On 06/28/2013 01:52 AM, Gerhard Sittig wrote: > > [ late reply, just catching up with the backlog ] > > On Mon, Jun 24, 2013 at 17:26 -0600, Stephen Warren wrote: >> >> [ ... sparse matrices, not all columns/rows populated ... ] >> On some Tegra boards, there end up >> being rather tri-angular keymaps, where key positions (0, 0), (0, 1), >> (0, 2), (1, 1), (1, 2), (2, 2) end up being used. In this scenario, >> detailed investigation of the keymap would reveal: >> >> * Only scan columns 0..2 >> * For column 0, scan rows 0..2 >> * For column 1, scan rows 1..2 >> * For columm 2, scan row 2. > > That's another question I had. So far I was concerned with just > polling or scanning the relevant columns, while all the rows for > a given column were queried (as the driver always used to do). > > Now you raise the question of whether rows should get queried as > well depending on whether "a key may sit there". It wasn't the > exact question I raised, but I added a comment to the spot where > input subsystem events get generated: Is the driver expected to > emit events for matrix positions where no key map entry exists? I would assume there is no need to, but I don't know for sure. Perhaps Dmitry can answer that? -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
