Implemented sleep() in libposix using a busy-loop (temporarily).

Added LCDBar device implementation for the GrovePi driver.
Modified BroadcomI2C to use DEBUG() for several lines instead of NOTICE().
Added missing <String.h> in Device.h.

lib/libi2c/BroadcomI2C.cpp

@@ -40,16 +40,15 @@ BroadcomI2C::Result BroadcomI2C::initialize()
 
     // Detect I2C controller. In Qemu, the ClockDivider is always zero.
     if (m_io.read(ClockDivider) == 0)
-    {
-
+    {        
         return NotFound;
     }
 
     // Set a slow clock to attempt workaround the I2C bug in Broadcom 2835
     setClockDivider(0x5dc * 3);
-    NOTICE("I2C GPIO pins set");
-    NOTICE("ClockDivider is " << m_io.read(ClockDivider));
-    NOTICE("Status is " << m_io.read(Status));
+    DEBUG("I2C GPIO pins set");
+    DEBUG("ClockDivider is " << m_io.read(ClockDivider));
+    DEBUG("Status is " << m_io.read(Status));
 
     // Done
     return Success;

lib/libposix/unistd.h

@@ -298,6 +298,14 @@ extern C int chdir(const char *path);
  */
 extern C int unlink(const char *path);
 
+/**
+ * Sleep for the specified number of seconds.
+ *
+ * @param seconds Number of seconds to sleep
+ * @return Zero on success or number of seconds left when interrupted.
+ */
+extern C unsigned int sleep(unsigned int seconds);
+
 /**
  * @}
  */

lib/libposix/unistd/sleep.cpp

@@ -0,0 +1,25 @@
+/*
+ * Copyright (C) 2009 Niek Linnenbank
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <unistd.h>
+
+unsigned int sleep(unsigned int seconds)
+{
+    // TODO: kernel does not support sleep/wait scheduling yet.
+    // Temporary busy-loop implementation, which is inaccurate.
+    for (int i = 0; i < seconds * 1000000; i++);
+}

server/Device.h

@@ -20,6 +20,7 @@
 
 #include <Types.h>
 #include <errno.h>
+#include <String.h>
 
 /**
  * Abstract device class interface.

server/i2c/grovepi/LCDBar.cpp

@@ -0,0 +1,112 @@
+/*
+ * Copyright (C) 2015 Niek Linnenbank
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <unistd.h>
+#include "LCDBar.h"
+
+LCDBar::LCDBar(I2C *i2c)
+{
+    m_i2c = i2c;
+    m_identifier << "groveLCD";
+}
+
+Error LCDBar::initialize()
+{
+    return ESUCCESS;
+}
+
+Error LCDBar::write(s8 *buffer, Size size, Size offset)
+{
+    setRGB(0, 255, 0);
+    setText((const char *) buffer, size);
+    return size;
+}
+
+void LCDBar::textCommand(LCDBar::Command cmd)
+{
+    u8 command[2];
+
+    command[0] = 0x80;
+    command[1] = cmd;
+
+    m_i2c->setAddress(TextAddr);
+    m_i2c->write(command, sizeof(command));
+}
+
+void LCDBar::setText(const char *text, Size max)
+{
+    textCommand(ClearDisplay);
+    sleep(1);
+
+    textCommand(DisplayOn | NoCursor);
+    textCommand(DoubleLine);
+    sleep(1);
+
+    for (uint line = 0; line < 2; line++)
+    {
+        for (uint i = 0; i < 16; i++)
+        {
+            if (i + (line * 16) >= max)
+                return;
+
+            char v = text[i + (line * 16)];
+
+            if (!v)
+                return;
+            else if (v == '\n')
+            {
+                textCommand(Newline);
+                break;
+            }
+            else
+            {
+                u8 command[2];
+                command[0] = 0x40;
+                command[1] = v;
+                m_i2c->write(command, sizeof(command));
+            }
+        }
+    }
+}
+
+void LCDBar::setRGB(uint r, uint g, uint b)
+{
+    u8 command[2];
+    command[0] = 0;
+    command[1] = 0;
+    m_i2c->setAddress(0x62);
+    m_i2c->write(command, sizeof(command)); // 0,0
+
+    command[0] = 1;
+    m_i2c->write(command, sizeof(command)); // 1,0
+
+    command[0] = 0x8;
+    command[1] = 0xaa;
+    m_i2c->write(command, sizeof(command)); // 0x08,0xaa
+
+    command[0] = 4;
+    command[1] = r;
+    m_i2c->write(command, sizeof(command)); // 4,r
+
+    command[0] = 3;
+    command[1] = g;
+    m_i2c->write(command, sizeof(command)); // 3,g
+
+    command[0] = 2;
+    command[1] = b;
+    m_i2c->write(command, sizeof(command)); // 2,b
+}

server/i2c/grovepi/LCDBar.h

@@ -0,0 +1,105 @@
+/*
+ * Copyright (C) 2015 Niek Linnenbank
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __SERVER_I2C_GROVEPI_LCDBAR_H
+#define __SERVER_I2C_GROVEPI_LCDBAR_H
+
+/**     
+ * @defgroup groveDigi GrovePi LCD Bar
+ * @{
+ */
+
+#include <Macros.h>
+#include <Types.h>
+#include <Device.h>
+#include <I2C.h>
+
+/**
+ * @brief GrovePi LCD Bar
+ *
+ * @see https://github.com/DexterInd/GrovePi/blob/master/Firmware/Source/v1.2/grove_pi_v1_2_5/README.md
+ */
+class LCDBar : public Device
+{
+  private:
+
+    static const uint RGBAddr  = 0x62;
+    static const uint TextAddr = 0x3e;
+
+    /**
+     * LCDBar commands.
+     */
+    enum Command
+    {
+        ClearDisplay = 0x01,
+        NoCursor     = 0x04,
+        DisplayOn    = 0x08,
+        DoubleLine   = 0x28,
+        Newline      = 0xc0,
+        WriteChar    = 0x40
+    };
+
+  public:
+
+    /**
+     * @brief Constructor function.
+     */
+    LCDBar(I2C *i2c);
+
+    /**
+     * @brief Initializes the class.
+     *
+     * @return Error status code.
+     */
+    virtual Error initialize();
+
+    /** 
+     * @brief Set LCD Bar text.
+     *
+     * @param buffer Buffer to save the read bytes.
+     * @param size Number of bytes to read.
+     * @param offset Offset in the file to read.
+     * @return Number of bytes on success and ZERO on failure. 
+     */
+    virtual Error write(s8 *buffer, Size size, Size offset);
+
+  private:
+
+    /**
+     * Set LCD color.
+     */
+    void setRGB(uint r, uint g, uint b);
+
+    /**
+     * Set LCD text.
+     */
+    void setText(const char *text, Size max);
+
+    /**
+     * Send I2C text command.
+     */
+    void textCommand(Command cmd);
+
+    /** I2C controller */
+    I2C *m_i2c;
+};
+
+/**
+ * @}
+ */
+
+#endif /* __TIME_TIME_H */

server/i2c/grovepi/Main.cpp

@@ -23,45 +23,15 @@
 #include <KernelLog.h>
 #include "DigitalPort.h"
 #include "AnalogPort.h"
-
-#warning add to libposix with this dummy implementation.
-#define sleep(sec) for (int i = 0; i < 1000000; i++);
-
-void setRGB(BroadcomI2C *i2c, uint r, uint g, uint b)
-{
-    u8 command[2];
-    command[0] = 0;
-    command[1] = 0;
-    i2c->setAddress(0x62);
-    i2c->write(command, sizeof(command)); // 0,0
-
-    command[0] = 1;
-    i2c->write(command, sizeof(command)); // 1,0
-
-    command[0] = 0x8;
-    command[1] = 0xaa;
-    i2c->write(command, sizeof(command)); // 0x08,0xaa
-
-    command[0] = 4;
-    command[1] = r;
-    i2c->write(command, sizeof(command)); // 4,r
-
-    command[0] = 3;
-    command[1] = g;
-    i2c->write(command, sizeof(command)); // 3,g
-
-    command[0] = 2;
-    command[1] = b;
-    i2c->write(command, sizeof(command)); // 2,b
-}
+#include "LCDBar.h"
 
 int main(int argc, char **argv)
 {
     DeviceServer server(CharacterDeviceFile);
 
     // Setup logging
     Log *log = new KernelLog();
-    log->setMinimumLogLevel(Log::Debug);
+    log->setMinimumLogLevel(Log::Notice);
 
     // Initialize I2C controller
     BroadcomI2C *i2c = new BroadcomI2C();
@@ -80,35 +50,13 @@ int main(int argc, char **argv)
                 ERROR("failed to initialize I2C controller");
                 return EXIT_FAILURE;
         }
-        u8 command[4];
-
-        // Set RGB LED
-        setRGB(i2c, 0, 0, 255);
-        sleep(1);
 
-#if 0
-        // Send a version command to the GrovePi
-        command[0] = 8;
-        command[1] = 0;
-        command[2] = 0;
-        command[3] = 0;
-        i2c->setAddress(0x4);
-        i2c->write(command, sizeof(command));
-
-        // TODO: implement sleep
-        sleep(1);
-
-//        i2c->setAddress(0x4);
-//        i2c->read(command, 1);
+        // TODO: Provide /dev/i2c{0,1,2} and let the app set modes directly (TEMP fastest)
+        // or implement ioctl() support
+        // or /dev/grove/digi0/{mode | value | ...} with libfs / libdev (BEST)
 
-        i2c->setAddress(0x4);
-        i2c->read(command, sizeof(command));
-
-        // Ask firmware version
-        NOTICE("GrovePi firmware: " << command[1] << "." << command[2] << "." << command[3]);
-#endif
-#if 1
         // Set Digipin 3 to input mode
+        u8 command[4];
         command[0] = 5;
         command[1] = 3;
         command[2] = 0;
@@ -124,12 +72,6 @@ int main(int argc, char **argv)
         command[3] = 0;
         i2c->setAddress(0x4);
         i2c->write(command, sizeof(command));
-
-        //sleep(1);
-        //i2c->setAddress(0x4);
-        //i2c->read(command, 1);
-        //NOTICE("digi2: " << command[0]);
-#endif
     }
 
     // Add devices
@@ -139,6 +81,8 @@ int main(int argc, char **argv)
     for (int j = 0; j < 3; j++)
         server.add(new AnalogPort(i2c, j));
 
+    server.add(new LCDBar(i2c));
+
     // Start serving requests
     return server.run(argc, argv);
 }