Reset ps/2 port should psmouse_probe fail before retrying

Filed a bug on this too:

https://bugzilla.kernel.org/show_bug.cgi?id=15780

This particular laptop will lose it's synaptics touch pad on return from suspend state. Reloading the psmouse module makes no difference. I came up with the attached work around which simply calls psmouse_reset on the port should the initial probe fail. This solves the problem for me and I've tested this on several laptops.

Initially discovered on Ubuntu 2.6.31 (karmic) and the problem continues to exist in lucid 2.6.32. I've filed a bug against ubuntu kernel here:

https://bugs.launchpad.net/oem-priority/+bug/551234

though the Ubuntu kernel team would really like to get upstream's input on the matter before accepting the patch. Please let me know what you think. Thanks.

Peter

index b407b35..d79eafc 100644
@@ -856,12 +856,12 @@ static const struct psmouse_protocol *psmouse_protocol_by_name(const char *name,
 	return NULL;
 }
 
-
 /*
- * psmouse_probe() probes for a PS/2 mouse.
+ * __psmouse_probe() probes for a PS/2 mouse.
+ * Wrapped by psmouse_probe() for clean reset code.
  */
 
-static int psmouse_probe(struct psmouse *psmouse)
+static int __psmouse_probe(struct psmouse *psmouse)
 {
 	struct ps2dev *ps2dev = &psmouse->ps2dev;
 	unsigned char param[2];

@@ -892,6 +892,23 @@ static int psmouse_probe(struct psmouse *psmouse)
 }
 
 /*
+ * Wrapper for probe routine to cleanly reset the device should
+ * the initial probe fail for any reason.
+ */
+static int psmouse_probe(struct psmouse *psmouse) {
+	struct ps2dev *ps2dev = &psmouse->ps2dev;
+	int i, ret = -1;
+
+	for (i=0; ((ret = __psmouse_probe(psmouse)) != 0) && i < 3; i++) {
+		printk(KERN_ERR "psmouse.c: Error encountered while probing"
+			" PS/2 device on %s, reseting.\n", ps2dev->serio->phys);
+		psmouse_reset(psmouse);
+	}
+
+	return ret;
+}
+
+/*
  * Here we set the mouse resolution.
  */
 

Hi,

Please send patches inline, not as attachments.
Use the full source file path in the patch.
Send the patch to [email protected] and cc: the Input subsystem maintainer.

typo: s/reseting/resetting/

Other than those 4 things, the patch looks OK to me. Well, we would prefer not to have the

	((ret = __psmouse_probe(psmouse)) != 0)

inside the for expression if possible. I.e., make the for(...) simpler.

Please read/review Documentation/SubmittingPatches. Thanks.

---
~Randy