ibasso: Implement proper PIVOT_ROOT filesystem access

Including direct use of the external SD card mount

Known issue:  If SD card is inserted at startup, it must be
              ejected and reinserted to be registered.

Change-Id: I5f420160bda32135cbb088c1e8b04b6e3a73018e

firmware/export/config/ibassodx50.h

@@ -140,9 +140,14 @@
 /* Define this if a programmable hotkey is mapped */
 #define HAVE_HOTKEY
 
-/* No special storage */
+/* Supports internal and microSD storage */
-#define CONFIG_STORAGE STORAGE_HOSTFS
+#define CONFIG_STORAGE (STORAGE_HOSTFS|STORAGE_SD)
+#define HOSTFS_VOL_DEC "Internal"
 #define HAVE_STORAGE_FLUSH
+#define HAVE_MULTIDRIVE  /* But _not_ CONFIG_STORAGE_MULTI */
+#define NUM_DRIVES 2
+#define HAVE_HOTSWAP
+#define MULTIDRIVE_DIR "/mnt/external_sd"
 
 /* More common stuff */
 #define BATTERY_DEV_NAME "battery"

firmware/export/config/ibassodx90.h

@@ -137,9 +137,14 @@
 /* Define this if a programmable hotkey is mapped */
 #define HAVE_HOTKEY
 
-/* No special storage */
+/* Supports internal and microSD storage */
-#define CONFIG_STORAGE STORAGE_HOSTFS
+#define CONFIG_STORAGE (STORAGE_HOSTFS|STORAGE_SD)
+#define HOSTFS_VOL_DEC "Internal"
 #define HAVE_STORAGE_FLUSH
+#define HAVE_MULTIDRIVE  /* But _not_ CONFIG_STORAGE_MULTI */
+#define NUM_DRIVES 2
+#define HAVE_HOTSWAP
+#define MULTIDRIVE_DIR "/mnt/external_sd"
 
 /* More common stuff */
 #define BATTERY_DEV_NAME "battery"

firmware/target/hosted/ibasso/system-ibasso.c

@@ -28,6 +28,7 @@
 
 #include "config.h"
 #include "debug.h"
+#include "mv.h"
 
 #include "button-ibasso.h"
 #include "debug-ibasso.h"
@@ -39,6 +40,8 @@
 uintptr_t* stackbegin;
 uintptr_t* stackend;
 
+/* forward-declare */
+bool os_file_exists(const char *ospath);
 
 void system_init(void)
 {
@@ -95,3 +98,55 @@ void system_exception_wait(void)
 
     while(1) {};
 }
+
+bool hostfs_removable(IF_MD_NONVOID(int drive))
+{
+#ifdef HAVE_MULTIDRIVE
+    if (drive > 0)
+        return true;
+    else
+#endif
+        return false; /* internal: always present */
+}
+
+#ifdef HAVE_MULTIDRIVE
+int volume_drive(int drive)
+{
+    return drive;
+}
+#endif /* HAVE_MULTIDRIVE */
+
+#ifdef CONFIG_STORAGE_MULTI
+int hostfs_driver_type(int drive)
+{
+    return drive > 0 ? STORAGE_SD_NUM : STORAGE_HOSTFS_NUM;
+}
+#endif /* CONFIG_STORAGE_MULTI */
+
+bool hostfs_present(IF_MD_NONVOID(int drive))
+{
+#ifdef HAVE_MULTIDRIVE
+    if (drive > 0)
+#if defined(MULTIDRIVE_DEV)
+        return os_file_exists(MULTIDRIVE_DEV);
+#else
+        return extsd_present;
+#endif
+    else
+#endif
+        return true; /* internal: always present */
+}
+
+#ifdef HAVE_HOTSWAP
+bool volume_removable(int volume)
+{
+    /* don't support more than one partition yet, so volume == drive */
+    return hostfs_removable(volume);
+}
+
+bool volume_present(int volume)
+{
+    /* don't support more than one partition yet, so volume == drive */
+    return hostfs_present(volume);
+}
+#endif

firmware/target/hosted/ibasso/vold-ibasso.c

@@ -45,7 +45,6 @@
 static const char VOLD_MONITOR_SOCKET_NAME[] = "UNIX_domain";
 static int _vold_monitor_socket_fd           = -1;
 
-
 static void vold_monitor_open_socket(void)
 {
     TRACE;
@@ -82,6 +81,8 @@ static void vold_monitor_open_socket(void)
     }
 }
 
+/* Track state of external SD */
+bool extsd_present = false;
 
 /*
     bionic does not have pthread_cancel.
@@ -161,10 +162,12 @@ static void* vold_monitor_run(void* nothing)
             else if(strcmp(msg, "Volume sdcard /mnt/external_sd state changed from 4 (Mounted) to 5 (Unmounting)") == 0)
             {
                 /* We are loosing the external sdcard, inform Rockbox. */
+                extsd_present = false;
             }
             else  if(strcmp(msg, "Volume sdcard /mnt/external_sd state changed from 3 (Checking) to 4 (Mounted)") == 0)
             {
                 /* The external sdcard is back, inform Rockbox. */
+                extsd_present = true;
             }
         }
     }

firmware/target/hosted/ibasso/vold-ibasso.h

@@ -38,5 +38,7 @@ void vold_monitor_start(void);
 */
 bool vold_monitor_forced_close_imminent(void);
 
+/* Track the state of the SD card */
+extern bool extsd_present;
 
 #endif