310 (though PXA310 has a dedicate keypad
controller, I have to configure those pins as generic GPIO to use this
driver, works quite well, though ;-)

Any support about removing/clearing ghost/phantom keys? Also we assume
that all gpios in the matrix should be able to generate interrupts so
no polldev support required.

Is there some info about such ghost/phantom keys? Otherwise I'll
assume these are something like sticky control keys?

I'm not sure if there're any such support in console tools and in
input subsystem. Hard to say...

And the comments below are of great value, I'll incorporate these
suggestions in later submission. Thanks very much.

Could you please have look at following gpio_matrix driver?

gpio_matrix.c:
http://android.git.kernel.org/?p=kernel/msm.git;a=blob;f=drivers/input/misc/gpio_matrix.c;h=c1f47651a4937d5c976a9625ca5da389dd7e4a7c;hb=HEAD

gpio_input.c:
http://android.git.kernel.org/?p=kernel/msm.git;a=blob;f=drivers/input/misc/gpio_input.c;h=7e307f267a2a059b64a3fb9c8a379b149016b2f8;hb=HEAD

-- 
---Trilok Soni
http://triloksoni.wordpress.com
http://www.linkedin.com/in/triloksoni