Do some crackdown on kernel object reinitialization after they could be in use and use before initialization. For c200/e200: Be sure fat cache and ata locks are acquired in the proper order during hot swapping. Delay hotswap monitoring until after initial file mounting (address 2nd kobj concern + possible call of fat driver before init).

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@16636 a1c6a512-1295-4272-9138-f99709370657

firmware/common/disk.c

@@ -104,7 +104,7 @@ int disk_mount_all(void)
     int mounted;
     int i;
     
-#ifdef HAVE_MMC
+#if defined(HAVE_MMC) || defined(HAVE_HOTSWAP)
     card_enable_monitoring(false);
 #endif
 
@@ -118,9 +118,8 @@ int disk_mount_all(void)
     {
         mounted += disk_mount(1); /* try 2nd "drive", too */
     }
-#ifdef HAVE_MMC
+
     card_enable_monitoring(true);
-#endif
 #endif
 
     return mounted;

firmware/drivers/audio/as3514.c

@@ -132,9 +132,6 @@ void audiohw_init(void)
 {
     unsigned int i;
 
-    /* reset I2C */
-    i2c_init();
-
     /* normal outputs for CDI and I2S pin groups */
     DEV_INIT2 &= ~0x300;
 

firmware/drivers/fat.c

@@ -172,6 +172,7 @@ struct bpb
 };
 
 static struct bpb fat_bpbs[NUM_VOLUMES]; /* mounted partition info */
+static bool initialized = false;
 
 static int update_fsinfo(IF_MV_NONVOID(struct bpb* fat_bpb));
 static int flush_fat(IF_MV_NONVOID(struct bpb* fat_bpb));
@@ -202,6 +203,18 @@ static char fat_cache_sectors[FAT_CACHE_SIZE][SECTOR_SIZE];
 static struct fat_cache_entry fat_cache[FAT_CACHE_SIZE];
 static struct mutex cache_mutex NOCACHEBSS_ATTR;
 
+#ifdef HAVE_HOTSWAP
+void fat_lock(void)
+{
+    mutex_lock(&cache_mutex);
+}
+
+void fat_unlock(void)
+{
+    mutex_unlock(&cache_mutex);
+}
+#endif
+
 static long cluster2sec(IF_MV2(struct bpb* fat_bpb,) long cluster)
 {
 #ifndef HAVE_MULTIVOLUME
@@ -240,7 +253,11 @@ void fat_init(void)
 {
     unsigned int i;
 
+    if (!initialized)
+    {
+        initialized = true;
         mutex_init(&cache_mutex);
+    }
 
     /* mark the FAT cache as unused */
     for(i = 0;i < FAT_CACHE_SIZE;i++)

firmware/export/fat.h

@@ -82,6 +82,10 @@ struct fat_dir
     unsigned char sectorcache[3][SECTOR_SIZE];
 };
 
+#ifdef HAVE_HOTSWAP
+extern void fat_lock(void);
+extern void fat_unlock(void);
+#endif
 
 extern void fat_init(void);
 extern int fat_mount(IF_MV2(int volume,) IF_MV2(int drive,) long startsector);

firmware/target/arm/i2c-pp.c

@@ -187,6 +187,7 @@ int pp_i2c_send(unsigned int addr, int data0, int data1)
 void i2c_init(void)
 {
     /* From ipodlinux */
+    mutex_init(&i2c_mtx);
 
 #ifdef IPOD_MINI
     /* GPIO port C disable port 0x10 */
@@ -231,7 +232,5 @@ void i2c_init(void)
 #endif
 #endif
 
-    mutex_init(&i2c_mtx);
-
     i2c_readbyte(0x8, 0);
 }

firmware/target/arm/sandisk/ata-c200_e200.c

@@ -16,7 +16,7 @@
  * KIND, either express or implied.
  *
  ****************************************************************************/
-#include "ata.h"
+#include "fat.h"
 #include "hotswap-target.h"
 #include "ata-target.h"
 #include "ata_idle_notify.h"
@@ -29,8 +29,8 @@
 #include "panic.h"
 #include "usb.h"
 
-#define BLOCK_SIZE      (512)
+#define BLOCK_SIZE      512
-#define SECTOR_SIZE     (512)
+#define SECTOR_SIZE     512
 #define BLOCKS_PER_BANK 0x7a7800
 
 #define STATUS_REG      (*(volatile unsigned int *)(0x70008204))
@@ -1045,22 +1045,33 @@ static void sd_thread(void)
         {
 #ifdef HAVE_HOTSWAP
         case SYS_HOTSWAP_INSERTED:
-            mutex_lock(&sd_mtx); /* Lock-out card activity */
-            card_info[1].initialized = 0;   
-            sd_status[1].retry = 0; 
-            disk_unmount(1); /* Force remount */
-            disk_mount(1); /* mount microSD card */
-            queue_broadcast(SYS_FS_CHANGED, 0);
-            mutex_unlock(&sd_mtx);
-            break;
-       
         case SYS_HOTSWAP_EXTRACTED:
-            mutex_lock(&sd_mtx); /* Lock-out card activity */
+            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(1);     /* 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[1].initialized = 0;
             sd_status[1].retry = 0; 
-            disk_unmount(1); /* release "by force" */
+
+            if (ev.id == SYS_HOTSWAP_INSERTED)
+                disk_mount(1);
+
             queue_broadcast(SYS_FS_CHANGED, 0);
+
+            /* Access is now safe */
             mutex_unlock(&sd_mtx);
+            fat_unlock();
             break;
 #endif
         case SYS_TIMEOUT:
@@ -1135,6 +1146,28 @@ void ata_enable(bool on)
     }
 }
 
+#ifdef HAVE_HOTSWAP
+void card_enable_monitoring(bool on)
+{
+    if (on)
+    {
+#ifdef SANSA_E200
+        GPIO_SET_BITWISE(GPIOA_INT_EN, 0x80);
+#elif defined(SANSA_C200)
+        GPIO_SET_BITWISE(GPIOL_INT_EN, 0x08);
+#endif
+    }
+    else
+    {
+#ifdef SANSA_E200
+        GPIO_CLEAR_BITWISE(GPIOA_INT_EN, 0x80);
+#elif defined(SANSA_C200)
+        GPIO_CLEAR_BITWISE(GPIOL_INT_EN, 0x08);
+#endif
+    }
+}
+#endif
+
 int ata_init(void)
 {
     int ret = 0;
@@ -1193,7 +1226,6 @@ int ata_init(void)
         GPIOA_INT_LEV = (0x80 << 8) | (~GPIOA_INPUT_VAL & 0x80);
 
         GPIOA_INT_CLR = 0x80;
-        GPIO_SET_BITWISE(GPIOA_INT_EN, 0x80);
 #elif defined SANSA_C200
         CPU_INT_EN = HI_MASK;
         CPU_HI_INT_EN = GPIO2_MASK;
@@ -1201,7 +1233,6 @@ int ata_init(void)
         GPIOL_INT_LEV = (0x08 << 8) | (~GPIOL_INPUT_VAL & 0x08);
 
         GPIOL_INT_CLR = 0x08;
-        GPIO_SET_BITWISE(GPIOL_INT_EN, 0x08);
 #endif
 #endif
     }

firmware/target/arm/wmcodec-pp.c

@@ -41,9 +41,6 @@
  * Initialise the PP I2C and I2S.
  */
 void audiohw_init(void) {
-    /* reset I2C */
-    i2c_init();
-
 #ifdef CPU_PP502x
     /* normal outputs for CDI and I2S pin groups */
     DEV_INIT2 &= ~0x300;