On Mon, Jun 20, 2022 at 11:12:46PM -0500, Samuel Holland wrote:
> On 6/19/22 6:43 AM, Andy Shevchenko wrote:
> > On Sat, Jun 18, 2022 at 7:10 PM Samuel Holland <samuel@xxxxxxxxxxxx> wrote:
> >>
> >> The official Pine64 PinePhone keyboard case contains a matrix keypad and
> >> a MCU which runs a libre firmware. Add support for its I2C interface.
> >
> > ...
> >
> >> +#include <linux/crc8.h>
> >> +#include <linux/i2c.h>
> >> +#include <linux/input/matrix_keypad.h>
> >> +#include <linux/interrupt.h>
> >> +#include <linux/module.h>
> >> +#include <linux/regulator/consumer.h>
> >
> > Missed
> > types.h
> >
> > ...
> >
> >> +#define PPKB_ROWS 6
> >> +#define PPKB_COLS 12
> >
> > ...
> >
> >> + for (col = 0; col < PPKB_COLS; ++col) {
> >> + u8 old = old_buf[1 + col];
> >> + u8 new = new_buf[1 + col];
> >> + u8 changed = old ^ new;
> >> +
> >> + if (!changed)
> >> + continue;
> >> +
> >> + for (row = 0; row < PPKB_ROWS; ++row) {
> >> + u8 mask = BIT(row);
> >> + u8 value = new & mask;
> >> + unsigned short code;
> >> + bool fn_state;
> >> +
> >> + if (!(changed & mask))
> >> + continue;
> >> +
> >> + /*
> >> + * Save off the FN key state when the key was pressed,
> >> + * and use that to determine the code during a release.
> >> + */
> >> + fn_state = value ? ppkb->fn_pressed : ppkb->fn_state[col] & mask;
> >> + if (fn_state)
> >> + ppkb->fn_state[col] ^= mask;
> >
> > Can't it be converted to use bitmap APIs?
>
> This is a 2D matrix, with one byte per column, and one bit per row. There are
> only 6 rows, so two bits per byte are unused. Converting this to the bitmap API
> would unnecessarily complicate things.
We could have a constant bitmap masking the unused bits so they are
always skipped.
Anyway, I made a few edits and applied, we can continue improving the
driver in an iterative manner.
Thanks.
--
Dmitry
