Hi Shawn,
On Tue, Mar 26, 2013 at 12:36:41PM -0700, Shawn Nematbakhsh wrote:
> The trackpoint driver sets various parameter default values, all of
> which happen to be power-on defaults (Source: IBM TrackPoint Engineering
> Specification, Version 4.0. Also confirmed by empirical data).
>
> By sending the power-on reset command to reset all parameters to
> power-on state, we can skip the lengthy process of programming all
> parameters. In testing, ~2.5 secs of time writing parameters was reduced
> to .35 seconds waiting for power-on reset to complete.
>
> Signed-off-by: Shawn Nematbakhsh <sha...@chromium.org>
> ---
> drivers/input/mouse/trackpoint.c | 223
> +++++++++++++++++++++++++--------------
> drivers/input/mouse/trackpoint.h | 7 +-
> 2 files changed, 149 insertions(+), 81 deletions(-)
>
> diff --git a/drivers/input/mouse/trackpoint.c
> b/drivers/input/mouse/trackpoint.c
> index f310249..17e9b36 100644
> --- a/drivers/input/mouse/trackpoint.c
> +++ b/drivers/input/mouse/trackpoint.c
> @@ -20,6 +20,26 @@
> #include "trackpoint.h"
>
> /*
> + * Power-on Reset: Resets all trackpoint parameters, including RAM values,
> + * to defaults.
> + * Returns zero on success, non-zero on failure.
> + */
> +static int trackpoint_power_on_reset(struct ps2dev *ps2dev)
> +{
> + unsigned char results[2];
> +
> + if (ps2_command(ps2dev, NULL, MAKE_PS2_CMD(0, 0, TP_COMMAND)) ||
> + ps2_command(ps2dev, results, MAKE_PS2_CMD(0, 2, TP_POR))) {
> + return -1;
> + }
> +
> + /* POR response should be 0xAA00 or 0xFC00 */
> + if ((results[0] != 0xAA && results[0] != 0xFC) || results[1] != 0x00)
> + return -1;
I am a bit concerned about this. 0xfc00 indicates POR failure. In this
case shouldn't we try to reset the device, issue another POR and bail if
it fails again?
>
> static struct attribute *trackpoint_attrs[] = {
> &psmouse_attr_sensitivity.dattr.attr,
> @@ -179,6 +241,9 @@ static struct attribute *trackpoint_attrs[] = {
> &psmouse_attr_press_to_select.dattr.attr,
> &psmouse_attr_skipback.dattr.attr,
> &psmouse_attr_ext_dev.dattr.attr,
> + &psmouse_attr_twohand.dattr.attr,
> + &psmouse_attr_source_tag.dattr.attr,
> + &psmouse_attr_mb.dattr.attr,
What is the benefit of adding these 3 new attributes?
Thanks.
--
Dmitry
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