From 8d149cd30f4fb3b47ffd3b2b4d34db101819fe02 Mon Sep 17 00:00:00 2001
From: Natalia Portillo <claunia@claunia.com>
Date: Fri, 30 Oct 2015 02:50:05 +0000
Subject: [PATCH] 	Implemented decoding mode page 04h.

---
 ChangeLog     |   5 ++
 SCSI/Modes.cs | 132 ++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 137 insertions(+)

diff --git a/ChangeLog b/ChangeLog
index 373fee0..b18420f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2015-10-30  Natalia Portillo  <claunia@claunia.com>
+
+	* SCSI/Modes.cs:
+	  Implemented decoding mode page 04h.
+
 2015-10-30  Natalia Portillo  <claunia@claunia.com>
 
 	* SCSI/Modes.cs:
diff --git a/SCSI/Modes.cs b/SCSI/Modes.cs
index 4804cf1..9acdefa 100644
--- a/SCSI/Modes.cs
+++ b/SCSI/Modes.cs
@@ -2285,6 +2285,138 @@ namespace DiscImageChef.Decoders.SCSI
             return sb.ToString();
         }
         #endregion Mode Page 0x01: Read-write error recovery page
+
+        #region Mode Page 0x04: Rigid disk drive geometry page
+        /// <summary>
+        /// Disconnect-reconnect page
+        /// Page code 0x04
+        /// 24 bytes in SCSI-2
+        /// </summary>
+        public struct ModePage_04
+        {
+            /// <summary>
+            /// Parameters can be saved
+            /// </summary>
+            public bool PS;
+            /// <summary>
+            /// Cylinders used for data storage
+            /// </summary>
+            public uint Cylinders;
+            /// <summary>
+            /// Heads for reading and/or writing
+            /// </summary>
+            public byte Heads;
+            /// <summary>
+            /// Cylinder where write precompensation starts
+            /// </summary>
+            public uint WritePrecompCylinder;
+            /// <summary>
+            /// Cylinder where write current reduction starts
+            /// </summary>
+            public uint WriteReduceCylinder;
+            /// <summary>
+            /// Step rate in 100 ns units
+            /// </summary>
+            public ushort DriveStepRate;
+            /// <summary>
+            /// Cylinder where the heads park
+            /// </summary>
+            public int LandingCylinder;
+            /// <summary>
+            /// Rotational position locking
+            /// </summary>
+            public byte RPL;
+            /// <summary>
+            /// Rotational skew to apply when synchronized
+            /// </summary>
+            public byte RotationalOffset;
+            /// <summary>
+            /// Medium speed in rpm
+            /// </summary>
+            public ushort MediumRotationRate;
+        }
+
+        public static ModePage_04? DecodeModePage_04(byte[] pageResponse)
+        {
+            if (pageResponse == null)
+                return null;
+
+            if ((pageResponse[0] & 0x3F) != 0x04)
+                return null;
+
+            if (pageResponse[1] + 2 != pageResponse.Length)
+                return null;
+
+            if (pageResponse.Length < 24)
+                return null;
+
+            ModePage_04 decoded = new ModePage_04();
+
+            decoded.PS |= (pageResponse[0] & 0x80) == 0x80;
+            decoded.Cylinders = (uint)((pageResponse[2] << 16) + (pageResponse[3] << 8) + pageResponse[4]);
+            decoded.Heads = pageResponse[5];
+            decoded.WritePrecompCylinder = (uint)((pageResponse[6] << 16) + (pageResponse[7] << 8) + pageResponse[8]);
+            decoded.WriteReduceCylinder = (uint)((pageResponse[9] << 16) + (pageResponse[10] << 8) + pageResponse[11]);
+            decoded.DriveStepRate = (ushort)((pageResponse[12] << 8) + pageResponse[13]);
+            decoded.LandingCylinder = ((pageResponse[14] << 16) + (pageResponse[15] << 8) + pageResponse[16]);
+            decoded.RPL = (byte)(pageResponse[17] & 0x03);
+            decoded.RotationalOffset = pageResponse[18];
+            decoded.MediumRotationRate = (ushort)((pageResponse[20] << 8) + pageResponse[21]);
+
+            return decoded;
+        }
+
+        public static string PrettifyModePage_04(byte[] pageResponse)
+        {
+            return PrettifyModePage_04(DecodeModePage_04(pageResponse));
+        }
+
+        public static string PrettifyModePage_04(ModePage_04? modePage)
+        {
+            if (!modePage.HasValue)
+                return null;
+
+            ModePage_04 page = modePage.Value;
+            StringBuilder sb = new StringBuilder();
+
+            sb.AppendLine("SCSI Rigid disk drive geometry page:");
+
+            if (page.PS)
+                sb.AppendLine("\tParameters can be saved");
+
+            sb.AppendFormat("\t{0} heads", page.Heads).AppendLine();
+            sb.AppendFormat("\t{0} cylinders", page.Cylinders).AppendLine();
+            if(page.WritePrecompCylinder < page.Cylinders)
+                sb.AppendFormat("\tWrite pre-compensation starts at cylinder {0}", page.WritePrecompCylinder).AppendLine();
+            if(page.WriteReduceCylinder < page.Cylinders)
+                sb.AppendFormat("\tWrite current reduction starts at cylinder {0}", page.WriteReduceCylinder).AppendLine();
+            if (page.DriveStepRate > 0)
+                sb.AppendFormat("\tDrive steps in {0} ns", (uint)page.DriveStepRate * 100).AppendLine();
+
+            sb.AppendFormat("\tHeads park in cylinder {0}", page.LandingCylinder).AppendLine();
+
+            if (page.MediumRotationRate > 0)
+                sb.AppendFormat("\tMedium rotates at {0} rpm", page.MediumRotationRate).AppendLine();
+
+            switch (page.RPL)
+            {
+                case 0:
+                    sb.AppendLine("\tSpindle synchronization is disable or unsupported");
+                    break;
+                case 1:
+                    sb.AppendLine("\tTarget operates as a synchronized-spindle slave");
+                    break;
+                case 2:
+                    sb.AppendLine("\tTarget operates as a synchronized-spindle master");
+                    break;
+                case 3:
+                    sb.AppendLine("\tTarget operates as a synchronized-spindle master control");
+                    break;
+            }
+
+            return sb.ToString();
+        }
+        #endregion Mode Page 0x04: Rigid disk drive geometry page
     }
 }