Add code to use libusb-1.0 asynchronous transfers to fix problem of

occasional missed keys and eliminate use of key_timeout which disrupts the
main loop timing (by M. Jones).

ChangeLog

@@ -20,6 +20,7 @@ v0.5dev (ongoing development)
  + glcd driver: new connection type 'serdisplib'
  + glcd driver: new connection type 'glcd2usb'
  * lcdproc client: On FreeBSD show only unique processes in 'S' screen
+ * picolcd: Use libusb-1.0 asynchronous transfers to fix missed keys (M. Jones)
 
 v0.5.5
  + sed1330 driver: Add support for HG25504 (L. Lagendijk)

LCDd.conf

@@ -926,6 +926,9 @@ Reboot=no
 ## Mini-box.com picoLCD (usblcd) driver ##
 [picolcd]
 
+# KeyTimeout is only used if the picoLCD driver is built with libusb-0.1. When
+# built with libusb-1.0 key and IR data is input asynchronously so there is no
+# need to wait for the USB data.
 # KeyTimeout is the time in ms that LCDd spends waiting for a key press before
 # cycling through other duties.  Higher values make LCDd use less CPU time and
 # make key presses more detectable.  Lower values make LCDd more responsive
@@ -933,6 +936,18 @@ Reboot=no
 # and a balanced value. [default: 500; legal: 0 - 1000]
 KeyTimeout=500
 
+# Key auto repeat is only available if the picoLCD driver is built with
+# libusb-1.0. Use KeyRepeatDelay and KeyRepeatInterval to configure key auto
+# repeat.
+#
+# Key auto repeat delay (time in ms from first key report to first repeat). Use
+# zero to disable auto repeat. [default: 300; legal: 0 - 3000]
+KeyRepeatDelay=300
+
+# Key auto repeat interval (time in ms between repeat reports). Only used if
+# KeyRepeatDelay is not zero. [default: 200; legal: 0 - 3000]
+KeyRepeatInterval=200
+
 # Sets the initial state of the backlight upon start-up.
 # [default: on; legal: on, off]
 #Backlight=on
@@ -948,6 +963,9 @@ Brightness=1000
 # Set the initial contrast [default: 1000; legal: 0 - 1000]
 Contrast=1000
 
+# Link the key lights to the backlight? [default: on; legal: on, off]
+#LinkLights=off
+
 # Light the keys? [default: on; legal: on, off]
 Keylights=on
 

acinclude.m4

@@ -381,6 +381,11 @@ dnl			else
 			if test "$enable_libusb" = yes ; then
 				DRIVERS="$DRIVERS picolcd${SO}"
 				actdrivers=["$actdrivers picolcd"]
+				if test "$enable_libusb_1_0" = yes ; then
+					AC_MSG_RESULT([The picolcd driver is using the libusb-1.0 library.])
+				else
+					AC_MSG_RESULT([The picolcd driver is using the libusb-0.1 library.])
+				fi
 			else
 				AC_MSG_WARN([The picolcd driver needs the libusb library.])
 			fi

configure.in

@@ -270,6 +270,29 @@ fi
 AC_SUBST(LIBUSB_LIBS)
 AC_SUBST(LIBUSB_CFLAGS)
 
+dnl ######################################################################
+dnl libusb-1.0 support
+dnl ######################################################################
+AC_MSG_CHECKING([if libusb-1-0 support has been enabled]);
+AC_ARG_ENABLE(libusb_1_0,
+	[AS_HELP_STRING([--disable-libusb-1-0],[disable USB support using libusb-1.0])],
+	[ if test "$enableval" != "no"; then
+		enable_libusb_1_0="yes"
+	fi ],
+	[ enable_libusb_1_0=yes ]
+)
+AC_MSG_RESULT($enable_libusb_1_0)
+
+if test "$enable_libusb_1_0" = "yes"; then
+	ifdef([PKG_CHECK_MODULES],
+		[PKG_CHECK_MODULES(LIBUSB_1_0, libusb-1.0 >= 1.0,
+			[AC_DEFINE(HAVE_LIBUSB_1_0, [1], [Define to 1 if you have libusb-1.0])],
+			[ enable_libusb_1_0=no ])],
+		[AC_MSG_WARN([pkg-config not (fully) installed; drivers requiring libusb-1.0 may not be built])])
+fi
+AC_SUBST(LIBUSB_1_0_LIBS)
+AC_SUBST(LIBUSB_1_0_CFLAGS)
+
 dnl ######################################################################
 dnl libftdi support
 dnl ######################################################################

docs/lcdproc-user/drivers/picolcd.docbook

@@ -56,7 +56,10 @@
 <para>
 	Finally, the picoLCD 20x2 (OEM) supports 8 general purpose outputs
 	and 10 custom splash screens.
-	Although these features are not supported by this driver, the
+	When the keypad is connected the outputs control the key LEDs. The
+	output command and KeyLight settings below can be used to control the
+	outputs.
+	Although splash screens are not supported by this driver, the
 	splash screens can be changed using the <command>usblcd</command>
 	tool, that can be built from the Linux SDK available on the picoLCD web page.
 </para>
@@ -115,7 +118,7 @@
   <para>
     The Brightness and OffBrightness settings only have an effect on the 20x4
     device. With the 20x2 device the backlight can only be set on (any value
-    greater than <literal>1000</literal>) or off (<literal>0</literal>).
+    <literal>1</literal> or greater) or off (<literal>0</literal>).
   </para>
 </note>
 
@@ -167,6 +170,15 @@
   </para></listitem>
 </varlistentry>
 
+<varlistentry>
+  <term>
+    <property>LinkLights</property> = &parameters.yesdefno;
+  </term>
+  <listitem><para>
+    Allow key LEDs to be turned on or off with the backlight. Default is <literal>yes</literal>.
+  </para></listitem>
+</varlistentry>
+
 <varlistentry>
   <term>
     <property>KeyLights</property> = &parameters.yesdefno;
@@ -243,14 +255,60 @@
     <property>KeyTimeout</property> =
     <parameter><replaceable>DURATION</replaceable></parameter>
   </term>
-  <listitem><para>
+  <listitem>
+  <para>
+    KeyTimeout is only used if the picoLCD driver is built with libusb-0.1, when
+    built with libusb-1.0 key and IR data is input asynchronously so there is no
+    need to wait for the USB data thus allowing LCDd to process other inputs at
+    the correct rate.
+  </para>
+  <para>
     This value controls how long <application>LCDd</application> waits for a key press when
     get_key() is called.  The value represents milliseconds and the default is <literal>500</literal>
     or .5 seconds.  Lowering this value will make LCDd more responsive but also causes LCDd to use
     more CPU time and, as the timeout grows shorter, key presses become harder to detect.
     Large values make key presses more reliable but may slow down LCDd. Values
     in the range <literal>0</literal>-<literal>1000</literal> (1s) are allowed.
-  </para></listitem>
+  </para>
+  </listitem>
+</varlistentry>
+
+<varlistentry>
+  <term>
+    <property>KeyRepeatDelay</property> =
+    <parameter><replaceable>DURATION</replaceable></parameter>
+  </term>
+  <listitem>
+  <para>
+    KeyRepeatDelay is only used if the picoLCD driver is built with libusb-1.0, when
+    built with libusb-0.1 key input blocks all other processing until the key is released.
+  </para>
+  <para>
+    This value controls how long <application>LCDd</application> waits from when a key is
+	pressed and reported before generating the first repeat.  The value represents milliseconds
+	and the default is <literal>300</literal> (0.3 second).  Use zero to disable auto repeat.
+	Values in the range <literal>0</literal>-<literal>3000</literal> (3s) are allowed.
+  </para>
+  </listitem>
+</varlistentry>
+
+<varlistentry>
+  <term>
+    <property>KeyRepeatInterval</property> =
+    <parameter><replaceable>DURATION</replaceable></parameter>
+  </term>
+  <listitem>
+  <para>
+    KeyRepeatInterval is only used if the picoLCD driver is built with libusb-1.0, when
+    built with libusb-0.1 key input blocks all other processing until the key is released.
+  </para>
+  <para>
+    This value controls how long <application>LCDd</application> waits between key reports
+	after generating the first repeat.  The value represents milliseconds and the default
+	is <literal>200</literal> (0.2 second). Use zero to disable auto repeat.
+	Values in the range <literal>0</literal>-<literal>3000</literal> (3s) are allowed.
+  </para>
+  </listitem>
 </varlistentry>
 
 <varlistentry>
@@ -320,6 +378,10 @@
 	deal with this in a sane way and toss out all key-up events for now.  The hardware is
 	touchy and both combo key-down and key-up actions may be reported as multiple events if
 	the user is more than a tenth of a second (maybe less?) off in motions.
+	The hardware is <emphasis>not</emphasis> "touchy" it reports what it receives. Two key
+	presses or releases may appear simultaneous to a human but they are always some time apart.
+	The hardware probably samples the keys for every USB transfer cycle; that is every 10ms,
+	significantly faster than the typical human response time of a few hundred milliseconds!
 </para>
 
 <sect3 id="picolcd-ir-status">

server/drivers/Makefile.am

@@ -32,7 +32,7 @@ i2500vfd_CFLAGS =    @LIBFTDI_CFLAGS@ $(AM_CFLAGS)
 IOWarrior_CFLAGS =   @LIBUSB_CFLAGS@ $(AM_CFLAGS)
 lis_CFLAGS =         @LIBUSB_CFLAGS@ @LIBFTDI_CFLAGS@ $(AM_CFLAGS)
 mdm166a_CFLAGS =     @LIBHID_CFLAGS@ $(AM_CFLAGS)
-picolcd_CFLAGS =     @LIBUSB_CFLAGS@ $(AM_CFLAGS)
+picolcd_CFLAGS =     @LIBUSB_CFLAGS@ @LIBUSB_1_0_CFLAGS@ $(AM_CFLAGS)
 shuttleVFD_CFLAGS =  @LIBUSB_CFLAGS@ $(AM_CFLAGS)
 ula200_CFLAGS =      @LIBFTDI_CFLAGS@ $(AM_CFLAGS)
 xosd_CFLAGS =        @LIBXOSD_CFLAGS@ $(AM_CFLAGS)
@@ -63,7 +63,7 @@ mtc_s16209x_LDADD =  libLCD.a
 MtxOrb_LDADD =       libLCD.a libbignum.a
 mx5000_LDADD =       @LIBMX5000@
 NoritakeVFD_LDADD =  libbignum.a
-picolcd_LDADD =      @LIBUSB_LIBS@ libLCD.a libbignum.a
+picolcd_LDADD =      @LIBUSB_LIBS@ @LIBUSB_1_0_LIBS@ libLCD.a libbignum.a
 pyramid_LDADD =      libLCD.a libbignum.a
 serialPOS_LDADD =    libbignum.a
 serialVFD_LDADD =    libLCD.a libbignum.a

server/drivers/picolcd.h

@@ -14,6 +14,14 @@
 #ifndef PICOLCD_H
 #define PCIOLCD_H
 
+#ifdef HAVE_LIBUSB_1_0
+# include <libusb.h>
+# define USB_DEVICE_HANDLE libusb_device_handle
+#else
+# include <usb.h>
+# define USB_DEVICE_HANDLE usb_dev_handle
+#endif
+
 /* 12 keys plus a 0 placeholder */
 #define KEYPAD_MAX		13
 #define KEYPAD_LIGHTS		8
@@ -34,7 +42,10 @@
 #define DEFAULT_OFFBRIGHTNESS	0    /* Off */
 #define DEFAULT_BACKLIGHT	1    /* On */
 #define DEFAULT_KEYLIGHTS	1    /* On */
+#define DEFAULT_LINKLIGHTS	1    /* On */
 #define DEFAULT_TIMEOUT		500  /* Half second */
+#define DEFAULT_REPEAT_DELAY 300	/* milliseconds */
+#define DEFAULT_REPEAT_INTERVAL 200	/* milliseconds */
 
 
 typedef struct _lcd_packet {
@@ -56,7 +67,7 @@ typedef struct _picolcd_device {
 	int width;                  /* width of lcd screen */
 	int height;                 /* height of lcd screen */
 	/* Pointer to function that writes data to the LCD format */
-	void (*write) (usb_dev_handle *lcd, const int row, const int col, const unsigned char *data);
+	void (*write) (USB_DEVICE_HANDLE *lcd, const int row, const int col, const unsigned char *data);
 	/* Pointer to function that defines a custom character */
 	void (*cchar) (Driver *drvthis, int n, unsigned char *dat);
 } picolcd_device;