sd-as3525v2: add card hotswap to sd_thread

Clip+: add (disabled) configuration for µSD slot

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@25194 a1c6a512-1295-4272-9138-f99709370657

firmware/export/config/sansaclipplus.h

@@ -9,6 +9,14 @@
 #define FIRMWARE_OFFSET_FILE_DATA 8
 #define FIRMWARE_OFFSET_FILE_CRC 0
 
+#if 0   /* TODO */
+#ifndef BOOTLOADER
+#define HAVE_MULTIDRIVE
+#define NUM_DRIVES 2
+#define HAVE_HOTSWAP
+#endif
+#endif
+
 #if 0 /* disabled since there is no driver (yet) */
 
 #define HW_SAMPR_CAPS       (SAMPR_CAP_44)

firmware/target/arm/as3525/sd-as3525v2.c

@@ -39,6 +39,10 @@
 #include "ata_idle_notify.h"
 #include "sd.h"
 
+#ifdef HAVE_HOTSWAP
+#include "disk.h"
+#endif
+
 #include "lcd.h"
 #include <stdarg.h>
 #include "sysfont.h"
@@ -484,6 +488,50 @@ static void sd_thread(void)
 
         switch ( ev.id )
         {
+#ifdef HAVE_HOTSWAP
+        case SYS_HOTSWAP_INSERTED:
+        case SYS_HOTSWAP_EXTRACTED:
+        {
+            int microsd_init = 1;
+            fat_lock();          /* lock-out FAT activity first -
+                                    prevent deadlocking via disk_mount that
+                                    would cause a reverse-order attempt with
+                                    another thread */
+            mutex_lock(&sd_mtx); /* lock-out card activity - direct calls
+                                    into driver that bypass the fat cache */
+
+            /* We now have exclusive control of fat cache and ata */
+
+            disk_unmount(SD_SLOT_AS3525);     /* release "by force", ensure file
+                                    descriptors aren't leaked and any busy
+                                    ones are invalid if mounting */
+            /* Force card init for new card, re-init for re-inserted one or
+             * clear if the last attempt to init failed with an error. */
+            card_info[SD_SLOT_AS3525].initialized = 0;
+
+            if (ev.id == SYS_HOTSWAP_INSERTED)
+            {
+                sd_enable(true);
+                microsd_init = sd_init_card(SD_SLOT_AS3525);
+                if (microsd_init < 0) /* initialisation failed */
+                    panicf("microSD init failed : %d", microsd_init);
+
+                microsd_init = disk_mount(SD_SLOT_AS3525); /* 0 if fail */
+            }
+
+            /*
+             * Mount succeeded, or this was an EXTRACTED event,
+             * in both cases notify the system about the changed filesystems
+             */
+            if (microsd_init)
+                queue_broadcast(SYS_FS_CHANGED, 0);
+            /* Access is now safe */
+            mutex_unlock(&sd_mtx);
+            fat_unlock();
+            sd_enable(false);
+        }
+            break;
+#endif
         case SYS_TIMEOUT:
             if (TIME_BEFORE(current_tick, last_disk_activity+(3*HZ)))
             {