}
/*
- * This kills power to the touchpad; according to ALPS, current consumption
- * goes down to 50uA after running this. To turn power back on, we drive
- * MS-DAT low.
+ * This puts the touchpad in a power saving mode; according to ALPS, current
+ * consumption goes down to 50uA after running this. To turn power back on,
+ * we drive MS-DAT low. Measuring with a 1mA resolution ammeter says that
+ * the current on the SUS_3.3V rail drops from 3mA or 4mA to 0 when we do this.
+ *
+ * We have no formal spec that details this operation -- the low-power
+ * sequence came from a long-lost email trail.
*/
-static int hgpk_toggle_power(struct psmouse *psmouse, int enable)
+static int hgpk_toggle_powersave(struct psmouse *psmouse, int enable)
{
struct ps2dev *ps2dev = &psmouse->ps2dev;
int timeo;
* the controller. Once we get an ACK back from it, it
* means we can continue with the touchpad re-init. ALPS
* tells us that 1s should be long enough, so set that as
- * the upper bound.
+ * the upper bound. (in practice, it takes about 3 loops.)
*/
for (timeo = 20; timeo > 0; timeo--) {
if (!ps2_sendbyte(&psmouse->ps2dev,
PSMOUSE_CMD_DISABLE, 20))
break;
- msleep(50);
+ msleep(25);
}
err = hgpk_reset_device(psmouse, false);
/* should be all set, enable the touchpad */
ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_ENABLE);
psmouse_set_state(psmouse, PSMOUSE_ACTIVATED);
-
+ hgpk_dbg(psmouse, "Touchpad powered up.\n");
} else {
hgpk_dbg(psmouse, "Powering off touchpad.\n");
- psmouse_set_state(psmouse, PSMOUSE_IGNORE);
if (ps2_command(ps2dev, NULL, 0xec) ||
ps2_command(ps2dev, NULL, 0xec) ||
return -1;
}
+ psmouse_set_state(psmouse, PSMOUSE_IGNORE);
+
/* probably won't see an ACK, the touchpad will be off */
ps2_sendbyte(&psmouse->ps2dev, 0xec, 20);
}
static int hgpk_reconnect(struct psmouse *psmouse)
{
+ struct hgpk_data *priv = psmouse->private;
+
/*
* During suspend/resume the ps2 rails remain powered. We don't want
* to do a reset because it's flush data out of buffers; however,
PM_EVENT_ON)
return 0;
+ priv->powered = 1;
return hgpk_reset_device(psmouse, false);
}
* hgpk_toggle_power will deal w/ state so
* we're not racing w/ irq
*/
- err = hgpk_toggle_power(psmouse, value);
+ err = hgpk_toggle_powersave(psmouse, value);
if (!err)
priv->powered = value;
}